DOCUMENT RESUME
CE 001 073

ED 089 027
AUTHORTITLE
INSTITUTION

Masson, Don, Ed.
The Story of the Plastics Industry.
Society of the Plastics Industry, Inc., New York,N.Y.

PUB DATE
NOTE

Oct 72EDRS PRICEDESCRIPTORS

MF-$0.75 HC-$1.85 PLUS POSTAGE
Chemical Industry; *Development; *Industry;
Manufacturing; *Merchandise Ihformation; Organic
Chemistry; *Plastics; Production Techniques*Plastics Industry

IDENTIFIERS

44p.

ABSTRACTThis is an illustrated informative booklet, designed
to serve members of the Society of the Plastics Industry, Inc., andthe plastics industry as a whole. It provides basic information about
the industry's history and growth, plastics raw materials, typicaluses of plastics, properties, and methods of prccessing andfabricating. (Author/DS)

The story of the LJ

industry
7L.V,

r

U.S. DEPARTMENT OF HEALTH;LDLICATION & WELFARE
NATIONAL INSTITUTE OFEDUCATION

DOT''''AENT HAS BEEN REPRO
EyAcTLy AS RECEIVED FROM

1.-ir -17 RSON OR ORGANIZAT ;ON ORIGIN

IT POINTS OF 'ITV.; OR 0; INIONSSTATE? DO NOT NECESS:.R!LY REEVE.ENT OFFICIAL NAT ,ONAL INSTITLOF
DUCAT ION POSITION OR ROUENFOREWORD

This is an informative booklet, designed to serve
members of The Society of the Plastics Industry, Inc.,and the plastics industry at: a whole. It provides
basic information about the industry's history,
growth, plastics raw materials typical end useswith illustrations, properties, methods of processing
and fabricating. It should not be considered as anencyclopedia or technical directory.
Additional copies of this booklet may be obtained atcost from the Public Relations Committee of SPI for
distribution to employee groups, civic organizations
avid educational institutions.

Permission to quote or reproduce parts of thisbooklet is granted, provided full credit isgiven to
The Society of the Plastics Industry, Inc.

TWELFTH REVISED EDITION

Prepared under the direction of
The Public Relations Committee

THE SOCIETY. OF THE
PLASTICS INDUSTRY, INC.
250 Park Avenue, New York, N, Y. 10017
Edited by Don Masson

Printed by The John B. Watkins Company

October, 1972

In 1868, a young printer mixed pyroxylin, made from cotton and nitricacid, with solid camphor. John Wesley
Hyatt came up with Celluloid, the first

American plastic. Even more important, he started what is now one of the

few billion dollar industries in thethe plastics industry.
Now in its greatest growth period,

United States

The story of the

COTindustry

the U. S. plastics industry in 1969 produced over 16 billion pounds of resins.
With a more than 200 per cent increasein production in the last ten years, theindustry has grown both in volume
and in variety of materials, each withspecial properties.
More and more businessmen havesought information on how plastics
can improve their products, cut theircosts, streamline their production.

Students, technicians, workers havesought facts on employment opportunities, plastics courses offered bycolleges and trade schools, and supplementary information sources.
The growth of the plastics industry
has been so rapid, however, that publicawareness of the sources of information on the major plastics, their characteristics and proper use has not kept

abreast of the interest of either thebusinessman or the student.

This booklet :s prepared by The
Society of the Plastics Industry, Inc.,
representing 1,350 companies engaged
in some phase of the plastics industry,
to answer basic questions about theindustry, its materials and production
methods.

1=IMIMPIIIMINEMENIM

How theplastics industry took its second major step
forward, In 1909, Dr. Leo Hendrik Baekeland introduced phenol-formaldehyde resins.
While others in the field of chemistry 1-ad

Industryand formaldehyde, Dr. Baekeland was theGrew

the two.. The first phenolic in this country
was given the trademark, Bakelite, coinedfrom his name.

experimented with the combination of phenol
first to obtain a controllable reaction between

Dr. Baekeland was also the first to develop
techniques for converting this plastic to commercial use. His patents covered the produc-

A century ago there was no such thing as acommercial plastic in the United States. We
had not learned that by combining such basicorganic materials as oxygen, hydrogen, nitrogen, chlorine and sulfur, new man-made materials could be created materials which,through variations in the amount and combination of basis organic and inorganic ingredients, could be made with almost any
quality desired in an end product.
In creating the first commercial plastic in
the United States in 1868, John Wesley
Hyatt did so in response to a competition

tion of a phenolic that could be cast (likemarbleized clock bases), a compound that
could be formed under heat and pressure(like an electric iron handle), and solutions
that could be used in making laminates (likerestaurant table tops),
From 1909 to 1926 two more plastic materials were developed cold molded andcasein. Then, the tempo of plastics development increased consistently as is evident in
the accompanying list which gives the year
each plastic was introduced and identifies itwith a familiar product for each type ofplastic.

sponsored by a manufacturer of billiard balls.
It came about when a shortage developed in

Cellulose acetate was the next large-volume plastic to be developed commercially inivcry from which billiard balls were made.
Hyatt, a determined full-time printer andthis country. Launched in 1927, it wasavailable only in sheets, rods and tubes until
1929 when it appeared as a molding material and became the first injection-molded

part-time inventor, developed Celluloid. Con-

currently, in England, development was inprogress on the use of pyroxylin in lacquers
and in other coating materials.
Celluloid, the first American plastic, wassoon found to have many uses. Coloredpink, it was quickly adopted by dentists as

a replacement for hard rubber in denture
plates. It will be remembered as the material from which wipe-clean collars, cuffs

and shirt fronts were made, and as thewindow curtains on the early automobiles.
The first photographic film used by Eastman

was made of Celluloid in the '80's to produce the first motion picaire film in 1882.
Forty-one years were to pass before the

2 THE STORY OF THE PLASTICS INDUSTRY

plastic.
The

first of the vinyl resins, polyvinyl

chloride, came on the market in this country

in 1927. The vinyls now constitute quitea family of resins, the most important of
besides polyvinyl chloridearepolyvinyl acetate, polyvinyl chloride-acetate,
polyvinyl acetal, polyvinylidene chloride.
While polystyrene became commerciallywhichavailable in this country in 1938, it is oneof the oldest synthetic resins. It dates backto 1831 when it was first isolated. Today,polystyrene is one of the volume plastics,
most familiar in toys and housewares.

Polyethylene was introduced in 1942. It
was originally produced in England and firstmade in the United States for the U. S. Navyas an important electrical insulation. Polyethylene became the first plastic to reach abillion pound annual production rate.

INTRODUCTION OF PLASTICS MATERIALS
DATE

tiimpLE.

:IMAtERIALF

1868

CELLULOSE NITRATEEYE GLASS FRAMES

1909

PHENOL-FORMALDEHYDETELEPHONE HANDSET1909

COLD MOLDED)(Noes AND HANDLES1919

CASEINKNITTING NEEDLES

1926

ALKYD

ELECTRICAL BASES

1926

ANALINL-FORMALDEHYDETERMINAL BOARDS1927

CELLULOSE ACETATE

TOOTH BRUSHES, PACKAGING

1927

POLYVINYL CHLORIDE

RAIN COATS

1929

UREA-FORMALDEHYDE

L IGHTING FIXTURES1935

ETHYL CELLULOSEFLASHLIGHT CASES1936

ACRYLIC

BRUSH BACKS, DISPLAYS1936

POLYVINYL ACETATEFLASH BULB LINING

1939

CELLULOSE ACETATE BUTYRATEIRRIGATION PIPE

1938

POLYSTYRENE OR STYRENEKITCHEN HOUSEWARES1938

NYLON (POLYAMIDE)

GEARS

1938

POLYVINYL ACETALSAFETY GLASS INTERLAYER

1939

POLYVINYLIDENE CHLORIDE

AUTO SEAT COVERS1939

MELAMINE-FORMALDEHYDETABLEWARE

1942

POLYESTERBOAT HULLS

1942

POLYETHYLENESQUEEZABLE BOTTLES

1943

FLUOROCARBON_

INDUSTRIAL GASKETS1943

SILICONEMOTOR INSULATION1945

CELLULOSE PROPIONATEAUTOMATIC PENS AND PENCILS

1947

EPDXY

TOOLS AND JIGS1948

ACRYLONITRILE-BUTADIENE-STYRENE

LUGGAGE

1949

ALLYLICELECTRICAL CONNECTORS1954

POLYURETHANE OR URETHANE

FOAM CUSHIONS1956

ACETAL

AUTOMOTIVE PARTS

1957

POLYPROPYLENE

1937

POLYCARBONATE

1959

CHLORINATED POLYETHER

1962

PHENOXY.

--SAFETY HELMETSAPPLIANCE PARTSVALVES AND FITTINGSBOTTLES-_..---- -----_----- -_____- ________----_-_---------1962

POLYALLOMER

1964

IONOMER

1964

POLYPHENYLENE OXIDEBATTERY CASES1964

FOLTIMIDE

BEARINGS1964

ETHYLENE-VINYL ACETATEHEAVY GAUGE FLEXIBLE SHEETING

1965

PARYLENE

INSA-ATING COATINGS

1965

POLYSULFONEELECTRICAL/ELECTRONIC PARTSTYPEWRITER CASESSKIN PACKAGES_

3

resin materials in 1967 was about 14.47 billion pounds. This fact, alone, is indicative of
the importance of the plastics industry in our

The plastics industry runs into billions ofboth dollar volume of finished products andin the pounds of raw material produced,
Three plastic materials have reached or exceed 2 billion pounds :annual production:
Polyethylene 3.8 billion; Vinyl 2.8 billion: and Styrene. 2.5 billion. The Societyof the Plastics Industry, Inc., estimates thatthe production of all synthetic plastics andv, odd today..

Plastics companies numbering over 5,700

are located throughout tin United States.
Approximately 50 per cent are in the East,
34 per cent in the Midwest, 13 per cent on
the West Coast, and 3 per cent. elsewhere.

SYNTHETIC PLASTICS AND RESIN Di ATERIALS PRODUCTION

U. S. TANIFP COMMISSION
14,470,000,
tstiotatsl by The Society of tile Plastics lslostry,lc

6,143,000,000 LBS.

3,738,916,000 LBS.

2,150,518,000 LBS.

818,020.000 LBS.

276,814,363 LBS.

95,133,384 IBS.

30,867,752 LBS.

5,944,133 LBS.

1922

1e30

1935

4 THE STORY OF THE PLASTICS INDUSTRY

1940

1945

1950

1955

1960

1987

them we might soon be back in the "darkages."
The continuing development of new plas-

Plastics

tic materials broadens the industry's field of
applications. Even more, it is indicative ofPartnerplastics' ability to produce equally good

products at a lower cost, better products atthe same cost, or products that could not be
manufactured without them.
World War II gave great impetus to theindustry. In meeting exacting defense service
requirements, plastics demonstrated theirversatility and wide range of important prop-of Today's
Livingerties, They proved their high tensile andimpact strength, lightness, resistance to corrosion, low moisture absorption, resistance tosalt water and many chemicals, transparency,

Plastics pixy a vital role in peace, defense,
and in war. They were instrumental in thedevelopment of the automobile, airplane,
missile and communications. They provided
the material needed to develop the automobile ignition system. They made possible
the pioneering flights of Alcock and Brown,
Lindbergh, Byrd, Shepard, and Glenn. It
is said that the Wright Brothers in the '80's
used plastics cellulose nitrate solutions on
glider wings and on the wings of the plane

adaptebility to varied climatic conditions,and flexibility even at low temperatures.
Designers, engineers, and architects constantly analyze material and performance requirements of varied products to determine
the suitability of plastics for new end uses;and plastics materials are being formulatedwith scientific precision and skill to meetin which they made their historic flight inthese new market applications.
The plastics industry is continuing to expand its facilities of research, development
and production .. . to meet both civilian and1903.
The lifelines of all communications

defense requirements. The Society of the
Plastics Industry, Inc., estimates that sincetele-phone, radio, television, radar, sonar, telestar are based on plastics as insulation andother vital components. The comfort of ourhomes is increased in countless ways . .
through foamed cushions for furniture, easyto-clean upholstery, protective coatings forthe home and industrial equipment, soft illumination for translucent lighting, floor coverings that are resistant to spilled liquids andfoods. All of these and many more can be
attributed to resins and plastics. Without

5

1946 the plastics industry has at least tripledinvestments in raw materials plastics

its

plants. Hundreds of millions of dollars arebeing spent in plastics research for the development of new resins and the improvement of existing plastics to meet the multifold requirements of modern industry.
Today, plastics are accepted as basic materials used by designers and engineers. They
take their place in industry along with metal,
glass, wood and paper.

=11=MINIEM=m11

Plastics are man-made materials, in contrast

to nature's materials like wood and metal.
A generally accepted definition is: Any one

Plastics:
What They.
Are

1.1.1111i1

of a large and varied group of materials consisting wholly or in part of combinations ofcarbon with oxygen, hydrogen, nitrogen andother organic and inorganic elements which,while solid in the finished state, at somestage in its manufacture is made liquid, andthus capable of being formed into various

shapes, most usually through the application, either singly or together, of heat andpressure.

THERMOPLASTIC:

Mese plisticsieCome Soft when exposed;
to sufficient heat and herded when cooled,no matter hovi often' thi process isgroup fall ABS;'....
:(iCrylenitrile-bittadieneltyrene);acrylic; MP cellulosiCiwethylene-vinyl.
acetate; fluorocarbon, lOnOmer, nylon,

parYline;phaniuty;irlyalliner, polycar-,_bona* polyethylene, PoliphenylOxide;:`:pliiimideiPolypropyiene; polystyrene;
lystilfOne; urethane; and vinyl.

THERMOSET:PO ::the plastics materials belonging,tp_ thisgrew Piiiajet into permanent Sharkyihepressure "are aka.tiiitherif:
fOrrning.'. Hiheatink willnot Softens

niaterialS;ilhirmOietting pliStICSV
inciutle: alkyd, amino'Ind -Unita
in; cold molded, ePoitY;PhenOlIC.;

polYirster,7anWsilieone.'

0 THE STORY OF THE PLASTICS INDUSTRY

Plastics are a family of materials not asingle material each member of which has
its special advantages.

Being man-trade, plastics raw materials
are capable of being variously combined togive most any property desired in an end
product. But these are controlled variations
unlike those of nature's products.
The widespread and growing use of plastics in almost every phase of modern living
can be credited in large part to their unique
combinations of advantages. These advantages are light weight, range of color,, good

The Industry
That Produces

Plastics

physical properties, adaptability to massproduction methods and, often, lower cost.
Some plastics can be sterilized.

Aside from the range of uses attributable
to the special qualities of different plastics,
these materials achieve still greater variety
through the many forms in which they canbe produced.
They may be made into definite shapes likedinnerware and electric switchboxes.
They may be made into flexible film andsheeting familiar as shower curtains andToday, a minimum of 5,700 companies in
the United States make plastics their business. They divide into three large categories
which sometimes overlap the plastics materials manufacturer who produces the basic

plastic resin or rompourfd, the processor
who converts plastic into solid shape, thefabricator and finisher who further fashions
and decorates the plastic.

upholstery.

PLASTICS MATERIALS MANUFACTURERS

They may be made into sheets, rods andtubes that are later shaped or machined into
internally-lighted signs, airplane blisters.
They may be made into filaments for use
in household screening, industrial strainers

The primary function of the materials
companies is the formulation of a plastic
from basic chemicals. This plastic com-and sieves.

They may be made into netting in a variety of patterns and sizes.
They may be used as a coating on textiles
and paper.
They may be used to bind together suchmaterials as fibers of glass and sheets ofpaper or wood to form boat hulls, airplane
wing tips, table tops.

They may be used as adhesives, and inlacquers and paints uses which are but
mentioned in this booklet which deals specifically with solid forms of plastics.

Whatever their properties or form, plastics

all fall into one of two groups

thermoplastic or the thermosetting.

7

thepound is sold in the form of granules, powder, pellets, flake, and liquid resins or solutions for processing into finished products.
Some plastics materials companies may go astep further and form the resin into sheets,
rods, tubes, film.

The membership of The Society of the
Plastics Industry, Inc. lists 175 companies as

manufacturers of plastics materials in the
United States. A majority are chemical
manufacturing companies. Some purchasechemicals from which they formulate theplastic resins and compounds. Some only
make the compound, purchasing the resin.
THE PROCESSOR

Plastics processors divide into several different classifications:MATERIAL MANUFACTURERS

FABRICATORSMOLDERS

produce finished products byforming the plastic in a mold of the desired
shape. They number about 1,700.
MOLDERS

vacuum deposition to coat fabric, metal andpaper with plastics. They number over 70.
THE FABRICATOR AND FINISHER

divide into two groups. The
first group turns out sheets, film, sheeting,
EXTRUDERSof the thread-like plastic filaments which,

Plastics sheets, rods, tubes and special
shapes are the principal forms with which
fabricators and, finishers work. Using all
types of machine tools, they complete theconversion of these plastics forms into suchwhen woven into cloth, find use as seat cov-

finished products as industrial parts, jewelry,

ers for autos, buses, trains and furniture,
and as insect and industrial screening. Ex-

signs.

rods, tubing, special. shapes, pipe, wire covering. The second group includes producers

truders number in all about 300.
FILM AND SHEETING PROCESSORS

makevinyl sheeting and film either by calendering,

casting, or extruding. There are about 60
companies in the field.
HIGF.-PRESSURE LAMINATORS

form sheets,rods and tubes from paper, cloth and wood
impregnated with resin solutions. These com-panies are about 50.
REINFORCED PLASTICS MANUFACTURERS

LiqUid resinspolyesters, epoxies, phenolics,
and silicones are combined with such reinforcements as glass fibers, asbestos, synthetic fibers and sisal to form strong, rigid

structural plastics and plastic products bymolding or forming. There are about 400
companies.

make use of calendering, spreadcoating, preimpregnating, and dipping and
COATERS

8 THE STORY OF THE PLASTICS INDUSTRY

Vacuum forming is an important methodof fabricating sheet mate' ials. Working withrigid sheet material, fabricators also form
such things as airplane canopies, televisionlenses.

One of the newest and largest branches ofthe plastics industry comprises companies
that produce from plastic sheeting and film
such articles as shower curtains, rainwear,
inflatables, upholstery, luggage, closet accessories.

Between the producer of the film andsheeting and the fabricator of a finishedproduct there may be a printer who prints
a design on the material, and an embosser
who forms a textured pattern on its surface.
Other finishers metal-plate rigid plastic
parts or otherwise give them decorative orpractical surface markings.
There are approximately 1500 fabricators
working on rigid plastics and another 1500

engaged in making film and sheeting into
finished products.

Dimensional stability Parts are dimensionallystable under a wide variety of conditions.

The Plastics

FORMS AND METHODS OF FORMING

Materials

ABS plastics are available as powder or granules
for injection molding, extrusion and calenderingand as sheet for vacuum forming.

They WorkWithACETAL RESIN

Acetal resin is a rigid thermoplastic developedin 1956.
ABS PLASTICSACRYLONITRILE-BUTADIENE-STYRENE

ABS plastics are thermoplastic materials developed in 1948. There is also a SAN (styreneacrylonitrile) version of this family of plastics.

TYPICAL USES
Pipe, pipe fittings, wheels. football helmets,
safety helmets, textile bobbins, TV antenna
brackets, valve bodies, refrigerator parts, battery cases, automotive parts, cable flodts, tote
boxes, water pump impellers, terminal blocks,
strike brackets, business machine trays, children's skates, utensil handles, tool handles,
radio cases are typical products.

PROPERTIES
ABS plastics possess outStrong and toughstanding impact strength in combination withTYPICAL USES
This resin was developed for use in fields once
dominated by die-cast metals. Uses include
automobile instrument clusters, carburetor
parts, gears, bearings and bushings, door handles, plumbing fixtures, and moving parts inhome appliances and business machines.

PROPERTIES
Rigidity

Acetal resin is extremely rigid with-out being brittle. It retains these properties
under adverse conditions of temperature andhumidity.

Chemical resistanceResistant to most sol-

vents.

Odorless, tasteless, non-toxic.
Strength
Extreme toughness, outstanding
tensile strength, stiffness, and fatigue life.

high mechanical (tensile, flexural, etc.) strength.

FORMS AND METHODS OF FORMING
Acetal resin is produced in powder form forSome formulations offer excellent toughness

molding and extrusion.

down to 60°F.
Heat resistance

These compounds can be used

at temperatures of 175°F. to 212°F. Newer
formulations withstand temperatures greaterthan 212°F.
Chemical resistance

ABS plastics are resistantto acids, alkalis, salts and, in many cases, toaliphatic hydrocarbons.
Electrical qualities
ABS plastics have goodoverall electrical properties.

9

ACRYLIC

Acrylic, or polymethylmethacrylate, plastic isa thermoplastic material, commercially intro-

duced in the U.S.A. in 1936. A copolymer,
methyl methacrylate-styrene is also available.

TYPICAL USESFORMS AND METHODS OF FORMING

Airplane canopies and windows, camera lenses,
facing paneis, dome structure enclosure glazingin building construction, outdoor signs, lighting
diffusers, automobile tail lights, nameplates forhome appliances. TV shields, and skylights.

Acrylics are available as rigid sheets, rods andtubes, and molding powders.
Plastic products can be produced by fabricating of sheets. rods and tubes, hot forming ofsheets, injection and compression molding of
powder, extrusion, casting.

PROPERTIES
Optical clarity

Acrylics offer exceptional clarity and good light transmission. In crystal-clear
form, acrylic can pipe light pick it up at oneedge and transmit it unseen, even around curves.

ALKYD

Acrylics are strong. rigid and resistant to sharp blows. Contact with cleaning
Strengthcloths containing grit, kitchen scouring powders

and such abrading materials as steel wool
should be avoided.
Weather and temperature resistance

Weather-ing does not affect the transparency, physicalstability and electrical properties of acrylic.
Long outdoor exposure of colorless acrylic has
no significant effect on its use as a transparent
material. Acrylic does not become brittle at
low temperatures, Some cast acrylic compositions withstand bOing water, and heat-resistantmolding composions are undistorted up to
200°F. Acrylics will not withstand steam
sterilizing and, if subjected to boiling water,
will start to lose shape. This acrylic plastic ma-

terial has a slow burning rate and does not

Alkyd plastic is a thermosetting material, developed in 1926, which has its widest application in enamels, paints, lacquers and similar
applications. It was introduced as a molding
material in 1948. Production in 1967 is estimated at around 680,000,000 lbs.

TYPICAL USES
Representative applications of alkyd molding
materials are parts of automobile starters, fuses,
light switches,

electric motor insulator andmounting cases, television tuning devices andtube supports. Enamels and lacquers for automobiles, refrigerators, stoves, farm machinery
are typical uses for the liquid form of alkyd
plastic.

flash ignite.

PROPERTIESElectrical properties
insulator.

Electrical properties

Acrylic is an excellent

Acrylics are inherently
colorless but are also produced in a full rangeof transparent, translucent and opaque colors.
They are also made with corrugated and patColor and texture

terned surfaces.

This plastic is warm andpleasant to the touch.

Alkyd molding materials
have excellent dielectric strength and will resist

more than 350 volts per mil. They have highresistance to electrical leakage. Molded alkyd
materials also afford excellent arc resistance.
Weather and temperature resistanceand are dimensionally stable under high temperatures. They also have good resistance toOdorless, tasteless, non-toxic.

moisture.

Acrylics are unaffectedby most household chemicals such as weak andstrong alkalis, bleaching compounds and window cleaning solutions, by salt, vinegar, animaland mineral oils, waxes, and foods commonly

Chemical resistanceChemical resistanceencountered in the home. This plastic is attacked ,by perfume, gasoline, cleaning fluids,
acetone, chloroform, and strong solutions ofoxidizing acids.

1 0 THE STORY OF THE PLASTICS INDUSTRY

Alkyd

molding powders have excellent heat resistance

Molded alkyd is resistantto acids, ketones, esters, alcohol, chlorinatedcompounds, essential oils.

FORMS AND METHODS OF FORMING
Alkyds are available as molding powder andliquid resin.

Finished molded products are produced bycompression molding.

-. ......

staF

.....

1

1. Automative parts molded ofacrylonitrile - butadiene - styrene
plastic. Metallized dash panels
and instrument cluster take tookof metal, but incorporate greater
durability and impact resistance.

2. Colorful telephone desk sets
are molded of ABS plastic which

provides outstanding impact
strength and is unaffected byperspiration.
3. Acetal molded switch back(foreground) for electric wind-shield wiper control is fitted tometal housing above. The acetal
molded slide (right) moves insideswitch back and makes metal tometal contact with lugs to acfor speed

tivate wipers andcontrol.

4. Weather and break resistance,light weight and clarity are reasons for using acrylic sheet forthe dome enclosure.

5. Molded alkyd distributor cap
used on racing car engine. Alkyd

was used because of its highelectrical surface resistivity andretention of superior electricalproperties at under-the-hood racing temperature.

6. Base of this circuit breaker,
used in aircraft power generator
systems, is molded of allylic. Useof glass-filled diallyl phthalate
resip-base compound virtuallyeliminated rejects.

7'use molding powders with a variety of fillers
or prepreg of coated glass fiber, other textiles,

ALLYLIC

paper, etc.
Finished articles

Ally lics are thermosetting materials developedsince World War II. The most widely used of
its prepolymers, diallyl phthalate resin, was introluced commercially in 1949.

be made by transfer,compression, injection or extrusion molding;lamination; coating, both powder and liquid;
impregnation.

TYPICAL USES
Electronic parts, electrical connectors, bases,

A7,7:1NO PLASTICS

and housings, etc. Low and high pressure lami-

MELAMINE AND UREA

nates, both reinforced plastics and decorative
types.

PROPERTIESHigh dielectric strength, low electrical loss, low dielectric constant over a wide
Electricalfrequency range, excellent insulation resistanceand arc resistance. Unmatched ability to retain
its excellent electrical properties under condi-

tions of high humidity with rapid and full recovery of properties on drying.
Heat, Moisture, Staining, Chemical, andAlly lic plastics can be
Weather Resistanceproduced to withstand constant use at up to350° F. and colored products have excellent
color stability at high temperatures.
These plastics have practically no moisture absorption and are highly resistant to decomposition by practically all chemicals. Consequently,
allylic

plastics

arehighlystain

resistant.

Allylics have superior resistance to the adverse

effects of weathering, and even thin overlays
will greatly improve the weathering ability ofother materials such as polyester glass fiber

Amino plastics are thermosetting materials.
Melamine, developed in 1939, and urea, developed in 1929, together reached a productionlevel in 1967 of approximately 740,000,000 lbs.

TYPICAL USES
Melamine
Familiar in colorful tableware,melamine also finds wide use in distributor
heads, buttons and hearing aid cases. It is also
used in laminate surfaces, like table tops, as aplywood adhesive, for baking enamel finishes,
and as a textile and paper treatment.
Urea
Representative molded urea products
are closures, scale housings, lamp reflectors,

radio cabinets, electrical devices, buttons, appliance housings, stove knobs and handles. In
resin form it is used as baking enamel coatings,
plywood adhesives, and paper and textile treatment.

sheet.

PROPERTIES

Odorless, Tasteless, Insoluble.

Colorful

Unusual Dimensional Stability During andAfter Molding.
Color Ally lic plastics can be produced in a

Both melamine and urea offer a fullrange of translucent and opaque colors, colors
which have the advantage of being lightfast.
They give a glossy surface.

fullrange of opaque and transparent colors
which are stable under the most adverse con-Strength
Both melamine and urea are very
hard, scratch-resistant materials. They are

ditions.

strong but not unbreakable, and should be

FORMS AND METHODS OF FORMING
Allylics are available in the form of monomers
and prepolymers. Also available are ready -to1

2 THE STORY OF THE PLASTICS INDUSTRY

guarded against hard blows. There are special
high shock-resistant and tl'ipact-resistant types.
Chemical resistance Both melamine and urea
are unaffected by detergents, cleaning fluids(like carbon tetrachloride and gasoline), nailpolish and remover, alcohol, oils, grease.
Melamine andHeat and weather resistanceurea perform satisfactorily over a wide temperature range from as low as 70°F. for both
plastics to a continuous operating temperatureof 170°F. for urea and 210°F. for melamine.
They maintain their dimensions well and, formost indoor uses, may be considered completely permanent. Neither material should be usedin an oven or over a flame, as discoloration or
charring may occur. However, neither will burnor soften in contact with a flame.
Both melamine andurea have good electrical qualities.
Electrical characteristics

FORMS AND METHODS OF FORMING
The amino plastics (melamine and urea) areavailable as molding powders or granules, asa foamed material, in solution and as resins.
Finished products can be made by compression, transfer, plunger molding and laminatingwith wood, paper.

Casein products withstand dry cleaning and are not adversely afChemical resistancefected by contact with such liquids as gasoline,
nail polish, organic solvents and chemicals.
Weathering and water resistanceCasein isadversely affected by humidity and temperature changes. Immersion in liquids for long
periods at room temperature or short periods at
boiling temperature will cause casein to absorb
Water, swell, soften and break easily. It becomes more brittle as the temperature drops be -.
low freezing, and withstands only moderately
elevated temperatures without becoming pliable
or discoloring. It is not recommended for continuous outdoor exposure.

FORMS AND METHODS OF FORMING
Casein is available in rigid sheets, rods andtubes, as a powder and liquid.
Finished products are made by machining of
the sheets, rods and tubes.

CELLULOSICS

CASEIN

There are five types of cellulosics, all thermoCasein, the product of the protein of skim milk
reacted with formaldehyde, is a thermosetting
material developed in 1919.

TYPICAL USES
Buttons and buckles, beads, game counters,
knitting needles, atthesives, toys and novelty- counter items are all typical applications forcasein plastic.

PROPERTIES
Color and appearance

Casein takes a brilliant

surface polish and has a wide color range ofnear transparent and opaque colors. Many
extremely interesting and unusual variegatedpatterned color effects can be achieved withplastic. Cellulose nitrate was developed in 1868,

cellulose acetate in 1927, cellulose acetate butyrate in 1938, ethyl cellulose in 1935 andcellulose propionate in 1945. They reached avolume of approximately 195,000,000 lbs. in
1967.

TYPICAL USES
Cellulose acetate is used for rigid packaging
and is familiar as recording tape, photographic
film, as a lamination for book covers, in spectacle frames, toys, lamp shades, vacuum cleaner
parts, combs, shoe heels.
Cellulose acetate butyrate is used for packaging

and in steering wheels, portable radio cases,
pipe and tubing, tool handles.

this thermosetting material.

Cellulose propionate is used In packaging, ap-

Casein is a strong, rigid plastic. It
resists the effects of both blows and flexing.

pliance housings, telephone hand sets, pens.

Strength13

continued on page 15

1. Electrically heated compartmented baby food dish is moldedof melamine which resists attackfrom food, juices and detergents,
and is break resistant.

Facewide sun shade is madeof colorfully printed cellulose
acetate sheet. Shade is personal
wind-and-sun shield that lets2.

wearerlook atworld throughnew Op eyes. Flipped up, it becomes a bonnet; flipped down, aprotective veil to cut glare andwind.

3. Transparent cellulose acetate
butyrate pipe is used to Wow
cups several hundred feet fromthe manufacturing area to thepacking and shipping department.

Crystal-clear flowmeter colmade from extruded cellulose propionate plastic. Foursided column on rotatable basepermits direct and instant read4.

umn

ing of flow rate for any of four
inert industrial welding gases.

5. Cold molded plastics are used

for electrical appliance connectors and plugs, wiring devices,heat resisting ferrules, adapterswhere precision tolerances andheat resistance are prime factors.

6. Epoxy/glass filament woundexternally reinforced pressure
vessel, showing the combination

helical winding and circumferen
tial winding to attain design requirements.

7. Epoxy-based surface coatings
cure rapidly, withstand shockand exposure to chemicals, oil,grease and severe weathering.

3. One-use sanitary medical syr
inge eliminates costly sterilization. Syringe is blow-moldedfrom ethylene-vinyl acetate, immediately packaged, and remains

sterile and ready for use. Resin
combines toughness, flexibility
and clarity.

{'Ethyl cellulose is favored for edge moldings

on cabinets, electrical parts, flashlights.
Cellulose, nitrate is familiar in shoe heel covers,

and as a fabric coating.

PROPERTIES
Strong and durable

Cellulosics are among thetoughest of plastics. Normal rough usage will

not break cellulose parts. They retain a lustrous finish under normal conditions thoughabrasives will scar their surface.
Colorful The cellulosics may be transparent,
translucent or opaque in a wide variety of colors and in clear transparent.
Temperature and weather resistanceAll thecellulosics will withstand moderate heat. Except for cellulose acetate butyrate and cellulose
propionate which are suitable for outdoor use,
cellulosics should not be exposed to continuous
outdoor Weathering.
Electrical characteristics

All the cellulosics
have good electrical properties and are suitable
insulators against usual domestic and industrial
currents.

TYPES
Cellulose acetate (C/A)
This cellulosic is
resistant to most household chemicals, oil, gascrline and cleaning fluids but should be kept awayfrom alcohol, alkalies. This plastic is odorless,and tasteless. It is unaffected by normal mois-

ture and moderate heat and will withstandnormal usage at below freezing temperatures.
Water resistance and dimensional stability are
improved in high acetyl C/A.
Cellulose acetate butyrate (CAB) and Cellulose propionate (CP)Special weather-re-sistant formulations of these cellulosics alone
are suitable for outdoor use. Some types may
be used in water approaching boiling, and alltypes cara stand quite rough usage at sub-zerotemperatures. Their moisture absorption rate

is low. CAB and CP are resistant to mosthousehold chemicals, but are adversely affectedby alcohol, alkalies, paint removers, acetone.
Ethyl cellulose (E/C)
Of the cellulosics,
E/C best maintains its toughness and resiliency
continued on page 16

at sub-zero temperatures. It also offers good
dimensional stability over a wide range of temperatures and humidity conditions. It is unaffected by alkalies, weak acids, but should betiles, furnace covers, jigs and dies, in game

kept away from cleaning fluids, oils, solvents.

Cold molded plastics possess resistance to highheat, most alkalis and solvents, water and oils.
They also exhibit good arc resistance.

Cellulose nitrate (C/N)
This is made only
as sheet, film, rod and tube and in solution forcoating because it is flammable and cannot be
subjected to molding. C/N offers a wide rangeof colors and variegated color effects. It is resistant to most acids and alkalies.

FORMS AND METHODS OF FORMING
Cellulose acetate is available as pellets, sheets,
film, rods, tubes, strips, coated cord. It can bemade into finished products by injection, compression molding; extrusion; blow-molding andvacuum forming of sheets; laminating; machining; coating.

markers and toy building blocks.

PROPERTIESFORMS AND METHODS OF FORMING
Cold molded plastic materials are available ascompounds.

Finished articles are produced by molding
using heavy pressure in a rapid cycle, and by
subsequent curing.

The bitumin and phenolic types of cold
molded materials are cured either in ovens orat room temperature.
The cement-asbestos type of cold molded material is first cured in the presence of moistureand it is then baked.

Cellulose acetate butyrate is available in pellets,

sheets, rods, tubes, strips, and as a coating.
It can be made into finished products by injection, compression molding; extrusion blowing
and drawing of sheet; laminating; machining;

EPDXY

coating.

Cellulose propionate is available in pelicts forinjection, extrusion, or compression molding.
Ethyl cellulose is available as granules, flake,sheet, rod, tube, film and foil. It can be madeinto finished products by injection, compression
molding; extrusion; drawing; machining.
Cellulose nitrate is available as rods, tubes,
film, sheets for machining and eas a coating.

Epoxy resins are thermosetting and were firstmanufactured in the United States about 1947.
Production totalled approximately 145,000,000
lbs. in 1967.

TYPICAL USES
Protective coatings for appliances, plant structure' and equipment, automobiles, pipe, cansand drums, gymnasium floors and other hard-toprotect surfaces.
They firmly bond metals, ceramics, glass, plas-

COLD MOLDED

Cold molded plastics are thermosetting materials developed in 1909. There are three types:

tics, hard rubber and are used in combination
with glass fibers to manufacture reinforced
plastics products. Other products are: Printed
circuits, laminated tools and jigs, ducts andliquid storage tanks. Epoxies are employed mostcommonly in casting, potting, laminating, coating and adhesive-bonding applications.

bitumin, phenolic, and cement-asbestos.

PROPERTIESTYPICAL USES
Cold molded plastics find use in switch bases
and plugs, arc barriers and shoots, 3rd rail insulators, in small gears, handles and knobs,

Epoxies have good elecElectrical qualities
trical properties.
Water and weather resistance Epoxy base adhesives, due to their resistance to various chemi-

16 THE STORY OF THE PLASTICS INDUSTRY

cals and weathering, may be used where corrosion resistant joints are required.
Chemical resistance
Epoxies are resistant tomany chemicals. They have found widespreaduse for surface coating due to their excellent
adhesion, durability and chemical resistance.
Strength
Epoxies have good flexibility.

FORMS AND METHODS OF FORMING
Epoxies are available as molding compounds,
resins, foamed blocks, liquid solutions, adhesives, coatings, sealants.

FLUOROCARBONS

Fluorocarbons are thermoplastic materials introduced in 1943. They include tetrafluoroethylene(TFE), chlorotrifluoroethylene (CTFE), vinylidene fluoride (PVF2), and fluorinated ethylenepolypropylene (FEP).

TYPICAL USES
Fluorocarbon resins

are used inindustrial

applications such as: gaskets and packings,
seals, piston rings, and sealants (i.e. thread
sealant tape), linings for vessels, valves, pumps,
ETHYLENE-VINYLACETATE

pipe and fittings, hose, etc., bearing pads, slip
joints, pipe slides, expansion plates, anti-sticksurfaces (in form of films, sheeting and coat-ings), electrical wire insulation and compoEthylene-vinyl acetate (EVA) copolymers are
flexible thermoplastic resins. Moldable grades
were develop; d in 1964.

TYPICAL USES
Present and potential uses for these new rubber-like plastics cover a variety of products,
such as molded mechanical goods milk dispenser tubing, syringe bulbs, hospital sheetingand similar hospital and pharmaceutical items.

Others include shower curtains, greenhousecovers, disposable gloves, inflatable toys, andpool liners. Some grades meet Food and Drug
Administration requirements for food packaging.

PROPERTIES
Flexible without plasticizer overFlexibility
a wide range of low and medium temperatures,
including better low temperature flexibility
when compared to vinyls.
Impact strength High, even at extremely low
temperatures.
Resilience Excellent "snap-back.'
High resistance to flex cracking orFlex life
environmental stress cracking.

FORMS :AND METHODS OF FORMING
EVA molding compounds are formed by injection molding, extrusion and blow molding.

17

nents; and other miscellaneous items (i.e. bellows, filters, pipe, tubing, and laboratory ware).

They are used in consumer and household
applications as coatings for frying pans, cooking
utensils, rolling pins.

PROPERTIES
Fluorocarbon resins haveunmatched chemical resistance to most indus-

Chemical resistancetrial chemicals and solvents.

Fluorocarbon reins retain
Thermal stability
useful properties from cryogenic to elevatedtemperatures, exceeding the temperature rangeof all other plastics.
Low coefficient of friction and anti-stick propertiesaFluorocarbon resins have one of thelowest coefficients of friction known for solids
and exhibit unmatched anti-stick characteristics.
FORMS AND METHODS OF FABRICATION

Fluorocarbon resins are applied as powders,
granules or dispersions. They can be molded,
extruded, hot or cold formed, machined, andare also applied as 'coatings.

1.

Miniature, subminiature andmicrominiature terminals, moldedand fabricated from fluorocar-

bons, are used for components

for circuitry in TV, UHF microwave computers and other critical electronic circuits.
Plastic sheet compressionmolded from ionomer resin has
high transparency and flexibility.

2.

Quarter-inch

sheet

is

easilyflexed by girl, indicating use as
face protection for industrial
safety equipment.
3. lonomer can be tailored forskin packaging of hardware items
and other consumer products.
4. Auxiliary gasoline fuel tankfor utility automobile is moldedof nylon. Irregular in shape andmade without seams or joints,
the nylon tank is designed to fit
into compact space below driver's seat. Using nylon, engineers
were able to design tank to meet
unusual space requirements.

5. Woven fabric of nylon monofilament is used for handbags

and shoes in matching colors.
Nylon fabric resjsts attack andstaining by oil, grease and common chemicals.

6. Parylenecoated lithiummetal
granules at left do not reactwith water on which they float.
Unprotected granules at right react instantly and violently.

IONOMERNYLON (POLYAMIDE)

The ionomers are a new family of thermoplastic resins developed in 1964. The term ionomer
was coined to indicate that the polymer con-

Nylon, the generic name for a family of polyamidc resins with related but not identical chemical compositions, is a thermoplastic material
developed in 1938.

tains inorganic as well as organic materials
linked by both covalent and ionic bonds.

TYPICAL USES
Ionomers can he tailored for a very wide variety of end uses; skin packaging applications,

extrusion coatings and laminations for foodpackaging, molded items for housewares, toys,
tool handles, bottles, closures and vials, wireand cable insulation, extruded shapes, tubing
and sheeting. Flat sheeting can he thermoformed info covers, trays and irregular shapes.

PROPERTIES
Ionomers combine
transparency with toughness, especially at low
temperatures and are more resilient than polyTransparent and toughethylene.

Ionomers arc virtually
unaffected by oils and greases. irhey are resistant to bases, dilute acids, hydrocarbons,ketones, alcohols and esters. Resistance toliquid absorption is high by comparison withmany plastic materials of comparable transChemical resistanceparency. Certain grades of ionomers arerecommended for food packaging; meeting therequirements of food additives resulations.
Exceptional corona resistance in electrical insulation.
Tasteless, odorless.

Color

In the natural state it is crystal clear.

This new resin can be readily colored withcomplete uniformity and has a high capacity
level for fillers while retaining serviceable properties.

Ionomers can be heat sealed andcan provide adhesion from a molten state toAdhesionsubstrates, including metals.

FORMS AND METHODS OF FORMING
This plastic is injection molded, blow molded,
extruded as shapes, film, substrate coatings andwire insulation, and thermoformed.

19

TYPICAL USES
Nylon is a familiar material for tumblers, slide
fasteners, faucet washers, gears. As a filament
it is used as brush bristles, fishing lines.

PROPERTIES
Nylon
can be safely boiled and steam sterilized. Also,
freezing temperatures do not adversely effect it.
However, nylon is not recommended for continuous outdoor exposure. It is self-extinguishing.
Nylon is tough,Strong and long wearing
having high tensile, impact and flexural strength.
In part, its resistance to hard blows is due to its
resiliency, allowing it to give a little when hit.
Though the hard, glossy surface of nylon is very
resistant to abrasion, scouring powders and steel
wool should not be used in cleaning.
Nylon is unaffected by
Chemical resistanceall common work-a-day chemicals, greases andsolvents except mineral acids. It is fairly e.isilystained by coffee, tea and colored foods.
Electrical characteristics Very good.
Resistant :o extremes of temperature

Cojor

Nylon varies from transparent toopaque depending on the thinne'ss of the article.
It comes in a range of soft colors.

FORMS AND METHODS OF FORMING
Nylon is available as a molding powder and as
sheets, rods, tubes and filaments.
Finished products can be made by injection,
compression, molding, blow molding, and extrusion.

PARYLENE

PHENOLIC

Parylene is a family of thermoplastic materials
introduced in 1965.

Thermosetting phenolics were developed in 1909.

TYPICAL USES
Sophisticated applications include: insulating
and protective coatings for paper, fabric, ceramics, metals, and electronic parts such as

TYPICAL USES
Automobile distributor heads and insulation,

photo cells, micro-circuits, memory units, andcapacitors; encapsulation of reactive materials;
and ultra-thin pellicles.

PROPERTIES
Parylenes havehigh melting points (500°F.-750°F.) Thermal
endurance in air is moderate, but for short term
(1000 hr.) use, temperatures of about 200°F.

High-temperature resistanceto 240°F. are practical. For long term (10yr.), data indicates that temperatures in therange of 140°F to 175°F. are optimum.
Cryogenic Steel panels coated with parylene
and chilled in liquid nitrogen to 320°F. withstand impacts of more than 100 in.-lb. in a
modified falling ball impact test.
Dimensional stability
Parylene shows out-

standing dimensional stability with respect tochanges in relative humidity.
Chemical resistanceParylenes resist attack
and are insoluble in all organic solvents up to
300°F. They are unaffected by stress-cracking
agents and are also resistant to permeation by

all solvents with the exception of aromatichydrocarbons. Gas and moisture vapor barrier
properties are excellent.
Electrical

Dielectric properties of parylenes
are extremely good. Near absolute zero, one
type of parylene provides the best electrical insulation of any known plastic.
FORMS AND METHODS OF FABRICATION

Parylene can be deposited as a uniform, continuous, adherent film or formed on a surface
treated with a release agent and then stripped
free. Any material that can withstand relatively
high vacuum can be coated.

20 THE STORY OP THE PLASTICS INDUSTRY

Production was approximately 1.1 billion lbs.
in 1967.

telephone handsets, radio and television cabinets,
electrical insulation, washing machine agitators,

appliance parts, molded drawers, tube bases,
bonds for abrasives, brake linings, protective
coatings, juke box housing parts, novelties,
jewelry, pulleys, handles, dials, knobs, laminated wood frame members.

PROPERTIES
Phenolics are hard, rigid,
strong. The average phenolic will withstandStrong and hard

knocks, such as are common with camera housings. Special impact-resistant molding phenolics

can be employed where use

is even more
rigorous. Their smooth, lustrous surface will
give excellent service under severe conditions.

Heat and cold resistantPhenolics have goodheat resistance up to 300°F. and some above.
Mineral and glass reinforced phenolics will perform up to 400°F. continuously. Moreover,they are poor conductors of heat, being cool to

the touch when used as handles for cooking
utensils. They do not support combustion orundergo change from freezing temperatures.
Electrical characteristics Phenolics are excellent insulators. Special low-loss electrical insulating materials are available.
Chemical and water resistance
Water, alcohol, oils, greases and mild acids and common

solvents do not adversely affect phenolic parts.
Where extreme chemical resistance is requireda special chemical resistant type is available.
Phenolics, as a whole, do not absorb water andretain their luster, strength and rigidity.
Color As molding materials they are opaqueand are produced in black, brown, mottled walnut and dark colors. They tend to yellow upon
exposure to light. Colorability distinguishes
cast from molded phenolic. Cast phenolics areproduced in transparent, translucent and opaquecolors, and in variegated effects.

PH EN OXY

TYPES
Phenol-formaldehyde
Molding materials are
considered the "work horses" of the plastics in-dustry, They are combined with various fillers
woodflour, chopped fabric, paper pulp, asbestos, mica depending upon the ultimate use
for which they are intended. These plastics arealso produced as bonding resins, resins for protective coatings, adhesives. Finished products

are made by compression. transfer, plunger
molding; casting; laminating; coatings.
Cast phenolic These are resins cast to form
and are usually machined into finished products.
They are strong, rigid and dimensionally stable,
heat resistant, hard to scratch, water and chemical resistant. They are produced in a wide

range of colors and variegated patterns, likeonyx and marble. They are produced as sheets,
rods, tubes and in special forms.
Phenol-furfuralThis type has most of theproperties of phenol-formaldehyde resins andplastics. It offers high strength, durability, dimensional stability and good electrical characteristics. Dark in color. Molding advantage is
extended flow at low temperatures, fast cure athigh temperatures. It is available as molding
compounds, liquid resins, varnishes and cements. Phenol-furfurals are made into finishedproducts by compression, transfer and injection
molding; low-pressure molding; coatings; impregnating; laminates.
Resorcinol
This type is used primarily as
room-setting adhesives in laminated gear blanks
and laminated wood frame members. Outdoor
exposure is good. Low temperature curing is
an advantage in the lamination of heavy structures with thick sections. Resorcinols come as
solids and liquids and are made into products
by laminating; impregnating; coating; foaming.

FORMS AND METHODS OF FORMING
Phenolics are available as a molding compoundto which different fillers may be added; as pre-forms, boards and blanks; for impregnants,
bonding agents, coatings, foams. Finished products are made by: injection, compression, transfer, plunger molding; casting; laminating.

21

Phenoxies are thermoplastic materials introduced in 1962.

TYPICAL USES
End uses for phenoxy compounds include clear
blow-molded bottles, cosmetic, drug and foodcontainers and other packaging applications:molded electronic parts for computers, electrical appliance housings: sporting goods and battery cases; extruded pipe; and in adhesives :And
coatings.

PROPERTIES
OpticalCrystal-clear, water-white phenoxy

resins can be colored with dyes or pigments
through the full range from delicate transpawnt
tints to opaque colors.
MechanicalPhenoxy exhibits an excellent
balance of high rigidity, strength, hardness, andtoughness, and is a practical engineering material, Parts can be economically and rapidly

produced to meet tight tolerances and to holdtheir shape and size.
ThermalPhenoxy retains its high tensile
strength and rigidity right up to its heat distortion point, Fabricated parts can he used inload bearing applications at temperatures ashigh as 160°F. to 170°F.
Barrier
The permeability of phenoxy, particularly to oxygen, is the lowest of any meltprocessable polymer. Oxygen permeability is
1/20 that of high density polyethylene.
ChemicalPhenoxy is resistant to attack byacids and alkalies, but swells and ultimately
dissolves in solvents. It is also resistant tohydrocarbons, and most household cleaning
compounds.

FORMS AND METHODS OF FORMING
Phenoxy pellets may he blow-molded, injection

molded or extruded with ease. Finished parts
are readily joined by conventional methods.
Phenoxy is also supplied as resins for adhesives

and as resins or in solution form for surface
coatings.

POLYALLOMERPOLYCARBONATE

Polyallomers are a class of crystalline polyolefin polymers prepared from at least two monomers by copolymerization. The resulting polymer chains comprise polymerized segments ofeach of the monomers used
Thermoplastic, piopylene-ethylene polyallomer was developed and introduced in the UnitedStates in 1962.

Polycarbonates are thermoplastics developed

TYPICAL USES
Automobile windlace and cowl panels, pipe

when using an electrically operated device.
Air conditioner housings; handles of electric
tools: power drills, saws, routers, impact

fittings, self-hinged cases and containers, notebook binders, closures, toys, shoe lasts, film andsheet for packaging and vacuum forming.

PROPERTIES
Propylene-ethylene polyallomer combines manyof the best characteristics of crystalline polypropylene and linear polyethylene.
Compared with general-purpose polypropylene, it offers lower brittleness temperature,higher impact strength, less notch sensitivity,and greater melt strength.
It offers better color, lower susceptability toblushing, and better moldability than impactgrade polypropylene. It also possesses superior
resistance to fatigue from flexing ... the "builtin" hinge property.
Compared with linear polyethylene, it offers
superior processability, a higher softening point,

greater dimensional stability and surface hardness, lower and more uniform shrinkages, andlower mold density. It possesses the outstanding dielectric properties common to the polyolefin plastics.

FORMS AND METHODS OF FORMING
Propylene-ethylene polyallomer can be processed by injection molding and extrusion onconventional thermoplastic equipment. Sheetmade of polyallomer is generally superior to

sheet made of other polyolefins for vacuum
forming.

22 THE STORY OF THE PLASTICS INDUSTRY

commercially in 1957.

TYPICAL USES
Polycarbonates are used to provide framelessdesign, where a combination of structural rigidity and outer housing are necessary in one part;and double insulation where a secondary outerhousing is necessary to protect the operator

wrenches, hedge clippers; home appliances:electric can openers and shavers; street light
globes; lighting diffusion panels; lamp coatings;

sunglass lenses and frames; telephone finger
wheels; fishingreels; covers for baby foodwarmers and baby bottles; glazing; coffee pots;
electric.] connectors; blood oxygenators; rocket
launcher handles; water pump impellers; electric knife handles.

PROPERTIES
MechanicalExceptionallyhighimpactstrength, heat resistance, rigidity, dimensional
stability. Parts made from poiycarbonate resin
can take hammer blows without shattering andcan withstand small caliber bullet force without
being pierced or shattered. Polycarbonates canalso be reinforced with glass fibers for evengreater dimensional stability and rigidity.
Heat resistance
Polycarbonates maintaintheir stability at operating temperatures up to
240°F. Self extinguishing.
Electrical Good,
Chemical resistanceResistant to oil. Stain
resistant. Non-corrosive.
Color
Transparent. Good colorability andgloss.

FORMS ANT) METHODS OF FABRICATION
Polycarbonate resin is primarily a molding material. It may also take the form of film, extrusions, coatings, fibers or elastomers.

1. A heavy metal frame for thisBraille typewriter has been replaced with a one-piece, multipart frame molded of highstrengthphenolic.

Frame

is

molded to tolerances as accurate as .003 to permit carriage
and other moving parts to function with fingertip ease.
2.

Durablecarrying

caseofpolyallomer provides portability
for industrial gas mask. Lightweight 2 lb. case Is molded in
one piece and includes back,front, hinges, handles and snap

itclasps. Case is strong enough tohold mars weight, resilient
enough to resist impact andtracking. Integral tinges havebeen tested 12 million times
without cracking.

Low shrinkage and dimensional stability give phenoxy the3.

edge in molding the precisionframes necessary in these electronic sub-assemblies, known as
diode sticks.

3

4. Visor cl polycarbonate provides excellent optical properties and high strength protection
for astronaut during walk In
space. Polycarbonate plastic wasstrongest transparent material
tested.
Polyester reinforced fiber
glass canoe Is of sandwich construction with high strength and5.

low weight. A layer of polyurethane foam gives 150 pound
flotation in excess of hull weight.

POLYESTERPOLYETHYLENE

Polyesters are thermosetting materials. Developed in 1942, they reached a production levelof about 495,000,000 lbs. in 1967.

Polyethylene is a thermoplastic material. Developed in 1942, this plastic reached a production level of about 3.8 billion lbs. in 1967.

TYPICAL USES
Polyester resins are used to impregnate cloth

TYPICAL USES
Polyethylene is familiar as the material for
flexible ice cube trays, tumblers, dishes, car-or mats of glass fibers, paper, synthetic fibers,
cotton and other fibers in the making of rein-

forced plastics for use in boats, automobile
bodies, pipe, luggage, aircraft components, in-terior partitions and skylights or translucent
roofs for buildings, scuff plates, film developing

trays. They are used in cast form for jewels
and lenses, and are combined with acrylics toproduce peatlescent buttons that resist heat.

PROPERTIES
Adaptability to large parts
Products up to
500 sq. ft. in area are practicable because they
can be formed under low or no pressure and at
low or room temperatures.
Strength
These plastics are strong and tough.
The strength, rigidity or flexibility of laminatesand moldings may be varied through the QP1eC"
tion of the reinforcing material. Polyesters
have a superior surface hardness.
Chemical and water resistant
Polyesters arehighly resistant to most solvents, acids, bases
and salts. They also offer a low water absorption rate and good weathering qualities.
These plastics have highdielectric qualities.
Colorability These plastics can be made in arange of bright and pastel colors.
Electrical properties

FORMS AND METHODS OF FORMING
Polyesters are produced as liquids, dry powders, premix molding compounds, and as cast
sheets, rods and tubes. A special fire-retardantgrade is available. Premix compounds are madefrom these basic resins to produce compression

boys and rigid and squeezable bottles, pipe andtubing, bags for candy and food products, raincapes, meteorological balloons, dry cleaners'
bags for clothing, artificial flowers, greenhouses,
silo covers, insulation, freezer bags, toys, mois-

ture barriers under concrete and in walls, andcoated paper for freezer wrap. Many of theseproducts can be made with low, medium, or
high density polyethylene, depending on theflexibility or rigidity required.
Some formulations are specifically approvedby U. S. Food and Drug Administration regulations. Semi-conductive and vulcanizable polyethylene has recently been developed for outer
jacketing on communications and power cables.
Copolymers such as ethylene-vinyl acetate andethylene acrylate are also available.

PROPERTIES
Depending on density,polyethylene is flexible or rigid. Either form isvery resistant to breakage. Its surface is hardenough to withstand normal use but abrasive
cleaners should be avoided.
Heat and cold resistantThis plastic canwithstand temperatures down to 100°F. without becoming stiff and brittle. Also, some formulations may be subjected to boiling waterand sterilization. It should not be used over anopen flame or in a hot oven.
Electrical characteristics
Polyethylene offers
excellent insulating properties.
Strong and flexible

and transfer molded parts for automobiles,

Odorless, tasteless.

household utensils, electrical appliances, fix-

Resistant to water and weatheringtures and tools.

ene is moistureproof, but allows passage ofoxygen. Recommended for some outdoor ap-

They are formed by reinforcing, molding,casting, impregnating, premixing.

24 THE STORY OF THE PLASTICS INDUSTRY

plications.

Polyethyl-

Chemical resistant This plastic is highly resistant to chemicals and is unaffected by foodacids, household solvents and by short contact
with cleaning fluids.
Color and appearanceThis wax-like plastic
is available as a clear transparent, translucent
or opaque material. Made in a range of colors.

FORMS AND METHODS OF FORMING
Polyethylene is available in pellet form, powder, sheet, film, filament, rod, tube and foamed.

It may be made into finished articles by injection, compression, blow molding; extrusion,
calendering, coating, casting, vacuum forming.

Other properties

Polyimides possess excellent

bearing qualities, resist radiation, exhibit low
out-gassing in high vacuum, and maintain their
excellent properties at cryogenic temperatures.
FORMS AND METHODS OF FABRICATION
Polyimides are supplied in the form of finished
precision parts, as wire enamel, laminates, adhesives, film, and as the resin bond in diamondabrasive products. Because polyimides do not
melt, fabricated parts are made by machining,
punching or by direct forming techniques.

POLYPHENYLENE OXIDEPOLYIMIDE

Polyimides, a new class of non-melting plastics,
were announced in 1962. They share the linear

structure of the thermoplastics, yet, like thermosetting plastics, they have no measurable
melting point.

TYPICAL USES
Polyimides are used in a wide range of applications in extreme environments at both highand low temperatures. Examples are aerospaceparts, valve seats, bearings, seals and retainerrings. Industrial applications include compressor vanes, piston rings, bearing separators, connector inserts, and relay actuators. A polyimide
film is produced for cable wrap, motor slot
liners, formed coil wrap, flexible circuits, tapes,

hose and tubing. A polyimide enamel is produced for wire insulation, and polyimide laminates and adhesives are also available.
PROPERTIES
Excellent. Polyimides retain
Heat resistancea significant portion of their room temperature
mechanical properties up to at least 750°F. andcan be used continuously in air at 500°F. without any loss of properties.
Very good.
Electrical
Excellent frictional characteristics and very good wear resistance.
Wear resistance25

Polyphenylene oxide resins are thermoplastics
developed in 1964.

TYPICAL USES
Polyphenylene oxides have a wide range of applications as electrical insulating parts battery
cases, coil forms, computer modules steriliz-able medical and surgical instruments, house.
hold appliances exposed to hot water andplumbing equipment, including valves, pumps
and plumber's brass goods.

PROPERTIES
Color

Presently opaque, beige.

Impact strength

Excellent.

Polyphenylene oxide maintains a high level of strength and rigidity overa broad temperature range.
Dimensional stability
Parts molded of polyphenylene oxide withstand large loads for long
periods of time without significant change indimension. Parts possess high modulus andTensile strength

low creep.

Polyphenylene oxide has a wide
temperature range, a brittle point of approximately 275°F. and a heat distortion point ofThermal

375°F. at 264 psi,Electrical

Polyphenylene oxide has excellent
continued on page 27

1. Blow-molded polyethylene bottles for industrial, automotive
and chemical specialties arecolorful, easy to handle, chemically resistant and often serve
as self-dispensers.

2. High voltage submarine cableis protected with extruded polyethylene insulation, which ensures high dielectric strength,
low dielectric loss, and excellent

stability of electrical and physical properties when in contact
with sea water.

3. Gears made of polyimide in
two different aircraft anti-collision lighting assemblies operatesatisfactorily at very high ambient temperatures. These gears
are strong enough for the hightoads encountered, while operating continuously at 300°F. andhigher.

Sterilizable mediol equipment made from polyphenyleneoxide is autoclavable and low in
4.

cost.

Enlarger printer for amateur
molded fromasbestos - reinforced polypropylene, a stiffer, more heat resistant material without sacrificing

5.

photographers ispolypropylene's

surfacehard-

ness, resistance to flexural fatigue, impact strength and resistance to chemicals and stresscracking.

B.

Refrigerator door liners arethermoformed from a single
sheet of highimpact styrene.

withstand slam-bang impacts of clay-in and day-out servThey

ice at refrigerator temperatures.

Animated toys benefit fromthe unusual toughness of extra
high impact polystyrene.
7.

Subminiature printed circuit
card-edge connector at left, andrack-and-panel connector at rightare precision mulded from poly-B.

sulfone.

1dielectric properties maintained over a wide
temperature and frequency range.
Hydrolytic stability Polyphenylene oxide resists steam, aqueous chemicals, acids and bases.
FORMS AND METHODS OF FABRICATION
Polyphenylene oxide resins are fabricated by all
conventional techniques including extrusion
and molding.

POLYPROPYLENE

Polypropylenes are thermoplastic materials first

introduced if:: the United States in 1957. Production of polypropylene in 1967 reached
620,000,000 lbs.

TYPICAL USES
Safety helmets, pipes and fittings, valves, packaging film and sheets, sterilizable bottles, wireand cable insulation, battery boxes, refrigerator
parts, waste baskets, tubs for washing machines,
flexible hinges, housewares and household appliance parts.

PROPERTIES
Flex life Polypropylenes have excellent flex
life.

In general, polypropylene is an
Mechanicaloutstanding electrical insulation material. It hasvery low dielectric constant, essentially unaffected by frequency or temperature over ranges
tested. It shows a low loss factor.
The surface hardness andSurface hardness
scratch and abrasion resistance of polypropylene are superior to other low-cost polymers.

FORMS AND METHODS OF FORMING
Polypropylene can be processed by injection
molding, blow molding and extruded on conventional thermoplastic equipment. Films madeof polypropylene may be heat-sealed with thesame equipment used for polyethylene and canbe laminated to paper, cloth or aluminum.
Polypropylene is also produced as a foam
plastic.

POLYSTYRENE OR STYRENE

serae impact or flexing. Abrasives should be
avoided when cleaning. For higher strength
aml impact resistance, glass-filled types area wail able.

Polystyrene is a thermoplastic. Developed in
1938, its production totaled an estimated2,550,000,000 lbs. in 1967.

TYPICAL USES
Kitchen items, refrigerator food containers,
toys, battery cases, instrument panels, wall tile,
portable radio housings, premiums, are typical
products made from polystyrene or styrene.
Styrene copolymers and terpolymers areavailable which offer greater toughness and impact properties, higher heat resistance, or other

YORMS AND METHODS OF FORMING
Polystyrene or styrene is available as molding

powder and granules, sheets, rods and othershapes, foamed blocks, as liquid solutions andadhesives, coatings.

Finished products may be made from polystyrene or styrene by injection, compression
molding and by extrusion, laminating and machining.

special qualities.

PROPERTIESPolystyrene
Optical qualities, color, texture
or styrene is available as a clear transparent,
translucent or opaque material in a rainbow ofcolors.

It can be produced with a smooth

POLYSULFONE

Polysulfones are thermoplastic materials developed in 1965.

satiny surface or a special texture.

TYPICAL USES

Tasteless, odorless.
Electrical qualities

Polysulfone finds wide use in appliance housings; "under-the-hood" automotive components;
hand power tool housings; computer parts;
switches; circuit breakers; extruded pipe, sheeting, and wire coatings; and in structural bonding and laminating formulations.

Polystyrene or styrene hasvery good all-round dielectric properties.
Water and weather resistance Articles made ofpolystyrene or styrene hold their dimensions wellunder conditions of normal use. It should not
be exposed to continued outdoor use. The material's water absorption rate is low.
Resistance to heat and cold Polystyrene or
styrene is not harmed by continuous use at foodfreezer temperatures. It can be subjected, forshort periods, to heat approaching the boilingpoint of water. If greater heat resistance isdesired, a special type may be used. This plastic
will burn slowly if subjected to a direct flame.
Most foods, drinks andChemical resistantusual household acids, oils, alcohol, vinegar,
have no effect on polystyrene or styrene. This

PROPERTIES
Resistant to extremes of temperature

Polysulfone possesses the highest use temperature ofany melt processable thermoplastic and very
low creep under toad. It is inherently selfextinguishing. It maintains a high degree of its
mechanical and electrical properties in continuous service at temperatures ranging from150°F. to over 300°F.
Color Supplied in a variety of transparent andopaque colors, polysulfone can be dry-coloredwith certain dyes.

is not true, however, of citrus fruit rind oil,

Mechanical strengthcleaning fluids, gasoline, turpentine, nail polishand remover, which will harm the material.

sile strength and modulus and a good stressstrain behavior pattern typical of rigid ductile

Polystyrene or styrene is hard andrigid and withstands ordinary household use.
It is not recommended for articles subject tomaterials.
Chemical and solvent resistance Polysulfone
is highly resistant to mineral acid, alkali, andStrength

28 THE STORY OF THE PLASTICS INDUSTRY

Polysulfone has high ten-salt solutions. Resistance to detergents, oils
and alcohols is good even at elevated temperatit:AN under moderate levels of stress.

Electrical properties
Electrical properties ofpolysulfone are excellent over a wide temperature range and even after immersion in wateror exposure to high humidity.

FORMS AND METHODS OF FORMING
Polysulfone resins may be used as adhesives
and can be fabricated by extrusion, injection
molding, blow molding and thermoforming.
Formed parts can be processed by all standard
machining methods, joined by solvent or heatsealing techniques, and surface decorated with
ease.

.1

PROPERTIESSOLID MATERIALS:

Tough and shock resistant Elastomeric types
have unusual abrasion and tear resistance.
Adhesion
Isocyanates are among the few
substances effective for adhering synthetic rub-ber to synthetic fibers in the manufacture oftires, and for uniting rubber with metals andceramics. Urethanes are used as adhesives forbonding leather to leather, foams to various
substrates, etc.

Resistance to chemicals and other agents The
cured plastics are remarkably resistant to a wide
variety a deteriorating agents, such as common
chemicals, including organic solvents, and pe-troleum products. Water-, moisture-, rot- andvermin-proof. Special polymers can be compounded to be flame - resistant.
FOAMED MATERIALS:

POLYURETHANE OR URETHANE

Flexible foams can be made in a broad rangeof firmness and resilience and in varying densi-

Industrial interest in urethane plastics in thiscountry has grown rapidly in recent years.
Urethanes were introduced commercially in
1954.

TYPICAL USES
These versatile materials have been used forsome time abroad for a variety of purposes andin many different forms, such as flexible to rigid
foams, solid elastomers and plastics, coatings
for wood, metal, wire and textiles, adhesives,
bristles.

Urethane foams are favored for cushioning,
mattresses, insulated clothing, padding, toys,
packing, rug underlays, sponges, mats, crashpads, lightweight structural parts and applianceinsulation.
Solid articles formed by molding, extrusion or

casting include elastic printing rolls, abrasive
wheels, cable insulation, automotive parts, bristles, tire treads, and airplane structures.
Urethane coatings impart outstanding protec-

ties. These foams have properties suitable forcushioning, shock- and sound-absorption, andheat insulation. Rigid foams are beginning tofind large use as thermal insulation. Because
urethanes can be foamed-in-place, their areasof use are greatly enhanced.

FORMS AND METHODS OF FORMING
SOLID TYPE:

Fabrication is generally carried out startingwith two reactants; polyisocyanate and polyol.
These raw materials are supplied as liquid or
solid organic di-isocyanates, to be combinedwith special polyesters or polyethers or as prepolymers (partially reacted). Final articles canbe extruded, molded, calendered, or cast in
shapes as desired. They are then cured to final
form.
FOAMED TYPE:

The raw materials are polyols, polyisocyanates,

water and catalyst mixtures. Foams can betive and decorative effects to wood, metals, rub-made by either a prepolymer or one-shot proc-

ber, textiles, concrete, paper, leather, plastics
and many other products.

ess, in both slab stock and also in molded29

forms.

SILICONE

VINYL

Silicones were commercialized in the early

The vinyls, which are thermoplastic materials,
are produced in seven major types. Introduced
in 1927, all the vinyls were estimated as totaling

1940's.

2.8 billion lbs. in 1967.

TYPICAL USES
The big outlets for silicones are in the electrical industry where they are used for coilforms, switch parts, induction heating apparatus, as insulation for motors and generator
coils, and in power cables.
In thermoplastic and thermosetting resin
systems silicone coupling agents are used tostrengthen the bond between glass fibers or min-eral fillers and resins. As little as 0.001% silicone (based on total weight) can double thestrength of glass/reinforced thermoplastics.

PROPERTIES
Silicones exhibit high heat
Heat resistantstability. Silicone insulation has shown itself
highly stable up to 350°F to 590°F. dependingon whether it is used with glass fiber, mica,
or asbestos.
Silicones have very good
Electrical qualities
dielectric properties, particularly after exposure

to moisture and elevated temperatures. They
offer a low power factor over a wide frequency
range.

Chemical and water resistant

Silicones arewater repellent, weather resistant and highly resistant to mineral acids, and also corrosive salt
solutions.

FORMS AND METHODS OF FORMING
Silicones are available as molding compounds,
resins, coatings, greases, fluids and as silicone
rubber.
They may be made into finished articles by:compression and transfer molding, extrusion,
coating, calendering, impregnating, laminating,foaming, casting.

30 THE STORY OF THE PLASTICS INDUSTRYTYPICAL USES
The vinyls are produced in several forms:
flexible or elastomeric, inflexible or rigid, cellu-

lar or foam.
They are familiar as raincoats, garment bags,
inflatable water toys, shower curtains, upholstery, draperies, garden hose, wire and cable insulation, phonograph records, clear blow-Molded packaging containers, gaskets, weatherstrip,
electric plugs, floor and wall covering andcoated materials.

PROPERTIES
Strong and abrasion resistant
All types ofvinyls are tough and strong, though only theflexible types can be bent back and forth without weakening or tearing. The surface of all
vinyls resists the abrasion of normal use andspecial types are available with very high wear
resistance. Abrasive cleaners should not beused.

Chemical and water resistantVinyls, withthe exception of some non-rigid types, are unaffected by prolonged contact with water, oils,
foods, common chemicals and cleaning fluids
such as gasoline and naphtha. They should all
be kept away from chlorinated solvents, nailpolish and remover, and moth repellents. Vinyls
enjoy a very slow rate of water absorption.

Resistance to heat and cold Vinyls in generalwithstand continuous exposure to temperatures
up to 130°F., the range usually encountered inhousehold operation. Flexible types and fila-

ments are unaffected by higher temperatures.
On the cold side, vinyls perform satisfactorily
at food freezing temperatures. Vinyls are slow
burning; certain types self-extinguishing. They
should be kept from contact with direct heat.
Wide color range
Vinyls are produced inclear form and in a wide range of colors which1. Trim straight lines of modern
furniture are assured by use oflong-lasting

polyurethane foamcushions, which will retain theirshape despite long wear, while
offering exceptional seatinw com-

fort.
2.

Flexible "concrote"a new

construction material that looks

like concrete, but can be bent
like rubber. The base compoundis a spacedeveloped silicone
rubber. The material is used asa topping for highways, patios,
It withstands
the ravages of weather, water,
swimming pools.

freezing and cracking.
3. Lightweight, weather resistant
polyvinyl chloride is used In
modern homes for gutters, down
spouts, leaders and siding.
4. Vinyl-chloride acetate sheeting finds use as liners for ponds,
reservoirs and irrigation ditches,
effectively preventing loss ofwater due to seepage.

5. Exterior vinylmetal laminates
decorate this laboratory building.

Application involves vinyl

laminated to aluminum with asandwich of polyurethane foam
and gypsum board. This board
Is,in turn, laminated with in.

tenor vinyl which becomes theinterior wall.

6.j Young traveler rides in luxurious comfort on a padded carseat made from soft vinyl foam.

may be clear, translucent or opaque. They may
be printed or embossed.
Weathering
Vinyls are generally recommended for indoor use, though special types
are made for use out-of-doors.
Vinyls generally have excellent electrical properties.
Electrical qualities

plications.

It is also produced as film andshoring.
Available in rigid
and flexible form. It is familiar in shower curtains, rainwear, phonograph records, shoe soling, wire insulation, coated fabrics, surface
Polyvinyl chloride-acetate

coatings.

This vinyl may bemade into both flexible and rigid form. It isfamiliar as an extruded monofilarnent which is
woven into upholstery fabric and screening. It
Polyvinylidene chloride

TYPES
Polyvinyl acetalThis type vinyl falls into
three groups: polyvinyl formal, polyvinyl acetaland polyvinyl butyral. Polyvinyl butyral is familiar as the interlayer for safety glass.
Polyvinyl acetate This, vinyl material is odorless and tasteless, slow-burning, colorless, insoluble in water, fats, tvaxes and aliphatic hydrocarbons. It is used for heat-sealing films,
flashbulb linings, paints, adhesives.
Polyvinyl alcoholThis vinyl is characterized
by its imperviousness to all water insoluble solvents and gases, animal and vegetable oils. It isstrong and abrasion resistant. It is used in paper
coating and sizing. Cast polyvinyl aloe of isis also used as pipe and tubing.

FORMS AND METHODS OF FORMING
Polyvinyl acetal is available as molding pow-der; sheet, rod and tube. It can be formed by:molding, extruding, casting, calendering.
Polyvinyl acetate is available as granules, filmforming emulsions, adhesives.
Polyvinyl alcohol is available as molding pow-

der, sheets, film, tube and rod. It. can be formed
by: molding, extrusion, casting.

used as a mold release in molding polyester

Polyvinyl carbazole is available as powder,
lumps, film. It can be made into articles by_ :resins with glass fiber for airplane parts, boats,

compression and injection molding, casting.

etc. Internally plasticized polyvinyl alcohol isused as a water soluble film for packaging soaps,
detergents, dyes.

Polyvinyl chloride is available as resins, latices,

Polyvinyl carbazole

This vinyl is characterized by its combination of desirable electricalproperties. Typical applications are structuralcomponents for low-loss electrical assemblies.
Polyvinyl chloride
This vinyl can be madein a wide range of flexibility. It offers unlimited

colors, toughness and high resistance to acids,
alkalies and alcohol. It has wide use as pipeand extruded profiles, wire and cable insulation,
work gloves, flooring, upholstery and foam ap-

32

THE. STORY OF THE PLASTICS INDUSTRY

coatings, organosols, plastisols, compounds. It
can be made into finished products by molding,
extrusion, calendering.
Polyvinyl chloride-acetate is available as molding powders, organosols, plastisols, sheets, rods,
tubes. It can be made into finished products
by compression, injection and slush molding,calendering, casting, extrusion and as coatings.
Polyvinylidene chloride is available as molding
powder, sheets, rods, tubes. It can be madeinto products by injection, compression, transfer molding, extrusion, casting.

Processing

Plastics
PLASTICBLOW MOLDING!MUM PA ISON.
MOLD CORN

Blow molding is a method of forming used withthermoplastic materials.

MOLD CLOSEDa$OME BLOWN

fINISNIO KITTLE
111140100 PROM MOLD

Basically, blow molding consists of stretching and then hardening a plastic against a mold.

There are two general methods of doing thistype of thermoplastic molding: the direct

BLOW MOLDING

method and the indirect method, encompassing
several variations of each.
In the direct method, a gob of molten ther-

moplastic material is formed into the roughshape of the desired finished product. This
shape is then inserted in a female mold and air

blown into the plastic, as into a balloon, toforce it against the sides of the mold. The
formed material is then cooled before removalfrom the mold.
In the indirect method, a thermoplastic sheetor special shape is first heated, then clamped
between a die and cover. Mr pressure forced

PLASTIC

between the plastic and the cover forces thematerial into contact with the die, which has

CALINDIRTD PLASTIC UNITINGOR FILMthe contour desired in the finished product. The

plastic is cooled before removal from contact
with the die.

TARP 00/00

SMELTING

SOUL/CALENDERINGCALENDERING

Calendering can be used to process thermoplastics into film and sheeting, and to apply aplastic coating to textiles or other supporting
materials. Film refers to thicknesses up to and33

including 10 mils, while sheeting includes thicknesses over 10 mils.

In calendering film and sheeting, the plastic
compound is passed between a series of threeor four large, heated, revolving rollers whichsqueeze the material between them into a sheet
or film. The thickness of the finished material
is controlled by the space between the rolls. The
surface of the plastic film or sheeting may besmooth or matted, depending on the surfacing
on the rollers.
In applying a plastic coating to a fabric orother material by the calendering process, thecoating compound is passed through two top
horizontal rollers on a calender, while the uncoated material is passed through two bottom
rollers, emerging as a smooth film which is anchored to the fabric when fabric and.film passbetween the same rolls.

COATING/11,
Thermosetting and thermoplastic materials may
both be used as a coating. The materials to becoated may be metal, wood, paper, fabric,leather, glass, concrete, ceramics or otherplastics.

Methods of coating are varied and include
knife or spread coating, spraying, roller coating, dipping, and brushing. Calendering of afilm to a supporting material, described undercalendering, is also a form of coating. A new
method for applying plastics to metals is called
the fluidized bed process.

In spread coating, the material to be coatedpasses over a roller and under a long blade or
knife. The plastic coating compound is placedon the material just in front of the knife, andis spread out over the material. The thicknessof the coating is regulated by the speed at which

CASTING

Casting may be employed for both thermoplastic and thermosetting materials in making
special shapes, rigid sheets, film and sheeting,rods and tubes.
The essential difference between casting andmolding is that no pressure is used in casting
as it is in molding.
In casting, the plastic material is heated to a
fluid mass, poured into either open or closed
molds, cured at varying temperatures depending on the plastic used, and removed from thethe material is drawn under the knife, and theposition of the knife.

In roller coating, two horizontal rollers areused. One roller picks up the plastic coating
solution on its surface Sand deposits it on thesecond roller which, in turn, deposits the coating solution on the supporting material.

A plastic coating may also be applied byspraying it through a spray gun or by brushingit over the material to be coated as in silk
screen work. Articles to be coated may also be
dipped into a solution of plastics until the desired thickness of coating is achieved, and thendried.

molds,

Casting of film (and some sheeting) is doneon a wheel or belt, or by precipitation in achemical bath.

In the case of wheel or belt casting, theplastic is spread to the desired thickness on thewheel or belt as it revolves or moves and as thetemperature is increased. The film is then driedand stripped off.

COMPRESSION MOLDING

Compression molding is the most common
method of forming thermosetting materials. It
is not generally used for thermoplastics.
Compression molding is simply the squeez-

ing of a material into a desired shape by application of heat and pressure to the material
in a mold.
34 THE STORY OF THE PLASTICS INDUSTRY

1

Plastic molding powder, mixed with suchmaterials or fillers as woodflour, cellulose andasbestos to strengthen or give other added qualities to the finished product, is put directly into
the open mold cavity. The mold is then closed,pressing down on the plastic and causing it toflow throughout the mold. It is while the heatedmold is closed that the thermosetting material

COMINGCOATINGI KNiff

COMPOUND

COATED WEISHUT TO SE
COATED

undergoes a chemical change which permanently hardens it into the shape of the mold.
The three compression molding factors pressure, temperature and time the mold is closed
vary with the design of the finished article andthe material being molded.

MTN
110U

SUPPORTSUPPORTING

CHANNELIOWACOATINGEXTRUSION
MOLD PlUNGIRGUIDE PIN

Extrusion molding is the method employed toform thermoplastic materials into continuous
sheeting, film, tubes, rods, profile shapes, fil3ments, and to coat wire, cable and cord.

MOLDED
PLASTICIn extrusion, dry plastic material is first
loaded into a hopper, then fed into -a long beating chamber through which it is moved by theaction of a continuously revolving screw. At
the end of the heating.- chamber the molten
plastic is forced out through a small opening
or die with the shape desired in the finishedproduct. As the plastic extrusion comes fromthe die, it is fed onto a conveyor belt where it

MOW CAVIETCOMPRESSION MOLDING

is cooled, most frequently by blowers or by immersion in water.

In the case of wire and cable coating, theMINDING POWDIP

thermoplastic is extruded around a continuing
length of wire or cable which, like the plastic,passes through the extruder die. The coatedwire is wound on drums after cooling.
In producing wide film or sheeting, the plastic is extruded in the form of a tube. This tube
may be split as it comes from the die and thenstretched and thinned to the dimensions desiredin the finished film.
In a different process, the extruded tubing is
inflated as it comes from the die, the degree of
inflation of the tubing regulating the thicknessof the final film.

35

AMCNAN,C1 SC./ W

EXTRUSION MOLDINGIn addition, rigid sheets can be fabricated
FABRICATING

Fabricating covers operations on sheet, rod,
tube, sheeting, film and special shapes to makethem into finished products. The materials may
be thermosetting cz thermoplastic.
Fabricating divides into three broad categories machining; cutting, sewing and sealing of
Elm and sheeting; and forming.
Machining:
Machining is used on rigid sheets, rods, tubes

and special shapes. The various operations in-clude grinding, turning on a lathe, sawing,reaming, milling, routing, drilling, tapping.
Cutting, sewing, sealing of film and sheeting:In this category of fabricating fall all the operations involved in fashioning plastic film andsheeting into finished articles like inflatabletoys, garment bags, aprons, raincoats, luggage.

For all these articles, the film or sheetingmust first be cut to pattern. This cutting may
be done in a press by a power-driven handoperated knife or by other methods.
It remains to join the various pieces of film.
This may be done by sewing or heat sealing.
Cements are rarely used in fabricating film.
Forming:
In working with flexible thermoplastic sheets,the first step is usually the cutting or blanking
out of sections roughly approximating the dimensions of the finished article. This blankmay be beaded for added strength, creased andfolded into final form a box, for example.
Or deep drawing may be employed, using maleand female molds to shape the plastic blank.
Rigid sheet may also be molded to final form.

There are a number of methods of thus shaping a sheet. In vacuum forming or molding,the heated sheet is damped to the top of afemale mold and either drawn down into themold by vacuum or forced down by air pressure. In snapback forming, the heated sheet isdrawn into a vacuum pot and a male mold lowered inside the bubble formed by the sheet. As
the vacuum is released the hot sheet snaps backagainst the male mold.

36 THE STORY OF THE PLASTICS INDUSTRY/

into finished products by welding them together

as in thermoplastic structural products. These
items include hoods, veining systems, duct
work, tank linerr4. -storage tanks, machinery
covers, and other allied products.
The welding torch itself is perhaps the mostimportant piece of equipment used in thisprocess. There arc t.vo basic types of torches
available which accomplish this procedure satisfactorily. The first and more popular is thetorch which heats the welding gases electrically.

The second type uses an open flame of either
acetylene or propane gas which transfers itsheat to a coil through which the welding gas
is passed.

Standard procedures as established by the in-dustry should be utilized to evaluate welding
performance of thermoplastic structures.

FINISHING

The finishing of plastics includes the different
methods of adding either decorative or functional surface effects to a plastic product.
Film, sheeting and coated materials:
These forms of plastics may have the textureof their surface changed, either during process-ing or after, by being pressed against a heatedroller or mold that is embossed with a pattern.
Colorful patterns may also be printed on thesurface of film, sheeting and coated material
either by letter press, gravure or silk screening.
Rigid plastics:

There are a wide variety of methods of add-

ing decorative effects to the surface of rigid
plastic parts. One is metal plating, accomplishedthrough metal spraying, vacuum deposition or
metal dusting and painting.
Other means of decorating involve stamping
the finished product, printing by silk-screen or
offset, engraving, etching or air blasting.
Molded Products:
Decorative textures on molded products areoften achieved by incorporating them into themolds.

HIGH-PRESSURE LAMINATING

Thermosetting plastics are most generally usedin high-pressure laminating which is distinguished by the use of high heat and pressure.
These plastics are used to hold together the reinforcing materials that comprise the body ofthe finished product. The reinforcing materials
may be cloth, paper, wood, fibers of glass.
The end product of high-pressure laminating
may be plain flat sheets, decorative sheets as incounter tops; rods, tubes or formed shapes.

HEAD

tutu., ccc

stivdtrili ttttttt

ttttttttttttttt

NEMEC

nr

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ITS

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tAIIIINff

SUPS,,,pylvwsissi
SEE

Whatever the final shape, the first step in-1141

high-pressure laminating is the impregnating of
the reinforcing materials with plastics.

:100 PEll

UPWARD /SETS USE t

In producing a flat surface, impregnatedsheets are stacked between two highly polishedsteel plates and subjected to heat and high pressure in an hydraulic press which cures the plastic and presses the plies of material into a single
piece of the desired thickness. In making highpressure tubing, resin-treated reinforcing sheets

HIGHPRESSURE LAMINATING

are wrapped, under tension and/or pressure,around a heated rod. The assembly is thencured in an oven. In producing formed shapes,
the reinforcing material is cut into pieces that
conform to the contour of the product, fitted
into the mold and cured under heat and pressure.
MO MOPPEDMOLDED PIECEINJECTION MOLDING

Injection is the principal method of forming
thermoplastic materials. Modifications of theinjection process art sometimes used for ther-

GATE

'PRUE

NOZZLE(Mina

mosetting plastics.

In injection molding, plastic material is put
into a hopper which feeds into a heating chamber. A plunger pushes the plastic through thislong heating chamber where the material issoftened to a fluid state. At the end of thischamber there is a nozzle which abuts firmly
against an opening into a cool, closed mold.
The fluid plastic is forced at high pressure
through this nozzle into the cold mold. As soon

37

INJECTION MOLDINGPLUNGIR

as the plastic cools to a solid state, the moldopens and the finished plastic piece is ejectedfrom the press.
The problem with injection molding of thermosetting materials is that, under heat, theseplastics will first soften, then harden to an infusible state. Thus it is essential that no softened thermosetting material in the heating
chamber be allowed to remain there longenough to set.

Jet molding, offset molding and molding
using a screw-type machine overcome this problem by liquefying the thermosetting plastic material just as it goes through the injection nozzle
into the mold, but not before.

Reinforced plastics offer exceptionally highstrength with low weight. Also, they lend themselves to easy, economical fabrication, requiring relatively little pressure and heat for curing,and employing types of molds and other equipment that represent a fraction of the investment
cost for metal fabricating dies and machinery.

Thus, they make possible considerably larger
plastics products.
A number of different techniques may be employed in the production of reinforced plastics.
In making formed shapes, impregnated reinforcing material is cut in accordance with theshape of the finished product into one piece ora number of pieces. The pattern or patterns areplaced on a male mold in enough volume togive the final thickness and form. Molding is

PULP MOLDING

completed in heated, mated dies. A single moldmay be used. The impregnated reinforcing material may be laid up on a male mold, inserted
in a rubber bag from which all air is withdrawn
so the bag presses around the layup, and cured

Thermosetting plastics are used in pulp molding.
In this process a porous form, approximating
the shape of a finished article, is lowered into atank containing a mixture of pulp, plastic resins

in an oven. If a female mold is used, a diaphragm is placed over the end of the mold sothat when air is withdrawn from within themold, the diaphragm is drawn down inside themold to press against the layup of resin im-

and water. The water is drawn off through theporous form by a vacuum. This causes the pulp

and resin. mixture to be drawn to the form
and adhere to it. When a sufficient thicknessof pulp has been drawn onto the form, it isremoved and then molded into final shape.

pregnated materials.

In producing a continuous laminate, a webof reinforcing material passes through a bathof plastic resin, between rolls or under wiper
bars that remove excess resin, and then between

sheets of cellophane or coated paper. Thus
protected, top and bottom, the material goes
through the curing oven. After curing, the cellophane or paper is stripped off.

REINFORCING

Reinforced plastics mostly employ thermoset

ROTATIONAL MOLDING

plastics, though some thermoplastics are used.
Reinforced plastics differ from high-pressure

laminates ia that very low or no pressure isused in the processing. The two methods areThis technique is used to fabricate hollow, one-alike in that in both, the plastic is used to bind
together the cloth, paper or glass fibers reinforcing material used for the body of the product. The reinforcing materials may be in sheet
or mat form, and their selection depends on thequalities desired in the end product.

from polyethylene powders.

38 THE STORY OF THE PLASTICS INDUSTRY

piece flexible parts from vinyl plastisols or
Essentially, rotational molding consists ofcharging a measured amount of resin into a
warm mold which is rotated in an oven about
two axes. Centrifugal force distributes theplastic evenly throughout the mold and the heat

melts and fuses the charge to the shape of thecavity. After removing and cooling the mold,the finished part is extracted. Rotational molding is particularly suited to the production ofvery large parts, size being limited only by thecapacity of the oven.
The advantages of this type of molding are:low mold cost, strain-free parts, and uniform

ACKUP PLATES SEALING HEATING CHANNELS

wall thickness.

IND
ANTICSMOLDING SURFACESREINEORC,ED

PLASTICSOLVENT MOLDING

MATERIAL.

SACKUP PLATES SLALOM HEATING CHANNELSREINFORCING

Thermoplastic materials are used in this process of forming.

Solvent molding is based on the fact thatwhen a mold is immersed in a solution andwithdrawn, or when it is filled with a liquid
plastic and then emptied, a layer of plastic film
adheres to the sides of the mold.

Some articles thus formed, like a bathing
cap or vial, are removed from the molds. Other

solvent moldings remain permanently on theform as, for example, a plastic coating on ametal tube.

COMPRESSED AIR

THERMOFORMING

Thermoforming of plastic sheet has developed
rapidly in recent years. Basically, this process

consists of heating thermoplastic sheet to aformable plastic state and then applying air
and/or mechanical assists to shape it to the

SHEET FORMING

contours of a mold.
Air pressure may range from almost zero toseveral hundred psi. Up to approximately 14
psi (atmospheric pressure), the pressure is ob-

tained by evacuating the space between the
sheet and the mold in order to utilize this atmospheric pressure. This range, known as
vacuum forming, will give satisfactory reproduction of the mold configuration in the majority of forming applications.

39

"When higher pressures are required, they are

obtained by sealing a chamber to the top sideof the sheet and building pressure within bycompressed air. This system is known as pressure forming.

Essentially, vacuum and pressure forming arevariations of the same basic technique, eventhough the difference in the formed parts may
be significant.
Variations of thermoforming include: straight
forming; drape forming; plug and ring forming;

slip forming; snap-back forming; reverse-draw
forming; air slip forming; plug-assist forming;plug-assist-air-slip forming; and machine die
forming.

TRANSFER MOLDINGCAVITY

Transfer molding is most generally used forthermosetting plastics.

This method is like compression molding inthat the plastic is cured into an infusible state
in a mold undcr heat and pressure. It differsfrom compression molding in that the plastic

KNOCIOU? PINS

is

TRANSFER MOLDING

heated to a point of plasticity before it

reaches the mold and is forced into a closed
mold by means of an hydraulically-operated
plunger,

Transfer molding was developed to facilitate

the molding of intricate products with small
deep holes or numerous metal inserts. The drymolding compound used in compression molding sometimes disturbs the position of the metal
inserts and the pins which form the holes. Theliquefied plastic material in transfer molding
flows around these metal parts without causing
them to shift position.

40 THE STORY OF THE PLASTICS INDUSTRYEducational

Facilities
Each year more schools, colleges and universities are adding instructions in plastics
to their curricula. As interest grows, newcourses are added, old courses realigned tobetter prepare students for the needs of theplastics industry.

MI==iMilMME
Trade

Publications

and Books
A wealth of information is contained in trade
and technical magazines and technical books
for and about the plastics industry. A listingof these publications is available.

Films About

Plastics

For these lists write to

THE SOCIETY OF THE
The Society of the Plastics Industry, Inc.,
has a list of motion picture films, film strips
and slides that are available from various organizations for showing. The list describes
the subject of each slide or film.

PLASTICS INDUSTRY, INC.
Public Relations Department
250 Park Avenue
New York, N. Y. 10017
Printed in U.S.A.