OAR Box 1878 

Prepped by Charmelle Mathews 

Document Number: 

59) 11-1-38 

Docket Number: 

A-90-19 

Printed 11/28/2008 11:47:27 AM Sheet 59 of 68 

P.1 
August 14, 1987 

P.2 

A-90-19 

II-I-38 

FINAL REPORT 

Preliminary Economic Analysis of 

the Proposed Revision to the Standard 

for 1,3-Butadiene: Phase II 

In Partial Fulfillment of Contract 

J-9-F-5-0058 

Submitted to: 

Mario DiStasio 

Office of Regulatory Analysis 

Occupational Safety and Health 

Administration 

U.S. Department of Labor 

Washington, D.C. 20210 

Submitted by: 

JACA Corp. 

Management Consultants and Engineers 

550 Plnetown Road 

Fort Washington, PA 19034 

> 
P.3 

as an Intermediate 1n nonpolymer uses such as the manufacture of the agricultural fungicides Captan and Captofol, the Industrial solvent sulfolane, 

and anthroquinone dyes [32]. A breakout of butadiene consumption by end 

use is shown 1n Table 2-7. 

Alone, tires and tire products account for roughly half of the butadiene consumed 1n the United States. Other end products manufactured from 

butadiene Include molded and extruded goods, belts, hoses, wire and cable 

coating, footwear, foam rubber, carpet backing, automotive goods, appliances, 

recreational equipment, adhesives, textiles, pipe, building materials, and 

toys [27]. Sketched out 1n Figure 2-2 1s the relationship between butadiene, Its derivatives, and the various end products manufactured from 

these derivatives. 

It 1s estimated that domestic consumption of butadiene 1n 1987 will 

again be in the neighborhood of three billion pounds. However, the demand 

for butadiene 1s expected to grow at an annual rate of only 0.8 percent 

over the next 4 years [3]. Demand for butadiene 1s derived mainly from the 

demand for elastomers in the tire and automotive Industries. Changes 1n 

these markets, such as smaller tires and Improved tire life have reduced 

the demand for butadiene-based elastomers and hence, butadiene. Some of 

the decrease 1n demand will be offset by growth 1n non-elastomer areas, 

such as acrylonltrlle-butadiene-styrene, but these applications are not 

expected to increase butadiene demand greatly. 

2.2 STYRENE-BUTADIENE RUBBER 

2.2.1 Description -

Styrene-butadiene elastomers are copolymers consisting of monomer 

units of 1,3-butadiene and styrene (C.6H5C2H3). A polymer with more than 50 

percent styrene 1s technically referred to as a styrene-butadiene 

elastomer, while one with less than 50 percent 1s called styrene-butadiene 

2-14 

JACA CORP. • MANAGEMENT CONSULTANTS & ENGINEERS 
P.4 

Table 2-7 

U.S. BUTADIENE CONSUMPTION: 1986 

(Millions of Pounds) 

Breakdown of 

Use Consumption End Use (%) 

Styrene-butadiene rubber (SBR) 

Polybutadiene (PBR) 

Polychloroprene (Neoprene) 

Nitrile Rubber (NBR) 

Adiponitrile/hexamethylenedlamine 

Styrene-butadiene copolymer latexes 

Acrylon1trile-butad1ene-styrene 

resins (ABS) 

Ethylene-Propylene-D1ene Monomer (EPDM) 

Other uses (Pesticides, Solvents, 

Propellants, etc.) 

1,207 

718 

228 

98 

359 

294 

163 

16 

50 

38.5 

22.9 

7.3 

3.1 

11.5 

9.4 

5.2 

0.50 

1.60 

Total 3,132 100.00 

Source: Developed by JACA from data in [3,20] 

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JACA CORP. • MANAGEMENT CONSULTANTS & ENGINEERS 
FIGURE 2-2 

iur*oiEHE DERIVATIVES AND n o USES IN END PRODUCTS 

P.5 

IKUB5DIATE5 FINAL POUHEIS/CHEHICAIS EH) USES 

•-> st urariHTlENE 

COPROOUCT 

CIU0E 

i 

I.MUIAOIEHE HONOHEI--) 

I 

»--) Sll-

- ) PXTtUTAOIEHE tUJIEI-

- ) A01P0NITRUE- - ) HElAltETHTLENEOIAHIHE (IDIOAl 

- > CHLOIOPREHE- -> HEOPREHE 

-) ACITLOHIIRIlE-IUIAOlEHE-SiriENE IESIHS (A8S)-

F 0 M 

tUC IACIIW 

tUIIEt COATED Ot SATURATED PtPEBS 

n c con 

HOH-IIOVEH FABRICS (HOSPITAL SHEETS. DISPOSABLE DIAPERS, 

AND BANDAGES) 

ADHESIVES 

MISCELLANEOUS APPIICATIOKS (UTD-MPFEO GOOOS, PICWKT 

BINDERS FOI PAWS , ADOIIIVES FOR fCHlANI CEHEHI, 

• AM ASIESTOS BINDING AGENTS IN IIAIE LININGS, 

GASIETS, AM LIMUUH) 

» - TIDES AMI TIKE PtODUCIS 

- ) ! HECHAHICAl GOOOS 

! HISCEUAHEODS APPLIUIIOHS (FOOIWEAI, ADHESIVES, 

• - SEALANTS, ElECIIICAL PIOOUCIS AHO OTHER USES) 

• - AUIOIIOtllE, TtUCt, AND JUS TIKES 

! HIGH-IMPACT IESIHS (IUIHLT POLTSTTtEKE) 

- I ! OIHEI USES (COKVETOR IELIS, GOLF BALLS. HOSES, SEALS, 

! GASIEIS. SHOE SOLES, HOIOt KOIMIS, FUIHIIUIE, TOTS, 

« - CASES FOI ELECTRICAL APMAHCES, AHO FLOOI TILE) 

*- HTLON 4.4 

i HTLON IESIHS (KTLON 4,9 AHO HTLOH 4,12) 

- ) ! HISCaiANEOUS APPLICATIONS (POLTURETHAHE COATINGS. 

! POLTAHIKE ADItESITES, INI IESIHS, AMI SPECIJHII 

•- SURFACE ACI IVE AGEHTS) 

IHOUSIIIAL IUBSEI GOOOS (HOSES AND IELIS, HU E ANO 

CAILE COATINGS, NON-WOVEN TEXTILES, AHO COATINGS FOI 

tOllS USED IH PIIHIIHG ANO FOOD PROCESSING) 

AUIOHOTIVE ANO IRAHSPORIAITOH PIOOUCTS (HOSES, IELIS, 

H U E AHO CAILE, COATED FABRICS. HIES, ADHESIVES, 

AHO GASIEIS) 

COHS1IUCIIOH PIODUCIS (LARGE SEALS FOR SANS AND 

RAIEIHAT LOCIS, PIPE AHO IANI LININGS, HEMIAHES FOt 

FLAI ROOFS, AOHESIVES, CEHEHIS. CAULIS, SEALANTS, 

PUITIES AHO PAIHIS) 

CONSUMER PIODUCIS (COATED FABRICS, PROIECIIYE CLOIHIHG, 

HEELS, AHO SOUS FOI FOOTUEAI, AHO IECIEAIIONAL 

EOUirHEHTI 

I - APPLIAIICES (IFFIIGEIAIOIS. DASHERS. FAHS, AHO VACUUH 

CLEANERS) 

BUSINESS HACHINES ANO IELEPHOHES 

COHSUNEI ELECIROHICS (IELEVISIONS AND IAOIOS) 

FURNITURE 

LUGGAGE 

IIOOIFIERS 

- ) ! PACfAGING 

BUILDING AND COHSIIUCIIOH HATFRIALS (PIPES AHO PIPE 

FIITIHGS, FAUCETS, SlfOHER HEADS, BATHIUiS, ANO 

CONDUITS) 

RFCREATIOH EOUIPHEHI 

IIAHSPOIIAIIOH PIODUCIS (AUIOHOIIIE IHIEIIOR AHO 

EIIEIIOR COHPUHEHIS) 

OIHEI USES 

X 

2-16 

JACA CORP • MANAGEMENT CONSULTANTS & ENGINEERS f 
1 

P.6 

EIHTUHE 

COPtOOUCT 

CRUDE 

I 

U-IUTAOIEHE IIOHONEI—> I 

I 

1 

I 

a 

- ) BUTADIENE ACtrlOHITRIlE UIEX-* -

I 

J 

i 

• - > NITRIIE RUBIEt-

-1,4-HEXAOIEXE- - ) EIHTLEHE-PROPTIEHE-OIEK HOHONER ELASIOHER (EPOH)-),' 

SIAFOtEHEt - 1 SUIFOLAHENITIILE LATEX ADHESIVE (NOH-WVW FABRIC tlNDEtS, 

FLOCIIHG ADHESIVES, PAPEI [NPREGHATIOH, LEAIKER, 

AID} TEXTILE IRUIKEHI, GAStET PAPEI. AND OIL FILTER 

BONDING) 

SOLUTION ITTt ADHESIVE (IOND SOFT VIHTl. BETAIS, CUS S 

PUSIICS , HOOD, tUBtEI. CaiW.OII.aOIH , LEATHER, 

AW VULCANHED RUBBER) 

miRILE/EPOXIDE ADHESIVE (BONO RETAIS AND HONTTCORI 

STRUCTURES) 

PHEHOL-FORHALOEHTDE/HIltaE ADHESIVE (AUTOHOIILE 

BRACE LIKINGS, NEIAl ALLOT BONDING FOI AIRCRAFT 

CONPtSIIE STRUCTURES, COPPER FOIL BONDING IN PIINIEI 

CIRCUIT IOACSS. AND IONDING NIHILE tUIIEI, PTC. 

LEATHER, ROM, AND PLASTICS) 

« -ROSES 

! SEALS AND GASIEIS 

! KUD U GOOOS 

i on Fiat EOUIPNENI 

- 1 ! SPONGE 

! BEltlNC 

,' FOOTWEAR 

! HIRE ANO CABLE 

» - NISCEllEANOOS 

< ~ AUIOROBILE PARIS HOH-IIRE (HOSES, HEATHER STRIPPING ANO 

,' SEALS, GROIOtEIS, AHO MODIFICATION OF PLASTICS AND 

! ELASTOMERS USED IN (HE lUKUFACIURE OF AUIOHOBILES) 

! HIES AHO TUBES 

! HIRE AND CABLE INSULAIION 

APPLIANCES 

! POLTHER RODIFICAIIOH 

! INOUSTIIAI HOSE (NliH-AUTOHOSIVE) 

! SINGLE-PIT ROOFING 

! OIL ADOIIIVES 

! IHERNOriASlIC ElASIOWRS 

•-- OIHER USES 

) LUIRICAHI PRODUCTION 

) EXIIACIIVE SOLVENT FOI AROMATICS A ACIO GAS PURIFICATION 

IETIAHTDIOPHIHALIC AOHTORIDE-*-

• - > CAPIAN-

) l-II — 

) IUTADIEHE-VIHTLPTIIDIHE LAIEX 

- ) LIOUID POLTIUIAOIEHE 

-> LIQUID POLTBUIAOIENE RESINS— 

'-- ALITD IESIHS 

- > ! UNSATURATED POLTESIEI IESIHS 

» - - PVC PLASIICHEIS ANO STABLUERS 

->»- - FOLIAGE FUNGICIDE 

••- SEED DRESSINGS 

-)• - INSECT IEPELLAHI 

'-- OELOUSING AGENI 

-)• - TIIE CORD ADHESIVE 

t ~ HIRE AND CABLE IHSULAIIOH 

) ROCIEI FUEL BIHDER 

l - AOOIIIVES IN THE RUBBER INDUSIRT 

, | HuctEAR REACTOR CORE COATINGS 

! DEEPHEll OIL CABLE COATINGS 

I - CAN COATINGS 

) LIOUID POUBUIAOIEHE-SITIEHE RESINS 

- ) LIQUID VIHTl POimHAOIEHE RESINS 

I - ADOIIIVES IN THE RUBIER INDUSIRT 

- ) l NUCLEAR (FACTOR CORE COAIINGS 

« - DEEPHEll Oil CAILE COAIINGS 

I-- ADOIIIVES IN IHE RUBIER INDUSIRT 

•>! NUCLEAR REACTOR CORE COMINGS 

» - - DEErwEU OIL CAILE COAIINGS 

s 

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JACA CORP. • MANAGEMENT CONSULTANTS & ENGINEERS 
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rubber (SBR). As the styrene content Increases, the polymer becomes 

Increasingly plastic, with a concomitant Increase 1n rigidity and loss of 

elongation properties. 

To simplify the discussion, both types of polymers will be referred 

to as SBR. SBR 1s marketed 1n a solid crumb form as either a random 

copolymer which 1s formed and then cured with heat (thermoset), or as a block 

copolymer 1n which fairly long sequences of the monomers are joined to form 

a thermoplastic elastomer [32]. Production of SBR crumb accounts for the 

single largest use of butadiene (38.5%). SBR 1s also produced 1n a liquid 

form known as latex. This 1s discussed 1n Section 2.5 

2.2.2 Manufacturing Process 

SBR crumb is manufactured using either an emulsion process or a solution process. In comparison to SBR produced by the emulsion process, SBR 

produced by the solution process generally has a narrower molecular weight 

distribution and a higher ds-butad1ene composition. Also, because of differences in molecular structure, solution SBR requires less accelerator to 

attain a given degree of hardness. This lower accelerator content results 

1n better product characteristics such as greater resilience and blowout 

resistance [27]. 

In the emulsion method of production, the process may be carried out 

at either a high temperature (around 60°C) or a low temperature (around 

5°C) in a monomer and water dispersion stabilized by a surfactant. A catalyst is used in generating free radicals to facilitate polymerization [32]. 

In the hot process/polymerization is allowed to continue until 60 to 70 

percent conversion Is achieved. In the cold process, the reaction 1s 

stopped at about 60 percent. In both the hot and cold processes, the 

unreacted butadiene and styrene are recovered by vacuum flashing and steam 

stripping, then recycled to the production process. Cold SBR 1s produced 

mainly for use 1n tire manufacture, and accounts for about 90 percent of 

the total domestic production of emulsion SBR. The cold process produces a 

product which is superior to the hot process because the cold product contains more higher-molecular weight polymers. Hot SBR, which is easier to 

> 

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JACA CORP. • MANAGEMENT CONSULTANTS & ENGINEERS 
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1 

i 

i 

i 

mill and extrude because of its low-molecular weight fraction, 1s used 

mostly for adhesive applications [27]. 

In the solution method of producing SBR, a monomer/solvent feed 1s 

polymerized into a solution called rubber cement. The polymerization 

1s carried out 1n the presence of catalysts of the Ziegler-Natta or 

Friedel-Crafts types. Production proceeds 1n a stepwise fashion on a semicontinuous basis, 365 days per year. The major feedstocks used in the process 

include butadiene, styrene, Isoprene, Isobutylene, ethylene, and propylene. 

Polymerization occurs through an 1on1c mechanism 1n a series of reactors. 

Reaction temperature 1s controlled through the use of refrigerants. 

Shortstops are used to terminate the reaction when the desired degree of 

conversion has been achieved. Following this, the rubber cement 1s pumped 

to storage tanks to await further processing. While the rubber 1s coagulated Into crumb, solvent and unreacted monomer are stripped with steam or 

hot water, then sent on to a recovery process. The crumb slurry 1s washed 

with water, screened, dewatered, then finished. 

2.2.3 Producers, Capacities and Output 

As shown 1n Table 2-8, SBR crumb 1s currently produced by six companies at six locations. All of the facilities are located in the Gulf 

Coast areas, of Texas and Louisiana, and of the six facilities, only the 

F1restonev plant employs the solution process. However, Goodyear is adding 

capacity to produce SBR by the solution process [9]. Total annual capacity 

for the industry now stands at 2.3 billion pounds. By far the largest producer is Goodyear, which accounts for 38 percent of Industry capacity. Not 

listed 1n the table 1s Shell Chemical's Bel pre, Ohio, facility for manufacturing thermoplastic styrene-butadiene block copolymers. This plant has not 

been Included since the properties of these copolymers differ from those of 

SBR. 

Industry capacity has declined somewhat 1n recent years. In 1984, 

Phillips Petroleum closed down Its 198-milllon-pound-a-year facility 1n 

Borger, Texas. In 1983, Firestone shut down its 419 million pound emulsion 

plant in Lake Charles, Louisiana. Also, in 1981, American Synthetic Rubber 

> 

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JACA CORP. • MANAGEMENT CONSULTANTS & ENGINEERS 
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Table 2-8 

PRODUCERS OF STYRENE-BUTADIENE RUBBER 

Company 

Copolymer Rubber 

and Chemical 

Corp. 

Firestone Tire 

and Rubber Co. 

General Tire and 

Rubber Co. 

B.F. Goodrich Co. 

Goodyear Tire 

and Rubber Co. 

Synpol Inc. 

Location 

Baton Rouge, 

Lake Charles 

Odessa, TX 

Port Neches, 

Houston, TX 

Port Neches, 

LA 

, LA 

TX 

TX 

Process 

Type 

Emulsion 

Solution 

Emulsion 

Emulsion 

Emulsion 

Emulsion 

TOTAL 

Annual Capacity 

(Millions of 

Pounds) 

276 

265 

298 

329 

871 

368 

2,307 

Percent 

Industry 

Capacity 

12.0 

11.5 

8.5 

14.2 

37.8 

16.0 

100.0 

Sources: [19,27] 

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JACA CORP. • MANAGEMENT CONSULTANTS & ENGINEERS 
P.10 

Mothballed Its 220-m11l1on-pound unit in Louisville, Kentucky. Altogether, 

Industry capacity has declined by about 30 percent since 1980 [19]. Table 

2-9 shows production of SBR 1n the United States over the years 1968-1985. 

The peak during this period was reached 1n 1973, when 2,963 million pounds 

of SBR were produced. The low point was 1n 1983, when output was only 

1,489 million pounds. Production of SBR recovered, and 1n 1985 was 1,538 

million pounds. However, this figure still represents a decline of 43 

percent from 1979 production levels. Changes In the automobile and tire 

industries have drastically reduced demand for SBR over the last 10 years. 

Production of SBR is expected to be flat over the next 5 years. 

Foreign trade 1n SBR 1s shown 1n Table 2-10. In 1985, the U.S. 

imported 209 million pounds of SBR (13% of demand) and exported 134 million 

pounds (almost 9% of production). 

Currently, producers could manufacture considerably more SBR than 

their official listed capacities suggest. Some estimates place overcapacity of domestic producers at close to 30 percent. Because of this 

overcapacity, price cutting has become a major problem for domestic producers. The economic recovery has encouraged a number of SBR manufacturers 

to continue production; however, depressed prices could discourage reinvestment in plant and equipment, and eventually lead to more closures [25]. 

i 

2.2.4 Uses-and Consumption Trends 

In all of the applications of SBR, the most attrative feature 1s its 

low cost. SBR is still the lowest priced general-purpose rubber on the 

market. Other attractive features include good resistance to abrasion, 

cracking, and wear. In comparison with natural rubber and many synthetic 

rubbers, SBR has superior heat resistance and allows smoother extrusions. 

In addition, SBR adheres well to many surfaces because of Its stickiness, 

is easily moldable, has relatively high tensile strength compared with 

other inexpensive elastomers, and has good elongation properties [32,40]. 

Table 2-11 shows the current pattern of end uses for SBR. The 

largest use — 79 percent — is 1n the production of tires and tire products. Mechanical rubber goods account for another 9 percent, and the 

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JACA CORP. • MANAGEMENT CONSULTANTS & ENGINEERS 
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Table 2-9 

U.S. PRODUCTION AND CONSUMPTION OF 

SBR: 1968-85 

(Figures in Millions of Pounds) 

Year 

1985 

1984 

1983 

1982 

1981 

1980 

1979 

1978 

1977 

1976 

1975 

1974 

1973 

1972 

1971 

1970 

1969 

1968 

Estimated. 

Production 

1,538 

1,885 

1,489 

1,738 

2,085 

2,247 

2,692 

2,821 

2,819 

2,679 

2,398 

2,677 

2,963 

2,953 

2,848 

2,650 

2,776 

2,776 

Sources: [45 to 56] 

Consumption 

1,606 

1,475 

1,452 

1,687 

1,982 

2,009 

2,542 

2,768 

2,750a 

2,589a 

2,372a 

2,812 

3,027 

2,949 

2,782 

2,451 

2,614 

2,567 

1-11 

JACA CORP. • MANAGEMENT CONSULTANTS & ENGINEERS 
1 

1 

1 

1 

1 

1 

1 

1 

1 

f 

i 

1 

1 

fl 

fl 

1 

fl 

fl 

J 

„ * * 

Year 

1985 

1984 

1983 

1982 

1981 

1980 

1979 

1978 

1977 

1976 

Sources: 

IMPORTS AND 

Imports 

209 

103 

92 

83 

79 

56 

117 

92 

30 

' 45 

[45 to 52] 

Table 2- 10 

EXPORTS OF STYRENE-BUTADIENE RUBBER: 

(Millions of Pounds) 

Imports as a 

Percent of 

Production 

13.0 

7.0 

6.3 

5.0 

4.0 

2.8 

4.6 

3.3 

1.1 

1.7 

> 

2-23 

Exports 

134 

171 

139 

135 

181 

294 

216 

145 

127 

142 

1976-85 

Exports as a 

Percent of 

Production 

8.7 

9.1 

9.3 

7.8 

8.7 

13.1 

8.0 

5.1 

4.5 

5.3 

. 

JACA CORP. • MANAGEMENT CONSULTANTS & ENGINEERS 

P.12 
P.13 

Table 2-11 

END USES FOR SBR 

Products Breakdown by End Use (%) 

Tires and tire products 79.1 

Mechanical rubber goods 9.9 

Footwear, adhesives, sealants, 11.0 

electrical products, and other uses 

TOTAL 100.0 

Sources: [19,27] 

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JACA CORP. • MANAGEMENT CONSULTANTS & ENGINEERS 
P.14 

remainder by footwear, adhesives, sealants, electrical productions, and 

miscellaneous uses. 

Table 2-9 presents annual domestic consumption of dry SBR for the 

period 1968-85. In 1985, a total of 1,606 million pounds were consumed. 

This represented a 1.6 percent Increase over the preceding year's level of 

1,452 million pounds. The upturn, however, does not appear to signal a 

long-term recovery 1n demand. Some Industry experts have predicted that 

the domestic demand for SBR will decline by 0.3 percent a year until 1991 

[9]. This expectation 1s based in large measure on a projected decline in 

the demand for automobile tires. The U.S. automobile Industry's strong 

1985 performance boosted demand for SBR temporarily, but 1t is unlikely 

that the Industry will continue at that level. 

As in the past, the demand for SBR will continue to be shaped largely 

by developments 1n the automobile and tire industries. The market for SBR 

has been permanently reduced by the trend toward smaller cars equipped with 

longer wearing radial tires (which consume less SBR by weight than bias 

tires). Other factors having a negative influence on demand are the 

growing popularity of imported cars which come equipped with foreign-made 

tires, and the significant upturn in sales of imported replacement tires, 

whose low cost has adversely affected sales of retreaded tires. 

Problems have also begun to develop 1n non-tire markets. In the 

manufacture of automobile and electrical parts, for example, SBR has begun 

to lose sales to thermoplastic blends and ethylene-propylene elastomers 

[19]. 

2.3 POLYBUTADIENE 

2.3.1 Description 

About 23 percent of the total consumption of butadiene goes into the 

production of polybutadiene. Polybutadiene is a homopolymer produced by 

polymerizing butadiene with itself. Although polybutadiene, Itself, is a 

commercially important end product, the bulk of this polymer is blended 

with natural rubber or copolymers such as SBR or acrylonitrile-butadiene 

2-25 

JACA CORP. • MANAGEMENT CONSULTANTS & ENGINEERS 
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styrene. When included in a blend, polybutadiene adds rubbery, flexible 

properties, provides better mold flow, and Improves low temperature qualities. By combining polybutadiene with natural rubber, a product 1s obtained 

which has high abrasion resistance, a lower tendency to flex cracking, 

superior aging resistance, good resistance to heat buildup, and better 

resilience and tensile strength [27]. 

Four stereostructural polybutadienes are possible: ds-1,4; trans-1,4; 

vinyl 1sotact1c-l,2; and vinyl synd1otact1c-l,2. The d s Isomer 1s preferred 

because of its superior processing characteristics and ability to impart 

greater flexibility in end products. Generally, however, Isomeric mixtures 

are produced [27]. 

2.3.2 Manufacturing Process 

The commercial production of polybutadiene 1n the United States dates 

back to the 1950s, when a coordination catalyst was developed which permitted 

the use of an ionic process enabling better control over polymerization. 

Polybutadiene may be produced by either solution or emulsion polymerization. 

For the most part, however, production 1s by means of the solution process. 

In solution polymerization, the relative amounts of the various polybutadiene isomers in the finished product are controlled by the choice of 

catalysts. Among the more commonly-used catalyst systems are the cobalt 

complex, iodine-Ziegler, nickel complex, and n-butyl-lithium. 

Diagrammed in Figure 2-3 is a typical process for the manufacture of 

cis-l,4-polybutadiene. The process consists of four major stages: (1) 

purification of the"butadiene and solvent; (2) reaction and concentration; 

(3) blending and solvent removal; and (4) drying and packaging. In the 

first stage, the butadiene 1s pumped to a purification unit where 1t 1s 

distilled and dried to remove Inhibitor and moisture. The same procedure 

1s used to remove unwanted water from the solvent. In the second stage, 

the catalyst, butadiene and solvent are passed through a series of reactors 

where polymerization takes place. The polymer stream emerging from the 

last reactor is flash evaporated to remove unreacted butadiene and solvent. 

y 

2-26 

JACA CORP. • MANAGEMENT CONSULTANTS & ENGINEERS 

I 

I 
P.16 

BUTADIENE 

CAUSTIC 

HASH 

r\ 

NAOHHATER 

A 

T_ 

FRESH 

SOLVENT X 

, SOLVENT 

COOLAMT^ 

FRACTIONATOR 

BUTADIENE & SOLVENT 

FRAaiONATOR 

CATALYST 

DECANTOR f s =^25 

I \ , /| 

WASTE 

ORGANICS 

WATER 

SOLVENT 

REMOVAL 

coo: ,LAC!3 

SHORTSTOP CONCENTRATOR 

( I 7 

ANTIOXIDANT 

BLEND 

TANK 

SCREEN 

FILTER POLYBUTADIENE 

PRODUCT 

DRYER "FTBALER | ITT 

Source: [39] 

Figure 2-3 

PRODUCTION OF CIS-POLYBUTADIENE 

? 1-21 
P.17 

I 

I 

The unreacted butadiene and solvent are recycled back to the reactors. In p 

the third stage, the thickened polymer stream is conveyed to blending tanks 

where several batches of polymer are blended to obtain a uniform mixture. fl 

Following this, steam stripping is employed to recover toluene for reuse. 

The stripping process leaves behind a polymeric crumb slurry. In the 

fourth and final stage, the slurry 1s passed over dewatering screens, dried 

by extrusion, baled, then wrapped 1n polyethylene film [27], 

2.3.3 Producers, Capacities and Output 

Currently, solution-polymerization polybutadiene is produced by four 

companies at four facilities. The combined annual production capacity of 

these units is 838 million pounds. Table 2-12 lists the producers, the 

plant locations, and the plant capacities. The largest producer 1s 

Goodyear, whose Beaumont, Texas facility accounts for 36 percent of the 

total Industry capacity. 

The only producer of emulsion-polymerization polybutadiene is Synpol, 

which manufacturers this product along with SBR at a facility in Port 

Neches, Texas [19]. As alluded to earlier, the production of solution 

polymerized polybutadiene far exceeds the production of emulsion-polymerized product. In 1979 (the most recent year for which data are available), 

only 43 million pounds of emulsion-polymerized polybutadiene were manufactured compared to 875 million pounds of solution polymerized product [59]. 

In 1984, there was a closure of a 141-million-pound-a-year facility 

jointly owned by Phillips, Armstrong Rubber, and General Tire. Other than 

this, industry capacity has changed very little in recent years. Capacity 

utilization is estimated to be above 78 percent at present [29]. 

Domestic production of polybutadiene for the period 1976-86 is shown 

in Table 2-13. Traditionally, the production of polybutadiene has followed 

the general business cycle. However, despite a relatively strong economy 

1n 1986, production of polybutadiene slipped 1.5 percent to 716 million 

pounds. Production of polybutadiene, like that of other synthetic rubbers, 

has been hurt by imported cars and improved tire life. Changes in the 

market for synthetic rubber will limit polybutadiene production to slow 

growth over the next 5 years. 

y 

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JACA CORP. • MANAGEMENT CONSULTANTS & ENGINEERS 

f 
P.18 

1 

I 

J 

I 

I 

fl 

fl 

fl 

fl 

fl 

A 

Table 2-12 

PRODUCERS OF POLYBUTADIENE RUBBER 

Company 

American Synthetic 

Rubber Corp. 

Firestone Tire 

and Rubber Co. 

General Tire and 

Rubber Co. 

Polysar Group 

Synpol Inc. 

Location 

Louisville, ICY 

Orange, TX 

Beaumont, TX 

Orange, TX 

Port Neches, TX 

Process 

Type 

Solution 

Solution 

Solution 

Solution 

Emulsion 

TOTAL 

Annual Capacity 

(Millions of Pounds) 

139 

243 

302 

154 

a 

838 

aNot available. 

Source: [16] 

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JACA CORP. • MANAGEMENT CONSULTANTS & ENGINEERS 
P.19 

Table 2-13 

U.S. PRODUCTION AND CONSUMPTION 

OF POLYBUTADIENE, 1976-86a 

(Figures 1n Millions of Pounds) 

Year 

1986 

1985 

1984 

1983 

1982 

1981 

1980 

1979 

1978 

1977 

1976 

Production 

716 

727 

792 

734 

635 

754 

686 

875 

833 

796 

776 

Consumption 

b 

835 

904 

795 

585 

763 

683 

910 

883 

887 

793 

aIndudes latex. 

bNot available. 

Sources: [4, 45 to 56] 

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JACA CORP. • MANAGEMENT CONSULTANTS & ENGINEERS 
P.20 

In 1985, the United States Imported 147 million pounds of polybutadiene. Foreign polybutadiene represented 18 percent of domestic demand. 

As shown 1n Table 2-14, Imports of polybutadiene have fluctuated year to 

year depending on general economic conditions. Currently, Imports are at 

their highest level for any of the years shown. Exports of polybutadiene 

have been subject to wide fluctuations as well. In 1985, U.S. producers 

exported 53 million pounds of polybutadiene. 

2.3.4 Uses and Consumption Trends 

The current pattern of end uses for polybutadiene is shown in Table 

2-15. Of total domestic consumption, 80 percent is used in the manufacture 

of automobile, truck, and bus tires. Combined with natural rubber and SBR, 

polybutadiene is used in the production of tire treads to increase 

resistance to abrasion and cracking. As much as 30 percent of the rubber 

used in carcass compounds and sidewall stocks may be polybutadiene. It is 

used in this application to improve resistance to heat degradation and 

blowouts [32]. 

Non-tire uses capitalize upon polybutadiene's resistance to abrasion 

and flex cracking, resilience, and low temperature flexibility. Among 

these miscellaneous uses are conveyor belts, golf balls, hoses, seals, 

gaskets, shoe soles, motor mounts, furniture, toys, cases for electrical 

appliances, and floor tile [27,31,42]. 

Domestic consumption of polybutadiene 1s shown in Table 2-13. The 

1985 level of 835 million pounds represents an 8 percent decline from the 

previous year. The demand for polybutadiene has Increased since 1982 by 

nearly 20 percent; however, future growth for polybutadiene will be slow. 

Industry experts predict that the use of polybutadiene 1n tires will eventually give way to new solution polymers. The Rubber Manufacturers Association predicts an annual growth rate of 1.4 percent 1n polybutadiene 

demand through 1991 [9]. 

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JACA CORP. • MANAGEMENT CONSULTANTS & ENGINEERS 
Table 2-14 

IMPORTS AND EXPORTS OF POLYBUTADIENE: 1975-85 

(Millions of Pounds) 

P.21 

I 

f 

t 

Year Imports 

Imports as a 

Percent of 

Consumption Exports 

Exports as a 

Percent of 

Production 

1985 

1984 

1983 

1982 

1981 

1980 

1979 

1978 

1977 

1976 

1975 

147 

143 

107 

66 

66 

69 

97 

98 

124 

59 

44 

17.6 

15.8 

13.5 

11.3 

8.6 

10.1 

10.7 

11.0 

14.0 

7.4 

6.3 

53 

54 

36 

32 

62 

77 

60 

34 

27 

47 

27 

7.3 

6.8 

4.9 

5.0 

8.2 

11.2 

6.9 

4.1 

3.4 

6.1 

4.2 

Sources: [45 to 56] 

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Table 2-15 

END USES FOR POLYBUTADIENE 

Products Breakdown by End Use (%) 

Automobile, truck and bus tires 80 

High-impact resins (mainly polystyrene) 16 

Other uses 4 

TOTAL 100 

Source: Developed by JACA from data contained 1n [16] 

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JACA CORP. • MANAGEMENT CONSULTANTS & ENGINEERS