VESTAKEEP®
PEEK—Polyether Ether Ketone Compounds

Evonik Industries is the creative industrial group from Germany focused on chemicals, energy and real estate.
Evonik is a global leader in specialty chemicals. Together with the Acrylic Monomers and Acrylic Polymers
Business Lines the High Performance Polymers Business Line is a part of the Performance Polymers Business Unit.
High Performance Polymers is specialized in manufacturing customized products and systems. We have been
producing high-performance plastics for over 40 years. The extension into the field of HT polymers represents
a logical expansion of our product portfolio.

Directory
1 Introduction ....................................................................................... 5
Manufacture ...................................................................................... 5

Applications ....................................................................................... 6

Delivery ............................................................................................. 8

Technical service ................................................................................ 8

2 Overview of VESTAKEEP compounds ................................................ 9®

3 Physical, thermal, tribological and mechanical properties,
and fire behavior of VESTAKEEP® compounds ...................................

11

4 Processing ...................................................................................... 18
Injection molding ............................................................................

18

Extrusion ........................................................................................ 23

5 Physiological and toxicological evaluation of
VESTAKEEP® compounds ................................................................ 28

6 Information about environmental compatibility
and safety ....................................................................................... 30

Regional contacts ............................................................................ 31

VESTAKEEP®:High Performance Polymers expanded

High-Performance Polymers has further expanded its technological lead in the high-performance polymers sector
with VESTAKEEP® polyether ether ketone (PEEK1) compounds. VESTAKEEP® compounds are particularly suitable
for applications in which extremely high mechanical, thermal, and chemical requirements must be met.

Evonik markets its VESTAKEEP® compounds worldwide. A proven quality
management system ensures a high levelof quality for the products introduced on
the market, from development throughproduction, and to quality assurance.
Our system is ISO 9001:2000 and
ISO/TS 16949:2002 certified and iscontinually optimized. A large numberof customers have tested this quality
system over the years and have attested
to its excellence.

VESTAKEEP® compounds are particularly
characterized by the following material
properties:

For development and production, we
have also introduced an environment
management system complying with
ISO 14001:2005, and this is regularly
certified.

. good strength. very high heat resistance. high rigidity. low water absorption and therefore
high dimensional stability. high hardness. excellent sliding friction behavior,minimal abrasion. good electrical characteristics

This brochure provides an overview ofthe properties and applications of
VESTAKEEP® molding compounds, aswell as processing information.
VESTAKEEP® powders are covered in a
separate brochure.

. excellent chemical resistance. excellent hydrolytic stability. good processability. low tendency to form stress cracks

1

PEEK is the official abbreviation for polyether ether
ketone according to ISO 1043. In this brochure it
will be used only in this context.

4

1 Introduction
Manufacture
VESTAKEEP® is polycondensed from thebuilding blocks hydrochinone and 4,4´difluorobenzophenone in a multistage
process.

The base grades have a melt viscosity of
100–3,000 Pas, measured at 400 °C, anda low shear of 1 sec-1, which is right for
injection molding and extrusion applications.
To meet the requirements of different
applications, manufacturers can adjust theproperties of pure PEEK selectively byadding various additives:. Processing aids facilitate demolding.
. Fillers and reinforcing materials increase
rigidity and dimensional stability upon
exposure to heat. Chopped carbon
fibers are most effective for this. Minerals and glass microbeads also counteract the tendency to warp.

5

Table 1: Performance profile of polyether ether ketones for particular applications

High temperature resistance

VESTAKEEP® compounds can be used fora wide range of applications, such as inelectrical, electronic, and communications
engineering and in the automotive industry. Table 1 lists the properties that are
particularly relevant to various applications.
As mentioned before, all high-performance plastics from the High Performance
Polymers Business Line meet the highest
quality standards.

Automotive

Aerospace andrail cars

Machinery andapparatus
construction

Electrical and cable

Electronics andsemiconductors

Medical technology

Food processing
industry***"Free of toxic fumes" does not apply to compounds containing PTFE.
See Section 6, "Information about environmental compatibility and safety"

6

Chemical resistance

Applications

7

Sterilizability

Processability

Dimensional stability

Ion extraction

DegassingElectrical properties

Toxic fumes ***Fire behavior

Wear resistancePhysical stability

Hydrolysis resistanceDelivery of VESTAKEEP®
compounds

Technical service CAE support

As granules: in boxes with a total content
of 25 kg, divided into two polyethylene
liners each holding 12.5 kg. Twenty-fiveboxes with a total weight of 625 kg fit on
one pallet.
As a powder: in 10 kg boxes, each box
having one polyethylene liner. Twentyfive boxes with a total weight of 250 kg
fit on one pallet.
As a fine powder: in 15 kg boxes, eachbox having one polyethylene liner.
Twenty-five boxes with a total weight of
375 kg fit on one pallet.
We will also deliver in bulk packaging
upon request.
Under normal storage conditions, storage
time is practically unlimited provided thatthe packaging has not been damaged.
Avoid storing at temperatures above 45 °C.

Our technical service includes comprehensive application engineering advice
with the aim of jointly working out technically demanding system solutions withour customers. This also includes support
from various CAE methods in the development of molds and molded parts.

Like other partially crystalline polyaryl
ether ketones, unmodified VESTAKEEP®
appears amber-colored in the melt andgrayish in its solid crystalline state (natural colors). VESTAKEEP® is translucent in
its solid, amorphous state and has a characteristic amber color. We deliver most compounds in their natural colors. Others havea certain color inherent to them becauseof the additives they contain. They areavailable in four viscosity series, namely
VESTAKEEP® 1000, 2000, 3000 and
4000, where 1000 indicates the lowest
viscosity and 4000 indicates the highest.

We perform processing simulations of theinjection-molding process from the fillingphase to the holding-pressure phase, including the calculation of shrinkage anddistortion, with modern software. This
enables us to provide the following data
as early as during the product development phase. Processing process: e.g., fillability ofthe mold, resulting process parameterslike pressure and temperature distributions, cooling system, influence ofvarious processing parameters. Component properties: e.g., location of
weld lines, air bubbles, shrinkage anddistortion, fiber orientation. Manufacturing costs: required machinesize, cycle time, complexity of molded
part/mold

As a rule, we require that our customers
provide us with an IGES file describing
the geometry of the article and, depending on the problem definition, information regarding constraints, such as moldand process requirements. We will enter
relevant material properties such as shear
viscosity, thermal conductivity and PVT
behavior into the calculation.
The results from the simulation calculation
support further design and optimizationof the molded part and its associated injection mold. This frequently results in a
reduction of cost-intensive modifications
and in the number of iterative loops on
the mold and molded part.
Our qualified teams in Application Technology and Market Development discuss
the problem definition and results with thecustomer and jointly work out solutions.

Filling study example of asample part8

2 Overview of
VESTAKEEP® Compounds
Commercial products

Powders

The PEEK compounds from High Performance Polymers include a variety of different products that have been matched to
the requirements of processors and end
consumers. Table 2 provides an overview
of the characteristics of the most important products and their typical applications. More detailed information aboutmost of these compounds can be found in
Tables 3 and 4. For further information
about the other compounds, please contact the persons indicated.

In addition we offer VESTAKEEP® as
powders. They can be used in a wide
range of applications, for example, in thefood, electrical, electronics, and information technology sectors and in the automotive industry. The powders are processed by a number of different means:press sintering, electrostatic powder
spraying, flame spraying, fluidized-bed
powder sintering, sprinkling, or as a suspension, both in aqueous and in solventcontaining systems.
Please take note of the details in our
brochure “VESTAKEEP®—Polyether
Ether Ketone Powders “. Our employees
will be happy to provide further information and support.

Campus®
Other properties of VESTAKEEP® compounds and material information on theother products of the High Performance
Polymers Business Line are contained in
the plastics data base Campus ®2, which is
updated regularly. You'll find Campus on
the Web at www.evonik.com/hp

Development products
Development products are usually designed for a specific application. When we
introduce a product onto the market, thefindings and feedback we receive allow
us to optimize it further. Consequently, achange in the formulation or manufacturing process may lead to some slightchanges in the product's properties. We
immediately notify our customers of any
changes to the material's composition andhow these may influence the quality or
specifications of the product itself. If
you're looking for a product with a special requirements profile, please contact
the person indicated.

2

Campus® is the registered trademarkof CWF GmbH/Frankfurt (Main)

9Overview of VESTAKEEP® grades

5000 P

3000 P

4000 P

5000 G

2000 P

1000 P

L 4000 G

3300 G

2000 G

1000 G

4000 G blackcompounded*2000 G blackcompounded

3000 GF30*

ground4000 FP

compounded

ground1000 CF30

3000 FC30*

2000 FP

3000 CF30*

2000 UFP20

4000 GF30

4000 FC30

4000 CF30

2000 UFP10

compounded

2000 GF30

2000 FC30

2000 CF30

G = Granules
P = Powder
FP = Fine powder
UFP = Ultrafine powder
GF30 = glass fiber-reinforced 30%
FC30 = PTFE/graphite/carbon fiber (10:10:10)
CF30 = carbon fiber 30%* on request10

3 Properties of
VESTAKEEP® Compounds
Table 2: Overview of VESTAKEEP® compounds and their properties
VESTAKEEP®

Properties

Product line and applicatons

Processing

1000 G

unreinforced, low-viscosity, easy-flowing

low to medium-viscosity base grades for

IM, E (film)

2000 G

unreinforced, medium-viscosity, lubricatedproducts such as gear parts, parts used in

IM, E (film)

medical technology, and films, sheets, andIM, E (film)

2000 G black

semi-finished products
3300 G

unreinforced, medium-viscosity, lubricatedspecialty grade for the cable industry

E

4000 G black

unreinforced, high-viscosity

high-viscosity base grades for products such

E, (IM)

unreinforced, high-viscosity, lubricatedas gear parts, parts used in medical techno-

E, (IM)

L 4000 G

logy, and films, sheets, and semi-finished

5000 G

products
30% carbon fibers

low to medium-viscosity, carbon fiber or glass

IM

2000 CF 30

30% carbon fibers

fiber-reinforced compounds with increased

IM

2000 GF 30

30% chopped glass fibers

rigidity used for machinery, apparatuses andIM1000 CF 30

aircraft and in the electrical industry
3000 CF 30*
3000 GF 30*

30% carbon fibers

medium-viscosity, carbon fiber or glass fiber-(E), IM

30% chopped glass fibers

reinforced molding compounds with increased(E), IMor high rigidity, partially low warpage, e.g.
for housing parts
4000 CF 30
4000 GF 30

30% carbon fibers

high-viscosity, carbon fiber or glass fiber-(E), IM

30% chopped glass fibers

reinforced molding compounds with increased(E), IMor high rigidity, partially low warpage, e.g.
for housing parts
10% graphite

special grades for applications such as bearing

IM

3000 FC 30*

10% carbon fibers

arrangements and gear parts with self-lubri-

E, IM

4000 FC 30

10% PTFE

cating characteristic for use in the electrical

E, IM

2000 FC 30

engineering, automotive, machinery andapparatus construction industries
IM = Injection molding, E = extrusion* on request

11

Flow behavior
The following illustrations serve as guidefor selecting a grade in terms of the flowability of VESTAKEEP® compounds. Theyshow how injection pressure affects theflow length of unreinforced and reinforced
compounds.

The values were obtained at a mold temperature of 180°C and at a processing
temperature ranging from 360 to 400°C.
The results are based on a flow spiral of
6 by 2 mm.

Unreinforced VESTAKEEP® grades
800
700
600
500

Flow length [mm]

400
300

...

200
100
0
50

100

VESTAKEEP® 1000 G
VESTAKEEP® 2000 G
VESTAKEEP® 4000 G

150
Injection pressure [MPa]

VESTAKEEP® 2000 and 4000 compounds
400
350
300
250

...
...

Flow length [mm]

200
150
100
50
0
50

100

VESTAKEEP® 2000 FC30
VESTAKEEP® 2000 GF30
VESTAKEEP® 2000 CF30
VESTAKEEP® 4000 FC30
VESTAKEEP® 4000 GF30
VESTAKEEP® 4000 CF30

150
Injection pressure [MPa]Tribological properties
Tribology deals with friction, lubrication,
and wear to bodies that come into contact
with each other. The following tableshows the initial results of a tribologicaltest with a slide in form of a pin made of
VESTAKEEP® and a rotating disk made of
100Cr6 steel.

12

The velocity was set at 0.5 m/s, and a
total distance of 2,000 m was measured.
Additional tests are being conducted withlonger total distances. Please ask the indicated contact persons about the current
status of these tests.

Tribological properties
VESTAKEEP®

Temperature, load

2000G

4000G

2000FC30

4000FC30

23 °C, 1 N
23 °C, 20 N
200 °C, 1 N
200 °C, 20 N

0.4
0.35
-

0.4
0.41
-

0.33
0.23
0.26
0.3

0.31
0.25
0.32
0.32

23 °C, 1 N
23 °C, 20 N
200 °C, 1 N
200 °C, 20 N

9.1
16.68
-

9.14
10.48
-

6.87
0.26
12.6
6.9

3.31
0.52
20
5.76

Coefficient of sliding friction

Wear [10 -6 mm3/Nm]

Weld line strength
For the purpose of determining weld line
strength, tensile test bars 150 x 10 x
4 mm3 in size were made on an experimental mold. If the runner inserts are
replaced, the mold can produce test bars
with and without a weld line. The moldsurface temperature for all tensile bars
was set to 180 °C.

Testing was done under standard conditions according to ISO 527. The results
are summarized in the table below. It is
obvious for unfilled molding compounds
that the weld line leads to practically no
decline in the stress at yield, while forfilled molding compounds tensile strength
declines by 50 to 70%.

Weld line strength
VESTAKEEP®

ISO 527-1/-2

Stress at yield [MPa]without weld linewith weld line

2000G

50 mm/min

100

99

4000G

50 mm/min

96

95

Tensile strength
2000CF30

5 mm/min

235

100

4000CF30

5 mm/min236

111

2000GF30

5 mm/min

161

79

4000GF30

5 mm/min

152

82

2000FC30

5 mm/min150

434000FC30

5 mm/min146

41

Weld line strength of various VESTAKEEP® grades
250

4000 CF30

200

4000 GF30
4000 FC30

150
4000 CF30

...
...

100

Stress [MPa]4000 GF30
50
4000 FC30
0
0.0

0.5

1.0

1.5

2.0

VESTAKEEP® 4000 CF30 without weld line
VESTAKEEP® 4000 CF30 with weld line
VESTAKEEP® 4000 GF30 without weld line
VESTAKEEP® 4000 GF30 with weld line
VESTAKEEP® 4000 FC30 without weld line
VESTAKEEP® 4000 FC30 with weld line

2.5
Strain [%]13

Table 3: Properties of VESTAKEEP® compounds
Properties

Standard

Unit

VESTAKEEP 2000 G

Physical and thermal properties and fire behavior
Density
23 °C

ISO 1183g/cm 31.30°C

approx. 340

Melting range

DSC, 2nd heating

Melt volume-flow rate (MVR)

380 °C/5 kg
400 °C/10 kg

Temperature of deflection under loadMethod A
Method B

ISO 1133
ISO 1133

cm /10 min
cm 3/10 min

70
-

°C
°C

155
205

°C
°C

335
310

10-4 K-1

0.6

%

38

ISO 75-1/2
1.8 MPa
0.45 MPa
ISO 306

Vicat softening temperature
Method A
Method B

10 N
50 N
ISO 11359

Linear thermal expansion
23 °C–55 °C
longitudinal
Oxygen index
Flammability acc. UL94

Glow wire test

GWIT
GWFI

3.2 mm

ISO 4589

0.8 mm
1.6 mmIEC 60695
IEC 60695

2 mm
2 mm

IEC 60695-2-12/13
IEC 60695-2-12/13

V-0
°C

875
960

%
%

0.7
1.2

%

0.5

MPa
%
%

100
5
30

ISO 294-4

Mold shrinkage
in flow direction
in transverse direction
Water absorption, saturation
Mechanical properties
Tensile test
Stress at yield
Strain at yield
Strain at breakTensile test
Tensile strength
Strain at break

23 °C

50 mm/min

5 mm/minISO 62

ISO 527-1/-2

ISO 527-1/-2
MPa%
ISO 527-1/-2

Tensile modulus

MPa

3700
2

CHARPY impact strength

23 °C-30 °CISO 179/1eU

kJ/m
kJ/m2

N
N

CHARPY notched impact strength

23 °C-30 °CISO 179/1eA

kJ/m2
kJ/m2

6C
6C

IEC 60112

-

200
175

K20/P50
K20/K20

IEC 60243-1

kV/mm
kV/mm

25
21

Relative permittivity

50 Hz
1 kHz
1 MHz

IEC 60250

-

2.8
2.9
2.8

Dissipation factor

50 Hz
1 kHz
1 MHz

IEC 60250

-

0.003
0.005

IEC 60093
IEC 60093
IEC 60093
IEC 60093

Ohm
Ohm*cm
Ohm
Ohm

1014
1015
1014
1015

Electrical properties
Comparative tracking index
Test solution A
Electric strength

Volume resistance
Volume resistivity
Surface resistanceSpec. surface resistance

14

3

CTI
100 drops value

VESTAKEEP 3300 G

VESTAKEEP 4000 G

VESTAKEEP 2000 GF30

VESTAKEEP 4000 GF30

1.30

1.30

1.50

1.50

approx. 340

approx. 340

approx. 340

approx. 340

20
-

11
-

17
-

2
-

155
205

155
205

323
338

312
335

335
305

335
305

340
335

340
335

0.6

0.6

0.3

0.3

38

38

45

45

V-1
V-0

V-1
V-0

V-1
V-0

V-1
V-0

850
960

850
960

875
960

875
960

0.7
1.2

1.1
1.8

0.4
0.9

0.4
0.7

0.5

0.5

0.4

0.4

98
5
25

96
5
30

165
2

165
2

3600

3500

11000

11000

N
N

N
N

55 C
65 C

70 C
75 C

6C
6C

7C
6C

9C
8C

10 C
9C

200
175

200
175

200
175

200
175

25
21

25
21

25
23

25
23

2.8
2.9
2.8

2.8
2.9
2.8

3.4
3.3
3.3

3.4
3.3
3.3

0.003
0.005

0.003
0.005

0.002
0.004

0.002
0.004

1014
1015
1014
1015

1014

1014

1014

1015
1014
1015

1015
1014
1015

1015
1014
1015

N = no breakC = complete break,incl. hinge break H

15

Table 4: Properties of VESTAKEEP® compounds
Properties

Standard

Unit

VESTAKEEP 2000 CF30

Physical and thermal properties and fire behavior
Density
23 °C

ISO 1183g/cm 3

1.38°C

approx. 340

Melting range

DSC, 2nd heating

Melt volume-flow rate (MVR)

380 °C/5 kg
400 °C/10 kg

Temperature of deflection under loadMethod A
Method B

ISO 1133
ISO 11333

cm /10 min
cm 3/10 min

10
-

°C
°C

330
340

°C
°C

343
340

10-4 K-1

0.1

%

47

ISO 75-1/2
1.8 MPa
0.45 MPa
ISO 306

Vicat softening temperature
Method A
Method B

10 N
50 N
ISO 11359

Linear thermal expansion
23 °C–55 °C
longitudinal
Oxygen index
Flammability acc. UL94

Glow wire test

GWIT
GWFI

3.2 mm

ISO 4589

0.8 mm
1.6 mmIEC 60695
IEC 60695

2 mm
2 mm

IEC 60695-2-12/13
IEC 60695-2-12/13

V-0
V-0
°C

875
960

%
%

0.1
0.7

%

0.4

ISO 294-4

Mold shrinkage
in flow direction
in transverse direction
Water absorption, saturation

23 °C

ISO 62Mechanical properties
Tensile test

50 mm/min

ISO 527-1/-2

Stress at yield
Strain at yield

MPa
%
%

Strain at breakTensile test
Tensile strength
Strain at break

5 mm/minMPa%
ISO 527-1/-2

Tensile modulus
CHARPY impact strength

CHARPY notched impact strength

Electrical properties
Comparative tracking index
Test solution A
Electric strength

ISO 527-1/-2

23 °C-30 °CISO 179/1eU

23 °C-30 °CCTI

Volume resistance
Volume resistivity
Surface resistanceSpec. surface resistance

16

kJ/m

23000
2

45 C
45 C

ISO 179/1eA

kJ/m2
kJ/m2

9C
8C

IEC 60112--

IEC 60243-1

kV/mm
kV/mm

-

IEC 60250-

17

IEC 60250-

0.23

IEC 60093
IEC 60093
IEC 60093
IEC 60093

Ohm
Ohm*cm
Ohm
Ohm

105
106
105
106

100 drops value
K20/P50

50 Hz
1 kHz
1 MHz

Dissipation factor

MPa

kJ/m2

K20/K20
Relative permittivity

240
2

50 Hz
1 kHz
1 MHz

VESTAKEEP 4000 CF30

VESTAKEEP 2000 FC30

VESTAKEEP 4000 FC30

1.40

1.45

1.45

approx. 340

approx. 340

approx. 340

3

15
-

2.5
-

325
335

320
337

310
330

343
340

340
335

340
335

0.1

0.2

0.2

47

44

44

V-0
V-0

V-0
V-0

V-0
V-0

850
960

900
960

900
960

0.1
0.6

0.4
0.6

0.3
0.5

0.4

0.4

0.4

240
2

145
2

140
2

23000

11500

11500

60 C
60 C

40 C
40 C

45 C
45 C

10 C
9C

6C
5C

8C
7C

-

-

-

-

-

-

17

6.1
5.5
4.9

6.1
5.5
4.9

0.23

0.07
0.04
0.02

0.07
0.04
0.02

105

105

105

6

7

107
105
106

10
105
106

10
105
106

N = no breakC = complete break,incl. hinge break H

17

4 Processing
General Information

Injection molding

For injection molding and extrusion
processing, VESTAKEEP® polymers andcompounds are primarily processed in
granular form. Most standard screwmachines are suitable for this.The plasticating unit should be designed forprocess temperatures of up to 450 °C.
It may also be necessary to modify thecontroller, band heaters, and temperature sensors. In addition, we recommend that the instructions listed below
be observed when processing PEEK.

Plasticating Unit
Screw and barrelStandard screw (three-zone screw) with alength between 18 and 24 D are usuallysuitable. Zone breakdown: feed 55–60%, compression 20–25%, metering 20–25%. Flight depth ratio 2.0–2.5:1
The plasticating unit should be designed
so that the required metered volumes lie
between 30% and 70% of the maximum
possible shot volume. This will produce ahomogenous melt quality.

DryingVESTAKEEP® leaves the factory with amoisture content of less than 0.25 wt.%.
We nevertheless recommend additional
drying in order to obtain qualitatively
high-grade extrudates.
. Drying temperature: 150–160 °C. Drying time: 2–3 hours in the dry-air
dryer or vacuum furnace. A drying cabinet is good for base powders.
We also recommend 4 or more hours
for film applications. Hopper: heated or thermally insulated. Max. residual moisture: < 0.02
weight-% is recommended for basepowders and granules
Suggestions:. The saturation temperature of the dryer
should be at least -30 °C. Convey the granules with dried air exclusively. Use PU hoses for conveying, not PVC
hoses

18

Back flow valve
Commercially available three-piece backflow valves are used. Machine manufacturers provide a wide choice of different
designs. Rapid, reproducible closing of thevalve during injection is an indispensable
requirement for ensuring that quality andweight of the molded part remain constant.
NozzleIn general, free-flow nozzles are recommended. A slight easing of the decompression of about 3 to 5 mm will counteract thedischarge of the melt from the nozzle bore.
But decompression distances that are toolong will cause air to become trapped,
resulting in burned spots and gate marks.
Shut-off nozzles are less suitable because
loss of injection pressure must be expected
because of the poorer melt transport. It isalso possible for thermal damage to occur
in the existing "dead corners” because ofretention times being too long.
In all of the nozzle types used, it is necessary
to make sure that the heat output is sufficient. To prevent "freeze-off” of the nozzle
and formation of a "cold slug” when thesprue bush is adjacent to the injection unit,
the band heater should cover the entire
length of the die body.
In order to demold a sprue gate without
trouble, the outlet diameter of the machine
nozzle should be approximately 0.5 to
1 mm smaller than the bore diameter ofthe sprue bush.

It is also important that the radius of themachine nozzle is smaller than that of thesprue bush (e.g. nozzle radius = 35 mm,
sprue-bush radius = 40 mm).
Injection unit
Screws made of corrosion-protected andwear-protected high-alloy PM steels areusually used to process VESTAKEEP® within the injection cylinder. We recommend abimetallic design for the injection cylinder.
Since VESTAKEEP® has a strong tendency
to adhere to metallic surfaces, it is possible
for cracks to form in the nitrided layer ofnitrided screw surfaces during cooling.
The adhesion can be so strong that thenitride layer can peel off from the steel
core.
Metallic areas that come into direct contact with the melt should be highly polished to prevent deposits that could cause
thermal decomposition due to the increased retention time. In order to obtain
good conveying action by the screw, thefriction between the granules and the cylinder wall must be greater than that between the granules and the screw surface.

Cleaning
GeneralRemove other polymers completely fromthe plasticating unit before processing
VESTAKEEP® compounds. This can beaccomplished either by cleaning the cylinder and screw mechanically or by using
suitable cleaning materials. These arematerials that are thermally stable up to
approximately 380 °C. One suitable material is a high-viscosity PC containing
glass fibers (e.g., MAKROLON® 8345,
ASACLEAN®). Other suitable materials
include PES, PEI and, with limitations,high-viscosity PP. Since PP decomposesat these temperatures, effective ventilation is important.

Material change over to VESTAKEEP®
1. Set the temperature to the temperaturenormally used when processing thematerial to be removed.
2. Introduce the cleaning material andcontinue rinsing until no traces of thematerial to be removed can be detected.
3. Run the screw dry.
4. Set the cylinder temperatures to thevalues required for PEEK processing.
5. When the temperatures have been
attained, feed the material through thecylinder long enough that a clean melt
is present.
Cleaning while shutting down theinjection molding machine
Completely remove the PEEK melt fromthe cylinder before processing anothermaterial. There exists the danger that themelt could solidify with the nitride layerof the cylinder and screw while cooling.
Because of the high adhesive forces, thislayer could peel and damage the screw(see “Tool steel”). This means that thecylinder may be allowed to cool only after
cleaning and careful rinsing.
Cleaning process:1. Remove material form the injection
molding machine (hopper).
2. Introduce the cleaning material andcontinue rinsing until there are nolonger any visible traces of the PEEK
material.
3. Reduce cylinder temperatures to alower temperature (350 °C) that is still
acceptable for PEEK.
4. Continue rinsing with the cleaningmaterial until the actual cylinder temperature drops below 300 °C. An evenlower temperature (< 250 °C) may berequired, depending on cleaning material.
5. Possibility of mechanical cleaning

19Clamping unit
Mold clamping force
The required clamping force depends on
the size of the expected molding area
(sprue area plus article area) and theresulting internal pressure of the mold.
An adequate clamping force must be
ensured since the injection pressures of
100 to 200 MPa are very high in comparison with other projects.
The production of precision parts andinjection molded articles that have large
flow-distance/wall-thickness ratios involve pressures in excess of 200 MPa.

Tool
Tool steel
For the cavity, use steel grades that still
have a hardness of about 52 to 54 HRC
at the high processing temperatures, forexample. 1.2343 ESU (X38CrMoV51) - easy topolish. 1.2379 (X155CrVMo121) - core hardened. 1.2083 (X42Cr13 ) - core hardened,corrosion-resistant. 1.2316 (X38CrMo16) – non-rusting
steel, easy to polish
Wall thickness of molded parts
Minimum wall thickness:. approx. 1 mm for unfilled PEEK molding compounds. approx. 1.5 mm for filled PEEK molding
compounds
Flow-distance/wall-thickness ratio
Maximum attainable flow distance/wallthickness ratios for unfilled materials and2 mm wall thickness up to 200 : 1 (conditions: melt temperature 380 °C, moldtemperature 180 °C, injection pressure
140 MPa)

20

Sprue. Minimum diameter: 4 mm, for direct
gating 1 to 1.5 times the thickness ofthe molded article. Demolding draft angle: at least 2°. Ejector claw: special for direct gating. Manifold: round or trapezoidal (crosssection as large as possible for small
surface)
Gate
Dependent on melt volume, number ofcavities, component geometry; nearly
all common systems are suitable; but
small tunnel gates freeze off quickly andare preferably used when short holdingpressure times are required; however;thin flow areas should be avoided.
Minimum gate diameter:. approx. 1.0 mm for unfilled materials. approx. 2.0 mm for reinforced materials
Hot runner system
We recommend exclusively nozzles thathave good external heating with a heatconducting torpedo in the nozzle tip forprocessing VESTAKEEP® with hot runnersystems. These systems generally feature
low pressure losses and clearly definedflow-channel cross sections that enhanceflow.
For reinforced VESTAKEEP® grades, heatconducting torpedoes made of hard metaloffer adequate protection against wear.
Needle shut-off systems can also be usedin practice. However, we do not recommend them for compounds that containfillers (e.g. GF, CF).
Frequently non-corrosive types of steel
with increased chrome content (1.2316,
see Mold) are used to process PEEK in hot
runner systems. They must permanently
maintain process temperatures up to
450 °C.
To achieve an exact thermal separation
between nozzle and mold, it is necessary
to correctly follow the manufacturer’s
instructions when implementing the gate
geometry. This is important in order toavoid surface defects and unclean separation points.

The feed-point diameter for reinforced
compounds should be around 0.2 to
0.3 mm larger than in the case of unreinforced grades.
The hot runner controllers should be able
to correct temperature deviations of up to+/- 1 °C.
To keep pressure losses as small as possible, the gate openings should be dimensioned as large as possible.
Many manufacturers can calculate pressure losses in the hot runner based onmaterial data.
Venting
Venting slots in mold parting surface or,in particular, at the end of the runners cangenerally be incorporated 0.02 mm deep
without burr formation. If necessary, thedepth may be increased to 0.05 mm but itis then necessary to watch out for burr
formation.
Further support of venting by means ofappropriately fashioned ejector pins is
possible. Vent packages at critical pointsof confluence can also help prevent"burnings.” Compressed air in the cavity
can reach temperatures as high as 1000 °C
and result in damage to the molded part.
It is important to provide adequate ventilation in blind holes in particular, because
molded articles may otherwise not fillcompletely. Vent pins that can be easily
removed for cleaning are helpful.

Pressure gauge
We recommend the use of an internalpressure gauge to set the switching point
precisely.
Temperature control
Since mold surface temperatures can beas high as 220 °C, we recommend the useof oil-operated tempering devices. The
devices should be designed for operating
temperatures of up to 250 °C. Special
hoses that are approved for high operating
temperatures should be used. For themold feed system, tight threaded joints
are preferable to plug and couplingsystems.
It is also necessary to pay attention to the
maximum permissible operating temperatures of all seals (Viton®, Kalrez®)
within the mold as well as the seals in thehydraulic cylinders of core pullers.
Electrically heated injection molds, inwhich there is a much slower reaction totemperature changes because no heat isdissipated, can also be used.
The external surfaces of the mold can becovered with insulating plates to minimize loss of heat to the surroundings fromthermal radiation. We recommend theuse of heat-insulating plates between themachine support plates and mold.

21

Processing conditions
Cylinder and mold temperatures
We recommend the following melt temperatures to process VESTAKEEP® successfully:
Melt temperatures
VESTAKEEP®
1000 G 2000 G

3000 G

4000 G

4000 GF30

4000 FC30

4000 CF30

[°C]
360

[°C]
375

[°C]
380

[°C]
390

[°C]
390*

[°C]
400

[°C]
370

Set the cylinder temperature profile slightly rising with the feed temperature 10 to
20 °C lower than the last cylinder heat zone temperature.
The optimum melt temperature depends on various factors, such as the retention time in
the plasticizing cylinder and the wall thickness of the molded article. The melt temperatures recommended in the above table can be used as starting temperatures. They canbe increased by 10 to 20 °C for short residence times and thin wall thicknesses.
Typical values for cylinder and mold temperatures

VESTAKEEP® G
VESTAKEEP® CF

Nozzle[°C]

Zone 3[°C]

Zone 2[°C]

Zone 1[°C]

Hopper[°C]

Moldtemp. [°C]

370–380
400–410

360–380
390–410

360–370
390–400

350–360
380-39070–10070–100160-200
180-220

Select high temperatures to achieve a high degree of crystallization.
Screw speed
Peripheral screw speed
Rotational speed, e.g., #30 screw
50–100 rpm
Unfilled materials: 5–10 m/min
Reinforced materials: max. 6 m/min
60 rpmHigher speeds are not recommended because of the possibility of thermal overload ofthe melt caused by frictional heating from large local shear effects.

Back pressure
Back pressures between 2 and 8 MPa
improve the melt homogeneity. For reinforced VESTAKEEP® grades, we recommend a lower back pressure in order toprocess the fillers as gently as possible andobtain the mechanical properties.

Injection speed
The injection speed should be as high as
possible and therefore requires injection
pressures up to 250 MPa, depending on
the prevailing mold conditions (gatedimensioning, flashing, ventilation, etc.).
For short filling times, we recommend
storage machines.

Decompression
We recommend a decompression distanceof approx. 3 to 5 mm for melt ejection
from the nozzle.
*VESTAKEEP® compounds, which are filled with PTFE (FC grades), can release highly toxic and caustic gases at temperatures exceeding 380 °C.
If conditions leading to this decomposition are not avoidable, direct exposure of the employees must be prevented, e.g. by an efficient withdrawal of exhaust air.

22

Injection pressure
The injection molding machine should bedesigned for injection pressures up to
250 MPa, the required injection pressure
essentially depending on the melt andmold temperature and the flow-distance/
wall thickness ratio of the component.
Holding pressure
As a rule, holding pressures of up to 120
MPa in combination with an optimized
holding-pressure time should be sufficient
to produce components without sinkmarks. A melt cushion of 3 to 5 mm will
ensure adequate pressure transmission
from the injection cylinder to the cavity.
The gating must be dimension large
enough to allow the holding pressure toact upon the molded part for a sufficient
length of time.

Holding pressure time
Since VESTAKEEP® materials have a highsolidification point (TK approx. 345 °C),gates to the molded article can freeze off
prematurely. The optimum holding
pressure time must be established by determining the gate seal-off point. Holding
pressure times that are too short can resultin sink marks and voids because of an
insufficient supply of material comingfrom the plasticizing cylinder.
Production stops
For relatively short production stops (upto 1 hour), the material can be kept at
360 °C without any significant decomposition.
For downtimes longer than 1–3 hours,
the temperature should be dropped to
340 °C. The material possesses adequate
melt stability at this temperature.
When restarting, rinse the cylinder adequately and reject the first molded parts.
For interruptions lasting more than 3
hours, a cleaning is recommended. See“Cleaning.”

For measures to eliminate defects in injection molded parts see Table 5 on page 26.

Extrusion
Plasticating unit
ExtruderAs mentioned above, most standard screwmachines are suitable for PEEK processing provided that they can operate reliably
at the required processing temperatures.
Standard screws (three-zone screw) witha length between 18 and 24 D are normally suitable: Zone breakdown: feed
12 D, compression 4–6 D, metering 4–6 D
Flight depth ratio: 2–3:1
For screws and barrels, we recommend
sufficiently corrosion- and abrasionresistant steels and bimetals.

If conventionally nitrided parts are used,make sure that the VESTAKEEP® melt does
not cool on the surface and solidify on the
nitride layer. The adhesion can be sostrong that cracks will form and the nitride
layer can peel off from the steel core.

23

Processing temperatures
The optimum processing temperatures of PEEK depend on various factors, such as theviscosity of the compound and the technical parameters of the extrusion unit.
The material can be heated in the hopper to improve the melting characteristics of the
granules. The recommended temperatures lie in the range 140 °C–180 °C. If it is notpossible to heat the hopper, the granules can be fed warm. The temperatures of thefeed zone must be chosen on the basis of the viscosity and filler of the material. The
first heating zone should be heated to about 350 °C–360 °C. Conventional extrusion
exhibits a temperature profile similar to the following:
Typical processing temperatures for VESTAKEEP®

VESTAKEEP® G

Nozzle[°C]

Zone 3[°C]

Zone 2[°C]

Zone 1[°C]

Hopper[°C]

370–380

360–380

360–370

350–360

140–180

Mold
We recommend that you optimize theheating to achieve a uniformly high temperature distribution (e.g. die heating forflat sheet dies). In order to reach andmaintain these temperatures, it is important that thermal radiation be kept low.
If this is not possible, the mold should be
insulated with appropriate thermal insulation.
Metallic areas that come into direct contact with the melt should be highly polished to reduce the adhesion of the melt
to the metal, thus reducing the residence
time and less disturbing the flow of themelt.
Downstream unit
It is possible to obtain different properties
for the extrudate by tempering the downstream unit (chill roll, calendar and calibration temperatures). VESTAKEEP® is asemi-crystalline material whose properties(transparency, color, mechanics, etc.) arestrongly dependant on the cooling characteristics. If a semi-crystalline structure is tobe achieved, it is necessary to temper the
extrudate in the downstream unit, possibly
up to 200 °C and higher.

24

Material change-overFor a material change-over from other polymers to PEEK, it is necessary to rinse temperature-unstable materials completely out of
the cylinder and downstream units. Decomposition reactions and gas formation could
otherwise occur. In most cases, we recommend mechanical cleaning, however. See
the corresponding procedure in the Section"Mechanical cleaning”.
Material change-over to VESTAKEEP®
1. Extrude the cleaning material in accordance with the processing recommendations of the material manufacturer.
Rinse until there is no longer any traceof the material to be removed.
2. Run the screw dry.
3. Set to the temperatures required for
PEEK processing.
4. When the temperatures have been
attained, fill VESTAKEEP® into thematerial hopper and extrude until aclean melt is present.

Material change-over of
VESTAKEEP® to other polymers
Before another material can be processed,
it is necessary to completely remove the
PEEK melt from the cylinder. The compound to be processed next should be
insensitive to heat in order to avoid decomposition reactions and gas formation.
Cleaning
Remove other polymers completely fromthe plasticating unit before processing
VESTAKEEP® compounds. This can beaccomplished either by cleaning the cylinder and screw mechanically or by using
suitable cleaning materials. These arematerials that are thermally stable up to
approximately 380 °C. One suitable material is a high-viscosity PC containing
glass fibers (e.g., MAKROLON® 8345,
ASACLEAN®). Other suitable materials
include PES, PEI and, with limitations,high-viscosity PP. Since PP decomposes atthese temperatures, effective ventilation isimportant.

Cleaning process
1. Remove the material from the hopper.
2. Run the screw dry.
3. Feed in the cleaning material and continue extruding until there is no longer
any visible trace of the PEEK material.
Please observe the corresponding processing recommendations of the material manufacturer.
4. Reduce the cylinder temperatures to alower value that is still acceptable for
PEEK (350 °C) and, if necessary, reduce
further to the temperatures of thecleaning agent.
5. Continue to rinse with the cleaningmaterial until the typical temperaturesof the cleaning material have been
attained.
6. If necessary rinse with another material
that can be easily removed from themetal before mechanical cleaning.
7. Mechanical cleaning

Other processing instructions
For longer downtimes, the temperature
should be dropped to 340 °C. The material possesses adequate melt stability at
this temperature. For downtimes exceeding 3 hours cleaning is recommended.
See "Cleaning.”
If the VESTAKEEP® melt cools down within the cylinder, the compound will harden(similarly as in the case of PC). Because of
the high adhesive forces that arise, it ispossible, especially in the case of conventionally nitrided surfaces, that cracks willarise or even that the nitride layer will peeloff, raising the possibility of damage to thescrew (see "Tool steel").

25

Stresses
Flow line
Incompletely
filledToo little injected
Insufficient flux

p

p

p

p

p

q

Rotational speed of screwpq

Nozzle contact time

Overheating

Nozzle temperature

Brittleness

Mold temperature

Defect in the molding Possible cause

Melt temperature

Table 5: Measures to eliminate defects in PEEK injection molded partsqp

Mold design
Transparent edges/
dark regions

Mold temperature
too low

Cold plugs

Melt transitions withinpthe nozzle
Sink marks/voids

Inadequate time andpressure conditionsq

Mold design
Burn marks

Air trapped in cavity

Flashing

Clamping force too small/fitting

StreakingDull surfaces(Reinforced grades)p = increaseq = decrease.

= do
P = profile

26

accuracy of the mold halvesq

Overheated molding
compoundq

Humid materialpInsufficient injection speed
Shear on the melt too strong

q
q
p

q

q

p

p

q

p
q

p
p

p

q
q

q
q
p

P

Holding pressure

Injection pressure

Shot volume

Injection speed

Gate cross section

p
p

p

.
.

.
.
..
.

Dry the material

Clamping force

Improve venting of cavity

Move the gate position

Cycle time

q

.

p

.

27

5 Physiological and Toxicological Evaluationof VESTAKEEP® Compounds
The Environment, Health, Safety & Quality Department, which is responsible for
the High Performance Polymers Business
Unit, provides general information on the
toxicological properties of VESTAKEEP®
compounds and relevant analysis pertaining to their contact with foodstuffs. The
department is also responsible for providing information about product safety andproducing the EC Safety Data Sheets for
VESTAKEEP®. Please direct all questions
on the subject to the indicated contact
persons.
VESTAKEEP® compounds are water-insoluble, solid polymers that are largely inert
physiologically. No toxicity is expectedfrom single contact or even multiple contacts, because VESTAKEEP® products are
not absorbed either through the skin or
through the gastrointestinal tract. As in
the case of other inert dusts, exposure to
VESTAKEEP® dusts could possibly result inmechanical irritation in the upper respiratory passages and the mucous membranesof the eye. Irritation or sensitization of theskin is not expected. Based on our best
current understanding, VESTAKEEP®
does not have any adverse effects on man,animals, plants, or microorganisms.
Please direct any further questions regarding product safety to the indicatedcontact persons.

28

Food Contact – EU-Status
Uniform regulations for plastics that comeinto contact with foodstuffs exist at theEuropean level. The consolidated EU Directive 2002/72/EC and its amendments
apply. It lists approved monomers and,since December 31, 2006, approved
plastic additives as positive. In other words,
in Europe only approved monomers andadditives on the EU positive lists may comeinto contact with food. Nationally approved additives are no longer permitted.
However, nationally approved additives
that had been submitted to the EU Commission for approval prior to 12/31/06
constitute an exception. These additives
may continue to be used for food contact
beyond 12/31/06 during a transition
period until final evaluation and approvalby the EU Commission.
Unreinforced and glass fiber-reinforced
VESTAKEEP® compounds are approvedfor direct food contact in the European
Union because the monomers and additives on which they are based satisfy theabove Guideline and its updates.
Restrictive migration values must be observed on the finished article and, forglass fiber-reinforced VESTAKEEP®
grades, special marketing conditions andconditions of use must also be observed(principle of "Mutual Recognition”).

Food contact – FDA status

Medical applications

In the United States, the FDA Regulation
21 CFR 177.2415 covers plastics thatcome into contact with food. Since thepolymers on which the unreinforced andglass fiber-reinforced VESTAKEEP® compounds are based meet these regulations,these compounds are suitable for foodcontact applications in the United States
pursuant to Section 177.1415 for articles
intended for repeated use.

For medical applications, the European
approval procedure is laid down in Directive 93/42/EEC. The national implementation of this directive into German
law is the Medizinproduktegesetz (Medical Products Act) of August 1994. The
detailed procedure to be followed is
described in the pertinent internationaland national standards (e.g., ISO 10993,
DIN EN 30993-1). The DAB monographs(German Pharmacopoeia, current edition)or those of the European Pharmacopoeia(current edition 2008) can be used as
supplementary regulatory works to makethe decision in special cases.

For further information, please contact
the indicated contact persons.

In cases of doubt, the moldings or semifinished products must be investigated by
the manufacturer or user, taking the relevant conditions of use into consideration.
Our staff can provide you with information about their experiences with various
approval processes.

29

6 Information about Environmental
Compatibility and Safety
VESTAKEEP® compounds are non-hazardous substances that are not governed byany particular safety regulations. They
can be disposed of in accordance withlocal ordinances. Further information canbe found in the EC safety data sheet for
VESTAKEEP®. Recycling is, however, preferred and advisable for economic reasons.
No dangerous byproducts are formed if
VESTAKEEP® is processed properly. Careshould be taken, however, to ventilate theworking area properly. Detailed directions about handling VESTAKEEP® products can be found in the “Processing”
section of this brochure.
Degradation of the material during processing is shown by a discoloration of themelt. Degraded material should be quickly
removed from the machine and cooled
under water in order to minimize any
troublesome smells or fumes.
No pigments or additives containing cadmium are used.

30

VESTAKEEP® compounds are noncombustible. Flammable gases can be released atmelt temperatures above 450 °C. Since
the spectrum of crack and combustion
products greatly depends on the combustion conditions, it is not possible to makeany general statements here.
VESTAKEEP® compounds, which are filledwith PTFE (FC grades), can release highly
toxic and caustic gases at temperatures
exceeding 380 °C. If conditions leading
to this decomposition are not avoidable,
direct exposure of the employees must be
prevented, e.g. by an efficient withdrawal
of exhaust air. In addition to our instructions, please also comply with the safety
data sheet for the compound in question.
VESTAKEEP® compounds can be easily
recycled.The properties of the recyclates
are only slightly affected. For questions
regarding the recycling of VESTAKEEP®
compounds, please contact the indicatedcontact persons.

Integrated expertise: no region without direct contacts
Northern Germany, Benelux
Karsten Goldsteinphone +49 2365204790
mobile +49 1718130033
karsten.goldstein@evonik.com

NordicGöran Winnerstam
phone +46 40459500
mobile +46 706094570
goeran.winnerstam@evonik.com

Australia
Peter Gibson
phone +61 298914011
mobile +61 418270474
peter.gibson@evonik.com

Southern Germany, Iberia
Ludger Malmedy
phone +49 8251870157
mobile +49 1718130072
ludger.malmedy@evonik.com

PolandAndrzej Wolak
phone +48 223181007
mobile +48 603202152
andrzej.wolak@evonik.com

China
Shelley Deng
phone +86 2161191368
mobile +86 13816269507
shelley.deng@evonik.com

Central Germany
Achim Hiltrop
phone +49 2017988871
mobile +49 1718130045
achim.hiltrop@evonik.com

TurkeyMehmet Ali Ersudas
phone +90 2163959961255
mobile +90 5322311525
ali.ersudas@evonik.com

India
Ashok Bandellaphone +91 2256307070
mobile +91 9820211866
ashok.bandella@evonik.com

Austria, Switzerland
Beat Bertschinger
phone +41 19380665
mobile +41 794453703
beat.bertschinger@evonik.com

UK, Eire
Hameem Yasin
phone +44 1214432016
mobile +44 7890536447
hameem.yasin@evonik.com

Japan
Katsumi Sawada
phone +81 353246332
mobile +81 9080018015
k.sawada@daicel-evonik.com

Czech. Republic, Slovakia
Miroslav Sarmanphone +420 272111817
mobile +420 602336106
miroslav.sarman@evonik.com

Americas
Fernando Jorgephone +1 9735418397
mobile +1 9738707778
fernando.jorge@evonik.com

Korea
Hongil Kim
phone +82 325102442
mobile +82 112520181
hongil.kim@evonik.com

FranceGéraud Apchin
phone +33 139757985
mobile +33 607244714
geraud.apchin@evonik.com

BrazilGermano Coelho
phone +55 113146 4150
mobile +55 1181427897
germano.coelho@evonik.com

.

Italy
Roberto Sacchi
phone +39 0371219363
mobile +39 3356840731
roberto.sacchi@evonik.com.
.. .. .
...
.
.
p

p
p
p

.

p
p
p

p

p
pp

p

p

direct contacts

p further contacts

p
p

p

.
..
.

p

p

p

p

p

p

p

.

p

.
31

Your global experts:
Aerospace, rail cars
Martin Risthausmartin.risthaus@evonik.com
AutomotiveFrank Lorenz
frank.lorenz@evonik.com
Electronics, engineering,semiconductors, stock shapes
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uwe.kannengiesser@evonik.com
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Your global contacts see insideThis information and all further technical advice arebased on Evonik Degussa’s present knowledge andexperience. However, Evonik Degussa assumes noliability for providing such information and advice
including the extent to which such information andadvice may relate to existing third party intellectual
property rights, especially patent rights. In particular, Evonik Degussa disclaims all conditions andwarranties, whether expressed or implied, including
the implied warranties of fitness for a particular purpose or merchantability. Evonik Degussa shall not be
responsible for consequential, indirect or incidental
damages (including loss of profits) of any kind.
Evonik Degussa reserves the right to make anychanges according to technological progress or further developments. It is the customer’s responsibility
and obligation to carefully inspect and test any incoming goods. Performance of the product(s) described herein should be verified by testing andcarried out only by qualified experts. It is the sole
responsibility of the customer to carry out and arrange for any such testing. Reference to trade names
used by other companies is neither a recommendation, nor an endorsement of any product and does
not imply that similar products could not be used.
®
= registered trademark

Evonik Degussa GmbHHigh Performance Polymers
45764 Marl
Germany

03/lau/1000/e

phone +49 2365 49-9878
fax +49 2365 49-5992
www.evonik.com/hp
www.vestakeep.com