PK – Polyketone PK
AKROTEK® PK-VM natural (4774)PK-VM natural (4774) is an unreinforced Polyketone with high flowability. The outstanding friction and wear properties enable the use for demanding components exposed to tribological stress. PK is characterized by its outstanding media resistance, which qualifies it to be used for components that are in contact with chemicals. The most important markets for AKROTEK® PK are the automotive and furniture industry and mechanical engineering.
Properties
Tensile Modulus Tensile Strength Impact Strength-
Mechanical Properties
Tensile modulus (1 mm/min | ISO 527-2) d.a.m. 1500 MPa conditioned 1500 MPa
Stress at yield (50 mm/min | ISO 527-2) d.a.m. 60 MPa conditioned 60 MPa
Strain at break (50 mm/min | ISO 527-2) d.a.m. > 200 % conditioned > 200 %
Flexural modulus (2 mm/min | ISO 178) d.a.m. 1900 MPa conditioned 1500 MPa
Flexural strength (2 mm/min | ISO 178) d.a.m. 70 MPa conditioned 70 MPa
Charpy impact strength (23°C | ISO 179-1/1eU) d.a.m. n.b. conditioned n.b.
Charpy impact strength (-30°C | ISO 179-1/1eU) d.a.m. n.b.
Charpy notched impact strength (23°C | ISO 179-1/1eA) d.a.m. 10 kJ/m² conditioned 10 kJ/m²
Charpy notched impact strength (-30°C | ISO 179-1/1eA) d.a.m. 3,5 kJ/m²
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Thermal Properties
Temperature of deflection under load HDT/A (1,8 MPa | ISO 75) 100 °C
Temperature of deflection under load HDT/B (0,45 MPa | ISO 75) 190 °C
Melting temperature (DSC, 10K/min | DIN EN ISO 11357-3) 220 °C
Coefficent of linear thermal expansion, parallel (23°C bis 80°C | ISO 11359-1/2) 1,11 1,0E-4/K
Coefficent of linear thermal expansion, transverse (23°C bis 80°C | ISO 11359-1/2) 1,11 1,0E-4/K
Thermal conductivity (DIN 52612) 0,255 W/mK
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Flammability
Burning rate (UL 94) 1,6mm Wall thickness HB Class
Burning rate (<100 mm/min) (> 1 mm Thickness | FMVSS 302) +
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General properties
Density (23°C | ISO 1183) 1,24 g/cm³
Humidity absorption (70°C, 62% r.H. | ISO 1110) 0,8 - 0,9 %
Molding shrinkage (flow | ISO 294-4) 1,7 - 1,9 %
Molding shrinkage (transverse | ISO 294-4) 1,9 - 2,1 %
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Electrical Properties
Volume resistivity (IEC 60093) d.a.m. 1,0E+13 Ω · cm conditioned 1,0E+10 Ω · cm
Volume resistivity (DIN EN 62631-3-1) d.a.m. 1,0E+13 Ω · cm conditioned 1,0E+10 Ω · cm
Surface resistivity (DIN EN 62631-3-2) d.a.m. 1,0E+13 Ω conditioned 1,0E+10 Ω
Comparative tracking index (Test liquid A | IEC 60112) 600 V
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Rheological Properties
MVR (240°C/2,16kg | ISO 1133) 60 cm³/10min
Processing information
The listed values are recommendations. Higher values should be used for higher glass loadings. We recommend only de-humidifying or vacuum dryers. Extensive drying can cause filling problems and surface defects.
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Drying time | 0 - 4 h |
| Drying temperature (τ ≤ -30°C) | 80°C | |
| Processing moisture | 0,02 - 0,1% | |
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Feed section | 60 - 80°C |
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Temperature zone 1 - Zone 4 | 220 - 250°C |
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Nozzle temperature | 230 - 250°C |
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Melt temperature | 230 - 250°C |
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Mold temperature | 60 - 120°C |
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Holding pressure, spec. | 300 - 800 bar |
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Back pressure, spec. | 30 - 70 bar |
| Injection speed | medium to high | |
| Screw speed | 8 - 15 m/min | |
Warning
Polyketones crosslink depending on time and temperature, crosslinking is noticed by an increase of viscosity and/or dark spots in natural colored compounds. The melt temperature should be at or below 260 °C and under no circumstances go beyond 270 °C because crosslinking speed will increase. The residence time in the barrel including the hot runner should not exceed 10 min. If interruptions of more than 10 minutes are expected, the barrel and hot runner need to be purged and cleaned with polyolefins. The molding machine needs to be purged with polyolefines before and after processing of AKROTEK® PK! There is a risk of cross linking caused by reactions with POM or PA as well as unsuitable masterbatches! Crosslinking is noticed by an increase of viscosity and or dark spots in natural colored compounds. In this case purge immediately with polyolefines.
Disclaimer
All specifications and information given on this website are based on our current knowledge and experience. A legally binding promise of certain characteristics or suitability for a concrete individual case cannot be derived from this information. The information supplied here is not intended to release processors and users from the responsibility of carrying out their own tests and inspections in each concrete individual case. AKRO®, AKROMID®, AKROLEN®, AKROLOY®, AKROTEK®, ICX® and PRECITE® are registered trademarks of the Feddersen Group.
