Polypenco is a genericized trademark term for Polyoxymethylene, a synthetic acetal thermoplastic material.

MechanicalASTM Test MethodValueUnits
Strength to Weight Ratio--ksi
Specific Gravity @73 FD7921.15-
Tensile Strength @73 F, (ult)/(yld)D63811,500 (ult)psi
Tensile Modulus of Elasticity @73 FD638425,000psi
Tensile Elongation at Break @73 FD63850%
Flexural Strength @73 FD79015,000psi
Flexural Modulus of Elasticity @73 FD79045,000psi
Shear Strength @73 FD73210,000psi
Comprehensive Strength, (% Deformation) @73 FD69512,500 (10)psi
Comprehensive Modulus of Elasticity @73 FD695420,000psi
Hardness, Rockwell, Scale as noted @73 FD785M85 (R115)-
Hardness, Durometer, Shore D @73 FD2240D80-
Izod Impact, (Notched) @73 FD256 Type A0.6ft-lb/in of notch
Coefficient of Friction, (Dry vs Steel) Dynamic-0.25-
Limiting PV, (with 4 to 1 factor of safety applied)-2,700psi-ft/min
ThermalASTM Test MethodValueUnits
Coefficient of Linear Thermal Expansion @73 FE-831 (TMA)5.5 E-05in/in/F
Heat Deflection Temperature @264 psiD648200F
Tg-Glass transition termperature, (Amorphous)D3418-F
Melting Point, (VS=Vicat Softening Temp.)D3418500F
Continuous Service Temperature in Air, (Max.)-210F
Thermal Conductivity-1.7BTU-in/hr-ft2-F
ElectricASTM Test MethodValueUnits
Dielectric Strength, Short TermD149400Volts/mil
Volume ResistivityD2574.5 E+13ohm-cm
Dielectric Constant @10E6 HzD1503.6-
Dissipation Factor @10E6 HzD1500.020-
Flammability @3.1 mm unless notedUL94V-2-
H2OASTM Test MethodValueUnits
Water Absorption, Immersion, 24 hoursD570(7)0.30% by weight
Water Absorption, SaturationD570(7)7.00% by weight