Short Name

PA12

Name

Polyamide 12

Group

ETP - Engineering Thermoplastics

General Properties

Chemical Formula

Structural Formula

Glass Transition Temperature

40 to 50 °C

Melting Temperature

170 to 180 °C

Melting Enthalpy

95 J/g

Decomposition Temperature

465 to 475 °C

Young's Modulus

1400 MPa

Coefficient of Linear Thermal Expansion

120 to 140 *10¯6/K

Specific Heat Capacity

1.17 to 1.26 J/(g*K)

Thermal Conductivity

0.22 to 0.24 W/(m*K)

Density

1.01 to 1.04 g/cm³

Morphology

Semi-crystalline thermoplastic

General properties

High impact strength. Good chemical resistance. Very good stress cracking resistance. Good sliding-friction behavior

Processing

Extrusion

Applications

Mechanical and apparatus engineering (e.g., bearing and drive elements in humid environments requiring high stability). Automotive engineering. Electrical engineering. Packaging. Medical engineering

Internet Links

In this measurement, evaporation of water occurred at 94°C (peak temperature 1st heating, blue). The shift in the position of the glass transition in the 2nd heating (green, (Tg of 43°C – midpoint with a Δcp value of 0.11 J/(g·K)) after water evaporation was smaller than that on page 95. The cooling rate selected in the experiment (in this case 10 K/min) was lower than the cooling rates polymer granulates generally experience during production. Therefore, the amorphous content of the sample was lower in the 2nd heating. This thesis is confirmed by the relatively high step height (Δcp) of the glass transition in the 1st heating (blue) as well as the exothermal post-crystallization (peak temperature: 159°C, crystallization enthalpy: 2.2 J/g) that occurred immediately prior to melting.
The endothermal melting effect at 178°C (peak temperature, 2nd heating) exhibited a melting enthalpy of approx. 34 J/g.