HDPE UHMWPE examples of stress at yield retention versus sub-zero temperatures C

The glass transition temperature of PE by DSC measurements is -110°C. The glass transition temperatures by DMTA measurements can be higher, depending on the frequency. These results relate to some grades only and cannot be generalized. 

Polyethylenes are whitish and translucent to opaque according to the density and grade. The refractive index varies with the density and type of polyethylene, for example  

These results relate to some grades only and cannot be generalized. 

Crystallinity and molecular orientation improve the mechanical properties but are harmful to notched impact resistance. 

High density and UHMW polyethylenes are used to make antifriction parts. The coefficients of friction are low but the moduli, hardnesses and softening temperatures are weak, which limits the loads and PV factors. 

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Figure 4.2. HDPE UHMWPE examples of stress at yield retention (%) versus sub-zero temperatures (°C)...

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