Ultra-drawing behaviour has been studied by comparison of the gel-like spherulite pressing method and the gel-casting method using two kinds of specimens prepared from 2.0 wt% solution of ultra-high-molecular-weight polyethylene. The only major difference between the specimens is the cooling rate of solution. The influence of chain entanglement density in an undrawn specimen on the increase in strength and modulus with ultra-drawing has been discussed. The higher chain entanglement density of the undrawn specimen is the reason for the slopes of strength and modulus versus draw ratio being steeper in the gel-casting method. However, it was found that the differences in the above slopes between the two methods could not be explained by the changes in crystalline orientation and crystalline size with ultra-drawing.
All Science Journal Classification (ASJC) codes
- Organic Chemistry
- Polymers and Plastics
- Materials Chemistry