Thermal and mechanical properties of cross-linked and uncross-linked linear low-density polyethylene-wax blends

The influence of the wax content and different concentrations of the crosslinking agent on the thermal and mechanical properties of linear low-density polyethylene-wax blends has been investigated. It was found that an increase in wax content induces an increase in elastic modulus and yield stress of the blends. This is a consequence of the higher crystallinity of the blends in the presence of a higher amount of wax. The average tie chain concentration in the blends is estimated in order to explain detrimental effects of the wax on the ultimate properties. A significant correlation was found between stress and strain at break and the concentration of tie chains. Cross-linking improves the ultimate properties of the blends and pure polyethylene. On the other hand, because of its low molecular weight, thermal stability decreases with an increase in wax content and this trend remains unchanged after crosslinking. (C) 2002 Elsevier Science Ltd. All rights reserved.