Effects of Vinyl Chain-Ends on the Melt Viscoelastic Properties of Radiation Crosslinked Polyethylene

Abstract

This paper discusses the structural changes and summarizes the uniaxial melt extensional properties of low density polyethylene (LDPE) after it has been subjected to high energy radiation. Two LDPE resins were selected with similar characteristics except that one (LDPE-1) had a much higher level of unsaturated vinyl change ends. The vinyl chain ends in LDPE-1 were found to be highly active during the radiation-induced crosslinking reactions, result ing in the formation of a network polymer with improved network homogeneity and melt extensional properties. This improvement is expected to benefit sev eral major PE applications such as foam, film and deep-draw thermoforming.