THE ROLE OF MOLECULAR ARCHITECTURE ON RHEOLOGICAL PROPERTIES AND ITS EFFECT ON FILM-CASTING PERFORMANCE

摘要

While retaining the same macromolecular repeat unit, processing characteristics may be altered simply by changes in the architectural structure of the molecule. The effect of long-chain branching, LCB, and ultimately strain-hardening is evaluated on the cast film process. Sparsely LCB polyethylenes based on LLDPE and HDPE systems are evaluated with respect to film width profiles, edge-bead profiles, and rheological response. Increases in strain-hardening behavior promote a reduction in film necking and conversely an increase in film thinning.