article

Abstract

A simple rheological method is presented for estimating the transient degree of long chain branching, x, of a polymer melt undergoing the early stages of a crosslink inducing reactive modification. The model is tested on a series of polypropylenes of increasing x, all produced from the same linear precursor, in the presence of varied peroxide concentrations. The branching indices predicted from analysing the zero shear viscosity of the samples are in good agreement with those evaluated by a laborious combination of size exclusion chromatography with intrinsic viscosity measurements.

macromolecules, 36, 4685-4687, 2001

Rheological Characterisation of Long Chain Branching in a Melt of Evolving Molecular Architecture