Melt characterization of ultra high molecular weight polyethylene using squeeze flow

A method for determining the melt viscosity and molecular weight of ultra high molecular weight polyethylene (UHMWPE) is described. The method, based on squeeze flow, was used to characterize seventeen UHM W‐PE samples varying in molecular weight from 0.6 × 10 6 to 5.1 × 10 6 and in viscosity from 2.9 × 10 6 to 3.4 × 10 9 poise. A correlation between melt viscosity and molecular weight was demonstrated, but the reliability of a molecular weight determination decreased somewhat as molecular weight increased. As a predictor of melt processability, the method provides the speed and simplicity heretofore lacking in UHMW‐PE characterization by solution viscosity while retaining high reproducibility.