Molecular properties and behavior of polyolefin solutions modified under conditions of solid-phase extrusion

Variations in the molecular characteristics of polyolefins modified under t he conditions of solid-state extrusion were studied by gel-permeation chrom atography. It was shown that the molecular mass of PP modified by polar com onomers increases by several times. However, the molecular mass of PE decre ases under the same conditions of mechanochemical modification. This differ ence may be explained by either different mechanisms of solid-state modific ation of PP and PE or formation of macromolecular associates in the solutio ns of modified polyolefins, as confirmed by the study of their rheological behavior.