Crystallization of Polymer Mixtures in the Course of Their Solution-Enhanced Dispersion by Supercritical Fluids

Abstract

The characteristics of phase equilibria for systems including toluene, supercritical CO₂, and ethylene–vinyl acetate copolymers (EVACs) were studied experimentally. Solution enhanced co-dispersion of EVAC and low-density polyethylene mixtures by supercritical fluids (SEDS) was performed under pressures of 8.0–25.0 MPa at 313, 323, and 333 K. The comparison of melting and crystallization in the resulting copolymer mixtures with those in the same-composition mixtures obtained by melt mixing showed SEDS to result in an increase in the degree of crystallinity of the polymer mixtures.