Role of Crystallinity in Retention of Polymer Particle Morphology in the Presence of Compressed Carbon Dioxide

Abstract

The effects of compressed carbon dioxide absorption into poly( l -lactide), poly( dl -lactide), poly(glycolide), and their copolymers were observed using EPR and mechanical creep experiments to determine the correlation between the glass transition pressure and material failure pressure. Results show polymers can retain particle morphology above the carbon dioxide suppressed glass transition pressure because of a moderate crystalline volume fraction that reduces creep rates enough to limit particle agglomeration during precipitation with a compressed antisolvent.