METHOD OF PREPARING POLYMER MATERIALS WITH SPECIFIED POROSITY VIA TREATMENT WITH CARBON DIOXIDE IN SUPERCRITICAL STATE FOLLOWED BY HEAT TREATMENT AT ATMOSPHERIC PRESSURE

摘要

FIELD: polymer materials.;SUBSTANCE: method is comprised in saturating polymer material sample, placed in high-pressure cell, with carbon dioxide under supercritical conditions at pressure 250 atm and temperature 40-120°C, cooling the cell to room temperature and slowly lowering pressure to its atmospheric value. Foaming of polymer sample saturated with carbon dioxide under supercritical conditions proceeds during 60 min of further heat treatment at atmospheric pressure. Final porosity of polymer sample is determined by heat treatment temperature.;EFFECT: essentially preserved mechanical properties of initial polymer due to that, during heat treatment operation, outside layer of CO₂-saturated polymer sample is foamed.;9 dwg, 1 tbl, 6 ex