Process for preparing microporous opencelled cellular polymeric structures
Abstract
Abstract A PROCESS FOR PREPARING MICROPOROUS OPEN-CELLED CELLULAR POLYMERIC STRUCTURES WHICH COMPRISES (A) DISSOLVING THE STARTING POLYMER IN A MIXTURE COMPRISING CHLOROFLUOROCARBON SOLVENT AND A COSOLVENT SELECTED FROM METHANOL, ETHANOL, ISOPROPANOL, T-BUTANOL, DIMETHYLFORMAMIDE, DIMETHYLACETAMIDE, DIOXANE, TRIOXANE, DIMETHYLSULFOXIDE, TETRAHYDROFURAN, ACETONE, METHYLETHYL KETONE, HEXAMETHYL PHOAPHORAMIDE, ACETIC ACID, BUTYROLACTONE, N-METHYLPYRROLIDONE, PYRIDINE, MORPHOLINE, METHYL CELLOSOLVE, ETHYL CELLOSOLVE, PROPYL CELLOSOLVE AND A MIXTURE OF ANY OF SAID COSOLVENTS TO FORM A POLYMER SOLUTION; (B) ADDING WATER IN THE AMOUNT OF AT LEAST 10 VOLUME PERCENT OF THE POLYMER SOLUTION THERETO AT A TEMPERATURE BELOW THE ATMOSPHERIC BOILING POINT OF THE SOLVENTS BUT GREATER THAN 0*C.; (C) SEPARATING THE RESULTANT POLYMERCHLOROFLUOROCARBON PHASE; AND (D) REMOVING THE CHLOROFLUOROCARBON FROM THE SEPARATED POLYMER-CHLOROFLUOROCARBON PHASE.
Inventors
- 👤 F Jenkins
Bibliographic Details
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