Crystalline isotactic polystyrene fibers

Claim 1

A PROCESS FOR THE PRODUCTION OF HIGHLY CRYSTALLINE ISOTACTIC POLYSTYENE FILAMENTS WHICH COMPRISES POLYMERIZING STYRENE IN AN INERT ORGENIC DILUENT TO A SOLID, SUBSTANTIALLY INSOLUBLE, HIGHLY CRYSTALLINE ISOTACTIC POLYSTYRENE; PYROLYZING SAID HIGHLY CRYSTALLINE ISOTACTIC POLYSTYRENE AT TEMPERATURES OF FROM ABOUT 300* C. TO ABOUT 450* C. TO PRODUCE AN AMORPHOUS ISOTACTIC POLYSTKYRENE HAVING A MELT INDEX IN THE RANGE OF FROM ABOUT 0.01 TO ABOUT 5 DECIGRAMS PER MINUTE AND IMMEDIATELY AFTER THE PYROLYSIS QUENCHING THE PYROLYZED ISOTACTIC POLYSTYRENE AND RECOVERING A SOLUBLE AND SUBSTANTIALLY AMORPHOUS ISOTACTIC POLYSTYRENE HAVING A MELT INDEX IN SAID RANGE; EXTRUDING AN ORGANIC SOLVENT SOLUTION OF SAID AMORPHOUS ISOTACTIC POLYSYRENE AT A TEMPERATURE OF FROM ABOUT 50* C. TO ABOUT 100* C., SAID SOLUTION HAVING AN AMORPHOUS ISOTACTIC POLYSTRENE CONTENT OF FROM ABOUT 15% TO ABOUT 35% BY WEIGHT AND A SOLUTION VISCOSITY OF FROM ABOUT 1,000 TO ABOUT 20,000 CENTIPOISES; COAGULATING THE EXTRUDED AMORPHOUS ISOTACTIC POLYSTYRENE FILAMENTS IN A COAGULATING BATH CONTAINING A COAGULANT WHICH IS A SOLVENT FOR THE SOLVENT OF THE AMORPHOUS ISOTACTIC POLYSTRENE SOLUTION BUT WHICH IS NOT A SOLVENT FOR THE AMORPHOUS ISOTACTIC POLYSTYRENE, THEREBY PRODUCING FILAMENTS HAVING FROM ABOUT 5% TO ABOUT 20% RESIDUAL SOLUTION SOLVENT ON THE WEIGHT OF THE FIBER IN THE EXTURDED AMORPHOUS ISOTACTIC POLYSTYRENE FILAMENT; STRETCHING THE EXTRUDED AMORPHOUS ISOTACTIC POLYSTYRENE FILAMENT IN AN AMOUNT UP TO ABOUT 500% TO ORIENT THE MOLECULES AND RESTORE CRYSTALLINITY TO THE ISOTACTIC POLYSTYRENE TILAMENT WHILE IT STILL CONTAINS FROM ABOUT 5% TO ABOUT 20% BY WEIGHT RESIDUAL SOLUTION SOLVENT IN THE AMORPHOUS ISOTACTIC POLYSTYRENE; AND REMOVING THE RESIDUAL SOLUTION SOLVENT FROM THE MENT AT A TEMPERATURE BELOW THE FUSION TEMPERATURE OF THE CRYSTALLINE ISOTACTIC POLYSTYRENE FILAMENT.