Method for pre-expanding elongated segments of strands of expandable styrene polymercompositions

Claim 1

A PROCESS WHICH COMPRISES INDIVIDUALLY FOAMING ELONGATED SEGEMENTS OF STRANDS, INCLUDING CURVED, BENT, TWISTED AND CURLED SEGMENTS OF STGRANDS, RIBBONS, BANDS, TAPES, AND RODS OF A NORMALLY SOLID EXPANSIBLE STYRENO POLYMER COMPOSITION CONTAINING A VOLATILE ORGANIC FLUID FOAMING AGENT, BOILING A TEMPERATURES BELOW THE HEAT DISTORATION TEMPERATURE OF THE STYRENE POLYMER, UNIFORMLY DISTRIBUTED THROUGHOUT, SAID ELONGATED SEGMENTS EACH HAVING A CROSS-SECTIONAL AREA EQUIVALENT TO THE AREA OF A CIRCLE HAVING A DIAMETER OF FROM 0.01 TO 0.2 INCH AND A RATION OF LENGTH TO CROSS-SECTIONAL AREA WITHIN THE RANGE OF FROM ABOUT 8:1 TO ABOUT 200:1, BY SUPPLYING SAID ELONGATED SEGMENTS TO A ROTATING FEEDER, TUMBLING THE ELONGATED SEGMENTS ON A SCREEN HAVING A MESH SIZE THE SMALLEST DIMENSION OF WHICH IS GREATER THAN THE LARGEST CROSS-SECTION DIMENSION, BUT NOT MORE THAN ONE-HALF THE LENGTH, OF SAID ELONGATED SEGMENTS, AND THE LARGEST DIMENSION OF SAID SCREEN MESH BEING LESS THAN THE LENGTH OF SAID SEGMENTS, SUFFICIENT TO ALLOW PASSAGE OF INDIVIDUAL SEGMENTS OF SAID EXPANSIBLE STYRENE POLYMER COMPOSITION THERETHROUGH, CONTINUOUSLY COLLECTING THE SEGMENTS PASSING THROUGH THE SCREEN OF THE ROTATING FEEDER ON A POROUS BELT WHICH RETAINS THE SEGMENTS THEREON, TRANSPORTING SAID SEGMENTS INTO A HEATING ZONE AND FOAMING THE EXPANSIBLE SYTRENE POLYMER COMPOSITION SEGMENTS BY HEATING THE SAME TO A TEMPERATURE BETWEEN 90* AND 110*C. BY CONTACTING SAID EXPANSIBLE SEGMENTS IN SAID HEATING ZONE WITH A HEATED NONSOLVENT FLUID, AND REMOVING THE FOAMED SEGMENTS FROM SAID HEATING ZONE.