Production of high density polyethylene composition containing organic peroxide cross-linking agent

Claim 1

A PROCESS FOR PRODUCING A SUBSTANTIALLY COMPLETELY UNCROSSLINKED POLYMERIC COMPOSITION WHICH IS CAPABLE OF BEING FABRICATED AND EXTRUDED BY CONVENTIAL PLASTIC WORKING APPARATUS AND STRENGTHENED BY CROSSLINKING ON SUBSEQUENT HEAT TREATMENT, WHICH COMPRISES FLUXING AND MILLING LOW DENSITY POLYETHYLENE HAVING A SPECIFIC GRAVITY BETWEEN ABOUT 0.885 AND 0.92 AT A TEMPERATURE BELOW ABOUT 275* F. WHILE ADDING THERETO SUFFICIENT HIGH DENSITY POLYETHYLENE HAVING A DENSITY BETWEEN ABOUT 0.94 AND 0.96 TO PROVIDE A MIXTURE COMPRISING FROM ABOUT 60% TO ABOUT 90% HIGH DENSITY POLYETHYLENE, AND MILLING INTO SAID MIXTURE WHILE FLUXING AT A TEMPERATURE BELOW ABOUT 275* F. AND ORGANIC PEROXIDE CROSSLINKING AGENT WHICH CANNOT BE EXPOSED TO TEMPERATURES ABOVE 275* F. IN THE PRESENCE OF POLYETHYLENE WITHOUT EFFECTING CROSSLINKING THEREOF.