DECROSSLINKING OF CROSSLINKED POLYETHYLENES WERE PERFORMED IN A COROTATING TWIN SCREW EXTRUDER USING METHANOL AS RECYCLING AGENT. THE GOAL WAS THE INVESTIGATION OF THE INFLUENCE OF DIFFERENT PARAMETERS SUCH AS TEMPERATURE PROFILE OF EXTRUDER, SCREW ROTATION SPEED AND PRESENCE OF ALCOHOL ON QUALITY OF RECYCLED PE. IT WAS FOUND THAT BY INCREASING THE TEMPERATURE OF THE EXTRUDER, INCREASING THE SCREW ROTATION SPEED, AND PRESENCE OF METHANOL, GEL FRACTION DECREASED. THE RECYCLED XLPE USING ALCOHOL, AT TEMPERATURE OF 240-300OC AND SCREW ROTATION SPEED OF 750 RPM, SHOWED THE MAXIMUM MELT FLOW INDEX.

IN THIS RESEARCH WE DEVELOPED A CONTINUOUS PROCESS FOR RECYCLING OF CROSSLINKED POLYETHYLENE USING CONVENTIONAL EXTRUDERS. THE RECYCLING MECHANISM WAS THERMAL-MECHANICAL-CHEMICAL, AND METHANOL WAS USED AS A RECYCLING AGENT. THE CROSSLINKED POLYETHYLENE WAS PREPARED VIA SILANE GRAFTING- WATER CROSSLINKING METHOD. RHEOLOGICAL PROPERTIES WERE MONITORED AS AN INDICATION OF THE AMOUNT OF DECROSSLINKING. IT WAS FOUND THAT BY SELECTING PROPER PROCESSING CONDITION THE RHEOLOGICAL BEHAVIOR OF DECROSSLINKED PE WILL BE SIMILAR TO THAT OF VIRGIN POLYMER.