PROCESS FOR PRODUCING PELLETS OF COPOLYMERS OF PROPYLENE

摘要

The present invention provides a process for extruding and pelletising a propylene copolymer. The copolymer has a content of comonomer from 5 to 40% by mole, a melt flow rate MFR2 measured at 230 °C under a load of 2.16 kg of from 0.5 to 15 g/10 min and a content of cold xylene soluble material of from 20 to 60% by weight. The process comprises extruding the propylene copolymer through a die plate into an underwater pelletiser and cutting strands of the propylene copolymer into pellets in the underwater pelletiser, wherein the ratio of the mass flow rate of the propylene copolymer to the mass flow rate of the cooling water is from 0.020 to 0.060; and the propylene copolymer comprises a polymeric nucleating agent.