PROCESS FOR THE PREPARATION OF AN ETHYLENE COPOLYMER IN A TUBULAR REACTOR

摘要

The invention relates to a process a system and a high pressure pump for the preparation of a copolymer of ethylene and a di- or higher functional (meth) acrylate in a tubular reactor, comprising the steps of: injecting ethylene at a pressure of 100 MPa to 350 MPa into the reactor from a high pressure compressor and injecting the (meth)acrylate at a pressure of 100 MPa to 350 MPa into the reactor from a high pressure pump, wherein the high pressure pump comprises - a pump suction chamber for receiving a medium to be compressed; - a cylinder for receiving the medium to be compressed from the pump suction chamber; - an outlet for discharging a compressed medium from the cylinder, - a seal fixed to the inner wall of the cylinder at an end of the cylinder distal to the outlet and - a plunger movable in the cylinder by sliding through the seal, wherein a leakage gap is present along the plunger and the leakage gap is fluidly connected to the pump suction chamber.