FREE-RADICAL GRAFTING OF DIETHYLMALEATE ON LINEAR LOW-DENSITY POLYETHYLENES

Grafting of preformed polymers is an important method for preparing po lymers with functional groups. Lately, the use of extruders as polymer ization reactors has increased considerably in industry. However, the knowledge of the total reaction process is still limited. Grafting of diethylmaleate on linear low-density polyethylenes (LLDPEs) was carrie d out in solution and in a corotating twin screw extruder. The effects of initiator and diethylmaleate concentrations, temperature, and reac tion time on graft content and on crosslinking were investigated. The functionalization reaction was also conducted in the presence of an el ectron donor material to minimize the amount of crosslinked products i n the extruder. The grafted products were characterized by means of FT IR and the thermal behavior of LLDPEs and that of its grafted products was determined.