Effectiveness of Organic Peroxide Initiators in the High-Pressure Polymerization of Ethylene

Abstract

Abstract The effectiveness of organic peroxides as initiators in the polymerization of high-pressure polyethylene has been studied in order to assess the most successful from a technical and economic view point. For this purpose polymerization experiments were carried out with ten different peroxides which are effective at various temperature ranges, e.g., 110 to more than 300° C. The organic peroxide consumption per kilogram of polyethylene produced was determined as a function of reaction temperature, pressure, organic peroxide concentration, and the mean residence time in the reactor. Also the dependence on the intensity of stirring inside the reactor was studied. The organic peroxide consumption initially decreases with increasing temperature, passes through a minimum, and then rises again. The minimum organic peroxide consumption and the related temperature are different for individual organic peroxides and are greatly influenced by the reaction conditions. From a study of the results, criteria to se...