| The PVC resin is one of five kinds of generally synthesized resins, and its yield is only next to PE. Many kinds of materials, such as architectural materials, wrapper, electronical materials, commodities, etc., can be manufactured by the PVC resin due to its excellent characteristics of chemical anticorrosion, electronical insulation, chemical stability, thermoplastic, reduced cost, easy processing. The PVC resin has been widely applied to the fields of industry, agriculture, architecture, transportation, electron and packing.There are 4 methods of synthesizing PVC resin in the industry, such as suspension polymerization, bulk polymerization, emulsion polymerization and solution polymerization. The PVC resin synthesized by suspension polymerization occupancies 80% of all PVC resins. The initiator system is very important in the suspension polymerization of vinyl chloride. Choice and dosage of initiators are very important factors, which can influence polymerization rate, capability in adhibiting reactor, quality and structure of the PVC polymer. The initiator can also influence the combined way of vinyl chloride (VC) monomer (VCM) in the PVC chains.In this paper, the models of initiator decomposing and polymerization kinetics were established on basis of the application study of composite initiator system in the suspension polymerization of VC. Heat transfer rate of the reactor was also studied. The different initiator systems, which used to synthesize different kinds of PVC resins, were designed on basis of the tests of single initiator and kinetic studies of initiator decomposing and polymerization of VC. The These initiator systems were applied to the tests in 4 m~3 reactor and 135 m~3 reactor, respectively. It is found that the polymerization rates could remain constant, the polymerization time could be decreased, the production quality could be controlled, and that the production ability of reactors could be increased.
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