Poly(vinyl chloride) on the Way from the 19th Century to the 21st Century*
نویسنده
چکیده
Despite all the technical and economic problems and the public discussions on the environmental dangers and hazards of chlorine chemistry, poly(vinyl chloride) (PVC) is the second most produced plastic (with a worldwide capacity of about 31 million tons), placing after polyolefins and before styrene polymers. Presently, PVC production worldwide is growing at a rate of more than 4% per year. The application of PVC was first described in a patent in 1913, but only after 1930 did a sustained interest in PVC arise in several industrial laboratories. The most remarkable milestones in PVC history and their importance to the development of macromolecular chemistry are briefly described, and some present PVC research and industrial applications, with respect to polymerization, stabilization, bulk property modification, and chemical and material recycling of PVC waste, are discussed. Some actual selected topics include the emulsion polymerization of vinyl chloride with polymeric surfactants and controlled free-radical polymerization with nitroxyls, whereas ionic and metal organic initiators have not found any technical applications. Chemical reactions offer many possibilities for the modification of PVC, but they have been not used on a technical scale yet. Much work has been done on stabilization with nontoxic or metal-free systems. The bulk properties of PVC can be influenced by impact modification through the addition of graft copolymers or by blending with other polymers. Also presented are some problems and recent developments in PVC recycling. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 578–586, 2004
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