![]() ![]() VCM and water are introduced into the reactor along with a polymerization initiator and other additives. Suspension polymerization affords particles with average diameters of 100–180 μm, whereas emulsion polymerization gives much smaller particles of average size around 0.2 μm. Emulsion polymerization accounts for about 12%, and bulk polymerization accounts for 8%. Ībout 80% of production involves suspension polymerization. Polyvinyl chloride is produced by polymerization of the vinyl chloride monomer (VCM), as shown. Goodrich Company developed a method in 1926 to plasticize PVC by blending it with various additives, including the use of dibutyl phthalate by 1933. In the early 20th century, the Russian chemist Ivan Ostromislensky and Fritz Klatte of the German chemical company Griesheim-Elektron both attempted to use PVC in commercial products, but difficulties in processing the rigid, sometimes brittle polymer thwarted their efforts. The polymer appeared as a white solid inside a flask of vinyl chloride that had been left on a shelf sheltered from sunlight for four weeks. PVC was synthesized in 1872 by German chemist Eugen Baumann after extended investigation and experimentation. It is insoluble in alcohol but slightly soluble in tetrahydrofuran. Pure polyvinyl chloride is a white, brittle solid. With cotton or linen, it is used in the production of canvas. It is used in plumbing, electrical cable insulation, flooring, signage, phonograph records, inflatable products, and in rubber substitutes. Adding plasticizers makes PVC softer and more flexible. ![]() It is also used in making plastic bottles, packaging, and bank or membership cards. Rigid PVC is used in construction for pipe, doors and windows. PVC comes in rigid (sometimes abbreviated as RPVC) and flexible forms. About 40 million tons of PVC are produced each year. Polyvinyl chloride (alternatively: poly(vinyl chloride), colloquial: polyvinyl, or simply vinyl abbreviated: PVC) is the world's third-most widely produced synthetic polymer of plastic (after polyethylene and polypropylene). ![]()
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