Polyvinyl chloride(cas:93050-82-9)

Polyvinyl chloride, abbreviated as PVC, is one of the earliest plastics to be industrialized; its current production volume ranks second only to polyethylene. PVC finds extensive application in industry, agriculture, and daily life. It is a polymer compound formed by the polymerization of vinyl chloride. It is a thermoplastic material appearing as a white or pale yellow powder. It has a relative density of 1.35–1.40, a chlorine content of 56%–58%, and a melting point of approximately 70–85°C. It is soluble in—or swells in the presence of—ketones, esters, tetrahydrofuran, and chlorinated hydrocarbons. It exhibits excellent chemical corrosion resistance. However, its thermal stability and light resistance are relatively poor; it begins to decompose and release hydrogen chloride at temperatures above 100°C or upon prolonged exposure to sunlight, so stabilizers must be added during plastic manufacturing. It possesses excellent electrical insulation properties and is non-flammable. It is used to manufacture plastics, coatings, and synthetic fibers. Depending on the amount of plasticizer added, it can be processed into either flexible or rigid plastics. The former is used for transparent films (such as raincoats, tablecloths, packaging materials, and agricultural films), artificial leather, foam plastics, and wire insulation/sheathing. The latter is used for sheets, pipes, valves, doors, and windows. Suspension polymerization yields a powdered resin, while emulsion polymerization yields a paste resin; both types can be used to produce flexible or rigid plastics.