Polyvinyl chloride, abbreviated as PVC (Polyvinyl Chloride) in English, is a vinyl chloride monomer (VCM) in peroxides, azo compounds and other initiators; or under the action of light and heat according to the free radical polymerization reaction mechanism Polymers formed by polymerization. Vinyl chloride homopolymer and vinyl chloride copolymer are collectively referred to as vinyl chloride resin. PVC is the world's third-most widely produced synthetic plastic polymer. It comes in two basic forms: rigid (sometimes abbreviated as RPVC) and flexible. The rigid form of PVC is used in construction for pipe and in profile applications such as doors and windows. It is also used in making plastic bottles, non-food packaging, food-covering sheets and plastic cards (such as bank or membership cards). It can be made softer and more flexible by the addition of plasticizers, the most widely used being phthalates. In this form, it is also used in plumbing, electrical cable insulation, imitation leather, flooring, signage, phonograph records, inflatable products, and many applications where it replaces rubber. With cotton or linen, it is used in the production of canvas. Pure polyvinyl chloride is a white, brittle solid. It is insoluble in alcohol.It is a more flexible and more easily processed material that soon achieved widespread commercial use.