Polyvinylchloride(PVC)

PVC is a thermoplastic resin polymerized by vinyl chloride under the action of an initiator. It's a homopolymer of vinyl chloride. Vinyl chloride homopolymer and vinyl chloride copolymer are collectively referred to as vinyl chloride resin. PVC is white powder with amorphous structure and small branching degree. The molecular weight of industrial PVC is generally in the range of 50,000 ~ 120,000, with large polydispersity, molecular weight increases with the decrease of polymerization temperature; There is no fixed melting point, the melting begins to soften at 80 ~ 85℃, becomes viscoelastic at 130℃, and becomes viscoelastic at 160 ~ 180℃. Has good mechanical properties, tensile strength about 60MPa, impact strength 5 ~ 10kJ/m²; It has excellent dielectric properties. However, the stability of light and heat is poor, at 100℃ or after a long time of sunlight exposure, it will decompose and produce hydrogen chloride, and further automatic catalytic decomposition, cause discoloration, physical and mechanical properties are also rapidly decreased, in practical applications must be added stabilizer to improve the stability of heat and light. PVC is very hard, solubility is also very poor, can only dissolve in cyclohexanone, dichloroethane and tetrahydrofuran and other a few solvents, organic and inorganic acids, bases, salts are stable, chemical stability decreases with the use of temperature. PVC is dissolved in acetone - carbon disulfide or acetone - benzene mixed solvent, used for dry spinning or wet spinning and fiber, called chlorlon. It is inflammable, resistant to acid and alkali, anti-microbial, wear-resisting and has good heat preservation and elasticity.