5/5000 Polyvinyl chloride (PVC)
- Dec 22, 2018 -

Basic introduction to


PVC


PVC


Referred to as PVC, thermoplastic resin polymerized by vinyl chloride under the action of 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 amorphous structure of white powder, less branched. The molecular weight of PVC produced by industry is generally within the range of 50,000 ~ 120,000, with greater polydispersity, and the molecular weight increases with the decrease of polymerization temperature. No fixed melting point, 80 ~ 85 ℃ began to soften, 130 ℃ is a viscoelastic state, 160 ~ 180 ℃ began to change for the viscous flow; Has good mechanical properties, tensile strength of about 60MPa, impact strength of 5 ~ 10kJ/m squared; Excellent dielectric properties. But poor stability to heat and light, in more than 100 ℃ or the sun for a long time, will decompose and produce hydrogen chloride, and further automatic catalytic decomposition, cause discoloration, physical and mechanical properties also fell rapidly, must be added in the practical application of stabilizers in order to improve the stability of heat and light. PVC is very hard, solubility is also very poor, can only be dissolved in cyclohexanone, dichloroethane and tetrahydrofuran and other few solvents, organic and inorganic acids, alkali, salt are stable, chemical stability with the increase in the use of temperature and reduce. PVC is dissolved in acetone - carbon disulfide or acetone - benzene mixture solvent, used for dry spinning or wet spinning and fiber, called chloroprene. It is resistant to fire, acid and alkali, microorganism, abrasion and has good heat preservation and elasticity.