The natural color of polyvinyl chloride is yellowish translucent and shiny. Transparency is better than polyethylene, polypropylene, and is different from polystyrene. It is divided into soft and hard polyvinyl chloride according to the amount of additives. The soft products are soft and tough, and the hand feels sticky. The hardness of hard products is higher than that of low density polyethylene. Below polypropylene, whitening occurs at the bend. Stable; not easily corroded by acid or alkali; more resistant to heat.
Polyvinyl chloride has flame retardancy (flame retardancy value of 40 or more), high chemical resistance (concentrated hydrochloric acid, 90% sulfuric acid, 60% nitric acid and 20% sodium hydroxide), mechanical strength And the advantages of good electrical insulation.
It has stable physicochemical properties, is insoluble in water, alcohol, gasoline, and has low gas and water vapor leakage. It can withstand any concentration of hydrochloric acid, 90% or less sulfuric acid, 50-60% nitric acid and 20% or less at normal temperature. The caustic soda solution has certain chemical resistance; it is quite stable to salts, but can be dissolved in organic solvents such as ethers, ketones, chlorinated aliphatic hydrocarbons and aromatic hydrocarbons.