PVC plastic raw material
The color is slightly yellow translucent and shiny. The transparency is better than that of polyethylene and polypropylene, and worse than that of polystyrene. It is divided into soft and rigid chloroethylene , and the soft products are soft and tough, and the stickyis higher than that of the low density polyethylene. Less than polypropylene, whitening occurs at the inflection point. Stable; not easy to be acid, alkali corrosion; more tolerant to heat.
Polyvinyl chloride has a flame retardant (flame retardant value of 40 or more), high chemical resistance (concentrated hydrochloric acid, sulfuric acid with a concentration of 90%, nitric acid with a concentration of 60%, and sodium hydroxide with a concentration of 20%), mechanical strength And good electrical insulation.
Polyvinyl chloride is less stable to light and heat. The softening point is 80°C and decomposition begins at 130°C. Without heating stabilizers, polyvinyl chloride begins to decompose at 100°C and decomposes faster at temperatures above 130°C. Heated to decompose and release hydrogen chloride gas (hydrogen chloride gas is a toxic gas) to make it change from white to light yellow to red to brown to black. The ultraviolet and oxygen in the sun will cause the photo-oxidative decomposition of polyvinyl chloride, thus reducing the flexibility of polyvinyl chloride and eventually becoming brittle. It is not difficult to understand why some PVC plastics will turn yellow and become brittle after a long time.
Has a stable physical and chemical properties, insoluble in water, alcohol, gasoline, gas, water vapor leakage; at room temperature can withstand any concentration of hydrochloric acid, 90% of the following sulfuric acid, 50-60% of nitric acid and 20% of the following Caustic soda solution has certain chemical resistance; it is quite stable to salts, but it can be dissolved in organic solvents such as ethers, ketones, chlorinated aliphatic hydrocarbons and aromatic hydrocarbons. PVC pellets
HPVC/SBR thermoplastic elastomer
Industrial polyvinyl chloride resin is mainly amorphous structure, but also contains some crystalline regions (about 5%), so PVC does not have a significant melting point, began to soften at about 80 °C, heat distortion temperature (1.82MPa load) for At 70-71°C, the flow starts at 150°C under pressure, and hydrogen chloride begins to evolve slowly, causing the polyvinyl chloride to change color (from yellow to red, brown, and even black).PVC pellets
The weight average molecular weight of industrial polyvinyl chloride is in the range of 4.8-4.8 million, and the corresponding number average molecular weight is 2-1.95 million. The vast majority of industrial resins have a weight average molecular weight of 10-20 million and a number average molecular weight of 4.55-64 million. Hard PVC (without plasticizer) has good mechanical strength, weather resistance and flame resistance, and can be used alone as a structural material, used in the manufacture of pipes, plates and injection-molded products in the chemical industry. Rigid polyvinyl chloride can use reinforcing materials.PVC pellets