General-purpose rubber and specialty rubber

The comprehensive performance of general-purpose rubber is good, and it is widely used, mainly including:
1. Natural rubber. It is made from the latex of Hevea brasiliensis with cis-polyisoprene as its basic chemical composition. Good elasticity, high strength, and good overall performance.
2. Isoprene rubber. The full name is cis-1,4-polyisoprene rubber, which is a high cis synthetic rubber made from isoprene. Due to its similar structure and properties to natural rubber, it is also known as synthetic natural rubber.
3. Styrene-butadiene. SBR, abbreviated as SBR, is obtained by copolymerization of butadiene and styrene. According to the production method, it can be divided into lotion polymerized Styrene-butadiene and solution polymerized Styrene-butadiene. Its comprehensive performance and chemical stability are good.
4. Polybutadiene. The full name is cis-1,4-polybutadiene rubber, abbreviated as BR, obtained by polymerization of butadiene. Compared with other general-purpose rubbers, vulcanized Polybutadiene has excellent cold resistance, abrasion resistance and elasticity, less heat under dynamic load, good aging resistance, and is easy to use with natural rubber, Neoprene, Nitrile rubber, etc.
Special type rubber refers to rubber with certain special properties, mainly including:
1. Neoprene. It is called CR for short, and is prepared by polymerization of Chloroprene. It has good comprehensive performance, including oil resistance, flame resistance, oxidation resistance, and ozone resistance. But its density is relatively high, it is prone to crystallization and hardening at room temperature, has poor storage performance, and poor cold resistance.
2. Nitrile rubber. NBR, abbreviated as NBR, is obtained by copolymerization of butadiene and acrylonitrile. Good oil and aging resistance, suitable for long-term use in air at 120 ℃ or oil at 150 ℃. In addition, it also has water resistance, air tightness, and excellent bonding performance.
3. Silicone rubber. The main chain is composed of alternating silicon and oxygen atoms, with organic groups on the silicon atoms. High and low temperature resistance, ozone resistance, and good electrical insulation.
4. Fluorine rubber. Synthetic rubber containing fluorine atoms in its molecular structure. It is usually expressed by the number of fluorine atoms of fluorine containing units in the copolymer, such as fluororubber 23, which is a copolymer of vinylidene fluoride and Chlorotrifluoroethylene. Fluorine rubber is resistant to high temperature, oil, and chemical corrosion.
5. Polysulfide rubber. It is formed by condensation of dihaloalkanes and Polysulfide of alkali metals or alkaline earth metals. It has excellent oil resistance and solvent resistance, but its strength is not high, its aging resistance and processability are not good, and it has bad smell. It is mostly used together with Nitrile rubber. In addition, there are polyurethane rubber, chlorohydrin rubber, acrylic rubber, etc.