The rubber is divided into natural rubber and synthetic rubber. Natural rubber is mainly derived from the Hevea tree, when such a rubber tree skin is a natural latex rubber gloves, neoprene and PVC cut, will outflow milky sap called latex, latex coagulation, washing, molding , dry natural rubber. The synthetic rubber is prepared by synthetic methods, using different raw materials (monomers) can be synthesized by different types of rubber. 1900 ~ 1910 chemist CD Harris (Harris) Determination of the structure of the natural rubber is isoprene polymer, which opens the way for the synthetic rubber. 1910 the Russian chemist SV Lebedev (Lebedev ,1874-1934) to the sodium metal as an initiator, 1,3 - butadiene polymerization Chengding the Buna, later has been found in many new varieties of synthetic rubber, such as cis butadiene rubber, chloroprene rubber, styrene-butadiene rubber, and the like. Synthetic rubber production has greatly exceeded natural rubber, one of the largest production of styrene-butadiene rubber.
General rubber
Refers to a part or all of the types of plastic instead of natural rubber, such as styrene-butadiene rubber, butadiene rubber, isoprene rubber, mainly used in the manufacture of tires and industrial rubber products. Generic rubber demand is the main varieties of synthetic rubber.
Styrene-butadiene rubber
Styrene-butadiene rubber [1] by butadiene and styrene copolymer obtained, the largest output of the generic synthetic rubber, SBR, SSBR and thermoplastic rubber (SBS).
Butadiene rubber
Butadiene was prepared by solution polymerization, butadiene rubber has a particularly excellent cold resistance, abrasion resistance and flexibility, and also has a good anti-aging properties. The butadiene rubber vast majority used in the production of tires, and a small part for the manufacture of cold-resistant products, cushioning material and tape, rubber shoes. The disadvantage of butadiene rubber cross tear resistance, good wet skid resistance.
Isoprene rubber
Referred isoprene rubber polyisoprene rubber, solution polymerization production. Isopentyl rubber and natural rubber, with a good flexibility and abrasion resistance, excellent heat resistance and good chemical stability. Isoprene rubber raw rubber (before processing) and the intensity was significantly lower than that of natural rubber, but uniform quality, processing performance is better than the natural rubber. Isoprene rubber can replace natural rubber can also be used in the production of various rubber products manufacturing truck tires and off-road tires.
Ethylene propylene rubber
Ethylene-propylene rubber as the main raw material for the synthesis of ethylene and propylene, aging resistance, outstanding electrical insulation properties and ozone resistance. Ethylene propylene rubber can be a large number of oil-filled and filling carbon black, lower product prices, ethylene-propylene rubber chemical stability, abrasion resistance, flexibility, oil and styrene butadiene rubber close. A wide range of use of ethylene-propylene rubber, can be used as a tire sidewall, strips and tubes, as well as automobile parts, wires, cable sheath and high pressure, ultra-high pressure insulating material. Rubber products the network also manufacture rubber shoes, hygiene products and other light products.
Neoprene
It chloroprene as a main raw material, and by the homo-or copolymerized in a small amount of other monomers. Such as high tensile strength, heat resistance, light resistance, excellent aging resistance, oil resistance than natural rubber, styrene-butadiene rubber, polybutadiene rubber. Has a strong flame resistance and excellent resistance to extension incombustibility, its high chemical stability, good water resistance. Neoprene rubber network drawback is that the electrical insulation properties, cold can be poor, the instability of the raw rubber during storage. Neoprene wide range of uses, such as transport belts and transmission belts, wires, cables foreskin material used to produce, manufacture oil hose, gaskets, equipment and chemical resistant lining.
Linear structure: general structure of the unvulcanized rubber. Due to the large molecular weight, no external force was fine the slug. When the external force, the removal of the external force, the degree of entanglement of the fine group changes, molecules the chain rebound, resulting in the strong tendency of recovery, which is the origin of the rubber highly elastic.
Branched structure: rubber macromolecules branched chain aggregation, the formation of gel. Gel properties and processing of rubber are unfavorable. In the rubber mixing, the various compounding agents often progress gel region, forming a local blank, forming reinforcement and crosslinking can not become the weak parts of the product. Crosslinked structure: linear molecule through a bridging atom or atomic group are connected to each other together to form a three-dimensional mesh structure. Carried out as the vulcanized course, this structure is constantly strengthened. Thus, the ability of the free activity of segment decreased plasticity and elongation decreased, increased strength, elasticity and hardness, compression permanent deformation and the degree of swelling decreased.