History of rubber discovery and utilization

The word rubber comes from the Indian cau-uchihu, which means "weeping tree". Natural rubber is formed by condensation and drying of latex of rubber tree with three leaves. 1770, British chemist J. priestley discovered that rubber can be used to erase pencil handwriting. At that time, the material used for this purpose was called rubber, which has been used ever since. The molecular chain of rubber can be crosslinked, and the crosslinked rubber has the ability of rapid recovery when deformed by external force, and has good physical and mechanical properties and chemical stability. Rubber is the basic raw material of rubber industry, which is widely used to manufacture rubber products such as tires, hoses, tapes and cables.

Rubber is divided into natural rubber and synthetic rubber. Natural rubber mainly comes from rubber tree with three leaves. After the epidermis of this rubber tree is cut, milky white juice will flow out. This juice is called latex. Natural rubber is obtained by coagulation, washing, molding and drying. Synthetic rubber is artificially synthesized, and different kinds of rubber can be synthesized by using different raw materials (monomers). From 1900 to 19 10, chemist C. D. Harris determined that the structure of natural rubber was a high polymer of isoprene, which opened a way for synthetic rubber. 19 10 years, Russian chemist Lebedev (1874- 1934) polymerized 1 3- butadiene into sodium butadiene rubber, cis-1,4-polybutadiene rubber, chloroprene rubber and many others. The output of synthetic rubber has greatly exceeded that of natural rubber, and the largest output is styrene-butadiene rubber.