Rubber-sulphur reaction bonding process

When isoprene and similar hydrocarbons polymerize only a part of the double bonds present are involved in the union of the several molecules the rubber formed as a result is unsaturated. It shows the reactions characteristic of the derivatives of ethylene. Owing to this unsaturation it will add sulphur. This process, which is called vulcanization, was discovered by Goodyear in 1839. Vulcanization is usually effected by heating the mixture of rubber and sulphur at about 140°. Sheet rubber can be vulcanized in the cold by dipping it into a dilute solution of sulphur monochloride in a volatile solvent, such as carbon disulphide or benzene. 

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