ABSTRACT
The isobutylene copolymers, of special interest are products with a low amount of diene hydrocarbon — butyl rubbers. To obtain vulcanizing rubbers, various diene monomers can be used, but high quality butyl rubber is obtained only by copolymerization of isobutylene with isoprene. First producers of butyl rubber were the companies Standard Oil of New Jersey and Polymer Corporation Ltd. of Sarnia. Butyl rubber is a product that is amorphous in a wide range of temperatures; crystallization of the polymer proceeds at large elongation. Ability of butyl rubber to crystallize is appreciably determined by the content of isoprene units in the chain. Crystallization of butyl rubber without elongation is possible at double bond content up to 1 mol%. Propensity for crystallization decreases with growth of nonsaturation. Butyl rubber dissolves in saturated hydrocarbons and a little worse in arenes.
