Isoolefin-multiolefin copolymers

Claim 1

IN THE PROCESS OF MAKING VULCANIZABLE RUBBERY POLYMERS OF INCREASED TOUGHNESS AND IMPROVED PHYSICAL PROPERTIES, COMPOSED OF A MAJOR PROPORTION OF AN ISOOLEFIN HAVING FROM 4 TO 5 CARBON ATOMS, A MINOR PORPORTION OF A CONJUGATED ALIPHATIC DIOLEFIN OF 4 TO 8 CARBON ATOMS, USING PROPORTIONS TO MAKE A COPOLYMER HAVING AN IODINE NUMBER OF ABOUT 1 TO 50 AND A MINOR PROPORTION OF A DIVINYL AROMATIC COMPOUND, BY POLYMERIZATION AT A TEMPERATURE BELOW -40* C. WITH A FRIEDEL-CRAFTS CATALYST DISSOLVED IN A NON-COMPLEX FORMING SOLVENT WHICH IS LIQUID AT THE POLYMERIZATION TEMPERATURE, THE STEPS IN COMBINATION WHICH COMPRISE USING AN AMOUNT OF SAID DIVINYL AROMATIC COMPOUND OF ABOUT 1% UP TO A MAXIMUM OF ABOUT 4% BY WEIGHT BASED ON ISOBUTYLENE, WHILE ALSO USING A REACTION DILUENT CONTAINING MORE THAN 50% BY VOLUME OF AN ALKYL HALIDE OF 1 TO 2 CARBON ATOMS, AND USING IN EXCESS OF ONE VOLUME OF SAID REACTION DILUENT PER VOLUME OF MIXED OLEFIN REACTANTS, WHEREBY AN INSOLUBLE POLYMER IS OBTAINED.