Abstract: Elastomeric polymers and compounded elastomers having reduced amounts of leachables and improved resistance to ?-irradiation sterilization suitable for pharmaceutical stopper and seal applications. These polymers and compounded elastomers maintain their physical performances upon being exposed to ?-irradiation over time and typical use conditions. The polymer is prepared by reacting a mixture of i) a C4 to C7 isoolefin monomer, ii) a styrene based monomer, and optionally iii) a C4 to C14 multiolefin monomer wherein the polymer contains 5 to 15 wt % of styrene derived units.

Abstract: Elastomeric polymers and compounded elastomers have reduced amounts of leachables. The compound comprises a polymer and 50 to 100 phr of filler. The polymer is prepared by reacting a mixture of i) a C4 to C7 isoolefin monomer, ii) a styrene based monomer, and optionally iii) a C4 to C14 multiolefin monomer wherein the polymer contains 5 to 15 wt % of styrene derived units. At least 5% of the filler is precipitated silica.

Abstract: Elastomeric polymers and compounded elastomers having reduced amounts of leachables and improved resistance to ?-irradiation sterilization suitable for pharmaceutical stopper and seal applications. These polymers and compounded elastomers maintain their physical performances upon being exposed to ?-irradiation over time and typical use conditions. The polymer is prepared by reacting a mixture of i) a C4 to C7 isoolefin monomer, ii) a styrene based monomer, and optionally iii) a C4 to C14 multiolefin monomer wherein the polymer contains 5 to 15 wt % of styrene derived units.

Abstract: Elastomeric polymers and compounded elastomers have reduced amounts of leachables. The compound comprises a polymer and 50 to 100 phr of filler. The polymer is prepared by reacting a mixture of i) a C4 to C7 isoolefin monomer, ii) a styrene based monomer, and optionally iii) a C4 to C14 multiolefin monomer wherein the polymer contains 5 to 15 wt % of styrene derived units. At least 5% of the filler is precipitated silica.

Abstract: Transparent and colorable elastomeric compositions are provided. The transparent elastomeric compositions can be covulcanized with rubbers such as polybutadiene, polyisoprene, styrene-butadiene rubber, styrene-isoprene-butadiene rubber, isoprene-butadiene rubber, ethylene-propylene diene rubber or natural rubber. The colorable rubber compositions have sufficient properties to function as a reinforcing member in an automobile tire. Preferably, both the transparent and colorable elastomeric compositions include at least one copolymer of a C4 to C7 isoolefin and a para-alkylstyrene, silica and a coupling agent.