Isobutylene-Containing Compositions and Articles Made Thereof

An elastomer composition can comprise a Cto Cisoolefin; a non-halogenated alkylstyrene; a halogenated alkylstyrene; and optionally a diolefin, wherein the Cto Cisoolefin is not the same as the diolefin. Optionally, the elastomer composition can be blended with a butyl rubber and/or a halobutyl rubber. Such blends that also comprise additives may be suitable for producing tire components such as innerliners.