A halogenated elastomer partially functionalized with triethylamine, in a mixture with fiiier and a cure package, suitable for use as an air barrier in an innertube or tire innerliner, is disclosed. The halogenated elastomer can be a polymer comprising C4 to C7 isoolefm derived units, para-alkylstyrene derived units, para-(haloalkylstyrene) derived units, and para-(triethylammoniumalkylstyrene) derived units. The Mooney viscosity of the elastomer can be controlled by the degree of triethylamine functionalization. Also disclosed is a method for making an article using the tri ethy iamine-functionalized elastomer.