Abstract: A new rubber composition, the vulcanizate of which has reduced permeability to gases, comprises: one hundred parts by weight of at least one butyl-type rubbery polymer; from about 3 to about 20 parts by weight of .alpha.-methylstyrene homopolymer having a softening point of from about 93.degree. C. to about 150.degree. C. and a Tg of from about 15.degree. C. to about 75.degree. C.; from about 30 to about 90 parts by weight of at least one carbon black, from 0 to about 7 parts by weight of hydrocarbon extender oil; and a curing system. A process for producing said rubber composition is also provided.

Abstract: There is provided a tubeless pneumatic tire with an inner liner having puncture sealing characteristics comprising as the inner liner a puncture sealing laminate having an outer halobutyl polymer containing layer and an inner polymer containing layer, the inner layer of the laminate having been reacted with a zinc peroxide compound.

Abstract: Elastomeric compositions containing EPDM elastomers are provided, the vulcanizates of which show substantially improved adhesion properties with good dynamic ozone resistance, superior aged fatigue life and high resilience. The EPDM used is of high molecular weight and has a non-conjugated diene content of at least 6 weight percent preferably at least 7.5%. The composition also contains highly unsaturated elastomers, such as natural rubber and polybutadiene, as the additional elastomeric components.