Processable rubber compositions comprising a vulcanized elastomer dispersed in a matrix of a thermoplastic polymeric material. In one embodiment the matrix forms a continuous phase and the vulcanized elastomeric material is in the form of particles forming a non-continuous phase. The compositions are made by combining a curative, an uncured fluorocarbon elastomer, and a reactive oligomer, and heating the mixture at a temperature and for a time sufficient to effect vulcanization of the elastomeric material and polymerization of the oligomer, while mechanical energy is applied to mix the mixture during the heating step. Shaped articles such as seals, gaskets, O-rings, and hoses may be readily formed from the rubber compositions according to conventional thermoplastic processes such as blow molding, injection molding, and extrusion.

Methods for making processable rubber compositions containing fluorocarbon elastomers cured by polyol or phenol curative agents include an optional heat treating step before thermoplastic processing. In one aspect, a dynamic vulcanizate of a fluorocarbon elastomer containing an excess of un-reacted polyol curative agent is subject to a pre-molding heat treatment at a temperature of 150.degree. C. or above, but preferably below the thermoplastic processing temperature, for a time sufficient to drive off or decompose at least part of the un-reacted or excess polyol curative agent. After part or all of the curative agent is driven off or decomposed by the heat treatment, the heat treated material may be thereafter processed by thermoplastic techniques to form shaped articles. Advantageously, articles produced by thermoplastic processing of the heat treated dynamic vulcanizates are characterized by a low permeability to gases and vapors.

A method of sealing an interface, the method comprising: providing a sealant material, locating the sealant material adjacent to the interface, exposing the sealant material to an elevated temperature such that the sealant material flows adjacent the interface, and curing the sealant material to seal the interface.

An activatable material and articles incorporating the same is disclosed. The activatable material includes at least three of an epoxy resin; a thermoplastic polyether; a blowing agent; a curing agent; and a filler. The activatable material is preferably used for sealing, baffling or reinforcing an article of manufacture such as an automotive vehicle.

An expandable material and articles incorporating the same are disclosed. The material includes a polymeric admixture; a blowing agent; a curing agent; a tackifier; and optionally, a filler or fiber.