Fibre containing polymers and process for production thereof

Vulcanizates produced by the steps comprising mixing a mixture of polymer and fibrous material with rubber compounding ingredients and vulcanization active agents, shaping the so-formed mixture and vulcanizing the shaped mixture by heating at an elevated temperature, wherein said mixture of polymer and fibrous material is produced by the process comprising the steps of providing an agitated aqueous solution of coagulant for the polymer, said coagulant being selected from the group consisting of calcium chloride, sulphuric acid plus sodium chloride, sulphuric acid plus sodium chloride plus polyamine compound, alum, and alum plus sulphuric acid, adding an aqueous suspension of said fibrous material to the coagulant solution, adding said polymer in aqueous latex form to said coagulant solution and co-coagulating said polymer and fibrous material, and recovering and drying the mixture of polymer and fibrous material, said fibrous material being a polymeric paraphenylene terephthalamide aramid having an average length of from about 1 to about 5 mm and a BET surface area of greater than 1 m.sup.2 /g.