Abstract: A crosslink curable ethylene-propylene rubber composition with improved resistance to heat, the cured rubber composition and electrical conductors insulated with said cured rubber composition. The improved rubber composition comprises a combination of ethylene-propylene rubber, chlorosulfonated polyethylene, zinc oxide, talc and carbon black in particular proportions.

Abstract: The mending of defective semiconductive components of insulated electrical cable, comprising filling and sealing voids or breaks within a body of semiconductive material with a curable semiconductive patching compound comprising the combination of chlorosulfonated polyethylene, conductive filler and lauroyl peroxide, and heating the patching compound to cure the same.

Abstract: A composite of polymeric materials which are adheringly joined to each other and which can be easily and cleanly separated by stripping apart with a low pulling force whereupon the contacting surfaces of their interface separate cleanly without retention of any residue on one from the other, and which comprises the combination of a previously cured body of a copolymer of ethylene and propylene adjoined to a subsequently cured body of an elastomeric blend of a copolymer of ethylene and propylene admixed with chlorosulfonated polyethylene. The combination of materials is especially advantageous when used in electrically conducting wire and cable constructions as a composite of an electrical insulation and an overlying strippable semiconductive layer.

Abstract: The provision of a durable, slick sliding surface on metal faces of plastic forming extrusion apparatus such as extruder nozzles and dies. The durable, slick sliding metal surface is provided by burnishing and heat treating a polysiloxane fluid on the face of the metal. The burnishing comprises vigorous rubbing of the polysiloxane fluid treated metal face with a material relatively softer than the metal face being treated, effectively over the entire surface treated.