Isulated electrical products and processes of forming such products

Abstract

High temperature insulated electrical wiring products suitable for use under service temperature classifications of at least 90.degree. C. The product comprises an electrical conductor and a polyvinyl chloride insulation covering on the conductor. The insulation comprises polyvinyl chloride resin having an inherent viscosity within the range of 1.0-1.1 and a polybasic aromatic ester plasticizing system in which the predominant ester component is a dialkyl phthalate ester. Each of the alkyl groups of the ester contains at least 11 carbon atoms. In addition, the insulation contains a higher than normal amount of antioxidant. The insulation should contain at least about 1.5 percent bisphenol A based upon the dialkyl phthalate ester. The plasticizer system may contain only dialkyl phthalate ester or it may contain minor amounts of trimellitate ester. Also disclosed is a production process for electrical wiring products in which a hot melt of PVC insulation formulation as described above is extruded onto an electrical conductor and the conductor then cooled to form the insulated wiring product. The extrusion procedure may be carried out at lower than normal temperature and higher than normal extrusion rates.