Tailoring glycidyl ester resin systems for electrical insulator requirements

Saturated CyGEs resins cured with hexahydrophthalic anhydride in the stoichiometric combining ratio of 1-1 expoxide:anhydride groups provide outstanding tracking resistance and weatherability. Polymeric CyGEs resins (semi-solid and hard resin versions) impart good thermal shock resistance to filled encapsulating compounds while retaining the excellent tracking resistance and weatherability of the liquid glycidyl esters. Polymeric CyGEs hard resins can be formulated into non-tracking molding compounds capable of producing finished parts on 3-minute press cycles. Variations in filler types and combinations, including incorporation of fibrous reinforcements, should be explored to optimize these molding compounds. Performance tests conducted on molded transformer bushings, standoff insulators and other finished parts will be required to better assess this CyGE´s molding approach to replacing ceramic insulation