ABSTRACT
US Patent 5,350,779 entitled, “Low Exotherm, Low Temperature Curing, Epoxy Impregnants” was filed for on June 29, 1993 and was awarded to Ralph D. Hermansen and Steve Lau on September 27, 1994. For the SAP 391 Electronic Power Conditioner, the current epoxy impregnant must be cured at temperatures of 160°F or higher to achieve an adequate cure. However, residual stresses arise at this cure temperature which can contribute to high-voltage breakdown of the dielectric. A lower curing impregnant could be selected from the data at around 50/50 curative blend composition. The cure temperature could be kept under 130°F and the exotherm of an unattended pint mixture would be far under the decomposition temperature of the material and it would take over 5 h to occur. When the impregnant is cured, the resultant composite has the high mechanical properties of a reinforced plastic.
