Abstract: Apparatuses and methods are disclosed for the production of a polyester/epoxy copolymer that can be applied as a liquid to a surface prior to being cured. The method of preparing the polyester/epoxy copolymer includes mixing maleic acid with dicyclopentadiene to produce a ten-carbon double ring ester, promoting esterification with the addition of a source of hydroxyl, such as an alcohol or a glycol, to a desired acid number and reacting with an epoxy. Optionally, a source of unsaturation may also be added. Examples include excess maleic anhydride, fumaric acid, excess ten carbon ester, nadic anhydride, or tetrahydrophthalic acid. Electrical components of the present invention include a cured coating of the copolymer of the present invention over at least a portion of the component. Specific, selective modifications to 100% reactive polyester/epoxy copolymer electrical varnishes can result in greatly improved moisture and chemical resistance properties.

Abstract: A fully imidized cresylic acid soluble polymer comprising 4,4'- oxydiphthalic anhydride (ODPA), 3,4,3',4',-biphenyltetracarboxylic dianhydride (BPDA), 3,4'-oxydianiline (ODA), and 4,4'-oxydianiline (DAPE) that can be used as a coating material such as a wire coated enamel. The polyimide has relatively low viscosity and high percent solids by substituting some of the 3,4'oxydianiline with 4,4'oxydianiline. Substitution with the 4,4'oxydianiline can be accomplished up to 25% on the molar basis without losing the fully imidized, cresol solubility characteristics.