Epoxidized polyene, epoxy resin composition and product of curing thereof, and powder coating material

TLDR: In this article, an epoxidized polyene having either epoxy groups alone or both epoxy and hydroxyl groups was presented. But the authors did not specify the type of epoxy group.

Abstract: The first invention relates to an epoxidized polyene having either epoxy groups alone or both epoxy groups and hydroxyl groups, characterized in that in the 1 H-NMR spectrum, the sum of integrated values of signals within the range of 1-6 ppm that are assignable to hydrogen atoms on the carbon atoms to which epoxy groups or hydroxyl groups are bonded accounts for 15.5-20.0% of the total integrated value of all the proton signals. The epoxidized polyene of the invention has excellent compatibility with epoxy resins by virture of the presence of a specific amount of epoxy groups or a combination of epoxy and hydroxyl groups. The second invention relates to an epoxy resin composition characterized by containing a mixture of 20-60% by weight of an epoxidized polyene which has an oxirane oxygen content of 6.5-13% by weight and which is prepared by epoxidizing a liquid poly-1,3-diene in which double bonds resulting from 1,4-linkages account for at least 50% of all double bonds and which liquid poly-1,3-diene has a number-average molecular weight of 1,000-30,000 and 80-40% by weight of an epoxy resin other than epoxidized polyenes (the total amount of both being 100% by weight) and a phenol resin which serves as a curing agent. According to the invention, through incorporation of a specific epoxidized polyene, a bisphenol-type epoxy resin, and a curing agent into the composition, a coating film having excellent impact resistance and bend resistance can be formed on metallic surfaces, etc. The third invention relates to a composition comprising diepoxidized dicyclopentadiene and a compound having two or more carboxyl groups in the molecule. This compound has excellent chemical resistance, corrosion resistance, heat resistance, and weather resistance, as well as remarkable gloss, etc.; is useful in the production of powder coating materials; and does not irritate the skin during use.