DAMPING MATERIAL COMPOSITIONS AND DAMPING MATERIALS.

摘要

The liq. polymer (c-1) contains on ave. per mol. 1.6 or more units of at least one functional gp. that can react with the epoxy gps. the epoxy resin. These gps. are selected from among carbonyl, acid anhydride, amide, and mercapto gps. The glass transition pt. (c-1) is specified to be 0 deg.C or less. The curing agent (b) can be an amine, an acid anhydride, a polyamide or a dicyandiamide. (c-1) is specified to be an ethylene-alpha-olefin copolymer grafted with maleic acid anhydride. Another type of damping material compsn. comprises an epoxy resin of polyglycidyl ether (a-2) with a polyol or its polymer (a-2), a curing agent (b), and an aromatic hydrocabron (c-2) such as a phenol or a polymer contg. at least one of these as main component. The softening pt. of (c-2) is 25 deg.C or lower. Another type of amping material composition comprises (I) an epoxy resin and (b) a curing agent. The equiv. ratio (b) to (I) lies between 0.6 and 1.4. The epoxy resin (I) is obtd. by adding a cyclic ester (c-3) to a bisphenol type epoxy (a-3), with the wt. ratio (c-3)/(a-3)=20/80 to 98/2. The damping materials are obtd. by the curing reaction of the above mentioned epoxy resin with the curing agent.