The invention is directed to a toughener for epoxy adhesives, the toughener being a reaction product of a bisphenolic blocked PU toughener with a diglycidyl ether-bisphenol product such as liquid DGEBA. The invention includes adhesives comprising the inventive tougheners, methods of using the tougheners and adhesives comprising them, as well as cured inventive adhesives and products comprising them.

The present invention has an object of obtaining an electrically peelable adhesive product that is strong in adhesibility when used, is excellent in peelability even though a low voltage is applied, and does not leave much adhesive deposit after being peeled. The present invention achieves the above object by virtue of an electrically peelable adhesive composition contained in the adhesive product, the adhesive composition comprising an acrylic polymer, an ionic liquid having an ionic conductivity of 10.sup.−4 S/cm or more to 10.sup.−2 S/cm or less, and an alkyl ether of a polyethylene glycol, and containing 5 parts by weight or more to 30 parts by weight or less of the ionic liquid and of the alkyl ether of the polyethylene glycol with respect to 100 parts by weight of the acrylic polymer.

An optically transparent adhesive resin composition includes an ester polymer which contains an ester bond within a repeating unit, a (meth)acrylic ester polymer which contains a (meth)acrylic ester bond within the repeating unit, a rubber polymer, and a crystalline polymer.

An optically transparent adhesive resin composition includes an ester polymer which contains an ester bond within a repeating unit, a (meth)acrylic ester polymer which contains a (meth)acrylic ester bond within the repeating unit, a rubber polymer, and a crystalline polymer.

A polymer having a hydrophobic polymer chain derived from monomers of farnesene and other optional monomers, such as dienes and vinyl aromatics. The polymer also includes one or more terminal functional groups, such as an amino group, a glycidyl group, a carboxylic acid group, a (meth)acrylate group, a silane group, an isocyanate group, an acetoacetate group, a phenolic group, and a hydroxyl group. Functional groups, such as carboxylic acids, may also be grafted along the hydrophobic polymer chain. The polymer may be incorporated in curable compositions that optionally include one or more polymer resins having similar functional groups. Methods for preparing the curable polymer compositions are also provided. The curable or cured form of the polymer composition may be used in various products, such as a sealant, a coating, a caulk, an electric potting compound, a membrane, a sponge, a foam, an adhesive, or a propellant binder.

Two-part silane modified polymer/free radically curable adhesive systems demonstrating improved strength and percent elongation are provided.

Two-part silane modified polymer/free radically curable adhesive systems demonstrating improved strength and percent elongation are provided.

The pressure sensitive adhesive sheet is a sheet shaped pressure sensitive adhesive including an acryl-based base polymer. The acryl-based base polymer contains an acryl-based segment and a urethane-based segment, and a content of the urethane-based segment is 3 to 30 parts by weight based on 100 parts by weight of the acryl-based segment. The urethane-based segment includes at least one urethane chain selected from the group consisting of a polyether urethane and a polyester urethane. The content of the urethane-based segment other than the polyether urethane-based segment is 15 parts by weight or less based on 100 parts by weight of the acryl-based segment.

The pressure sensitive adhesive sheet is a sheet shaped pressure sensitive adhesive including an acryl-based base polymer. The acryl-based base polymer contains an acryl-based segment and a urethane-based segment, and a content of the urethane-based segment is 3 to 30 parts by weight based on 100 parts by weight of the acryl-based segment. The urethane-based segment includes at least one urethane chain selected from the group consisting of a polyether urethane and a polyester urethane. The content of the urethane-based segment other than the polyether urethane-based segment is 15 parts by weight or less based on 100 parts by weight of the acryl-based segment.

An alternative polyurethane composition is provided which comprises a reaction product of an azidated polyol and a poly(alkynyl carbamate) prepolymer reacted at a temperature of from 20° C. to 120° C., wherein the poly(alkynyl carbamate) prepolymer comprises a reaction product of a polyisocyanate and a stoichiometric equivalent of an alkynol of the formula (I),
HC≡C—R.sup.1R.sup.2—OH  (I),
and wherein R.sup.1 is an electron-withdrawing group selected from the group consisting of carbonyl, ester, amide, and urethane and R.sup.2 is a linear or branched alkyl chain having from 1 to 15 carbon atoms. The inventive alternative polyurethane composition position may be used to provide adhesives, sealants, films, elastomers, castings, foams, and composites.