Abstract: A process for the production of a pressure-sensitive adhesive composition is provided comprising (1) forming an elastomer composition by mixing in the form of a solution, 33.5 to 95% by weight of an aromatic vinyl-isoprene block copolymer (a) having two or more poly(aromatic vinyl) blocks, 0 to 47.5% by weight of an aromatic vinyl-isoprene diblock copolymer (b), and 5 to 33% by weight of isoprene homopolymer (c) having a weight average molecular weight of 20,000 to 100,000, wherein the elastomer composition has a content of aromatic vinyl monomer unit of 14 to 50% by weight, (2) separating the elastomer composition from the solvent, (3) drying the elastomer composition, and (4) blending a petroleum resin with the elastomer composition made by steps (1)-(3), wherein the amount of the petroleum resin is 10 to 500 parts by weight based on 100 parts by weight of the elastomer composition.

Abstract: A process for the production of a pressure-sensitive adhesive composition is provided comprising (1) forming an elastomer composition by mixing in the form of a solution, 33.5 to 95% by weight of an aromatic vinyl-isoprene block copolymer (a) having two or more poly(aromatic vinyl) blocks, 0 to 47.5% by weight of an aromatic vinyl-isoprene diblock copolymer (b), and 5 to 33% by weight of isoprene homopolymer (c) having a weight average molecular weight of 20,000 to 100,000, wherein the elastomer composition has a content of aromatic vinyl monomer unit of 14 to 50% by weight, (2) separating the elastomer composition from the solvent, (3) drying the elastomer composition, and (4) blending a petroleum resin with the elastomer composition made by steps (1)-(3), wherein the amount of the petroleum resin is 10 to 500 parts by weight based on 100 parts by weight of the elastomer composition.

Abstract: The invention provides an elastomer composition including an aromatic vinyl-isoprene block copolymer (a) having two or more poly(aromatic vinyl) blocks, in an amount more than 10 wt. % and less than 47.5 wt. %; an aromatic vinyl-isoprene diblock copolymer (b) in an amount more than 47.5 wt. % and less than 85 wt. %; and polyisoprene (c) having a weight average molecular weight of 20,000 to 100,000, in an amount more than 5 wt. % and less than 20 wt. %, wherein the composition has an aromatic vinyl monomer unit content more than 14 wt. % and less than 50 wt. %, based on the total amount of the components (a), (b), and (c). The elastomer composition is suitable for providing the pressure-sensitive adhesive composition, which exhibits excellent initial bond strength, peel strength, and holding power, and, even at relatively low temperature, exhibits minimal drop in initial bond strength and peel strength.

Abstract: The invention provides an elastomer composition including an aromatic vinyl-isoprene block copolymer (a) having two or more poly(aromatic vinyl) blocks, in an amount more than 10 wt. % and less than 47.5 wt. %; an aromatic vinyl-isoprene diblock copolymer (b) in an amount more than 47.5 wt. % and less than 85 wt. %; and polyisoprene (c) having a weight average molecular weight of 20,000 to 100,000, in an amount more than 5 wt. % and less than 20 wt. %, wherein the composition has an aromatic vinyl monomer unit content more than 14 wt. % and less than 50 wt. %, based on the total amount of the components (a), (b), and (c). The elastomer composition is suitable for providing the pressure-sensitive adhesive composition, which exhibits excellent initial bond strength, peel strength, and holding power, and, even at relatively low temperature, exhibits minimal drop in initial bond strength and peel strength.

Abstract: The invention provides an elastomer composition which comprises 33.5 to 95% by weight of an aromatic vinyl-isoprene block copolymer (a) having two or more poly(aromatic vinyl) blocks, 0 to 47.5% by weight of an aromatic vinyl-isoprene diblock copolymer (b), and 5 to 33% by weight of polyisoprene (c) having a weight average molecular weight of 20,000 to 100,000, and which has a content of aromatic vinyl monomer unit of 14 to 50% by weight based on the total amount of the components (a), (b) and (c). The invention further provides a pressure-sensitive adhesive composition comprising the elastomer composition and a tackifier resin.