ACRYLIC COPOLYMER, ACRYLIC PRESSURE-SENSITIVE ADHESIVE COMPOSITION, ACRYLIC PRESSURE-SENSITIVE ADHESIVE TAPE OR SHEET, AND ACRYLIC ADHESIVE COMPOSITION

摘要

Acrylic copolymers are provided which have polymeric portions having different polarities or glass transition temperatures, which permit easy selection of combinations of such polymeric portions having different polarities or glass transition temperatures, which increase a design freedom and which are applicable for diverse uses. Acrylic copolymers including a polymeric backbone portion prepared via copolymerization of (a) an alkyl (meth)acrylate ester containing 1 - 14 carbon atoms in the alkyl, (b) an olefinic polymer or copolymer terminally modified by a free-radically polymerizable unsaturated double bond and (c) a polymer terminally modified by a free-radically polymerizable unsaturated double bond and having a number average molecular weight of 2,000 - 30,000 and a glass transition temperature of at least 30 DEG C and comprised chiefly of the alkyl (meth)acrylate ester, and a polymeric branch portion grafted to the polymeric backbone portion and having a lower polarity and different glass transition temperature than the polymeric backbone portion.