A multi-phase silicone acrylic hybrid visco-elastic composition prepared by polymerizing an ethylenically unsaturated monomer and a silicon-containing pressure sensitive adhesive composition comprising acrylate or methacrylate functionality in a first solvent in the presence of an initiator, removing the first solvent, and adding a second solvent to form the multi-phase silicone acrylic hybrid visco-elastic composition. Alternatively, a multi-phase silicone acrylic hybrid visco-elastic composition prepared by polymerizing an ethylenically unsaturated monomer and a silicon-containing pressure sensitive adhesive composition comprising acrylate or methacrylate functionality in a first solvent in the presence of an initiator, adding a processing solvent having a higher boiling point than the first solvent, applying heat to selectively remove a majority of the first solvent, removing the processing solvent, and adding a second solvent to form the multi-phase silicone acrylic hybrid visco-elastic composition. The phase arrangement of the multi-phase silicone acrylic hybrid visco-elastic compositions is selectively controlled by selection of the second solvent.

An adhesive composition includes a first acrylic polymer preparable from first components and a second acrylic polymer. The first components comprising i) a branched first alkyl (meth)acrylate having from 4 to 22 carbon atoms, and ii) at least one of acrylic acid and methacrylic acid. The second acrylic polymer is preparable from second components comprising iii) at least one second alkyl (meth)acrylate having from 4 to 22 carbon atoms, iv) a (meth)acrylamide represented by the formula ##STR00001##
wherein R.sup.1 is H or methyl, and R.sup.2 and R.sup.3 each independently represents H or an alkyl group having from 1 to 8 carbon atoms, or taken together R.sup.2 and R.sup.3 may form a divalent alkylene group having from 4 to 6 carbon atoms, and v) at least one high T.sub.g macromer having a terminal free-radically polymerizable unsaturated group, the high T.sub.g macromer having a T.sub.g of at least 45 C. Based on the combined total weight of the at least one first acrylic polymer and the at least one second acrylic polymer, the at least one second acrylic polymer is present at a level of from 5 to 40 percent by weight. Methods of making the adhesive composition are also disclosed.

The present invention is a copolymer of a monomer mixture including about 25 to about 80 parts by mass of an alkyl (meth)acrylate, approximately 15 to approximately 50 parts by mass of a hydroxyl group-containing monomer, and approximately 5 to approximately 25 parts by mass of a macromer having a glass transition temperature (Tg) of approximately 50 C. or higher. The copolymer contains substantially no acidic groups.

Multigraft copolymers having various structures, e.g., comb and centipede structures, can be prepared from emulsion copolymerization of monomers and macromonomers. The emulsion copolymerization can be initiated by a thermally activated radical initiator or a redox initiation system. The multigraft copolymers can have high molecular weight and/or a large number of branch points. Elastomer or adhesive compositions of the copolymers can be prepared. Also described are poly(n-alkyl acrylate-graft-styrene) multigraft copolymers.

Multigraft copolymers having various structures, e.g., comb and centipede structures, can be prepared from emulsion copolymerization of monomers and macromonomers. The emulsion copolymerization can be initiated by a thermally activated radical initiator or a redox initiation system. The multigraft copolymers can have high molecular weight and/or a large number of branch points. Elastomer or adhesive compositions of the copolymers can be prepared. Also described are poly(n-alkyl acrylate-graft-styrene) multigraft copolymers.

There is provided a (meth)acrylic copolymer with which a pressure-sensitive adhesive layer exhibiting excellent low temperature coatability and exhibiting holding power and excellent base material contamination resistance even in a case of being irradiated with a low dose of UV irradiation can be formed. The (meth)acrylic copolymer of the present invention comprises a constituent unit a derived from a macromonomer and a constituent unit b derived from a monomer represented by Formula (b), where a content of the constituent unit b is 0.01% to 25% by mass with respect to a total mass of the (meth)acrylic copolymer. In Formula (b), R.sup.A and R.sup.B each independently represent an alkyl group, a carboxy group, or a halogen atom, n represents an integer of 0 to 5, m represents an integer of 0 to 4, and X represents a (meth)acryloyloxy group or a (meth)acryloyloxyalkyleneoxy group.