Abstract: A composition with improved storage viscosity is provided. The composition contains a (meth)acrylic-based copolymer (A?) and an epoxy compound (C). A molecule of the (meth)acrylic-based copolymer (A?) includes an XY diblock structure or an XYX triblock structure therein. A number of repeating units which are derived from a (meth)acrylic ester monomer having an alkoxysilyl group and are included in an X block is 1.0 or more on average; an amount of repeating units which are derived from a (meth)acrylic ester monomer having an alkoxysilyl group and are included in a Y block is 0% by weight to 3% by weight, with respect to a weight of all repeating units included in the Y block. A molecular weight distribution (Mw/Mn) of the (meth)acrylic-based copolymer (A?) is 1.8 or less.

Abstract: In a method for polymerizing a (meth)acrylic monomer by living radical polymerization in the presence of a transition metal complex catalyst, the combined use of a multidentate amine (A), a base (B) and a reducing agent (C) makes it possible to achieve a rapid polymerization reaction and high monomer conversion rate and obtain a polymer having a narrow molecular weight distribution when 5-30 ppm by weight of copper atoms and a mole amount of 7 mmol % or less of multidentate amine (A) are used, each based on the total amount of (meth)acrylic monomer introduced.

Abstract: An object of the present invention is to provide a damping material which exhibits a very high vibration-damping (energy-attenuating) performance against vibrations in a low frequency range (several hertz) or a higher frequency range in a specific temperature range near room temperature (20 to 20° C.), which can be controlled in vibration-damping performance at will to target performances not only in a low-temperature and high-frequency range but also in a very low specific frequency range and a specific temperature range, and which can be designed with a high flexibility. The object is attained by a composition for damping material including a branched polymer (A), and a resin (B), wherein the content by percentage of the branched polymer (A) is from 15 to 85% both inclusive by weight for 100% by weight of the total of the branched polymer (A) and resin (B).

Abstract: In a method for polymerizing a (meth)acrylic monomer by living radical polymerization in the presence of a transition metal complex catalyst, the combined use of a multidentate amine (A), a base (B) and a reducing agent (C) makes it possible to achieve a rapid polymerization reaction and high monomer conversion rate and obtain a polymer having a narrow molecular weight distribution when 5-30 ppm by weight of copper atoms and a mole amount of 7 mmol % or less of multidentate amine (A) are used, each based on the total amount of (meth)acrylic monomer introduced.