A (meth)acrylic copolymer of the present invention includes a constituent unit (B) derived from a polysiloxane block-containing polymerizable monomer (b) represented by Formula (b1). In Formula (b1), R.sup.30 represents a hydrogen atom or a methyl group, a represents an integer of 2 to 5, b represents a number of 0 to 50, c represents an integer of 0 to 18, d represents a number of 1 to 1000, e represents a number of 1 to 80, R.sup.31 to R.sup.39 each represents an alkyl group, an alkoxy group, a phenyl group, a substituted phenyl group, a phenoxy group, or a substituted phenoxy group.

Provided is a block copolymer composition which contains a block copolymer having a specific molecular structure and has a molecular weight distribution within an appropriate range. A polymerizable composition containing a macromonomer (A) which has a group having a radical-reactive unsaturated double bond at one terminal of a poly(meth)acrylate segment, a vinyl monomer (B), and an organic iodine compound (C), or a polymerizable composition containing a macromonomer (A), a vinyl monomer (B), an azo-based radical polymerization initiator (E), and iodine is polymerized to obtain a block copolymer composition containing a block copolymer in which constitutional units of all blocks are derived from vinyl monomers and at least one block has a branched structure.

Provided is a block copolymer composition which contains a block copolymer having a specific molecular structure and has a molecular weight distribution within an appropriate range. A polymerizable composition containing a macromonomer (A) which has a group having a radical-reactive unsaturated double bond at one terminal of a poly(meth)acrylate segment, a vinyl monomer (B), and an organic iodine compound (C), or a polymerizable composition containing a macromonomer (A), a vinyl monomer (B), an azo-based radical polymerization initiator (E), and iodine is polymerized to obtain a block copolymer composition containing a block copolymer in which constitutional units of all blocks are derived from vinyl monomers and at least one block has a branched structure.

A polymer composition, in which a differential distribution value in a differential molecular weight distribution curve of the polymer composition, as measured by gel permeation chromatography, satisfies Equation 1 and a maximum value of a normalized back-scattering intensity of a 35 wt % base oil solution of the polymer composition, where a size q of a scattering vector of small-angle X-ray scattering at 25° C. is in a range of 0.07 nm.sup.−1 or more and 2 nm.sup.−1 or less, is 40 cm.sup.−1 or more.

A polymer composition, in which a differential distribution value in a differential molecular weight distribution curve of the polymer composition, as measured by gel permeation chromatography, satisfies Equation 1 and a maximum value of a normalized back-scattering intensity of a 35 wt % base oil solution of the polymer composition, where a size q of a scattering vector of small-angle X-ray scattering at 25° C. is in a range of 0.07 nm.sup.−1 or more and 2 nm.sup.−1 or less, is 40 cm.sup.−1 or more.

Disclosed are polymer polyol compositions that include polymer particles produced from an ethylenically unsaturated compound resulting from the reaction of an amine-reactive ethylenically unsaturated compound with an amino diphenylamine, as well as to the use of such polymer polyol compositions in the production of flexible polyurethane foams. The polyurethane foam includes the reaction product of a reaction mixture that includes a polyisocyanate component and a polyol composition that includes the polymer polyol.

Disclosed are polymer polyol compositions that include polymer particles produced from an ethylenically unsaturated compound resulting from the reaction of an amine-reactive ethylenically unsaturated compound with an amino diphenylamine, as well as to the use of such polymer polyol compositions in the production of flexible polyurethane foams. The polyurethane foam includes the reaction product of a reaction mixture that includes a polyisocyanate component and a polyol composition that includes the polymer polyol.

A molded product with excellent transparency can be obtained by using a polymer (D) obtained by suspension polymerization of a monomer mixture (1) containing (a) to (c) below: (a) 5-60 mass % of a specific macromonomer; (b) 5-60 mass % of the raw material monomer of a homopolymer (B) that has a solubility parameter that is different by 0.25 or more from the solubility parameter of the macromonomer (a); and (c) 10-80 mass % of the raw material monomer of a homopolymer (C) that has a solubility parameter that is different by less than 0.25 from the solubility parameter of macromonomer (a).

A molded product with excellent transparency can be obtained by using a polymer (D) obtained by suspension polymerization of a monomer mixture (1) containing (a) to (c) below: (a) 5-60 mass % of a specific macromonomer; (b) 5-60 mass % of the raw material monomer of a homopolymer (B) that has a solubility parameter that is different by 0.25 or more from the solubility parameter of the macromonomer (a); and (c) 10-80 mass % of the raw material monomer of a homopolymer (C) that has a solubility parameter that is different by less than 0.25 from the solubility parameter of macromonomer (a).

There is provided a new pressure-sensitive adhesive resin composition that can have adhesiveness to the extent of being peelable in a room temperature condition, has fluidity by hot-melting, and can finally be crosslinked to firmly bond adherends to each other. There is proposed a pressure-sensitive adhesive resin composition comprising 100 parts by mass of an acrylic copolymer (A), 0.5 to 20 parts by mass of a crosslinking agent (B), and 0.1 to 5 parts by mass of a photopolymerization initiator (C), wherein the acrylic copolymer (A) is a graft copolymer having a weight average molecular weight of 5.0×10.sup.4 to 5.0×10.sup.5, contains as a trunk component of the graft copolymer a repeating unit derived from a (meth)acrylate, contains as a branch component of the graft copolymer a repeating unit derived from a macromonomer having a number average molecular weight of 5.0×10.sup.2 or more and less than 6.0×10.sup.3, and contains the repeating unit derived from the macromonomer in the acrylic copolymer (A) in a proportion in a range of 0.1 to 3 mol %.