| 摘要 |
An object of the present invention is to provide a rubber-containing graft polymer powder which uses 1,3-butadiene and by which an encapsulant for a solar cell and an interlayer film for laminated glass that are excellent in corrosion resistance, impact resistance, transparency, weather resistance, heat resistance and economic efficiency can be achieved. Provided is a rubber-containing graft polymer powder for polyvinyl acetal for an encapsulant for a solar cell or an interlayer film for laminated glass, in which an amount of an acidic component eluted by a hot water test is 0.10 KOHmg/g or less. It is preferable that the rubber-containing graft polymer powder be obtained by conducting the graft polymerization of a vinyl monomer in the presence of a rubbery polymer obtained by polymerizing a monomer (x) containing a conjugated diene (x1) and an acrylic acid alkyl ester (x2) having an alkyl group having from 2 to 8 carbon atoms and coagulating this. |
