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.
本发明的目的是提供一种使用
1,3-丁二烯的含橡胶接枝聚合物粉末,通过这种粉末可以获得耐腐蚀性、抗冲击性、透明性、耐候性、耐热性和经济效益优异的太阳能电池封装剂和夹层
玻璃中间膜。
本发明提供了一种用于太阳能电池封装剂或夹层
玻璃中间膜的聚
乙烯醇缩醛的含橡胶接枝聚合物粉末,其中经热
水测试洗脱的酸性成分的量为 0.10 KOHmg/g 或更少。含橡胶的接枝聚合物粉末最好是在
乙烯基单体存在下进行接枝聚合而得到的,
乙烯基单体是通过聚合含有共轭二烯(x1)和具有 2 至 8 个碳原子烷基的
丙烯酸烷基酯(x2)的单体(x)并使其凝结而得到的橡胶聚合物。