Vinyl polymer powder, curable resin composition and cured substance
View Patent ↗Disclosed is a vinyl polymer powder which is superior to dispersibility to curable resin compositions, which immediately gives a gel state for curable resin compositions by short-time heating with predetermined temperature, which is with high ion concentration, and which is useful as a pre-gel agent suitable for fields of electronic materials, to provide a curable resin composition comprising the vinyl polymer powder, and to provide a cured substance of the curable resin composition. The vinyl polymer powder of the present invention has an acetone-soluble component of 30% by mass or more, mass average molecular weight of the acetone-soluble component of 100,000 or more, a content of an alkali metal ion of 10 ppm or less, and a volume average primary particle size (Dv) of 200 nm or more.
1. A curable resin composition, comprising:
1 to 30% by mass of a vinyl polymer powder; and
70 to 99% by mass of a curable resin;
wherein the vinyl polymer powder comprises a primary particle having a core shell morphology wherein at least one of a solubility parameter and molecular weight is different for the core and the shell of the primary particle,
an acetone-soluble component of the vinyl polymer powder is 30% by mass or more,
a mass average molecular weight of the acetone-soluble component is 100,000 or more,
a content of an alkali metal ion of the vinyl polymer powder is 10 ppm or less,
a volume average particle size (Dv) of the primary particle is from 500 nm to 830 nm, and
the curable resin is an epoxy resin which is liquid at 25° C.
2. A cured substance obtained by curing of the curable resin composition according to claim 1 .
3. A sealing material for a semiconductor, comprising in a cured form, the curable resin composition according to claim 1 .
4. A sheet product, comprising in a cured form, the curable resin composition according to claim 1 .
5. The vinyl polymer powder according to claim 1 , wherein a sulfate ion (SO 4 2− ) content is 20 ppm or less.
6. The vinyl polymer powder according to claim 1 , wherein a ratio (D v /D n ) of the volume average primary particle size (D v ) to a number average primary particle size (D n ) is 3.0 or less.