| abstract |
Epoxy molding compositions useful as semiconductor encapsulants, comprising (a) an epoxide compound; (b) as hardener, a polyanhydride of a maleic monomer and at least one alkyl styrene monomer or prepolymers of the polyanhydride and said epoxide compound; (c) a catalyst; (d) about 1 to 80 percent by weight of a silica filler; (e) about 1 to 80 percent by weight of an additional filler selected from the group consisting of calcined clay, antimony trioxide, antimony tetraoxide, calcium silicate, titanium dioxide, calcium carbonate, zinc oxide, magnesium oxide and mixtures thereof; (f) about 0.05 to 2 percent by weight of a silane coupling agent; and (g) about 0.01 to 2 percent by weight of a lubricant selected from the group consisting of carnauba wax, montanic acid ester wax, polyethylene wax, polytetrafluoroethylene wax and mixtures thereof. |