Sheet molding composition and articles formed therefrom with high char strength

Abstract

A sheet molding compound (SMC) composition formulation including a curable resin, such as unsaturated polyester of vinyl ester, in an ethylenically unsaturated monomer; a low profile additive, in a curable solvent; and an intumescent additive, such as melamine polyphosphate or ethylene diamine phosphate. An article formed of the SMC composition formulation experiences no more than a 100% increase in thickness as compared to an initial thickness of the article after exposure to a flame. The low profile additive is present in the composition and the intumescent additive is present in the composition. The resulting article has a char strength at 3 mm thickness of between 100 and 1,000 Newtons.

Dependencies are inferred from the claim text.