A liquid molding resin component for use in a reaction injection molding process includes a liquid resin reaction monomer including metathesis polymerizable cycloolefin and a plurality of nonswelling mica. The plurality of nonswelling mica have an average particle size in a range of about 35 micro m to about 500 micro m and have a bulk density in a range of about 0.10 g/ml to about 0.27 g/ml. Further, a liquid resin component system for use in a reaction injection molding process includes a plurality of liquid resin components that each include a reaction monomer including metathesis polymerizable cycloolefin. At least one of the liquid resin components includes a catalyst component of a metathesis polymerization catalyst system and at least one of the liquid resin components includes an activator component of a metathesis polymerization catalyst system, and at least one of the liquid resin components includes a plurality of nonswelling mica having an average particle size in a range of about 35 micro m to about 500 micro m and having a bulk density in a range of about 0.10 g/ml to 0.27 g/ml.
