A method and product thereof made by: reacting a carborane-containing compound and an aromatic compound (below) with a crosslinker having at least two silyl hydrogen atoms. R is alkyl, aryl, alkylaryl, haloalkyl, or haloaryl group. Cb is a divalent carboranyl group. U is an unsaturated hydrocarbon group. Ar1 and Ar2 are each a first aromatic group or a bisphenol residue, where at least one of Ar1 and Ar2 is the first aromatic group. Each Ar is a second aromatic group. Each n is a nonnegative integer. The values n′ and n″ are positive integers and m, w, x, y, and z are 0 or 1. If y is 0 than x and z are 0 and w is 1, and if y is 1 than x and z have different values and w equals z.