. . . "Due to their commercial availability, structure (XIV) is preferably a derivative of one of the following: 4,4'-biphenol, wherein x is 0, and each R1 is hydrogen; BPA, wherein x is 1, each R1 is hydrogen, and each R2 is a methyl group; or 4,4'-(hexafluoroisopropylidene)diphenol, commonly known as hexafluorobisphenol A, wherein x is 1, each R1 is hydrogen, and each R2 is trifluoromethyl." . .