Other preferred co-reactive monomers may be prepared by reacting one equivalent (1 mole) of a lower alcohol such as methyl-, ethyl-, propyl-, n-butyl-, isobutyl- or isopentyl-alcohol with two equivalents (1 mole) of 2,4 toluene diisocyanate to produce the corresponding 2-isocyanate-4-urethane toluene monoisocyanate product.