in formula (III) and (IIIa); m is 0 or 1; R2 is alkyl or substituted alkyl; R3 is H, alkyl or aryl; R4 is a divalent hydrocarbon group having between 2 and 10 carbon atoms or an alkylene oxy alkylene group; R5 is a group selected from H, alkyl, aryl, organosilyl, or the reaction product of an isocyanate esterification reagent or an etherification reagent with the hydroxyl product formed when R5 i