Polymers from Multifunctional Isocyanates, 15†

N-(4-cyanatophenyl)maleimide and 2-isocyanato propene were copolymerised to give an alternating copolymer, which is the first example of a polymer having an isocyanate as well as a cyanate reactive functional group in the repeating unit. The polymer analogous reaction with methanol proceeded selectively at the isocyanate groups. Crosslinking of the cyanate-urethane copolymers by cyclotrimerisation of cyanate groups occurred at elevated temperature. Reaction with dibutylamine at 20°C led to complete reaction of both the cyanate and isocyanate moieties in a non-selective manner.