Studies on the sequence structure of vinyl monomer-N-phenylmaleimide copolymers

The sequence structure of methyl methacrylate (MMA) -N-phenylmaleimide (PMI ) and styrene (St)-PMI copolymers was studied in detail with NMR spectrosco py,MMA-PMI copolymer was in random sequence distribution, and St-PMI copoly mer was alternating in structure. Some stereo information of MMA-PMI copoly mer could be obtained from H-1 NMR result. The sequence length obtained fro m the triad of copolymer by C-1 NMR was in agreement with that calculated f rom the reactivity ratios. From the triad of copolymer by C-13 NMR, the cop olymer chain of MMA-PMI was proved being one order Markov chain. More suita ble propagation reactions were proposed from the deviation of sequence dist ribution of St-PMI copolymer.