Synthesis and characterization of N-phenylmaleimide and cyclohexene copolymer

Radical copolymerization of N-phenylmaleimide( PHMI) and cyclohexene(CH) was carried out with 2, 2-azobisisobutyronitrile (AIBN) in various solvents at 60 degrees C. The copolymer composition was determined by elemental analysis and the results showed that the copolymerization of PHMI with CH in chloroform proceeded in homogeneous system to give an alternating copolymer over a wide range of the comonomer composition in the feed. The presence of the formation of the charge-transfer-complex( CTC) between PHMI and CH in chloroform was not detected by using UV spectra and H-1-NMR method. The absence of CTC between monomers showed that the ability of electron donor of CH was very weak and the interaction between PHMI and CH was also very weak and it was free monomers participated in propagation in this polymerization system. Monomer reactivity ratios of PHMI with CH was determined by K-T method and the results are r(1) = 0.012, r(2) = 0. The copolymer was characterized by IR, H-1-NMR and (13) C-NMR spectra and there was cis configuration of CH units in the polymer chains which was determined by analysis for (13) C-NMR spectra. In addition, the copolymer of PHMI and CH showed a high glass transition temperature (T-g) and excellent thermal stability, e. g., the T-g and the initial thermal decomposition temperature (T-d) were 200 degrees C and 350 degrees C, respectively, for the alternating copolymer of PHMI and CH.