CHARACTERIZATION OF CHLOROPRENE AND MALEIC-ANHYDRIDE COPOLYMER BY C-13-NMR SPECTROSCOPY AND PYROLYSIS GC MS

The radical copolymerizations of chloroprene (CP) and maleic anhydride (MAH) were carried out with AIBN in 1,4-dioxane at 60-degrees-C. The monomer reactivity ratios were estimated as r1(CP) = 0.38 and r2(MAH) = 0.07. Microstructures in the copolymer of chloroprene (CP) and maleic anhydride (MAH) were investigated by 75.4 MHz C--13 and 300 MHz H-1-NMR spectroscopies. Resonances were assigned to the monomer sequence dyads CC, CM, and MC (C = chloroprene, M = maleic anhydride). Well resolved fine structure in the C-13-NMR spectra showed that 1,2- and 3,4-structural chloroprene units were negligible in the copolymer. The pyrolysis characterization of the copolymer was also investigated by the pyrolysis gas chromatography mass spectrometry (GC/MS). The fragments of CP and MAH monomers and CP-MAH hybrid dimer, CO, and CO2 were identified after pyrolysis of the copolymer. (C) 1994 John Wiley & Sons, Inc.