Investigation of microstructure of the acrylonitrile-styrene copolymers by2-D NMR spectroscopy

Acrylonitrile-Styrene (A/S) copolymers were prepared by photopolymerization using uranyl nitrate ion as initiator. The copolymer compositions were det ermined by elemental analysis, and comonomer reactivity ratios were determi ned by nonlinear least squares error in variables method (EVM). The complet e spectral assignment of the C-13 and H-1-NMR spectra were done with the he lp of Distortionless Enhancement by Polarization Transfer (DEPT) and by the two dimensional C-13-H-1 Heteronuclear Single Quantum Correlation (HSQC) a nd TOCSY experiments. The methylene and methine carbon resonance show both stereochemical and compositional sensitivity. The 2-D Total Correlated Spec troscopy (TOCSY) experiment was used to ascertain the Various geminal coupl ing between the methylene protons. (C) 1999 John Wiley & Sons, Inc.