STEREOCHEMICAL STRUCTURE OF POLY(CYCLOHEXYL ACRYLATE) STUDIED BY ONE-DIMENSIONAL AND 2-DIMENSIONAL C-13-H-1 SPECTROSCOPY

The stereochemical structure of poly(cyclohexyl acrylate) (PCHA) prepared under different polymerization conditions was studied by the combination of one- and two-dimensional C-13 NMR methods. The assignments of the triad, tetrad, and pentad signals were carried out according to conformational and configurational approaches. In general, the sensitivity of the observed C-13 NMR signals assigned to sequences of triad and tetrad is well reproduced by the C-13 chemical shifts estimated via the gamma-gauche effect method. For PCHA prepared by radical and anionic polymerization (using different solvents and catalysts), a first-order Markov model is required to fit the observed intensities at the tetrad and pentad level, rather than the classical Bernoullian statistics.