Journal of Polymer Science Part A: Polymer Chemistry, Vol.37, No.5, 533-543, 1999
Microstructural characterization of acrylonitrile/pentyl acrylate copolymers by one and 2-D NMR spectroscopy
Acrylonitrile/pentyl acrylate (A/P) copolymers of different monomer composition were prepared by solution polymerization using benzoyl peroxide as initiator. Copolymer compositions were determined by elemental analysis and quantitative (CH)-C-13-H-1-NMR spectroscopy. The comonomer reactivity ratios, determined by both Kelen Tudos (KT) and nonlinear error in variables (EVM) methods are r(A) = 0.75 and r(p) = 0.45. 2-D heteronuclear correlation spectroscopy (HSQC) was used to simplify the complex H-1 spectra of A/P copolymers in terms of configurational and compositional sequences. The microstructure was obtained in terms of the distribution of A- and P-centered triad sequences from (CH)-C-13-H-1-NMR spectra of the copolymers. The copolymerization mechanism was found to follow a first order Markov Model.
Keywords:GLASS-TRANSITION TEMPERATURE;COMPOSITIONAL ASSIGNMENTS;SEQUENCE DETERMINATION;C-13-NMR SPECTROSCOPY;RESONANCE;H-1