Configurational sequence determination of poly(isobornyl acrylate) by NMR spectroscopy

Poly(isobornyl acrylate) (PiBA) was prepared by atom transfer radical polymerization (ATRP). Complete characterization of microstructure of PiBA was carried out using one-dimensional [1H, 13C{1H}] and two-dimensional (HSQC, TOCSY and HMBC) NMR spectra. The methyl, methylene, methine, quaternary and carbonyl carbon resonance signals were found to be sensitive to various configurational sequences. The methine carbon (C12) was assigned up to triad configurational sequences in 13C{1H} NMR spectrum whereas β-methylene carbon resonances were assigned up to diad configurational sequences. The quaternary carbon in 13C{1H} NMR spectrum were resolved completely with the help of HMBC NMR spectrum. The stereoregularity of PiBA was found to be random with mm = 20%, mr = 53%, and rr = 27%.