Incremental calculation of sequence distribution of poly(butyl acrylate)

The carbonyl signal in the 100MHz C-13 NMR spectra of both poly( n- butyl acrylate) and poly( t- butyl acrylate) exhibit configurational sensitivity up to pentads. Since the attribution of respective sequences cannot be performed in a straightforward manner, a method of incremental calculation of chemical shifts of individual sequences has been applied. The simulated spectrum for PnBA obtained in this way required only slight corrections to match the experimental carbonyl signal. This method can therefore be extended to determine the configurational sequences in acrylic copolymers containing n- butyl acrylate units.