The ¹H and ¹³C NMR spectra of an alternating ethene/maleic anhydride copolymer and the corresponding acid and sodium salt

The 1 H and 13 C NMR spectra of an alternating ethene/maleic anhydride copolymer and the corresponding acid and sodium salt were reinvestigated with regard to the signals depending on the configuration of the succinyl unit. From these assignments a 85/15 ratio of threo ‐and erythro ‐ succinyl configurations was determined. Threo ‐ and erythro ‐units are statistically distributed. Furthermore, signal splittings were observed due to microtacticity. Explanations are given for the signal fine structure. The polymer chain is atactic but a small degree of stereoregularity can be proved. T 1 values and nuclear Overhauser effect (NOE) factors were determined; they correspond to investigations on other polymers.