Study of the Sequence Distribution of Poly(neopentyl isophthalate-fumarate) by ¹H Nuclear Magnetic Resonance

Abstract

The sequence distribution of poly(neopentyl isophthalate-fumarate) was studied by high-resolution ¹H nuclear magnetic resonance (¹H-NMR). The ¹H-NMR signals of methylic and methylenic protons of the copolyester were split into five and six peaks, reflecting the linkages between neopentyl glycol (N) and two kinds of acids, i.e. isophthalic acid (I) and fumaric acid (F). All of the peaks were assigned and the dyad sequence (F-N-F, F-N-I, I-N-I etc.) distribution of poly(neopentyl isophthalate-fumarate) was clarified on the basis of the ¹H-NMR spectrum. This copolyester was found to be a random polycondensation type, though there was a large difference between I and F concerning the rate of esterification.