Study of the oligoester maleinates containing an isocyanuric ring by infrared spectroscopy

Abstract

syqopsisProcesses taking place in crosslinked oligmter maleinates containing an isocyanuric ring were studied by means of infrared and ESR spectroscopy and heating from 110" to 600°C. By determining the optical density of the carbonyl groups a t 1690 cm-l, of the CH-groups a t 1460 cm-1, ether and ester groups a t 1120 and 1260 cm-1, and vinyl groups a t 935 and 990 cm-l, their mutation by hardening and tempering of the polymers was followed. The investigation shows that the carbonyl absorption of the oligoester maleinates containing an isocyanuric ring is double and that of the oligoester propyleneglycol maleinate phthalate is single. By modification of the isocyanuric oligoester maleinates with phthalic, adipic, sebacic, and other acids, an increase of the speed of isomerization of maleic groupings to fumaric is observed. By building of isocyanuric links in oligoester maleinates, a more stable structure is obtained. Above 33O0C, isocyanuric l i i probably regroup into polycyanic links. The typical carbonyl absorption precipib ously decreases a t 400°C and disappears altogether a t 600°C. On the basis of the investigations carried out, it is assumed that, in the process of hardening and thermodestruc tion of the polymers investigated, and radical processes obviously play an essential part