Polymerization of N,N-diglycidylaniline with 10% (w/w) potassium t-butoxide gave soluble polymer with only a small amount of gel (2%), whereas 2% butoxide produced mainly gel (80%). Number-average molecular weights by laC nuclear magnetic resonance (n.m.r.) end-group analysis (supported by gel-phase chromatography) did not exceed about 20 000. The structure of the polymers was established by ~3C n.m.r., and it was shown that the cyclopolymerization reaction produced a mixture of six- and seven-membered rings (each as a mixture of cis and trans isomers), with the ring distribution being probably random. A complete assignment of the n.m.r, spectra was made in terms of these structures. The formation of seven- over six-membered rings was favoured and contrary to Baldwin's rules. The data are relevant to the identification of cyclization reactions that occur in the amine cure of epoxy resins containing N,N-diglycidyl groups
Посилання на статтю:
Cyclopolymerization of N,/V-diglycidylaniline and polymer structure by 13C nuclear magnetic resonance spectroscopy / P. Johncock and A. V. Cunliffe // Polymer. – 1993. – Vol 34. – P. 1933-1940.