Application of 1,2-Dipolar Compounds as a Modifier for Polyaddition of Bisphenol-A Diglycidyl Ether with Epichlorohydrin

Abstract

α-Picolinium-p-bromophenacylide (α-PBPY) was prepared by the reaction of p-bromophenacyle bromide with α-picoline followed by proton abstraction with a base and applied as novel modifier in the polyaddition of bisphenol-A diglycidyl ether with epichlorohydrin as a model system of epoxy novolac resins. The nitrogen ylide has decreased values of epoxide equivalent weight, hydroxyl content, viscosity and specific gravity. The cured epoxy resins (with polyamide, molecular weight 3000, make Hindustan Ciba-Geigy Ltd, at room temperature for 24 h, at 80 ± 1ºC for 2 h) have been characterized by IR, ¹H-NMR, DSC and TGA. On the basis of FTIR., it is concluded that a complex between —OH group of bisphenol-A and α-PBPY is formed and it decreases epoxydation.