Synthesis and characterization of phenoxy resins prepared from diglycidyl ether of bisphenol a and various aromatic dihydroxyl monomers

This work describes the synthesis of various phenoxy resins by in situ fusion reaction of aromatic dihydroxyl and low molecular weight liquid diglycidyl ether of bisphenol A (DGEBA) with an aryl phosphonium salt catalyst. FTIR and 1H-NMR spectra and GPC analyses were performed to characterize the resins. Analyses results indicated that resins have an adequate high molecular weight and physical properties when the reaction occurred after 5–10 min at 225–230°C. In addition, DSC and TGA analyses were performed to investigate the thermal properties of these phenoxy resins. According to these results, the lack of steric hindrance of the molecular structure in these phenoxy resins depressed the changes of Tg and weight loss. A series of phenoxy modified epoxy networks containing narrower polydisperity and higher Mn will exhibit the most significant effect on impact toughness. Moreover, the FTIR spectrum of the phenoxy resin as a function of temperature correlates well with the glass transition temperature. Furthermore, results presented herein demonstrate effective miscibility with thermoplastic polyurethane elastomer (TPU). © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 2369–2376, 1999