Specific interactions in blends of poly(ethylene oxide) and poly(bisphenol A-co-epichlorohydrin): FTIR and thermal study

Blends of poly(ethylene oxide) (PEO) of high molecular weight with poly(bisphenol A-co-epichlorohydrin) (PBE) with high epoxy equivalent were studied spectroscopically, thermally and morphologically. As similar systems of low molecular weight, a single Tg was observed for all blends, indicating miscibility. A progressive decrease in the degree of crystallinity and in the size of the PEO spherulites as the PBE is added is also observed. Quantitative analysis from FTIR spectra provided determination of specific interactions between the constituents and their variation with PEO content. Simulations were performed utilising the spectra of the pure polymers to confirm that the observed changes in the experimental spectra of the blends were due to interaction between the polymers.