Hydrogen bonding in polymer mixtures

Abstract

Abstract The enthalpy–infrared frequency shift correlation for simple acids and bases is extended to study hydrogen bonding in polymer systems. The acidity of a polymer is calibrated by comparing the shifts in hydroxyl absorption frequency of the acidic polymer when mixed with a series of bases with the corresponding spectral shifts of known acids with the same bases. The basicity of a polymer is calibrated by measuring the hydroxyl frequency shifts of known acids when mixed with the basic polymer. For polymers containing carbonyl groups, the shift in carbonyl absorption is also a measure of basicity. The acidity and basicity constants obtained for polymers are in good agreement with the values for small‐molecule analogs. The enthalpies of hydrogen bond formation in polymer mixtures are calculated from the acidity or basicity constants.