High-resolution NMR study on hydrogen bondings in polyether polyurethane zwitterionomers

Abstract

Hydrogen bondings formed in polyether polyurethane zwitterionomers based on 4.4′-diphenylmethane diisocyanate (MDI), methyl diethanolamine (MDEA), and polytetramethylene oxide glycol (PTMO) were studied in concentrated solutions with high resolution 1H NMR spectroscopy. By comparing with the results of a previous wide line NMR study, a direct relationship was found between the degree of phase separation and the amounts of various kinds of hydrogen bondings formed in the system. The formation of hard segment micelles in concentrated solution is proved and high resolution NMR is demonstrated to be a powerful tool to study the morphology of the multiphase polymers.