Infrared Spectra of the Model Compounds of Polyvinyl Alcohol

on Intramolecular Hydrogen Bond

Abstract

By using heptanetriol-(2, 4, 6) and pentanediol-(2, 4) as a model of polyvinyl alcohol, the infrared spectra of them were measured in chloroform or carbon tetrachloride solution at about 3μ region. Absorption band correspondig to intramolecular hydrogen bonded OH was observed and it was found that heptanetriol-2, 4, 6 forms intramoledular hydrogen bonds as much as possible, so that the number of free OH is nearly one in three hydroxyl groups in a molecule. When phenol as a proton donner or hexamethylene tetramine as a proton acceptor was added to the solution of the above model compounds, the absorption band corresponding to the intramolecular hydrogen bond was reserved. Therefore it appears that polyvinyl alcohol retains its intramolecular hydrogen bond in water solution, because water is weaker than phenol or hexamethylene tetramine in the ability for donating or accepting proton.