1979 Volume 36 Issue 5 Pages 329-335
Dilute aqueous solution viscosities of poly (vinyl alcohols) (I) which were prepared by solution polymerization of vinyl acetate in higher primary alcohols were measured. Huggins' constant obtained from Schulz-Blaschke's equation, kS′ of conventional I is 0.4-0.5 depending slightly on the degree of polymerization, while kS′ of PVA prepared in cetyl and stearyl alcohols are higher than 0.5 and increase with the decrease of the degree of polymerization. In the case of I prepared in a lower alcohol than myristyl no abnormality in kS′ was observed. In dilute dimethyl sulfoxide solution of the polymers as well as in dilute acetone solution of re-acetylated polymers, no abnormality was also observed. Degree of polymerization of I derived from stearyl alcohol was calculated from the intrinsic viscosities of aqueous solution. It was larger by tens of % than the values calculated from the viscosities of dimethyl sulfoxide and acetone solutions. These results show the existence of intermolecular interaction or hydrophobic bond between the alkyl end groups of I in aqueous solution which are introduced by chain-transfer reaction during the polymerization.
