Influence of Ester and Ether Groups on Solution Properties of Polyurethanes

Abstract

Viscometric data in non-theta solvent were utilized for determination of the poly(ester-urethane)s and poly(ether urethane)s conformational transitions and of the unperturbed dimensions. The influence of soft and hard segments was observed for poly(ester-urethane)s. The samples with 2,4-tolylene diisocyanate in hard segments have smaller unperturbed dimensions compared with the samples containing 4,4′-methylene diphenylene diisocyanate, which are believed to possess significant chain rigidity. The crosslinking tendency in synthesis of polyurethanes with ether groups - by reaction of chain end -NCO in prepolymer with the hydrogen from -NHCOO-groups - and in solutions explains the anomalies observed in solution properties.