The Structure of Polymer Clusters in Aqueous Solutions of Hydroxypropyl Cellulose

Abstract

The viscosity, turbidity, and heat capacity of dilute aqueous solutions of hydroxypropyl cellulose have been studied in a concentration interval of 0.047–1.5 g/l and a temperature interval of 20–80 ∘C. The data obtained testify that, if the temperature does not exceed 40 ∘C, hydroxypropyl cellulose molecules are prolate spheroidal globules with semiaxis lengths of 7 and 490 ˚ A. At temperatures above 70 ∘C, the hydroxypropyl cellulose solution consists of clusters; every cluster is composed of 11 globules and has a prolate spheroidal form with semiaxes of 41 and 490 ˚ A. In the temperature interval from 40 to 70 ∘C, the solution concerned contains both globules and clusters, with the concentration of the latter increasing, as the temperature grows.