Stress Relaxation of Fibers as a Means of Interpreting Physical and Chemical Structure'

Abstract

A summary of some preliminary studies on the stress-relaxation behavior of synthetic and cellulosic textile fibers in distilled water and hydrochloric acid is reported in this paper. The results are interpreted in terms of the molecular and physical structures of these materials. Identical stress-relaxation behavior of many diverse materials in dis tilled water indicates that the relaxation is caused by scission of the weaker secondary linkages. It is concluded that the drastic reduction in stress following addition of hydro chloric acid is caused by the rupture of primary bonds. Widely differing relaxation behavior of a series of synthetic fiber samples having different draw ratios is directly attributable to the degree of order of these fibers.

Stress-relaxation measurements on the cellulosic fibers in hydrochloric acid are inter preted in terms of relative accessibility. The data presented show that the relative acces sibility is a function of the concentration of the acid reagent and the temperature at which measurements are made. Relative accessibility data reported in the literature are compared with values obtained from stress-relaxation measurements for a number of cellulose samples. All the samples indicate the same general ranking as a function of fiber type, but the results vary widely in reported values.