Electrical Resistance Measurements on Fibers and Fiber Assemblies

Abstract

The resistance of single textile fibers and assemblies of these fibers has been studied because of its relation to the effects of static electricity in fibrous materials. An apparatus has been con structed to measure resistances of fibers and assemblies from 10⁸ to 10 ¹⁶ ohms at specified tem peratures and relative humidities. Results of measurements at 30°C on some natural fibers (wool, cotton, hair, silk) and on some man-made fibers (rayon, acetate, nylon, casein) are given for relative humidities from 52% to 85%. Some other synthetic fibers (Orlon, Dacron, Dynel, polyethylene, Velon) have resistances too high to be measured conveniently with the present apparatus. All of the materials measured were found to be ohmic and largely free from polari zation effects at voltage gradients up to several hundred volts per centimeter, the limiting values used in the study. The resistivities of all materials tested decreased rapidly with increasing moisture content of the material, the resistivity varying inversely as the 7th to 13th power of the moisture content. Reasonable correlations were found to exist between the resistances of fiber assemblies and the constituents thereof.