Studies in the kinetics of removal of water from cellulosic fibers

Abstract

A study has been made of the kinetics of the removal of water from native, alkaliswollen, and regenerated cellulosic fibers under well defined conditions of experiment. In all cases, the rate of evaporation curve appears to be made up of five distinct and separate portions, and there are four points on each curve at which sudden changes of direction take place. From the changes in the rates of removal of water, attempts have been made to determine the amounts of water present in cellulosic fibers with different degrees of association with the fiber substance and to compare these values with those recorded by other workers employing different techniques. Removal of primary adsorbed water from different cellulosic fibers could be best represented by three distinct phases, the first two of which obey kinetics of reaction of first order and with apparent activation energy of the order of 8-9 kcal./mole. An attempt has also been made to calculate the radii of capillaries present in water-swollen cellulosic fibers.