The Interaction of Hair Fibers with Alkali Bromide Solutions

Abstract

The interaction of hair with alkali bromide solutions has been studied by measuring the amount of salt taken up from a given solution, using a radioactive-tracer technique, and the amount of water taken up from the solution, using a gravimetric technique. It has been found that: ( 1) alkali bromides are taken up in a manner primarily dependent on the activity of the salt in the solution; ( 2) the amount of water absorbed is increased over the normal regain by the presence of the salt in the hair; ( 3) the ratio of salt to water is greater in the hair than in the external solution; ( 4) the rate of absorption of the salt is slower than the rate of diffusion of the same salt in water; ( 5) both rates and equilibrium are temperature- sensitive. The interpretation of these results in terms of various simple models of the absorption process is discussed.