Surface wetting characteristics of cellulosic fibers

Surface wetting behaviors of cotton and two rayons, one a regular crenulate d and the other a trilobal (Galaxy), all stripped of topically applied fini sh, are determined using a sensitive Wilhelmy technique. The contact angles (advancing and receding), work of adhesion, and surface energies are asses sed. For the latter, wetting tests are conducted in two dissimilar fluids, deionized ultra filtered water and methylene iodide, whose polar and disper sive contributions to surface tensions are known. Kaelble's model is used f or surface energy, providing the magnitude of not only the total energy but also its division into the dispersion and polar components. The results sh ow that the three cellulosic fibers have widely different contact angles an d surface energies. They also have different hysteresis values, assessed by comparing the values obtained from measurements in the receding and advanc ing modes. These differences shed light on differences that exist in their chemical and physical structures.