Cotton Fibers as Means of Transmitting Water Vapor

Abstract

The water vapor transmission of fibers can be measured independent of any air space surrounding the fibers, by using sections cut from embedments of the fibers in polyacrylic resins. The rate of water vapor transmission, measured as the diffusion constant, is larger for cotton than for rayon, wool, nylon, or Dacron. The respective diffusion con stants are on the order of 134. 56. 39, 8 and 7 × 10 ⁴ cm.² sec., under the relatively moist conditions of the tests, between 54 and 93% relative humidity.

White the possible influence of air in the lumen of cotton has not been completely evaluated, there is evidence that such influence has been reduced if not eliminated. How , ever, this same evidence indicates that the cotton fibers were in part in an altered condition as a result of the embedment. Even so, the results suggest that cotton is a good choice of fiber for high water vapor transmission along the fiber.