Effects of Imposing a Temperature Gradient on Moisture Vapor Transfer Through Water Resistant Breathable Fabrics

Abstract

Very often outerwear apparel is made of water resistant yet breathable fabrics, and normally these fabrics have multilayer structures of various polymeric materials. The working mechanisms of water vapor transmission through these fabrics are not well understood. The rate at which these breathable fabrics are able to transmit water vapor is most often measured under standard textile testing conditions of 20°C and 65% relative humidity, but these tests are often little better than useless in predicting a fabric's performance under "real" conditions. The experiments described in this paper are de signed to test breathable fabrics under more realistic conditions. Water is heated to 33°C in order to simulate a sweating body, and the rate at which the vapor is transmitted through various breathable fabrics is measured. Experiments involve ambient temperatures of 6, 10, 15, and 20°C, with the relative humidity held at a constant 65% throughout.

Get full access to this article

View all access options for this article.

References

BS 3546:Part 4, Specification for Water Vapour Permeable Coated Fabrics, 1991.

Butler, N. , A Home in Scotland for W. L. Gore and Associates, Tech. Textiles Int. 7(7), 31-32 (1998).

Collier, J.G. , and Thome, J.R. , ch. 10 in "Convective Boiling and Condensation ," 3rd ed., Oxford Science Publications , Oxford, U.K., 1996.

Comyn, J. , ch. 1 in "Polymer Permeability," J. Comyn , Ed., Elsevier Applied Science Publishers, London, 1985.

Gibson, P. , Kendrick, C. , Rivin, D. , Sicuranza, L. , and Charmchi, M. , An Automated Water Vapor Diffusion Test Method for Fabrics, Laminates, and Films, J. Coated Fabr. 24, 322-345 (1995).

Gibson, P. , Effect of Temperature on Water Vapor Transport Through Polymer Membrane Laminates , U.S. Army Natick Research, Development and Engineering Center Technical Report, NATICKlTR-99/015, 1999.

Gretton, J.C. , Brook, D.B. , Dyson , H.M. , and Harlock, S.C. , A Correlation between Test Methods Used to Measure Moisture Vapour Transmission through Fabrics, J. Coated Fabr. 25, 301-310 (1996).

Gretton, J.C. , Condensation in Clothing Systems, presented at Survival 98 Conference, Leeds, U.K., 1998.

Kannekens, A. , Breathable Coatings and Laminates, J. Coated Fabr. 24, 51-59 (1994).

10.

Lomax, G.R. , The Design of Waterproof, Water Vapour-Permeable Fabrics, J. Coated Fabr. 15, 40-66 (1985).

11.

Lomax, G.R. , Hydrophilic Polyurethane Coatings, J. Coated Fabr. 20, 88-107 (1990).

12.

Osczevski, R.J. , Water Vapor Transfer Through a Hydrophilic Film at Subzero Temperatures, Textile Res. J. 66, 24-29 (1996).

13.

Urquhart, A.R. , ch. 3 in "Moisture in Textile," J. W. S. Hearle and R. H. Peters , Eds., The Textile Institute and Butterworths Scientific Publications, London, 1960.

14.

Van Roey, M., Water-Resistant Breathable Fabrics, J. Coated Fabr. 21, 20-31 (1991).