Frictional Study of Woven Fabrics: The Relationship between the Friction and Velocity of Testing D. Hermann, 1 S. S. Ramkumar, 2 P. Seshaiyer, 1 S. Parameswaran 3 1 Department of Mathematics and Statistics, Texas Tech University, Lubbock, Texas 79409-1163 2 Institute of Environmental and Human Health, Texas Tech University, Box 41163, Lubbock, Texas 79409-1163 3 Department of Mechanical Engineering, Texas Tech University, Lubbock, Texas 79409-1163 Received 25 June 2003; accepted 4 November 2003 ABSTRACT: A simple friction factor has been devised to characterize the frictional properties of textile materials. The friction factor enables universal comparisons among differ- ent textile materials. A poly(methyl methacrylate) sled has been used as a standard friction substrate to characterize the friction of a woven cotton fabric. The influence of the veloc- ity of testing on the frictional characteristics has been stud- ied in detail with the novel friction factor. This study elab- orates the relationship between the speed of testing and the new fabric friction factor. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2420 –2424, 2004 Key words: fibers; surfaces; structure-property relationships INTRODUCTION Very recently, there has been a major upsurge in the research on the frictional characterization of polymeric textiles, primarily because of the need for a standard- ized friction testing method. 1–7 Textile materials have been known to deviate from Amontons’ law of fric- tion. 8 –11 This necessitates the evaluation of friction over a range of applied normal loads. 1–7,12 Howell and Mazur’s 10 study of fiber friction proved the deviations from Amontons’ law. A subsequent study by Wilson 8 further proved the failure of Amontons’ linear friction law in fabrics. The importance of friction to the overall quality and mechanical properties of solid polymers and textiles has been well researched and docu- mented. 13–15 Briscoe and Tabor 13 emphasized the relationship between the friction and wear properties of polymers and their bulk properties. Pierce 15 stressed the importance of friction to the overall qual- ity or hand of fabrics, but he did not endeavor to experimentally measure the frictional properties. It is known that the frictional properties of textile materials depend on a number of testing parameters, such as the applied normal load, the area of testing, the speed of testing, and the nature of the contacting surfaces. 8,11,16 –19 There is a plethora of literature available on the influ- ence of applied normal loads and the area of testing on the frictional properties of textiles. However, there is a paucity of data on the influence of testing speeds on the frictional properties of textile materials. Studies by Ajayi 16 and Virto and Naik 20 have shown that the sliding speeds have a limited influence on the fric- tional properties. Most recently, Ramkumar et al. 21 studied the effects of sliding speeds on the frictional properties of nonwoven fabrics. Their results indi- cated that the frictional resistance increased with an increase in the speed of testing. However, this study did not attempt to examine the effect of sliding speeds on the frictional characteristics of a woven fabric. Wo- ven fabrics are conventional and commodity textile products that are used in apparel goods. Therefore, it is necessary to evaluate the frictional properties of woven fabrics. Moreover, the influence of sliding speeds on the frictional properties of woven fabrics has to be evaluated because of the need for a standard- ized friction evaluation method. This article reports on the effects of different sliding velocities on the friction of a cotton woven fabric at different applied load levels. A sliding friction appa- ratus has been used to measure the friction over a range of applied normal loads. Previous studies have used this apparatus to obtain two friction values: fric- tion factor C and friction index n (nondimensional). 1– 6, 16,18 More recently, Ramkumar et al. 1 used this sliding friction apparatus to derive friction parameter K for characterizing the frictional properties of a set of 1  1 rib-knitted cotton fabrics. K is mathematically logical and overcomes the difficulty associated with the com- mon friction parameter C. However, results from a very recent study have shown that characterizing the The friction factor used in the article was originally con- ceived by S. S. Ramkumar. Correspondence to: S. S. Ramkumar (s.ramkumar@ttu.edu). Contract grant sponsor: U.S. Army Soldier Biological and Chemical Command (SBCCOM); contract grant number: DAAD 13-00-C-0051 (to S.S.R.). Journal of Applied Polymer Science, Vol. 92, 2420 –2424 (2004) © 2004 Wiley Periodicals, Inc.