Effect of nanorough surface in evaluating the handle of nanofiber web

The effect of frictional coefficient on handle measurement of the nanofiber webs was studied by using a home-made apparatus. The instrument measures directly the frictional coefficient between the finger and the nanofiber web. The stick-slip phenomenon was observed in friction of polyurethane (PU) nanofiber webs and nylon nanofiber laminate-coated nylon 6 fabrics above the critical load of ∼1 N. Conventional friction test was also carried out on Kawabata Evaluation System (KES FB 4) which did not show stick-slip process up to a load of 0.49 N. Moreover, it was found that the frictional coefficient of PU nanofiber webs and nylon nanofiber laminate-coated nylon 6 fabrics decreased despite the increase in applied load, indicating that Coulomb-Amonton's friction law did not hold good. However, conventional nylon fabric was found to exhibit friction behaviour independent of the applied load. Possible reason attributed to these phenomena is discussed in terms of the repeated adhesion-shear deformation behavior between the nanofiber web and the forefinger.