Investigation on the Friction Coefficient of Indian-Origin Human Hair

Human hair often interacts with polymer grooming tools and fails due to sliding contact and friction. The friction characteristics of human hair under dry and wet conditions at different applied loads are studied using an in-house developed capstan tribometer. Tests were conducted using a healthy Indian-origin female's hair to avoid the effect of various treatments, followed in different individuals. Wet conditions were simulated by spraying water on the cylinder surface in a controlled manner. Compared to dry conditions, the measured friction coefficients showed a greater friction coefficient in wet conditions. In both dry and wet conditions, it was found that the friction coefficient for human hair decreased as the load increased. The contact area under wet conditions differs from dry conditions due to the presence of water and meniscus formation at the interface, contributing to the difference in the friction coefficient.