ABSTRACT
Probably the most apparent and common phenomenon observed in measurements of contact angle of water on a polymer surface is the discrepancy found between advancing and receding contact angles. This discrepancy, found in both sessile
droplet and Wilhelmy contact angle measurements, is referred to as contact angle hysteresis [1-3, 5-10]. Many factors are known to influence contact angle hysteresis, such as surface configuration change, swelling, crystallinity, surface roughness, adsorption/desorption, and the energy level of surface electrons. Contact angle is,
in principle, a complex function of any one or more of these factors. For low surface energy polymers, contact angle hysteresis is mostly due to surface configuration change.
