Evaluation of contact angle of water proof coated fabric made from melt-blown polyester non-woven and acrylic polymeric materials

Water proof fabrics are hydrophobic in nature. Contact angle measurement is a characterization technique used to gauge how well the water proof fabrics designed and developed is useful in preventing seepage of water through fabric surface. The water-proof coated fabric was developed using polyester non-woven fabric made by melt-blown process as base material. Binder made using acrylic polymer was used for preparation of the water-proof coated fabric using layering technique. Different layer configurations like single and double layers was used to develop the non-woven coated fabric. The developed fabrics was subjected to morphological studies using scanning electron microscope. The water proof coated fabrics was also analyzed for its static contact angle measured using rame-hart instrument. The contact angle was measured for both single layer and double layer water proof fabrics at different positions. The contact angle range was reported from 96° - 58° for single layer water proof coated fabrics. However, for double layer water proof coated fabrics the contact angle reported was in the range of 82°-68°. The contact angle changes for different angle of measurements and orientations. The results show that contact angle is not only a function of hydrophobic character of polyester non-woven fabric base material but also depends on the process parameters like number of layers, the thickness of coating, coating technique and the moisture levels that the acrylic polymer binder coating material absorbs the liquid from its surface. The forces acting on the surface of the coating material mainly influences the contact angle of the coated surface. The water repellency increases with the increase in static contact angle. (paper)