Barrier and mechanical properties of water-based polyurethane-coated hydroentangled cotton nonwovens

Imparting new functionalities by means of coating on textiles is a step to widen the span of their characteristics and potential applications in different dimensions. Water-based polyurethanes (PU) offer unique and striking mechanical and functional features that have driven strong interest in their utility for various applications while also matching environmental sustainability needs. This research investigates the effects of PU coating on hydroentangled cotton nonwovens. The coated and uncoated nonwovens produced by various combinations were evaluated for their structure and physical properties such as fiber structure, tensile strength, water contact angle, surface energy, air permeability, pressure drop, and water absorbency. The changes in surface structure of nonwovens after coating were analyzed through scanning electron microscope. Additionally, stretchability and stretch recovery of the webs showed improvement as determined by cyclic loading and unloading tests. Cotton nonwovens generally have poor recovery due to the nature of the fiber and the web structure with very low stored energy. The results show that integration of PU on cotton nonwovens can be a promising approach to impart elasticity to cotton webs with endowed tensile strength and vast increase in recovery characteristics.