Chitosan Oligosaccharide Based Waterborne Polyurethane with UV Resistance and Oxidation Resistance for Functional Fabric

Abstract Chitosan oligosaccharide (COS) is an abundant polysaccharide in nature, which has various functions such as antioxidant and antibacterial. The possibilities of using COS can be extended by applying it to polyurethane materials. Herein, Chitosan oligosaccharide‐based waterborne polyurethane (CWPU) with intramolecular crosslinking network is prepared by using COS as chain extender. The mechanical properties of CWPU are improved, with tensile strength and elongation at break reaching 14.83 MPa and 449.63%, respectively. The DPPH free radical scavenging rate of CWPU increases from 8.43% to 70.98%, indicating that CWPU has favorable antioxidant performance. The tensile strength of the CWPU‐treated fabrics obtained by the padding method improve from 542.77 to 605.33N and there is no significant change in the whiteness of the fabric. Furthermore, the CWPU‐treated fabrics, with the UV protection factor of 30.39 and the UVA transmittance below 3%, can be used as UV‐protective fabrics. This work introduces COS into the molecular structure of polyurethanes to obtain functional PUs, expanding the application of COS in polyurethanes.