High Water Resistance and Enhanced Mechanical Properties of Bio-Based Waterborne Polyurethane Enabled by in-situ Construction of Interpenetrating Polymer Network

In this study, acrylic acid was used as a neutralizer to prepare bio-based WPU with an interpenetrating polymer network structure by thermally induced free radical emulsion polymerization. The effects of the content on properties resulting waterborne polyurethane-poly (acrylic acid) (WPU-PAA) dispersion and films were systematically investigated. results showed that cross-linking density polymers increased interlocking soft hard phase dislocations in molecular segments double networks tailored increasing acid, leading enhancement mechanical water resistance WPU-PAA films. Notably, increase tensile strength, Young’s modulus, toughness WPU-PAA-110 film 3 times, 8 2.4 times compared WPU-PAA-80, respectively. WPU-PAA-100 best resistance, absorption rate at 96 h only 3.27%. This work provided new design scheme for constructing materials excellent properties.