Hindered phenolic antioxidant modified waterborne polyurethane films with excellent thermal stability and anti-aging performance at high temperature

Waterborne polyurethane (WPU) have been widely used in coating, fiber glass sizing and textiles due to their versatile physical and chemical properties. However, WPUs are always suffering from poor stability at high temperatures significantly limit their industrial application. In this paper, we developed an AO-80 modified polycarbonate based WPU (AWPU) with enhanced aging-yellow and thermal stability properties. The introduction of AO-80 not only improves the compatibility of soft and hard segment in WPU by forming hydrogen bond between phenolic hydroxyl in AO-80 and carbonyl group in WPU, but also enables a restrained oxidation radical reaction in WPU at high temperatures. The resulting AWPU could maintain over 90 % transmittance without turning yellow even under oxidation atmosphere at 130 °C for 24 h. The study provided a reference for the microscopic morphology and anti-yellowing mechanism of other hindered phenol antioxidant in waterborne polyurethane.