Thermal and Crystalline Properties of Waterborne Polyurethane by in situ water reaction process and the potential application as biomaterial

[Display omitted] •The new synthesis process, named “in situ water reaction process”, was developed to obtain polyurethane dispersions.•The novel polyurethane film has a special morphology with nanodots.•The novel polyurethane has lower crystallinity, better thermal resistance and lower mold resistance. Understanding the role of water in waterborne polyurethane synthesis and properties is a central issue. Water may bring some unique and interesting properties and phenomenon for waterborne polyurethane. This paper focus on the impact of the novel water addition procedure on the properties of waterborne polyurethane. The novel poly(neopentyl glycol adipate) (PNA)-based waterborne polyurethane was prepared using the designed in situ water reaction process. As a comparison, waterborne polyurethane was synthesized through the conventional water addition process through prepolymer method. The thermal and crystalline properties of the obtained polyurethanes were detected by XRD, DSC, DMA, POM, TG and SEM. The results indicated that the novel polyurethane dispersion presents unique performance. Furthermore, to explore the application area of the novel polyurethane dispersion, mold resistance experiments were performed. The result suggested that polyurethane dispersion from the novel process is safer and more environmentally friendly than that from conventional water addition process.