Low-Temperature Flexible WPU-PDMS Copolymers for Cold-Resistant Coating Applications

The demand for cold-resistant coatings that can be applied at low temperatures is rapidly growing, especially for polar cables requiring extreme cold resistance. These cables also need extreme cold resistance and organic solvent-free or water-dispersion coating resins that do not produce volatile organic compounds. In the current study, to address these issues, waterborne poly(dimethylsiloxane)-appended polyurethane (WPU-PDMS) resins were prepared. FTIR measurements confirmed the structures of the WPU-PDMS copolymers, and EDS mapping images established the presence of the siloxane group. DSC and TGA measurements showed that WPU-S10, with a PDMS-based polyol molar ratio of 10%, had a low glass transition temperature and high thermal stability. WPU-S10 also exhibited a high UV blocking rate and exceptional light resistance. Moreover, WPU-S10 displayed outstanding low-temperature characteristics, including a tensile strength of 1.31 kg/mm 2 , elongation of 190%, and a shape recovery rate of 90% at – 40 ℃. It is evident that the PDMS content contributed to the chain flexibility, significantly increasing low-temperature elongation. Finally, WPU-S10 revealed no deep cracks on the surface after cold bending, demonstrating excellent low-temperature characteristics and cold resistance. Exceptional low-temperature characteristics and cold resistance of WPU-PDMS provide an ideal coating solution for various applications in Arctic conditions.