@Article{jrm.2022.023011,
AUTHOR = {Sai Gong, Shanglin Xiang, Tingwei Wang, Dongyu Cai},
TITLE = {Towards Solar-Driven Formation of Robust and Self-Healable Waterborne Polyurethane Containing Disulfide Bonds via <i>in-situ</i> Incorporation of 2D Titanium Carbide MXene},
JOURNAL = {Journal of Renewable Materials},
VOLUME = {11},
YEAR = {2023},
NUMBER = {3},
PAGES = {1063--1076},
URL = {http://www.techscience.com/jrm/v11n3/50327},
ISSN = {2164-6341},
ABSTRACT = {Waterborne polymers are vital for coating industry to reduce carbon emissions. However, formation of robust and self-healable films at ambient temperature remains a challenge owing to high energy cost of film formation process. This work reports a solar-driven film formation of waterborne polyurethanes (WPUs) containing disulfide bonds via <i>in-situ</i> incorporation of 2D titanium carbide (MXene) with ability to convert light to heat. Instead of directly mixed with WPUs, MXene is added to join the reaction with isocyanate-terminated pre-polymer before emulsification process. This approach not only prevents aggregation of MXene in water but stabilizes MXene against thermal degradation which is the key hurdle for mass production of MXene/WPU composites. More importantly, our results show that mechanical performance of WPU films under visible light (100 mW/cm<sup>2</sup>) is overwhelmingly competitive with that processed in oven. Furthermore, the existence of disulfide bonds in PU chains enables fast self-healing of micro-cracks under natural visible light which could vanish completely within 40 min. The fractured specimens were repaired under natural visible light for 2 h, and the self-healing efficiency of tensile strength and elongation at break reached over 94.00%.},
DOI = {10.32604/jrm.2022.023011}
}