A strippable catechol-terminated polyurethane coating for large-area radioactive cesium decontamination

Abstract

Efficient and rapid decontamination of radioactive elements is important to prevent radioactive exposure. Herein, we develop a strippable catechol-terminated polyurethane (CPU) coating for effective surface decontamination. Our polyurethane coating can be directly applied to contaminated surfaces via simple spraying or solution casting, followed by rapid drying at room temperature. The resulting coating is easily stripped off with sufficient toughness and adhesion strength, showing superior Cs-137 removal efficiency on stainless steel (similar to 94.9%) and rough cement (similar to 59.1%), in a much shorter time (<3 h) compared to commercial decontamination coatings (similar to 93.8% on stainless steel and similar to 8.4% on cement after 24 h). This performance can be attributed to the strong adhesion and cohesion mediated by catechol moieties. Furthermore, after use, the coating waste is readily dissolvable in acetone, suggesting potential for reducing radioactive waste with the aid of an appropriate separation process, thereby preventing secondary contamination. These results establish CPU as a promising radioactive decontamination strategy.