Near-infrared light induced self-healing W18O49/acrylate resin composite coatings with high transparency

Endowing near-infrared light (NIR) induced self-healing coatings with high transparency is an interesting issue with big challenge. Herein, starting from designing an acrylate resin system and surface activated W18O49 nanowires (mW18O49), a new kind of NIR induced self-healing composite coating was developed, which is coded as ACWx (x is the loading of mW18O49 in each coating). The effect of mW18O49 loading on the integrated performance of ACWx coatings was studied. As the content of mW18O49 increases, the transparency of ACWx coatings decreases, but the transmittance at 550 nm of all coatings is still >83.9 %. In addition, ACW0.5 and ACW0.65 composite coatings exhibit outstanding NIR induced self-healing ability after irradiation under NIR (power density of 2.5 W/cm2) for 3 min. Meanwhile, the integrated properties including adhesion, flexibility, hardness, gloss, acid and alkali resistance of ACWx composite coatings meet the application requirements of automotive varnishes.

Automated summary

Developing NIR-induced self-healing composite coatings with high transparency is a challenging issue. This study presents a new type of NIR-induced self-healing composite coating, ACWx, which is prepared using acrylate resin system and surface activated W18O49 nanowires (mW18O49). The loading of mW18O49 affects the transparency of ACWx coatings, but all coatings still exhibit a transmittance of >83.9% at 550 nm. ACW0.5 and ACW0.65 composite coatings demonstrate remarkable NIR-induced self-healing ability and meet the application requirements of automotive varnishes in terms of adhesion, flexibility, hardness, gloss, acid and alkali resistance.