基于两性离子聚乙烯亚胺功能化镓纳米液滴的自修复聚二甲基硅氧烷防污涂料

There is an urgent need to develop effective and eco-friendly nanostructured coatings for marine antifouling to replace traditional coatings, while ensuring they do not lead to environmental hazards. Gallium-based liquid metal (GLM), which has unique antibacterial and non-toxic properties, has potential for applications in antifouling. In this study, GLM nanodroplets modified with zwitterionic polymer (polyethylenimine-quaternized derivative, PEIS) based antifouling agent were prepared successfully via sonication and Michael-addition, which could potentially be incorporated into the polydimethylsiloxane coating (PDMS) as a functional filler. A series of characterization methods, such as infrared spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy, have proved the successful modification of GLM nanodroplets with PEIS. The PEIS functionalized GLM nanodroplets exhibit good anti-bacterial properties due to synergistic bactericidal activity of Ga 3+ stemming from GLM nanodroplets and the quaternary ammonium group from zwitterionic polymer PEIS. The synergistic anti-bacterial properties of PEIS-GLM nanodroplets and strong surface hydration of zwitterionic polymer PEIS result in remarkable antifouling performance of the filler. Subsequently, through the observation of the cross section, the as-prepared PEIS modified GLM nanodroplets exhibit good dispersibility in the PDMS coating, which also ensures that the PEIS-GLM@PDMS coating has satisfactory antifouling effect (removal of above 90% bacteria and 70% microalgae). Furthermore, the PEIS modified GLM nanodroplets endow the PDMS coating with self-healing properties by reason of the crosslinking of unreacted vinyl in PDMS by exposed GLM initiating polymerization under external mechanical force.