Judiciously designed dual cross-linked networks for highly transparency, robustness and flexibility in liquid-repellent coatings

Abstract

Highly transparent, durable, and flexible liquid-repellent coatings are urgently needed in the realm of transparent materials, such as car windows, optical lenses, solar panels, and flexible screen materials. However, it has been difficult to strike a balance between the robustness and flexibility of coatings constructed by a single cross-linked network design. To overcome the conundrum, this innovative approach effectively combines two distinct cross-linked networks with unique functions, thus overcoming the challenge. Through a tightly interwoven structure comprised of added crosslinking sites, the coating achieves improved liquid repellency (WCA>100°, OSA<10°), increased durability (withstands 2,000 cycles of cotton wear), enhanced flexibility (endures 5,000 cycles of bending with a bending radius of 1 mm), and maintains high transparency (over 98 % in the range of 410 nm to 760 nm). Additionally, the coating with remarkable adhesion can be applied to multiple substrates, enabling large-scale preparation and easy cycling coating, thus expanding its potential applications. The architecture of this fluoride-free dual cross-linked network not only advances liquid-repellent surfaces but also provides valuable insights for the development of eco-friendly materials in the future.