High-performance anti-fouling coating: Achieving high transparency, durability, and flexibility via epoxy-amine curing with dense cross-linking design

Optical instruments, electronic products, and medical fields urgently require the development of robust and transparent anti-fouling coatings. However, traditional coatings often struggle to balance mechanical properties with anti-fouling performance and may contain components that are detrimental to the environment. A high cross-linking density design helps to enhance the mechanical properties and corrosion resistance of coatings without the use of environmentally unfriendly components. In this work, we prepared a novel polyhedral oligomeric silsesquioxane (POSS) material with multiple epoxy groups, EP-POSS, through a click reaction. We selected an appropriate multi-point amine curing agent, tetraethylenepentamine, leveraging its efficient curing with EP-POSS to construct a multi-point, highly cross-linked network. This process not only strengthens the mechanical strength and chemical resistance of the coating but is also simple and cost-effective. Environmentally friendly polydimethylsiloxane is used to provide flexibility and liquid repellency. The final EPOSSPT coating boasts high transparency (> 99%), low surface roughness (arithmetic mean deviation (Sa): ∼0.515 nm), and excellent repulsion to both liquid and solid contaminants, demonstrating superior self-cleaning and anti-fouling properties. It achieves a balance between high hardness (7H) and excellent flexibility (7500 bending cycles with a bending radius of 1 mm), while also resisting wear and impact from everyday use. This high-transparency, robust, and flexible coating has broad application prospects and offers insights into the design of new high-performance protective materials.