可再生仿生微结构抗粘附材料的设计与制备

Deposition and adhesion of unwanted foreign materials on surfaces are ubiquitous and often problematic in our daily life, as well as in almost all industry sectors. The preparation of current bio-inspired or bio-mimicking anti-adhesion materials, such as superlyophobic surfaces and liquid-infused materials, usually relies on the construction of micro-structures to confine air pockets or liquid layer. On the one hand, the stability of air pockets and liquid layers is not satisfactory; on the other hand, the surface structures are easily destroyed. Inspired by the lifetime-long anti-adhesion performance of land plant leaves, which rely on the regenerability of the epicuticular wax structure as well as the solid feature of the surface wax layer, this project will start from understanding the structure formation principle and anti-adhesion mechanism of epicuticular wax layer, design and prepare bio-inspired anti-adhesion materials with regenerable micro-structures by swelling molten wax into crosslinked polymer elastomer. Swelling behavior of wax molecules in polymer networks, phase separation between wax and polymer, and diffusing of wax molecules in polymer networks will be investigated. Furthermore, formation and growth of wax crystals on the surface will be studied in order to achieve the self-construction of bio-mimicking structure as well as self-healing anti-adhesion functionality of the anti-adhesion material. In addition, potential application of the anti-adhesion materials in liquid-repellent, anti-icing, and anti-fouling will be discussed.

目前，仿生超疏抗粘附材料和液体层抗粘附材料的制备需借助外部加工手段来构建表面微观结构束缚空气层或液体层，空气层或液体层的稳定性较差，且微结构受损后无法自修复，因此限制了上述材料的发展。本项目拟学习陆生植物抗粘附表面固体表皮蜡层微结构的形成与作用机制，利用聚合物交联网络具有自由体积的特点，采用熔融的小分子固体蜡类物质对交联的高分子弹性体进行溶胀，制备具有固体表层的有机凝胶材料。通过研究小分子蜡类物质在高分子交联网络中的溶胀行为、相分离特征、扩散释放动力学、以及在表面的结晶生长过程等涵盖的基本科学问题，对小分子蜡在材料表面的晶体结构进行调控，实现表面微结构的自主构建与可再生，设计制备具有与天然表面类似微结构的仿生抗粘附材料。基于表面结构的可再生实现抗粘附功能的自修复，并进行疏液、抗污、防冰等抗粘附应用研究。进而丰富结构仿生和功能仿生理论体系，为仿生抗粘附材料的优化设计与实际应用提供支撑。

目前，仿生超疏抗粘附材料和液体层抗粘附材料的制备需借助外部加工手段来构建表面微观结构束缚空气层或液体层，空气层或液体层的稳定性较差，且微结构受损后无法自修复，因此限制了上述材料的发展。本项目学习陆生植物抗粘附表面固体表皮蜡层微结构的形成与作用机制，利用聚合物交联网络具有自由体积的特点，采用熔融的小分子固体蜡类物质对交联的高分子弹性体进行溶胀，制备了具有固体表层的仿生有机凝胶材料。通过研究小分子蜡类物质在高分子交联网络中的溶胀行为、相分离特征、扩散释放动力学、以及在表面的结晶生长过程等涵盖的基本科学问题，对小分子蜡在材料表面的晶体结构进行调控，实现表面微结构的自主构建与可再生，设计制备了具有与天然表面类似微结构的仿生抗粘附材料，基于表面结构的可再生实现了超疏水功能和抗粘附功能的自修复。本项目研究丰富了结构仿生和功能仿生理论体系，为仿生抗粘附材料的优化设计与实际应用提供了实验支撑。