Bio-inspired micro-patterning for tunable, switchable and selective adhesion

Abstract of the related article: Achieving adhesion under unfavourable conditions, such as when van der Waals interaction is not available or in durst environments, is crucial in a number of applications, ranging from surgical sutures to wound-healing tapes, underwater adhesives, robotic grippers, and space grasping. Interestingly, plants, animals, and microorganisms such as mosquitoes, parasites, and plant diaspore, living in similar environmental conditions, show surface morphological traits optimised to achieve mechanical interlocking. Thus, they achieve an effective work of adhesion thanks to the interplay of friction and interfacially-storeable elastic energy, which otherwise typically suppress adhesion. In this work, we provide the design and fabrication fundamentals for achieving tailorable and robust mechanical adhesion, even switchable, effective under a general environmental condition, such as wet or dusty, bio-mimicking natural solutions. A theoretical framework for the design of mechanical adhesion, based on mean field continuum contact mechanics, is suggested, together with a facile micro-fabrication process. This study can pave the way for the development of new technologies, to be employed in situations where conventional adhesives may be ineffective, such as for surfaces exposed to water, solvent vapors, lubricants, high temperatures, dusty environments, high vacuum, or aerospace applications, or processes where switching and selective adhesion is needed such as grasping and sorting applications in semiconductor industry. The files are named after the numbering of the Figure in which they are used.相关研究论文摘要：在范德华相互作用（van der Waals interaction）缺失或多尘环境等不利条件下实现粘附，在诸多应用场景中至关重要，涵盖外科缝合线、伤口愈合胶带、水下胶粘剂、机器人夹持器以及太空抓取作业。有趣的是，生活在类似环境条件下的植物、动物及微生物（如蚊子、寄生虫与植物传播体（plant diaspore）），其表面形貌特征经过优化，可实现机械互锁。因此，它们借助摩擦力与界面可存储弹性能的协同作用，达成高效粘附功——而常规情况下这两种效应通常会抑制粘附。本研究提出了可定制且稳定的机械粘附设计与制造基础，甚至可实现可切换的粘附效果，在潮湿、多尘等通用环境条件下均可有效发挥作用，仿生自然解决方案。本研究基于平均场连续介质接触力学（mean field continuum contact mechanics），提出了机械粘附设计的理论框架，并配套了简易微制造工艺。本研究可为新技术开发铺平道路，这些技术可应用于传统胶粘剂失效的场景，例如暴露于水、溶剂蒸汽、润滑剂、高温、多尘环境、高真空或航空航天应用的表面，或是需要切换与选择性粘附的工艺场景，如半导体行业中的抓取与分选作业。 文件以其对应使用的图表编号命名。