CAREER: Robust, Reversible, and Stimuli-responsive Thermodynamic Adhesion in Hydrogels

事业：水凝胶中稳健、可逆且刺激响应的热力学粘附

• 批准号: 2337592
• 负责人: Qihan Liu
• 金额: $ 54.61万
• 依托单位: University of Pittsburgh
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-05-01 至 2029-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2337592&HistoricalAwards=false
• 关键词: CAREER; Robust; Reversible; Stimuli; responsive

This Faculty Early Career Development (CAREER) grant will support research that investigates a new type of hydrogel adhesion mechanism that can be switched on and off using external stimuli. Hydrogels are soft and hydrated materials similar to our body tissues. This similarity makes them useful for creating soft machines that better interact with human bodies. Applications of soft machines include medical implants, wearable devices, and biomimetic robots. Unlike conventional machines that are assembled by rigid parts like nuts and bolts, soft machines are assembled through deformable adhesion. Although some existing studies have realized hydrogel adhesion that can reliably survive larger deformation, it is difficult to reversibly switch the adhesion on and off so that the soft machine can be repaired or reconfigured by part exchange, which is a common practice in conventional machines. This project will investigate novel adhesion mechanisms that enable the reversible assembly of soft machines. The success of the project will revolutionize the design of soft machines, which in turn will impact the development of many relevant applications. Moreover, the project will create training materials to help graduate students turn cutting-edge research findings into short, easy-to-understand videos. These videos, when shared on free online platforms, can bring the latest research to a much wider and diverse audience than is possible through traditional academic journals and seminars.The project aims to realize switchable adhesions through stimuli-responsive osmocapillary and electrostatic interactions on hydrogel interfaces. While stimuli-responsive adhesion based on these mechanisms has been reported for some material-stimulus systems, the mechanics governing these mechanisms is understudied. This project will explore the underlying mechanics by (1) characterizing the adhesion under controlled thermodynamic states, thus establishing the thermodynamic constitutive relations of osmocapillary and electrostatic adhesion, (2) characterizing the adhesion with controlled bulk dissipation and performing finite element simulations to study the coupling between interfacial interactions and bulk dissipation, and (3) modeling time-dependent adhesion using established hydrogel field theories and validating the model with experiments. The outcome of the project will significantly deepen the understanding of osmocapillary and electrostatic interactions on hydrogel interfaces and will pave the way for designing reversible adhesion with customizable stimuli-responsive switching behaviors.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

该教师早期职业发展（CAREER）拨款将支持研究一种新型水凝胶粘附机制，该机制可以使用外部刺激打开和关闭。水凝胶是类似于我们身体组织的柔软且水合的材料。这种相似性使得它们可用于创建能够更好地与人体互动的软机器。软机器的应用包括医疗植入物、可穿戴设备和仿生机器人。与由螺母和螺栓等刚性部件组装的传统机器不同，软机器是通过可变形粘合来组装的。尽管一些现有的研究已经实现了水凝胶粘附能够可靠地承受较大的变形，但很难可逆地打开和关闭粘附，以便通过零件更换来修复或重新配置软机器，这是传统机器中的常见做法。该项目将研究能够实现软机器可逆组装的新型粘合机制。该项目的成功将彻底改变软机器的设计，进而影响许多相关应用的开发。此外，该项目还将制作培训材料，帮助研究生将前沿研究成果转化为简短易懂的视频。这些视频在免费的在线平台上分享时，可以将最新研究成果带给比传统学术期刊和研讨会更广泛和多样化的受众。该项目旨在通过水凝胶界面上的刺激响应渗透毛细管和静电相互作用来实现可切换的粘附。虽然已经报道了一些材料刺激系统基于这些机制的刺激响应粘附，但控制这些机制的力学尚未得到充分研究。该项目将通过以下方式探索潜在的力学：（1）表征受控热力学状态下的粘附，从而建立渗透毛细管和静电粘附的热力学本构关系，（2）表征受控体耗散的粘附并进行有限元模拟以研究耦合界面相互作用和体积耗散之间的关系，以及（3）使用已建立的水凝胶场理论对时间依赖性粘附进行建模并通过实验验证模型。该项目的成果将显着加深对水凝胶界面上渗透毛细管和静电相互作用的理解，并将为设计具有可定制刺激响应切换行为的可逆粘附铺平道路。该奖项反映了 NSF 的法定使命，并通过评估被认为值得支持利用基金会的智力优势和更广泛的影响审查标准。