Mohanan Vaisakh Vilavinalthundil, Mak Ho Yi Lydia, Gurung Nishan, Xu Qin
Department of Physics, Faculty of Sciences, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong SAR, China.
Department of Geoscience and Remote Sensing, Faculty of Civil Engineering and Geosciences, Delft University of Technology, 2628 CN Delft, The Netherlands.
Materials (Basel). 2022 Jan 23;15(3):852. doi: 10.3390/ma15030852.
Soft polymeric gels are susceptible to buckling-induced instabilities due to their great compliance to surface deformations. The instability patterns at soft interfaces have great potential in engineering functional materials with unique surface properties. In this work, we systematically investigated how swelling-induced instability patterns effectively improved the adhesive properties of soft polydimethylsiloxane (PDMS) gels. We directly imaged the formations of the surface instability features during the relaxation process of a swollen gel substrate. The features were found to greatly increase the adhesion energy of soft gels across multiple length scales, and the adhesion enhancement was associated with the variations of contact lines both inside the contact region and along the contact periphery. We expect that these studies of instability patterns due to swelling will further benefit the design of functional interfaces in various engineering applications.
柔软的聚合物凝胶由于对表面变形具有很大的柔顺性，容易受到屈曲诱导的不稳定性影响。软界面处的不稳定性模式在设计具有独特表面性质的功能材料方面具有巨大潜力。在这项工作中，我们系统地研究了溶胀诱导的不稳定性模式如何有效地改善软聚二甲基硅氧烷（PDMS）凝胶的粘附性能。我们直接成像了溶胀凝胶基质松弛过程中表面不稳定性特征的形成。发现这些特征在多个长度尺度上极大地增加了软凝胶的粘附能，并且粘附增强与接触区域内和接触周边的接触线变化有关。我们期望这些关于溶胀引起的不稳定性模式的研究将进一步有益于各种工程应用中功能界面的设计。
