Reusable Antifouling Viscoelastic Adhesive with an Elastic Skin

Abstract

Although the viscoelasticity or tackiness of a pressure-sensitive adhesive gives it strength owing to energy dissipation during peeling, it also renders it nonreusable because of structural changes such as the formation of fibrils, cohesive failure, and fouling. However, an elastic layer has good structural integrity and cohesive strength but low adhesive energy. We demonstrate an effective composite adhesive in which a soft viscoelastic bulk layer is imbedded in a largely elastic thin skin layer. The composite layer is able to meet the conflicting demands of the high peel strength comparable to the viscoelastic core and the structural integrity, reusability, and antifouling properties of the elastic skin. Our model adhesive is made of poly(dimethylsiloxane), where its core and skin are created by varying the cross-linking percentage from 2 to 10%.

Coupled effects of applied load and surface structure on the viscous forces during peeling

“…We see that for all loading conditions and samples, the measured forces display the same qualitative features: the forces rise rapidly, reach a peak, and drop abruptly. These general features are qualitatively similar to the ones observed for other peeling 29,50 and normal force measurements 44,51 in viscous fluids with smooth surfaces. In the force curves, the position and magnitude of the peak forces are instrument specific and characteristic of the load cell employed.…”

Switchable Photonic Bio‐Adhesive Materials

“…Color in nature visualizes the internal state under diverse chemical and physical triggers [1,2] and provided great inspiration for bio-inspired switchable adhesives. [3] Modern synthetic adhesive materials can be applied to variety of surfaces, from hard structural components to soft biological tissues but unsticking without damage remains a critical issue [4][5][6][7][8] in a variety of applications ranging from wound dressings to soft robotics. [8][9][10][11][12][13][14][15][16][17] Adhesive performance cannot be continuously monitored via quick visual means [17,18] and the monitoring of hidden interfaces (e.g., wound healing) is impossible due to the masking nature of materials explored.…”

High Capacity, Easy Release Adhesives From Renewable Materials

“…These processes increase the energy required to separate the interface requiring higher forces when separating, which reduces releasability; thus PSAs gain adhesive force capacity at the expense of easy release. “Tacky” PSAs are also inherently non‐reusable as they easily foul and the inelastic processes can permanently deform the physical structure of the adhesive . Additionally, their renewable content is typically below 100% because of the limited availability of natural raw materials and additives, such as tackifying agents, which are necessary for performance .…”