Thermally induced reversible and reprogrammable actuation of tough hydrogels utilising ionoprinting and iron coordination chemistry

SENSORS AND ACTUATORS B-CHEMICAL

卷:254

Article

Baker, Anna B.^1,2  Wass, Duncan F.³  Trask, Richard S.¹ 

[1] Univ Bath, Dept Mech Engn, Bath BA2 7AY, Avon, England

[2] Univ Bristol, Dept Aerosp Engn, ACCIS, Bristol BS8 1TR, Avon, England

[3] Univ Bristol, Sch Chem, Bristol BS8 1TS, Avon, England

关键词: Ionoprinting;    Hydrogel;    Interpenetrating polymer network;    Actuation;    Temperature responsive;   

DOI  :  10.1016/j.snb.2017.07.095

来源: Elsevier

【 摘 要 】

Ionoprinting has proven itself as a technique capable of enabling repeated post-synthesis programming of hydrogels into a variety of different shapes, achieved through a variety of different actuation pathways. To date, the technique of ionoprinting has been limited to conventional brittle hydrogels, with reversible actuation requiring a change in submersion solution. In this study, ionoprinting has been combined for the first time with a tougher interpenetrating network polymer (IPN) hydrogel with dual pH and temperature responsiveness. This new methodology eliminates the brittle material failure typically occurring during shape change programming and actuation in hydrogels, thus allowing for the realisation of more highly strained and complex shape formation than previously demonstrated. Critically, the temperature responsiveness of this system enables actuation between an unfolded (2D) and a folded (3D) shape through an external stimuli; enabling reversible actuation without a change in submersion solution. Here, the reversible thermally induced actuation is demonstrated for the first time through the formation of complex multi-folded architectures, including an origami crane bird and Miura folds, from flat hydrogel sheets. The robustness of the IPN hydrogel is demonstrated through multiple reprogramming cycles and repeated actuation of a single hydrogel sheet formed into 3D shapes (hexagon, helix and zig-zag). These advancements vastly improve the applicability of ionoprinting extending its application into areas of soft robotics, biomedical engineering and enviro intelligent sensors. (C) 2017 The Authors. Published by Elsevier B.V.

【 授权许可】

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