Cixi Institute of Biomedical Engineering & Polymers and Composites Division, Ningbo Institute of Materials Technology & Engineering, Chinese Academy of Sciences , 1219 Zhongguan West Road, Ningbo 315201, China.
Faculty of Materials Science and Chemical Engineering, Ningbo University , Ningbo, 315211, China.
ACS Appl Mater Interfaces. 2016 Oct 5;8(39):26326-26331. doi: 10.1021/acsami.6b08841. Epub 2016 Sep 20.
Multiresponsive polyelectrolyte hydrogels with extraordinary toughness have great potential in soft device applications. Previously we have demonstrated a series of tough and multiresponsive hydrogels by using multifunctional triblock copolymer (Pluronic F127 diacrylate, F127DA) micelles to cross-link cationic polyelectrolyte chains into 3D network. Herein, we further synthesize negatively charged hydrogels comprising 2-acrylamido-2-methyl propylsulfonic acid (AMPS) monomers by using F127DA micelles as cross-linkers. Similar to the positive nanomicelle (NM) hydrogels, the negative NM hydrogels exhibited a compressive strength up to 59 MPa with a fracture strain up to 98%, and tensile fracture strain higher than 2000%. These charged hydrogels were actuated by electric field when immersed in salt solutions. The effects of electrolyte concentration, electric field strength, and ionic monomer content on the electric actuation behavior of these electroactive hydrogels (EAHs) have been systematically investigated. It is concluded that the electroactive hydrogels show a fast actuation rate with a bending angle up to 87° at 120 s and the bending angle was cyclically reversed upon changing bias direction without a large decrease. This study demonstrates that such tough and multiresponsive electroactive hydrogels may have great potential in sensors, actuators, switches, and artificial muscles.
具有非凡韧性的多重响应聚电解质水凝胶在软设备应用中有很大的潜力。以前，我们已经通过使用多功能两亲嵌段共聚物（Pluronic F127 二丙烯酸酯，F127DA）胶束交联阳离子聚电解质链来制备一系列坚韧且多重响应的水凝胶，从而展示了这一潜力。在此，我们进一步通过 F127DA 胶束作为交联剂合成了包含 2-丙烯酰胺基-2-甲基丙磺酸（AMPS）单体的负电荷水凝胶。与正纳米胶束（NM）水凝胶类似，负 NM 水凝胶表现出高达 59 MPa 的压缩强度和高达 98%的断裂应变，拉伸断裂应变高于 2000%。这些带电荷的水凝胶在浸入盐溶液时可以通过电场进行驱动。系统研究了电解质浓度、电场强度和离子单体含量对这些电活性水凝胶（EAHs）的电致动行为的影响。结论是，电活性水凝胶表现出快速的致动速率，在 120 秒时达到 87°的弯曲角度，并且在改变偏置方向时，弯曲角度可以循环反转，而没有明显的下降。这项研究表明，这种坚韧且多重响应的电活性水凝胶在传感器、执行器、开关和人造肌肉方面可能具有巨大的潜力。
