具有优异自恢复性能的高强度聚电解质复合物水凝胶  

Polyelectrolyte Complexes-based Hydrogels with High Mechanical Strength and Excellent Self-recovery

作　　者：袁涛 孙俊奇[1] Tao Yuan;Jun-qi Sun(State Key Laboratory of Supramolecular Structure and Materials,College of Chemistry,Jilin University,Changchun 130012)

机构地区：[1]超分子结构与材料国家重点实验室吉林大学化学学院

出　　处：《高分子学报》2019年第12期1263-1271,共9页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号21774049)资助项目

摘　　要：具有高力学强度和优异自恢复性能的水凝胶在组织工程、可拉伸电子器件及可穿戴设备等领域具有潜在的应用价值.本工作通过将4-甲酰苯-1,3-二磺酸修饰的聚乙烯醇(SPVA)与线形聚乙烯亚胺(LPEI)在水溶液中复合,并经过塑形、干燥和水浸泡过程,制备了具有优异自恢复性能的高强度聚电解质复合物水凝胶.凝胶中强的静电作用和弱的氢键作用的协同作用使该水凝胶具有高的断裂强度和韧性,其断裂强度和韧性可达~10.0 MPa和~14.21 MJ/m^3.该水凝胶被拉伸到200%后,室温下不需要任何外界刺激,在1 h内就可完全恢复其初始形状和力学性能.Polymeric hydrogels with high mechanical strength and excellent self-recovery are useful in tissue engineering, stretchable electronics and wearable devices. In this work, polyelectrolyte complexes-based hydrogels with high mechanical strength and excellent self-recovery are fabricated by complexation of poly(vinyl alcohol) modified with benzaldehyde-2,4-disulfonic acid disodium salt(BADS)(denoted as SPVA) with linear poly(ethylenimine)(LPEI) in aqueous solution followed by molding, drying and rehydration. The mechanical properties of the LPEIa/x%-SPVAb hydrogels, where x% represents the molar ratio of BADS to the monomer molar ratio of PVA, and a and b represent the feed mass ratio of LPEI to SPVA, can be well-tailored by varying the parameters such as the grafting ratio of BADS on SPVA and mass ratio of LPEI to SPVA. Stress-strain measurements indicate that the LPEI1/18%-SPVA1 hydrogels have the highest mechanical strength, with a tensile strength of ~ 10.0 MPa and a toughness of ~ 14.21 MJ/m^3. A piece of the LPEI1/18%-SPVA1 hydrogel strip with a width of 2 mm and thickness of 2 mm can sequentially withstand various deformations such as bending, knotting,and twisting, and can lift a 1 kg weight without any damage. Besides the electrostatic interactions between sulfonate groups of SPVA and protonated amine groups of LPEI, Fourier transform infrared spectroscopy confirms the existence of hydrogen-bonding interactions between hydroxyl and sulfonate groups on SPVA. The synergy of strong electrostatic interactions and weak hydrogen-bonding interactions endows the hydrogels with high mechanical strength and toughness. Moreover, the hydrogels can completely recover from a strain of 200% to their original shape and mechanical properties within 1 h rest at room temperature without any external assistance.The excellent self-recovery of the LPEI1/18%-SPVA1 hydrogels originates from the high elastic retraction of polymer chains arising from electrostatic interactions and the reversibility of sacrificial hydrogen-bonding i

关 键 词：水凝胶 聚电解质 聚电解质复合物 自恢复性能 

分 类 号：TQ427.26[化学工程]