Wu Jianzhen, Wu Xiuzhicheng, Yang Fujian, Liu Xiaonan, Meng Fanjun, Ma Qinglin, Che Yuju
Marine College, Shandong University (Weihai), Wenhua West Rd., Weihai, Shandong Province, 264209, PR China.
Marine College, Shandong University (Weihai), Wenhua West Rd., Weihai, Shandong Province, 264209, PR China.
Int J Biol Macromol. 2023 Jan 15;225:1119-1128. doi: 10.1016/j.ijbiomac.2022.11.173. Epub 2022 Nov 19.
Building multiple chemical crosslinks is an effective strategy to improve mechanical properties and to diversify final application of polysaccharide nanoparticles reinforced poly(vinyl alcohol) (PVA) physical hydrogels. In this work, PVA/cellulose nanofibers (CNFs) were used as composite substrate to fabricate ionic conductive hydrogels for strain sensor. Three types of characteristic crosslinks, including chemical crosslinking via boronic ester covalent bonds only, and with additional metal coordination bonding, as well as coexistence of physical crosslinks via PVA crystallites and aforementioned two kinds of chemical crosslinks, were constructed. The sample with triple crosslinks has superior mechanical strength and resistance to fatigue, and the polydopamine/Fe ratio act as key to tune final performance because double-network structure prefers to form as Fe is superfluous, while dual-crosslink one forms in the case of insufficient Fe. As-optimized ionic conductive hydrogel is suitable as strain sensor for probing human motions. This work provides an interesting insight into the network structure and property regulation for PVA/CNF composite hydrogels with multiple crosslinks.
构建多个化学交联是改善多糖纳米颗粒增强聚乙烯醇（PVA）物理水凝胶的机械性能并使其最终应用多样化的有效策略。在这项工作中，PVA/纤维素纳米纤维（CNF）被用作复合基材来制备用于应变传感器的离子导电水凝胶。构建了三种类型的特征交联，包括仅通过硼酸酯共价键的化学交联、额外的金属配位键交联，以及通过PVA微晶的物理交联与上述两种化学交联的共存。具有三重交联的样品具有优异的机械强度和抗疲劳性，聚多巴胺/铁的比例是调节最终性能的关键，因为当铁过量时倾向于形成双网络结构，而在铁不足的情况下形成双交联结构。优化后的离子导电水凝胶适合作为探测人体运动的应变传感器。这项工作为具有多个交联的PVA/CNF复合水凝胶的网络结构和性能调控提供了有趣的见解。
