Mimicking Dynamic Adhesiveness and Strain-Stiffening Behavior of Biological Tissues in Tough and Self-Healable Cellulose Nanocomposite Hydrogels
Mimicking Dynamic Adhesiveness and Strain-Stiffening Behavior of Biological Tissues in Tough and Self-Healable Cellulose Nanocomposite Hydrogels
复制标题
在坚韧且可自修复的纤维素纳米复合水凝胶中模拟生物组织的动态粘附性和应变硬化行为
DOI：
10.1021/acsami.8b21588
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发表时间：
2019-02-13
影响因子：
9.5
通讯作者：
Yang, Jun
中科院分区：
文献类型：
--
作者：
Shao, Changyou;Meng, Lei;Yang, Jun
自修复凝胶具有与生物组织相似的结构，在生物医学领域引起了广泛的关注，但其快速自修复性能与高机械韧性的结合仍然是一个难题。在动态可逆交联设计的基础上，我们将刚性单宁酸包覆的纤维素凝胶（TA@CNC）的图案到聚乙烯醇（PVA）-聚乙烯醇动态网络的制造高韧性和快速自愈合的纳米复合材料（NC）水凝胶，连同动态粘合和应变硬化性能，是特别是在软组织替代品的实际应用中不可或缺的。结果表明，所制备的NC凝胶呈现出高度互连的网络结构，其中柔性PVA链缠绕在刚性TA@CNC基序上，并形成通过氢键缔合的动态TA@CNC-PVA簇，从而提供临界机械韧性。硼酸酯-二醇键和氢键之间的协同相互作用赋予NC凝胶典型的自愈合行为，允许动态交联网络在秒的时间尺度内进行快速重排。此外，所获得的NC水凝胶不仅模仿生物组织的主要特征与独特的应变硬化行为，但也显示出独特的动态粘附到无孔和多孔基板。该方法为合理设计性能优异的多功能纤维素水凝胶开辟了新的前景，从而拓展了其应用领域。
Although self-healing gels with structural resemblance to biological tissues attract great attention in biomedical fields, it remains a dilemma for combination between fast self-healing properties and high mechanical toughness. On the basis of the design of dynamic reversible cross-links, we incorporate rigid tannic acid-coated cellulose nanocrystal (TA@CNC) motifs into the poly(vinyl alcohol) (PVA)-borax dynamic networks for the fabrication of a high toughness and rapidly self-healing nanocomposite (NC) hydrogel, together with dynamically adhesive and strain-stiffening properties that are particularly indispensable for practical applications in soft tissue substitutes. The results demonstrate that the obtained NC gels present a highly interconnected network, where flexible PVA chains wrap onto the rigid TA@CNC motifs and form the dynamic TA@CNC-PVA clusters associated by hydrogen bonds, affording the critical mechanical toughness. The synergetic interactions between borate-diol bonds and hydrogen bonds impart a typical self-healing behavior into the NC gels, allowing the dynamic cross-linked networks to undergo fast rearrangement in the time scale of seconds. Moreover, the obtained NC hydrogels not only mimic the main feature of biological tissues with the unique strain-stiffening behavior but also display unique dynamic adhesiveness to nonporous and porous substrates. It is expected that this versatile approach opens up a new prospect for the rational design of multifunctional cellulosic hydrogels with remarkable performance to expand their applications.