Independent control of rigidity and toughness of polymeric hydrogels
Independent control of rigidity and toughness of polymeric hydrogels
复制标题
DOI：
10.1021/ma034137w
复制
发表时间：
2003-06-17
期刊：
影响因子：
5.5
通讯作者：
Mooney, DJ
中科院分区：
文献类型：
--
作者：
Kong, HJ;Wong, E;Mooney, DJ
随着水凝胶基材料的应用越来越广泛，对其机械性能的精细控制也越来越多。我们研究了凝胶交联的各个方面，以独立调节弹性模量(E)和韧性M.海藻酸盐水凝胶作为模型体系，因为海藻酸盐可以通过离子或共价交联凝胶化，其块结构决定了离子交联的结构。增加共价交联的密度会增加E，但导致更脆的凝胶。相反，增加离子交联的密度和负责交联的块的长度增加了E和w。振荡剪切测量表明，离子交联及其长度在消散由于部分和逐步去交联引起的变形能量方面很重要。相比之下，共价交联凝胶则经历了能量积累。本研究展示了一种独立控制凝胶不同力学性能的新方法。
Refined control over the mechanical properties of hydrogel-based materials has increased as these materials have found broader application. We investigated various aspects of gel cross-linking to independently regulate the elastic modulus (E) and toughness M. Alginate hydrogels were chosen as a model system, since alginate can be gelled via ionic or covalent cross-linking, and its block structure dictates the structure of ionic cross-links. Increasing the density of covalent cross-links increased E but led to more brittle gels. In contrast, increasing the density of ionic cross-links and length of the blocks responsible for the cross-linking increased both E and W. Oscillatory shear measurements suggested that ionic cross-links and their length were important in dissipating the energy of deformation due to a partial and stepwise de-cross-linking. In contrast, covalently cross-linked gels underwent energy accumulation. This study demonstrates a novel approach to independently control different mechanical properties of gels.