Sheiko Sergei S, Vashahi Foad, Morgan Benjamin J, Maw Mitchell, Dashtimoghadam Erfan, Fahimipour Farahnaz, Jacobs Michael, Keith Andrew N, Vatankhah-Varnosfaderani Mohammad, Dobrynin Andrey V
Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States.
ACS Cent Sci. 2022 Jun 22;8(6):845-852. doi: 10.1021/acscentsci.2c00472. Epub 2022 Jun 9.
Mechanically diverse polymer gels are commonly integrated into biomedical devices, soft robots, and tissue engineering scaffolds to perform distinct yet coordinated functions in wet environments. Such multigel systems are prone to volume fluctuations and shape distortions due to differential swelling driven by osmotic solvent redistribution. Living systems evade these issues by varying proximal tissue stiffness at nearly equal water concentration. However, this feature is challenging to replicate with synthetic gels: any alteration of cross-link density affects both the gel's swellability and mechanical properties. In contrast to the conventional coupling of physical properties, we report a strategy to tune the gel modulus independent of swelling ratio by regulating network strand flexibility with brushlike polymers. Chemically identical gels were constructed with a broad elastic modulus range at a constant solvent fraction by utilizing multidimensional network architectures. The general design-by-architecture framework is universally applicable to both organogels and hydrogels and can be further adapted to different practical applications.
机械性能多样的聚合物凝胶通常被集成到生物医学设备、软体机器人和组织工程支架中，以便在潮湿环境中执行不同但协调的功能。由于渗透溶剂重新分布导致的差异溶胀，这种多凝胶系统容易出现体积波动和形状变形。生物系统通过在几乎相同的水浓度下改变近端组织硬度来避免这些问题。然而，用合成凝胶复制这一特性具有挑战性：交联密度的任何改变都会影响凝胶的溶胀性和机械性能。与传统的物理性能耦合不同，我们报告了一种通过用刷状聚合物调节网络链柔韧性来独立于溶胀率调节凝胶模量的策略。通过利用多维网络结构，在恒定溶剂分数下构建了具有广泛弹性模量范围的化学性质相同的凝胶。通用的按结构设计框架普遍适用于有机凝胶和水凝胶，并且可以进一步适用于不同的实际应用。
