Department of Materials Science and Engineering, Stanford University, Stanford, CA, 94305, USA.
Department of Hybrid Polymeric Materials, IBM Almaden Research Center, San Jose, CA, 95120, USA.
Nat Commun. 2017 Oct 18;8(1):1019. doi: 10.1038/s41467-017-01305-w.
Hyperconnected network architectures can endow nanomaterials with remarkable mechanical properties that are fundamentally controlled by designing connectivity into the intrinsic molecular structure. For hybrid organic-inorganic nanomaterials, here we show that by using 1,3,5 silyl benzene precursors, the connectivity of a silicon atom within the network extends beyond its chemical coordination number, resulting in a hyperconnected network with exceptional elastic stiffness, higher than that of fully dense silica. The exceptional intrinsic stiffness of these hyperconnected glass networks is demonstrated with molecular dynamics models and these model predictions are calibrated through the synthesis and characterization of an intrinsically porous hybrid glass processed from 1,3,5(triethoxysilyl)benzene. The proposed molecular design strategy applies to any materials system wherein the mechanical properties are controlled by the underlying network connectivity.
超交联网络结构可以赋予纳米材料显著的机械性能,这些性能从根本上可以通过将连接性设计到内在的分子结构中进行控制。对于混合有机-无机纳米材料,在这里我们表明,通过使用 1,3,5-三乙氧基硅基苯前体,网络中硅原子的连接性超出了其化学配位数,从而形成了具有异常弹性刚度的超交联网络,高于完全致密的二氧化硅。通过分子动力学模型证明了这些超交联玻璃网络的优异固有刚度,并且通过合成和表征由 1,3,5-(三乙氧基硅基)苯处理的固有多孔混合玻璃来对这些模型预测进行校准。所提出的分子设计策略适用于任何机械性能受基础网络连接性控制的材料体系。