Hierarchical Toughening of a Biomimetic Bulk Cement Composite

• DOI: 10.1021/acsami.0c15313
• Publication Date: 2020-11-10T20:53:33Z
• Authors: Hao Pan; Wei She; Wenqiang Zuo; Yang Zhou; Jiale Huang; Zhongwen Zhang; Zifan Geng; Yiming Yao; Wenhua Zhang; Li Zheng; Changwen Miao; Jiaping Liu
• Keywords: cement; structure design; polymer; biomimetic composite; 0211 other engineering and technologies; /dk/atira/pure/subjectarea/asjc/2500/2500; 02 engineering and technology; name=General Materials Science; 0210 nano-technology; hierarchical toughening; 620

Because of the inherent quasibrittleness and heterogeneity, matrix-directed toughening of concrete and cement composites remains to be a huge challenge. Herein, inspired by nacre materials, a novel biomimetic bulk cement composite is fabricated via a facile and efficient process based on compacting prefabricated multisized cement-polymer hybrid prills. This method combines with the three-dimensional "brick-bridge-mortar" structure design and synchronously the intrinsic and extrinsic toughening strategies. Such an approach shows the remarkable maximum toughness enhancement of 27-fold with 71% increase in flexural strength via cooperation with only 4 wt % organic matter. More attractively, it alters the traditional brittle fracture of cement composites to a distinct ductile fracture. In addition, such a biomimetic composite demonstrates the long-term ever-increasing strength and toughness, performing the excellent ductile-fracture retention ability. The hierarchical toughening mechanisms are further revealed with the synergy of microscopic characterizations and simulation methods. This strategy provides a new route for the development of high toughness biomimetic cement-based materials for potential applications in civil engineering domain.