Interaction mechanisms between organic and inorganic phases in calcium silicate hydrates/poly(vinyl alcohol) composites
Interaction mechanisms between organic and inorganic phases in calcium silicate hydrates/poly(vinyl alcohol) composites
复制标题
DOI：
10.1016/j.cemconres.2019.105891
复制
发表时间：
2019-11
影响因子：
11.4
通讯作者：
Yang Zhou;L. Tang;Jiaping Liu;C. Miao
中科院分区：
文献类型：
--
作者：
Yang Zhou;L. Tang;Jiaping Liu;C. Miao
聚乙烯醇（PVA）乳液常用于水泥基材料以获得更高的性能。本文采用常压和高压X射线衍射（XRD）、29 Si魔角旋转核磁共振（MAS NMR）、纳米压痕和分子动力学模拟研究了PVA与水化硅酸钙（C-S-H）的相互作用机理。在C-S-H纳米颗粒中，小尺寸的PVA分子可以插入到硅酸钙片的层间区域中，从而降低层间不可压缩性和C-S-H在晶体长度尺度上的总体积模量。在较大的长度尺度下，大尺寸的PVA链可以处于C-S-H纳米颗粒之间，降低孔隙率，从而提高介观复合材料的压痕模量。
Poly (vinyl alcohol) (PVA) emulsion is commonly used in cement-based materials to obtain higher performance. The present work investigates the interaction mechanisms between PVA and calcium silicate hydrates (C-S-H) using ambient and high pressure X-ray diffraction (XRD),29Si magic angle spinning nuclear magnetic resonance (MAS NMR), nano-indentation, and molecular dynamics simulation. In a C-S-H nano-particle, small-size PVA molecules can be intercalated into the interlayer region of the calcium silicate sheets, lowering the interlayer incompressibility and the overall bulk modulus of C-S-H at the crystal length scale. At a larger length scale, the large-size PVA chains can be in the midst among the C-S-H nano-particles, decreasing the porosity, thus the indentation modulus of the meso-composite is improved.