中文摘要：

通过溶液沉淀法制备了初始钙硅比为1.0～1.7的掺杂PVA的水化硅酸钙（C–S–H-PVA）系列样品，研究了C–S–H-PVA的纳米结构特征。结果表明：PVA的加入增加了C–S–H的层间距，影响了C–S–H的层间结构；C–S–H-PVA样品的Fourier 变换红外光谱中出现了CH2/CH伸缩振动峰，29Si 核磁共振（NMR）谱中出现了1个Q1峰和2个Q2峰，而且PVA的加入使Q1、Q2峰向更负方向偏移，使Q2/Q1的比值以及硅酸盐链的平均链长（MCL）增长，说明PVA能增加C–S–H结构中的硅氧四面体聚合度。随着钙硅比的增加，C–S–H-PVA样品的29Si NMR谱中Q1、Q2峰的化学位移向正方向偏移，Q2/Q1的比值以及MCL减小，这一变化规律与未掺PVA的C–S–H样品的变化规律类似。

英文摘要：

Calcium silicate hydrate-polyvinyl alcohol （PVA） composites （C–S–H-PVA） with C/S 1.0–1.7 were prepared via precipitation in solution. The nanostructural characteristics were investigated. The layered stacking of C–S–H was disturbed and its interlayer spacing was increased in the presence of PVA. The additional peaks attributed to CH2 or CH stretch could be detected via the Fourier transform infrared spectra of the C–S–H-PVA. The 29Si nuclear magnetic resonance （NMR） spectra of C–S–H-PVA revealed one Q1 peak and two Q2 peaks. The chemical shifts of the peaks shifted to more negative, Q2/Q1 and mean chain length （MCL） increased in the presence of PVA, indicating that the incorporation of PVA increased the polymerization of the silica tetrahedra. As the C/S ratios of C–S–H-PVA increased, the chemical shifts of the peaks shifted to less negative, Q2/Q1 and MCL decreased, which was similar to the results of C–S–H without PVA.