使用动态光散射法研究胶体纳米二氧化硅在超高性能混凝土环境中的行为。

Behavior of Colloidal Nanosilica in an Ultrahigh Performance Concrete Environment Using Dynamic Light Scattering.

作者信息

Hendrix Douglas, McKeon Jessica, Wille Kay

机构信息

Department of Materials Science and Engineering, University of Connecticut, Storrs, CT 06269, USA.

Department of Chemistry, University of Connecticut, Storrs, CT 06269, USA.

出版信息

Materials (Basel). 2019 Jun 19;12(12):1976. doi: 10.3390/ma12121976.

DOI:10.3390/ma12121976

PMID:31248136

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC6631289/

Abstract

The dispersion quality of nanosilica (NS) is an essential parameter to influence and control the material characteristics of nanosilica-enhanced concrete. In this research, the dispersion quality of colloidal nanosilica in simulated concrete environments was investigated using dynamic light scattering. A concrete environment was simulated by creating a synthetic pore solution that mimicked the ionic concentration and pH value of ultrahigh-performance concrete in the fluid state. Four colloidal nanosilica samples were used, ranging in particle sizes from 5 to 75 nm, with differing solid contents and stabilizing ions. It was found that the sodium stabilized 20 nm NS sol remains dispersed at a solid concentration of 2 wt % through a variety of pH values with the inclusion of potassium ions. Calcium ions are a major contributor to the agglomeration of NS sols and only small concentrations of calcium ions can drastically affect the dispersion quality.

摘要

纳米二氧化硅（NS）的分散质量是影响和控制纳米二氧化硅增强混凝土材料特性的一个重要参数。在本研究中，使用动态光散射研究了胶体纳米二氧化硅在模拟混凝土环境中的分散质量。通过创建一种模拟超高性能混凝土流体状态下离子浓度和pH值的合成孔隙溶液来模拟混凝土环境。使用了四种胶体纳米二氧化硅样品，粒径范围为5至75纳米，具有不同的固体含量和稳定离子。研究发现，钠稳定的20纳米NS溶胶在含有钾离子的各种pH值下，在2 wt%的固体浓度下仍保持分散状态。钙离子是NS溶胶团聚的主要因素，仅少量的钙离子就能显著影响分散质量。