钙基地聚合物微观孔隙结构特征研究

Characteristics of Microscopic Pore Structure of Calcium-Based Geopolymer

采用氮气吸附法对钙基地聚合物孔隙进行测定,通过吸附等温线和孔径分布分析表征了其孔隙结构特征并讨论了影响孔隙结构的因素.结果表明:钙基地聚合物孔隙结构较复杂,主要由无害孔和少害孔组成,同时存在少量的有害孔,孔隙以两端开放的圆筒状孔、两壁平行的狭缝状孔及细颈广体的墨水瓶形孔等开放性孔为主;孔隙主孔介于3~50nm,占总孔隙体积的84.87%,占总比表面积的91.91%,孔径小于50nm的无害孔和少害孔提供了主要的孔比表面积和孔隙体积;碱性激发剂掺量和偏高岭土掺量均是影响钙基地聚合物孔隙结构的重要因素.

Nitrogen adsorption method was adopted to measure the pore of calcium-based geopolymer, and pore structure of calcium-based geopolymer characterized and the factors influencing the pore structure were discussed by analyzing the adsorption isotherm and the distribution of aperture. The results show that the pore structure of calcium-based geopolymer is complicated, mainly composed of harmless pores and less harmful pores, as well as a few harmful pores. The pores mainly include cylindrical pores with open ends, slit-shaped pores with parallel walls and ink bottle-shaped pores with narrow neck and broad body. The diameter range of the main holes in pore is 3 -50 nm, which constitute 84.87 % of the total pore volume, and 91.915 of the pore specific surface area. The harmless and less harmful pores whose aperture is less than 50 nm provide most part of the pore specific surface area and the total pore volume. The alkali activator and proportion of metaka- olin are important factors that affect the pore structure of calcium-based geopolymer.