添加剂对酸性硅溶胶及料浆胶凝与流变行为的影响  

Effects of Additives on Gelation Process and Rheological Behavior of Acid Silica Sol and Slurry

作　　者：杨雨菲 刘浩[1] 王周福[1] 刘文元 马妍[1] 王玺堂[1] 柳茂林[1] YANG Yufei;LIU Hao;WANG Zhoufu;LIU Wenyuan;MA Yan;WANG Xitang;LIU Maolin(The State Key Laboratory of Refractories and Metallurgy,Wuhan University of Science and Technology,Wuhan 430081,China)

机构地区：[1]武汉科技大学,省部共建耐火材料与冶金国家重点实验室,武汉430081

出　　处：《硅酸盐通报》2021年第10期3292-3297,共6页Bulletin of the Chinese Ceramic Society

基　　金：国家自然科学基金(U20A20239,51672195);国家级大学生创新创业训练计划(202110488002)。

摘　　要：以酸性硅溶胶及其结合料浆为研究对象,通过对比胶凝时间、黏度、触变环面积、剪切应力等流变参数,研究了聚丙烯酰胺、氢氧化镁、柠檬酸三铵等对酸性硅溶胶及结合料浆流变行为、凝聚过程的作用规律。结果表明:氢氧化镁电离出Mg2+促进了酸性硅溶胶的缩合反应,对酸性硅溶胶胶凝过程的影响较为显著;氢氧化镁添加量的增加,增大了胶凝速度,酸性硅溶胶的稳定性下降。聚丙烯酰胺作为阴离子表面活性剂,通过空间位阻效应,缔合溶胶中的氢键,在溶胶中形成三维网络结构,同时聚丙烯酰胺水解吸附在溶胶胶团颗粒表面,加快了SiO2粒子的絮凝,提高了酸性硅溶胶及其结合料浆的黏度。控制柠檬酸三铵的含量低于10 mg/mL,有助于降低硅溶胶结合料浆的黏度,提高体系的稳定性。Taking acid silica sol and its bonded slurry as the research object, the effects of additives(polyacrylamide, magnesium hydroxide, and triammonium citrate) on the rheological behavior and gelation process of acid silica sol and its bonded slurry were researched by comparing rheological parameters, such as gelation time, viscosity, thixotropic area, and shear stress. The results show that Mg2+ ionized by magnesium hydroxide promotes the condensation reaction of acid silica sol, and presents significant effects on the gelation process of acid silica sol. And the increase of magnesium hydroxide addition increases the gelation speed and decreases the stability of acid silica sol. As an anionic surfactant, polyacrylamide associates the hydrogen bonds to form a three-dimensional network structure in the sol through steric hindrance. At the same time, polyacrylamide is hydrolyzed and adsorbed on the surface of the sol micelle particles, which accelerates the flocculation of SiO2 particles, and increases the viscosity of acid silica sol and its bonded slurry. Addition of triammonium citrate below 10 mg/mL is conductive to the lowered viscosity and enhanced stability of silica sol bonded slurry.

关 键 词：不定形耐火材料 酸性硅溶胶 料浆 结合剂 添加剂 黏度 触变性 稳定性 

分 类 号：TQ175[化学工程—硅酸盐工业]