硅灰/氧化石墨烯在水泥硬化浆体中的分散性研究  

Study on dispersion of silica fume/graphene oxide in hardened cement paste

作　　者：杜长青 王章轩 仝腾[2] 刘骁繁 刘亮 DU Changqing;WANG Zhangxuan;TONG Teng;LIU Xiaofan;LIU Liang(Construction Branch of State Grid Jiangsu Electric Power Co.,Ltd.,Nanjing 210011,China;School of Civil Engineering,Southeast University,Nanjing 210096,China)

机构地区：[1]国网江苏省电力有限公司建设分公司,江苏南京210011 [2]东南大学土木工程学院,江苏南京210096

出　　处：《无机盐工业》2023年第11期115-120,共6页Inorganic Chemicals Industry

基　　金：国网江苏省电力有限公司科技项目(J2022080)。

摘　　要：氧化石墨烯用作水泥增强材料的研究已取得一定进展,而硅灰通常用作水泥掺合料。已有研究报道了利用硅灰/氧化石墨烯复合材料制备水泥基材料,但硅灰辅助分散氧化石墨烯的理论研究尚不完善。基于此,采用超声法制备不同掺量的硅灰/氧化石墨烯混合悬浮液,分析了该悬浮液在水泥孔隙液中的分散性,并制备了硅灰/氧化石墨烯水泥硬化浆体。结果表明:硅灰在水泥孔隙溶液中剥离了氧化石墨烯片层,改善了氧化石墨烯的分散稳定性;当m(氧化石墨烯)/m(水泥)为0.25%、m(硅灰)/m(水泥)为10%时,水泥水化28 d抗折、抗压强度分别可达12.3 MPa和73.2 MPa,相较于不掺硅灰的样品分别提高了48.19%和18.06%。硅灰在水泥复合材料中发挥了双重作用,一方面与Ca(OH)_(2)反应,避免了水化解离出来的Ca^(2+)争夺氧化石墨烯;另一方面作为填料填充C-S-H凝胶空隙,提高了水泥内部致密性。The research of graphene oxide(GO)as cement reinforcing material has made some progress,and silica fume(SF)is commonly used as cement admixture.It has been reported that SF/GO is compounded to prepare cement-based mate-rials,but the theoretical study of SF-assisted dispersion of GO remains incomplete.Consequently,different dosage of SF/GO suspension was prepared by ultrasonic method,the dispersibility of the suspension in cement pore solution was analyzed.SF/GO hardened cement paste was also prepared.The results of microscopic analysis indicated that SF stripped the GO sheets in cement pore solution,the dispersion and stability of GO were improved.When m(GO)/m(cement)was 0.25% and m(SF)/m(cement)was 10%,the 28 d flexural and compressive strength of the composites were 12.3 MPa and 73.2 MPa,re-spectively,which were increased by 48.19% and 18.06% compared to the sample without SF.SF served a dual purpose in the cement composites by reacting with Ca(OH)_(2) to avoid competition for GO from Ca^(2+)dissociated by hydration,and by fill-ing gaps in the C-S-H structure to improve the composites'internal density.

关 键 词：氧化石墨烯 硅灰 水泥 分散性 水泥孔隙溶液 

分 类 号：TQ177.6[化学工程—硅酸盐工业]