摘要
氧化石墨烯能显著增强增韧水泥基复合材料,但会对水泥浆体的流动性能带来负面影响。通过硅烷偶联剂乙烯基三甲氧基硅烷对氧化石墨烯(GO)进行改性,制备出带有乙烯基的硅烷改性氧化石墨烯(S-GO),将S-GO与羧酸单体进行共聚合反应,得到硅烷改性氧化石墨烯-聚羧酸复合物(P-S-GO)。利用FTIR与XRD等手段对GO、S-GO与P-S-GO的微观结构、元素组成及分散性进行表征;同时,将P-S-GO掺入水泥净浆中,测试其流动度与流变性能。结果表明:硅烷偶联剂能通过缩合反应成功接枝到氧化石墨烯上,形成富含活性双键的氧化石墨烯,并通过与羧酸单体和大单体的共聚合反应,合成P-SGO复合物。与GO相比,P-S-GO在水泥浆体系中有着更良好的分散能力;将P-S-GO掺入水泥浆中可以有效改善GO对于水泥浆体工作性的负面影响,改善流动度与流变性能。
The addition of graphene oxide(GO)to cement paste significantly increases its toughness,however its fluidity is adversely affected.GO was first reacted with vinyltrimethoxysilane to produce a silane-modified graphene oxide(S-GO),which was then copolymerized with acrylic acid and a water reducing agent,isobutaenol polyoxyethylene ether(molecular mass 2400),to obtain a silane and copolymer-modified GO(P-S-GO)which acted as a water-reducing agent of the cement paste.A copolymer without GO was prepared under the same conditions for comparison.The structure,elemental composition and dispersibility of GO,S-GO and P-S-GO in a simulated cement environment(saturated lime water)were investigated by FTIR,XRD and a sedimentation test.The fluidity and rheology of the cement pastes with added GO,copolymer or P-S-GO were investigated.Results showed that vinyltrimethoxysilane reacted with the-OH group on the GO sheets to form an ether bond and the copolymer was grafted onto a vinyl group of S-GO by an addition reaction to produce the P-S-GO.The P-S-GO has a better dispersibility in saturated lime water with a negligible amount of aggregation compared to GO and a significant agglomeration occurs for GO.The addition of the P-S-GO to the cement pastes improves the fluidity and rheological properties compared with GO,offsetting the negative impact of GO and increasing the toughness of the resulting cements.
作者
王琴
李时雨
潘硕
郭紫薇
WANG Qin;LI Shi-yu;PAN Shuo;GUO Zi-wei(Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation, University of Civil Engineering and Architecture,Beijing 100044,China)
出处
《新型炭材料》
SCIE
EI
CAS
CSCD
北大核心
2018年第2期131-139,共9页
New Carbon Materials
基金
国家自然科学基金(00881915021)
北京市自然科学基金(8182014).
关键词
氧化石墨烯
硅烷偶联剂改性
流动度
流变性能
Graphene oxide
Silane coupling agent modified
Fluidity
Rheological property
作者简介
通讯作者:王琴,副教授.E-mail:wangqin@bucea.edu.cn
