摘要
将乙二胺与氧化石墨烯(GO)通过脱水缩合反应制备了表面功能化的GO-NH_(2),表面功能化改善了GO的亲水性,减弱了GO片层间的相互作用。随后将GO-NH_(2)掺入地聚物混凝土中,研究了表面功能化和GO-NH_(2)掺杂量对地聚物混凝土力学性能、微观形貌、孔径分布和抗盐蚀性能的影响。结果表明,表面功能化后的GO-NH_(2)水接触角从90.1°降低至64.9°,降低了GO片层之间发生团聚的概率。GO表面功能化和增大GO-NH_(2)的掺杂量均能够提升地聚物混凝土的水化程度,增大小尺寸孔隙的占比。随着GO-NH_(2)掺杂量的增多,地聚物混凝土的抗压强度和抗折强度均表现出先增大后降低的趋势。0.09%GO-NH_(2)在28 d时的抗压强度和抗折强度均达到了最大值,分别为47.7和7.2 MPa;其最大载荷和最大应力分别达到了214.3 N和3.9 mm。在Na_(2)SO_(4)溶液中进行干湿循环,地聚物混凝土中的腐蚀产物主要是钙矾石AFt和石膏,干湿循环50次时,0.09%GO-NH_(2)的质量损失率最低仅2.61%,相对动弹性模量最大为77.22%,具有最优的力学性能和抗盐蚀性能。
Surface functionalized GO-NH_(2)was prepared by dehydration condensation reaction of ethylenediamine and graphene oxide(GO).Surface functionalization improved the hydrophilicity of GO and weakened the interlayer interactions of GO.Subsequently,GO-NH_(2)was incorporated into geopolymer concrete,and the effects of surface functionalization and GO-NH_(2)doping on the mechanical properties,microstructure,pore size distribution,and salt corrosion resistance of geopolymer concrete were studied.The results showed that the surface functionalized GO-NH_(2)water contact angle decreased from 90.1°to 64.9°,reducing the probability of aggregation between GO layers.Both surface functionalization of GO and increasing the doping amount of GO-NH_(2)could enhance the hydration degree of geopolymer concrete and increase the proportion of large-sized pores.With the increase of GO-NH_(2)doping,the compressive strength and flexural strength of geopolymer concrete showed a trend of first increasing and then decreasing.The compressive strength and flexural strength of 0.09%GO-NH_(2)reached their maximum values at 28 d,which were 47.7 and 7.2 MPa,respectively.Its maximum load and maximum stress reached 214.3 N and 3.9 mm,respectively.The corrosion products in geopolymer concrete during wet-dry cycles in Na_(2)SO_(4)solution were mainly ettringite AFt and gypsum.After 50 wet-dry cycles,the mass loss rate of 0.09%GO-NH_(2)was the lowest at only 2.61%,and the maximum relative dynamic elastic modulus was 77.22%.It had the best mechanical properties and salt corrosion resistance.
作者
吕大为
崔岳
LYU Dawei;CUI Yue(School of Civil and Transportation Engineering,Henan University of Urban Construction,Pingdingshan 467036,China;Henan Shenghongxing Engineering Consulting Management Co.,Ltd.,Pingdingshan 467036,China)
出处
《功能材料》
北大核心
2025年第7期7093-7102,共10页
Journal of Functional Materials
基金
国家自然科学联合基金项目(U1504508)。
关键词
表面功能化
氧化石墨烯
地聚物混凝土
力学性能
抗盐蚀性能
surface functionalization
graphene oxide
geopolymer concrete
mechanical properties
salt corrosion resistance performance
