Zeng Min, Xing Yubing, Xie Yongxu, Xu Dawei, Miao Xia, Guo Jintang
Sinopec Research Institute of Petroleum Engineering Co., Ltd., Beijing 102206, China.
School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China.
Materials (Basel). 2024 May 23;17(11):2523. doi: 10.3390/ma17112523.
The aggregation of graphene oxide (GO) during the hydration process limits its wide application. Polymer superplasticizers have been used to improve the dispersion state of GO due to their adsorption and site-blocking effects, though the formation of a large amount of foam during the mixing process weakens the mechanical properties of cement. A highly dispersed amphoteric polycarboxylate superplasticizer-stabilized graphene oxide (APC/GO) toughening agent was prepared by electrostatic self-assembly. Results demonstrate that the APC/GO composite dispersed well in a cement pore solution due to the steric effect offered by the APC. Additionally, the well-dispersed GO acted as an antifoaming agent in the cement since GO nanosheets can be absorbed at the air-liquid interface of APC foam via electrostatic interactions and eliminate the air-entraining effect. The well-dispersed APC/GO sheets promoted cement hydration and further refined its pore structure owing to the nucleation effect. The flexural and compressive strength of the cement containing the APC/GO composite were enhanced by 21.51% and 18.58%, respectively, after a 7-day hydration process compared with a blank sample. The improved hydration degree, highly polymerized C-S-H gel, and refined pore structure provided enhanced mechanical properties.
氧化石墨烯（GO）在水化过程中的团聚限制了其广泛应用。聚合物高效减水剂因其吸附和位阻效应已被用于改善GO的分散状态，尽管在搅拌过程中形成大量泡沫会削弱水泥的力学性能。通过静电自组装制备了一种高度分散的两性聚羧酸系高效减水剂稳定的氧化石墨烯（APC/GO）增韧剂。结果表明，由于APC提供的空间位阻效应，APC/GO复合材料在水泥孔隙溶液中分散良好。此外，分散良好的GO在水泥中起到消泡剂的作用，因为GO纳米片可通过静电相互作用吸附在APC泡沫的气液界面上，消除引气效应。由于成核效应，分散良好的APC/GO片层促进了水泥水化并进一步细化了其孔结构。与空白样品相比，经过7天水化过程后，含有APC/GO复合材料的水泥的抗折强度和抗压强度分别提高了21.51%和18.58%。水化程度的提高、高度聚合的C-S-H凝胶以及细化的孔结构提供了增强的力学性能。
