Zhou Yong, Wang Yuliang, Gao Tianming, Ling Yifeng, Jiang Nengdong, Tawfek Abdullah M, Yuan Huaqiang
Shandong Hi-Speed Group Co., Ltd., Jinan 250002, China.
School of Qilu Transportation, Shandong University, Jinan 250002, China.
Materials (Basel). 2022 Oct 19;15(20):7308. doi: 10.3390/ma15207308.
As promising next-generation conducting materials, Graphene Nanoplatelets (GNPs) have been widely used to enhance the mechanical and pressure-sensitive properties of cement-based materials. However, this beneficial effect highly depended on its dispersion. In this study, polyvinyl pyrrolidone (PVP) surfactant, high-speed shear, and ultrasonication were used to disperse GNPs. To fully exert the mechanical and pressure-sensitive properties and enhance the dispersion effect of GNPs in cement-based materials, the dispersing method parameters, including PVP concentration, ultrasonication time, shear time, and rate, were optimized. The dispersion degree of GNPs was evaluated by absorbance. The results show that the optimal dispersion parameters were 10 mg/mL of PVP concentration, 15 min of ultrasonication time, 15 min of shear time, and 8000 revolutions per minute (rpm) of shear rate. In addition, the effect of GNPs dosage (0.05, 0.1, 0.3, 0.5, 0.7, and 1.0 wt%) on the setting time, flowability, and mechanical and pressure-sensitive properties of cement mortar were examined. Results reveal that the optimum dosage of GNPs was found at 1.0 wt%.
作为很有前景的下一代导电材料，石墨烯纳米片（GNPs）已被广泛用于增强水泥基材料的力学性能和压敏性能。然而，这种有益效果高度依赖于其分散性。在本研究中，使用聚乙烯吡咯烷酮（PVP）表面活性剂、高速剪切和超声处理来分散GNPs。为了充分发挥GNPs在水泥基材料中的力学性能和压敏性能并增强其分散效果，对包括PVP浓度、超声处理时间、剪切时间和速率在内的分散方法参数进行了优化。通过吸光度评估GNPs的分散程度。结果表明，最佳分散参数为PVP浓度10 mg/mL、超声处理时间15分钟、剪切时间15分钟和剪切速率8000转/分钟（rpm）。此外，研究了GNPs用量（0.05、0.1、0.3、0.5、0.7和1.0 wt%）对水泥砂浆凝结时间、流动性以及力学性能和压敏性能的影响。结果表明，GNPs的最佳用量为1.0 wt%。
