氧化石墨烯增强增韧水泥基复合材料的研究

Study on reinforcing and toughening of graphene oxide to cement-based composites

用Hummers法对石墨进行氧化后再用超声波进行分散制备纳米氧化石墨烯(GO)分散液。研究GO对掺有聚羧酸系减水剂(PCs)的水泥净浆流动度、粘度、凝结时间、石泥石孔结构和水泥砂石的耐折强度、抗压强度的影响。研究结果表明,纳米氧化石墨烯掺量为15mg/(100g水泥)时,使净浆流动度和凝结时间稍有降低,所得石泥石的中大孔隙率减少,结构致密,硬化水泥砂浆的耐折强度和抗压强度显著提高。硬化水泥石的XRD和SEM测试结果表明,纳米氧化石墨烯片层对水泥水化晶体产物的形成有模板效应,能够促使水泥石形成微小、形状统一的晶体结构,研究纳米氧化石墨烯增强增韧混凝土对于构建高性能、长寿命混凝土具有重要的意义。

Nano-graphene oxide（GO） aqueous was prepared by oxidizing graphite according to Hummers method and ultrasonic dispersion.The effects of GO on the concrete properties doped with polycarbonate superplasticizer（PCs） were investigated by measuring the fluidity,viscosity and setting time of cement pastes,pore structure of hardened cement paste,folding strength and compression strength of mortar in the presence of PCs.The results indicated that nano-graphene oxide could make lightly decrease of fluidity and setting time,could make hardened cement paste become dense,could decrease larg pore number and could remarkably increase folding and compression strength of mortar.The results of XRD and SEM testing showed that the GO could lead and promote cement hydration to produce more crystal products with regular shape,which hinted the template role of GO for cement hydration.Therefore,research on the effect of nano-graphene oxide on cement composite microstructure is important to reinforcement and toughening of concrete and prolongs concrete life.