Effect of polycarboxylic acid modified graphene oxide on properties of cement-based materials
Polycarboxylic acid modified graphene oxide composite(GO-PCE)was prepared by surface activation of graphene oxide(GO)and grafting copolyacrylic acid and isoprenol polyoxyethylene ether.The molecular structure of GO-PCE was determined by infrared spectrum and thermogravimetric analysis,and the properties of GO-PCE doped cement paste and mortar were tested.The results show that proper amount of GO-PCE can obviously improve the workability of cement paste.When the content is 0.03%,the fluidity of cement paste increases by 102.86%compared with that of GO.When the GO-PCE content is 0.03%and 0.05%,the 28 d compressive strength of mortar is increased by 17.95%and 19.44%,respectively.The dispersion of GO-PCE was better than that of GO in the cement paste,resulting in the enhancement performance of GO lamellae could be effectively exerted,the hydration process was accelerated to promote the growth of nucleation of hydration products,and the size of the calcium hy-droxide crystals was further refined to make the structure of the cement matrix denser.