氧化石墨烯分散液对水泥净浆水化和力学性能影响机理分析

Effect mechanism analysis of graphene oxide dispersion on hydration and mechanical properties of cement paste

为研究氧化石墨烯(GO)掺量对水泥净浆水化和力学性能的影响,采用改进Hummers法和超声波分散法制备GO片层分散液,利用傅里叶红外光谱(FTIR)和X-射线衍射(XRD)表征GO;研究了GO掺量对水泥净浆抗压、抗折强度的影响规律,并从微观角度揭示了GO分散液对水泥净浆的调控机理。结果表明:与普通水泥净浆相比,掺入适量的GO能够促进水泥水化进程,提高水泥净浆中的化学水结合量,水化晶体互相缠绕、交织形成规整有序的多面体状微结构,使水泥净浆的早期力学性能显著提高,最佳GO掺量为水泥质量的0.03%。适量的GO能够提高水泥净浆的抗压和抗折强度,促进水泥净浆水化晶体的生长,改变晶体的尺寸和形状,实现对水泥净浆微结构的调控。

In order to study the influence of GO content on hydration and mechanical properties of cement paste,graphene oxide dispersion was prepared by improving Hummers method and ultrasonic dispersion method.The resulting GO dispersion were characterized by FTIR and X-ray photoelectron spectroscopy.The influence of GO additives on the compressive strength and flexural strength was investigated.The mechanism of GO dispersion regulation on cement paste was revealed by the microscopic perspective.The results indicated that compared with the normal cement paste,the appropriate amount of graphene oxide can promote the cement hydration process and improve the chemical water binding amount in the cement paste.The early mechanical properties of the cement paste were improved obviously because the cement hydration crystals of cement-based composite formed a neat and orderly polyhedral crystals.The best dosage of GO was 0.03%of the cement quality.The appropriate amount of GO dispersion could improved the compressive and flexural strength of cement paste,promote the growth of cement hydration crystals,change the size and shape of the crystal,and effectively control the microstructure of cement paste.