%0 Journal Article
%T Uniformly Dispersed and Re-Agglomerated Graphene Oxide-Based Cement Pastes: A Comparison of Rheological Properties, Mechanical Properties and Microstructure
%A Chang-Le Fang
%A Feng Xing
%A Hao-Dao Li
%A Wu-Jian Long
%J Archive of "Nanomaterials".
%D 2018
%R 10.3390/nano8010031
%X The properties of graphene oxide (GO)-based cement paste can be significantly affected by the state of GO dispersion. In this study, the effects of uniformly dispersed and re-agglomerated GO on the rheological, mechanical properties and microstructure of cement paste were systematically investigated. Two distinct dispersion states can be achieved by altering the mixing sequence: Polycarboxylate-ether (PCE) mixed with GO-cement or cement mixed with GO-PCE. The experimental results showed that the yield stress and plastic viscosity increased with the uniformly dispersed GO when compared to those of re-agglomerated GO cement paste. Moreover, the 3-day compressive and flexural strengths of uniformly dispersed GO paste were 8% and 27%, respectively, higher than those of re-agglomerated GO pastes. The results of X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy analyses demonstrated that uniformly dispersed GO more effectively promotes the formation of hydration products in hardened cement paste. Furthermore, a porosity analysis using mercury intrusion porosimetry revealed that the homogeneous dispersion of GO can better inhibit the formation of large-size pores and optimize the pore size distribution at 3 and 7 days than the re-agglomerated GO
%K graphene oxide (GO)
%K uniform dispersion
%K re-agglomeration
%K rheological properties
%K hydration products
%K cement paste
%U https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5791118/