Synthesis, characterization and hydration analysis of a novel epoxy/superplasticizer oilwell cement slurry--some mechanistic features by solution microcalorimetry.

A new epoxy/polyacrylate-modified oilwell cement slurry was synthesized. The features of the new slurry were evaluated in relation to a standard cement slurry (w/c=0.5). The characterization of the slurries was performed by Raman, XRD, TG/DTG and solid-state diffuse reflectance spectroscopy. The main morphological features of the new slurry were preserved, even after long-term contact with HCl in aqueous solution. The hydration of the slurries was studied by heat-conduction microcalorimetry. The exothermic microcalorimetric outputs were well fitted to a three-parameter kinetic model. The analysis of both thermodynamic and kinetic results from microcalorimetry have pointed out that diffusional growth from non-stoichiometric mixtures is the main mechanistic feature of the hydration of the cement slurries. The results of this study underline the excellent features of the new epoxy/superplasticizer-modified cement slurry for using in severe acidic environments of oilwells.