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A novel oilwell cement slurry was prepared with in situ polymerized epoxidized A/F bisphenol–chitosan and characterized by 29Si NMR and EPR spectroscopy. The hydrated and cured cement slurry evidenced the presence of unreacted clinker phases identified by the presence of orthosilicate groups along with the presence of hydration products identified by short linear polymeric silicate units typical of calcium silicate hydrate (CSH). Two main Fe3+ domains and Mn2+‐related hyperfine sextets were detected by EPR spectroscopy. After long‐term contact with an API acidizing fluid, the features of the 29Si NMR and EPR spectra did not change appreciably. The kinetics of overall solids dissolution upon contact with the hot acidizing fluid was modeled with the Avrami‐Erofe'ev equation. The kinetic parameters are not very sensitive to changes of temperature. The values of the Avrami exponent suggest that diffusion‐controlled processes without chemical reactions govern the overall rate of interaction processes or are partially involved in it. The results indicate that the A/F bisphenol–chitosan polymeric network can improve significantly the chemical stability of cement slurries in the presence of acidizing fluids and may be a good option for oil and gas industry. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41044.

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Inadequate zonal isolation in oil wells can provoke safety and environmental problems. New cement slurries can avoid such problems. In this work, novel cement slurries were prepared in the presence of seawater with in situ-formed epoxy resin–ethylenediamine. The new slurries were tested in relation to their mechanical properties and characterized by FTIR, XRD, TG/DTG, porosimetry by N2 adsorption-desorption and solid-state 29Si and 27Al NMR. Some kinetic features of long-term contact of the slurries with in situ-generated mud-acid were performed to evaluate the performances of the new slurries in routine acidizing procedures in oil well industry. The experimental kinetic data were well fitted to order-variable exponential kinetic model and a factorial design of four variables (24). In these studies, it was possible to evaluate in detail how some important experimental factors act on the quantities of acid that interact with the pastes, as well as to verify how these factors affect the speed with which the mud-acid interacts with the slurries. The results strongly suggest that the interactions occurred at epoxy/ethylenediamine cement slurry/mud-acid interfaces are due to surface reactions with preservation of the chemical structures of the cement slurries, even after long-term contact with mud-acid. The new cement slurry present good features to be used in environmental-friendly procedures in oil well field.