Multifunctional hexagonal boron nitride dispersions based in xanthan gum for use in drilling fluids

The development of efficient drilling fluids through nanotechnology has the goal to improve the extraction processes in the oil industry. This work aims to study the thermal and the rheological behavior of oxidized hexagonal boron nitride (h-BN-Oxi) bidimensional (2D) nanostructures dispersed directly in xanthan gum. Morphological and structural characterization of the h-BN-Oxi nanostructures have shown the successful oxidation of the h-BN, which have enhanced the exfoliation and dispersion of the 2D nanomaterials with high surface area in the polymer matrix. Therefore, different concentrations, ranging from 0 to 60 mg mL−1 of h-BN-Oxi were obtained by the liquid exfoliation method. The thermal conductivity of the h-BN-Oxi suspensions was evaluated and have shown an increase for all concentrations. The rheological properties were investigated, and the results revealed that the increase of h-BN-Oxi concentration led to the increase of viscosity with the concentration of h-BN-Oxi nanomaterials. Moreover, it was observed a transition from pseudoplastic behavior for concentration up to 15 mg mL−1, to a yield stress nanofluid above, well described by the Herschel-Bulkley model. This behavior was ascribed to the complex network obtained by the h-BN-Oxi nanostructures with the xanthan gum. Thus, exploitation of h-BN-Oxi dispersions based in xanthan gum as an additive for drilling fluid can have advantageous due to its multifunctional properties like enhanced thermal conductivity and enhanced viscosity for use in deeper offshore.