Hydrophobic polymer-modified nanosilica as effective shale inhibitor for water-based drilling mud

Novel Use of a Superhydrophobic Nanosilica Performing Wettability Alteration and Plugging in Water-Based Drilling Fluids for Wellbore Strengthening

“…33,34 The nanomaterials can be divided into three categories: the organic nanomaterials, 35,36 the inorganic nanomaterials, 28 and the hybrid of inorganic nanomaterials and polymers. 10,37 The organic nanoparticles usually have a high elastic modulus, which could change their shape according to the size of the throat and form dense plugging. However, the organic nanoparticles cannot withstand high temperatures, which has limited their use as plugging agents.…”

“…Shale hydration is essentially the hydration of the layered clay minerals, including surface hydration and osmotic hydration. , In surface hydration, driven by the surface energy from the shale, water molecules would absorb on the surface of the layered clay mineral crystals. , In the beginning, only water monolayer molecules are absorbed on the crystal surface. Then, the second and subsequent layers absorb the previous water layer by hydrogen bonds.…”

“…Apart from shale hydration, the inefficiency of the plugging property for the nanoscale pores and microfractures inside the shale further exacerbates wellbore instability. , The nanoscale pores and fractures were highly developed inside the shale, providing large numbers of avenues for water to enter it, enhancing the contact of water and clay minerals and causing the exacerbation of shale mechanical stability. , With the fast development of nanotechnology, , nanomaterials have been proposed to plug the nanoscale pores and fractures in shale. , The nanomaterials can be divided into three categories: the organic nanomaterials, , the inorganic nanomaterials, and the hybrid of inorganic nanomaterials and polymers. , The organic nanoparticles usually have a high elastic modulus, which could change their shape according to the size of the throat and form dense plugging. However, the organic nanoparticles cannot withstand high temperatures, which has limited their use as plugging agents.…”

In Situ Shale Wettability Regulation Using Sophisticated Nanoemulsion to Maintain Wellbore Stability in Deep Well Drilling

“…32−36 And various chemicals, such as silanes, fatty acids, and their salts, as well as fluoropolymers, are used for hydrophobic modification and to reduce surface-free energy. 37,38 Among these, there is no question that silane coupling agents play a vital role in enabling effective combinations of inorganic fillers and organic elastomers to improve adhesion to inorganic materials. In addition, organosilanes have been widely applied in the aerospace, automotive, construction, and textile industries owing to chemical stability, forming durable bonds with metal, glass, concrete, and other surfaces that are resistant to heat, UV, alkali, moisture, and water, as well as environmentally friendly.…”

“…Inspired by the hydrophobic phenomena observed from lotus leaves and water striders, the artificial hydrophobic surfaces have been applied to many fields, , such as antifouling, oil and water separation, anticorrosion, and ice suppression . To minimize the interaction between shale and water, wettability regulation, altering shale surface from hydrophilic to hydrophobic, was hitherto recognized as a promising solution to address wellbore instability issues. , Moreover, recent studies have mainly focused on applying hydrophobic associated polymers and hydrophobic nanoparticles, such as nano SiO 2 to drilling fluids, to form a hydrophobic filter cake via electron interaction and adsorption, preventing water invasion into shale formation. − And various chemicals, such as silanes, fatty acids, and their salts, as well as fluoropolymers, are used for hydrophobic modification and to reduce surface-free energy. , Among these, there is no question that silane coupling agents play a vital role in enabling effective combinations of inorganic fillers and organic elastomers to improve adhesion to inorganic materials. In addition, organosilanes have been widely applied in the aerospace, automotive, construction, and textile industries owing to chemical stability, forming durable bonds with metal, glass, concrete, and other surfaces that are resistant to heat, UV, alkali, moisture, and water, as well as environmentally friendly.…”