In-situ high-strength Poly(styrene-methyl methacrylate)-2D nanofiller composite microbeads as potential proppants in hydraulic fracturing

Many fracturing treatments involve the injection of solid proppants to ensure that hydraulic fractures remain open after they are created. Traditional proppants have drawbacks, including reduced propped-fracture volume and causing abrasion to pumping equipment. To solve these problems, this study presents copolymer composite microbeads that incorporate 2D nanofillers as high-strength in situ proppants for hydraulic fracturing operations. The poly(styrene-methyl methacrylate)-2D nanofiller (PS-PMMA-2D nanofiller) composite microbeads were synthesized using the emulsion polymerization technique. Various 2D nanofillers, including commercial graphene (CG), hexagonal boron nitride nanosheets (h-BN), and a combination of CG and h-BN (CG:BN), were utilized in the preparation of the copolymer composite microbeads. The morphology of the composite microbeads was thoroughly characterized using scanning electron microscopy (SEM), while Fourier Transform Infrared (FT-IR) spectroscopy and X-ray diffraction (XRD) methods indicated the successful formation of the composites. Differential scanning calorimetry (DSC) was employed to assess thermal stability, revealing that the composite's glass transition temperature (T_g) is 104.4 °C. Notably, these copolymer composite microbeads demonstrated impressive crush resistance, achieving levels of up to 12,000 psi. As such, they hold significant potential as candidates for successful hydraulic fracturing applications.