US Patent 11702587 Coated proppants and methods of making and use thereof

Coated proppants include a proppant particle, a surface copolymer layer surrounding the proppant particle, and a resin layer surrounding the surface copolymer layer. The surface copolymer layer includes a copolymer of at least two monomers chosen from styrene, methyl methacrylate, ethylene, propylene, butylene, imides, urethanes, sulfones, carbonates, and acrylamides, where the copolymer is crosslinked by divinyl benzene. The resin layer includes a cured resin. Methods of preparing the coated proppants include preparing a first mixture including at least one polymerizable material, an initiator, and a crosslinker including divinyl benzene; contacting the first mixture to a proppant particle to form a polymerization mixture; heating the polymerization mixture to cure the polymerizable material and form a polymer-coated particulate; preparing a second mixture including the polymer-coated substrate, an uncured resin, and a solvent; and adding a curing agent to the second mixture to cure the uncured resin and form the coated proppant.