Oil-swellable, surface-treated elastomeric polymer and methods of using the same for controlling losses of non-aqueous wellbore treatment fluids to the subterranean formation

A method of forming a lost circulation material (LCM), comprising:

• applying a crosslinker to the surface of a plurality of elastomeric polymer particles to form a first mixture, the plurality of elastomeric polymer particles comprising an olefinically unsaturated hydrocarbon monomer and a monomer comprising an epoxy pendant group, the molar ratio of unsaturated hydrocarbon monomer to epoxy containing monomer is in the range of about 75:25 to about 99:1, and the crosslinker comprising an amine, wherein the crosslinker crosslinks the epoxy groups of the plurality of elastomeric polymer particles, wherein applying the crosslinker to the surface of the plurality of elastomeric polymer particles to form the first mixture comprises spray coating the crosslinker on the plurality of elastomeric polymer particles;
• adding an anti-agglomerating agent to the first mixture to form a second mixture, wherein the anti-agglomerating agent comprises at least 0.5% by weight of the plurality of elastomeric polymer particles;
• and
• agitating the second mixture at a temperature of at least 200° F. for a duration to produce the lost circulation material (LCM), wherein the plurality of elastomeric polymer particles in the LCM are crosslinked in a solid state by the crosslinker.