Thermally-activated, high temperature particulate suspending agents and methods relating thereto

A treatment fluid comprising:

• an aqueous fluid,
• a plurality of particulates, and
• a particulate suspending agent comprising a crosslinked polymer particulate, wherein the crosslinked polymer particulate is produced from a reaction comprising:
• a first monofunctional monomer, and
• an orthoester crosslinker that comprises an orthoester linkage and at least two crosslinking moieties.

A method comprising:

• providing a treatment fluid comprising an aqueous liquid, a plurality of particulates, and a particulate suspending agent, wherein the particulate suspending agent comprises a crosslinked polymer particulate that comprises a polymer crosslinked with an orthoester crosslinker that comprises an orthoester linkage and at least two crosslinking moieties;
• placing the treatment fluid in a wellbore penetrating a subterranean formation with a bottom hole static temperature of about 150° F. or greater;
• and
• allowing the orthoester linkage to degrade thereby allowing at least some of the polymer to dissolve and suspend the particulates.

A method of producing a particulate suspending agent, the method comprising:

• providing an oil solution comprising an oil-based solvent and a surfactant;
• providing a monomer mixture comprising an aqueous liquid and a first monofunctional monomer;
• forming an inverse suspension with the monomer mixture and the oil solution;
• reacting the monomer mixture in the inverse suspension with a free-radical initiator to form a polymer particulate;
• isolating the polymer particulate;
• and
• diffusing an orthoester crosslinker into the polymer particulate so as to form a crosslinked polymer particulate.