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US 10,851,291 B2Granted
Coated particles, methods for their manufacture and for their use as proppants
AssigneeCovestro LLC
InventorsStephen J. Harasin, Kenneth R. Riddle, Michael T. Wellman
Life of this patent
Estimating the term…
Abstract
Disclosed are coated particles. The coated particles include substrate particles and a coating disposed over at least a portion of the substrate particles. The coating includes a condensation reaction product of a reaction mixture that includes a liquid isocyanate-functional component and an isocyanate-reactive composition. Also disclosed are methods for making such particles and methods for using such particles as proppants in hydraulic fracturing.
Claims18
A method of making coated particles comprising:
- (1) drying uncoated substrate particles having a particle size of no more than 3 mesh by heating the uncoated substrate particles to a temperature of at least 50° C. to produce dried uncoated substrate particles,
- (2) adding a coupling agent to the dried uncoated substrate particles,
- (3) adding a first reaction mixture comprising an isocyanate-reactive composition and a liquid isocyanate-functional component to a mixture resulting from step (2),
- (4) allowing a condensation reaction between the isocyanate-reactive composition and the liquid isocyanate-functional component to take place to form coated particles,
- (5) mixing the coated particles with a second reaction mixture comprising the isocyanate-reactive composition and the isocyanate-functional component, and
- (6) allowing a condensation reaction between the isocyanate-reactive composition and the isocyanate-functional component to take place to further coat the coated particles to form additionally coated particles,
- wherein the isocyanate-reactive composition comprises:
- (A) a plant oil polyester polyol;
- (B) an aromatic diamine;
- and
- (C) a catalyst for the reaction between hydroxyl groups and isocyanate groups,
- wherein the plant oil polyester polyol is present in an amount of at least 60% by weight, based on the total weight of isocyanate-reactive components present in the isocyanate-reactive composition and the aromatic diamine is present in an amount of 10 to 40% by weight, based on the total weight of the total weight of isocyanate-reactive components present in the isocyanate-reactive composition.
9 more elements
A method of making coated particles comprising:
- (1) mixing substrate particles having a particle size of no more than 3 mesh with a first reaction mixture comprising an isocyanate-reactive composition and a liquid isocyanate-functional component,
- (2) allowing a condensation reaction between the isocyanate-reactive composition and the liquid isocyanate-functional component to take place to form coated particles,
- (3) mixing the coated particles with a second reaction mixture comprising the isocyanate-reactive composition and the isocyanate-functional component;
- and
- (4) allowing a condensation reaction between the isocyanate-reactive composition and the isocyanate-functional component to take place to further coat the coated particles to form additionally coated particles,
- wherein the isocyanate-reactive composition comprises:
- (A) a plant oil polyester polyol;
- (B) an aromatic diamine;
- and
- (C) a catalyst for the reaction between hydroxyl groups and isocyanate groups,
- wherein the plant oil polyester polyol is present in an amount of at least 60% by weight, based on the total weight of isocyanate-reactive components present in the isocyanate-reactive composition and the aromatic diamine is present in an amount of 10 to 40% by weight, based on the total weight of the total weight of isocyanate-reactive components present in the isocyanate-reactive composition,
- wherein the total reaction mixture used is 0.1% to 10% by weight, based on the total weight of substrate particles.
9 more elements
A method of making coated particles comprising:
- (1) mixing substrate particles having a particle size of no more than 3 mesh with a first reaction mixture comprising an isocyanate-reactive composition and a liquid isocyanate-functional component,
- (2) allowing a condensation reaction between the isocyanate-reactive composition and the liquid isocyanate-functional component to take place to form coated particles,
- (3) mixing the coated particles with a second reaction mixture comprising the isocyanate-reactive composition and the isocyanate-functional component,
- (4) allowing a condensation reaction between the isocyanate-reactive composition and the isocyanate-functional component to take place to further coat the coated particles to form additionally coated particles,
- wherein the isocyanate-reactive composition comprises:
- (A) a plant oil polyester polyol;
- (B) an aromatic diamine;
- and
- (C) a catalyst for the reaction between hydroxyl groups and isocyanate groups,
- wherein the plant oil polyester polyol is present in an amount of at least 60% by weight, based on the total weight of isocyanate-reactive components present in the isocyanate-reactive composition and the aromatic diamine is present in an amount of 10 to 40% by weight, based on the total weight of the total weight of isocyanate-reactive components present in the isocyanate-reactive composition, and
- (5) adding an aqueous dispersion of a crystalline or semicrystalline polyester/polyurethane to the additionally coated particles,
- wherein the aqueous dispersion of a crystalline or semicrystalline polyester/polyurethane is added in an amount such that the crystalline or semicrystalline polyester/polyurethane is present in an amount of 0.01 to 1% by weight, based on the total weight of the additionally coated particles.
9 more elements
Dependencies are inferred from the claim text.