Curable fiber
Fibers comprising a first thermoplastic composition having a softening temperature up to 120° C and a curable resin. Also disclosed are compositions comprising a plurality of fibers, with some of the fibers comprising a first thermoplastic composition having a softening temperature up to 120° C and some of the fibers comprising a curable resin. The fibers have an aspect ratio of at least 2:1 and a maximum cross-sectional dimension up to 60 micrometers. Fluid compositions containing the fibers and methods of contacting a subterranean formation using the fibers are also disclosed.
1. A fiber comprising:
a first thermoplastic composition, and
a curable resin,
wherein an admixture of the first thermoplastic composition and the curable resin forms at least a portion of the fiber, wherein the admixture has a softening temperature up to 120° C., wherein the fiber has an aspect ratio of at least 2:1, and wherein the fiber has a maximum cross-sectional dimension up to 60 micrometers.
2. The fiber according to claim 1 , wherein the softening temperature of the first thermoplastic composition is within 20° C. of a cure onset temperature of the curable resin.
3. The fiber according to claim 1 , wherein the first thermoplastic composition includes a thermoplastic with functional groups that can react with or cause the homopolymerization of the curable resin.
4. The fiber according to claim 1 , wherein the first thermoplastic composition comprises at least one of an ethylene-vinyl alcohol copolymer, an at least partially neutralized ethylene-methacrylic acid or ethylene-acrylic acid copolymer, polyurethane, polyoxymethylene, polypropylene, polyolefin, ethylene-vinyl acetate copolymer, polyester, polyamide, phenoxy, vinyl, or acrylic.
5. The fiber according to claim 1 , wherein the first thermoplastic composition comprises a curing agent.
6. A composition comprising a plurality of the fibers according to claim 1 and a fluid, wherein the plurality of fibers is dispersed in the fluid, and wherein the composition optionally further comprises proppants dispersed in the fluid.
7. A method of treating a subterranean formation, the method comprising:
injecting into a well-bore intersecting the subterranean formation the composition according to claim 6 ;
exposing the first thermoplastic composition to at least one temperature above the softening temperature; and
at least partially curing the curable resin.
8. The fiber according to claim 1 , wherein the curable resin comprises at least one of an epoxy, phenolic, acrylic, isocyanate, phenoxy, vinyl, vinyl ether, or silane.
9. The fiber according to claim 8 , wherein the curable resin comprises a solid epoxy resin.
10. The fiber according to claim 1 , comprising a core and a sheath surrounding the core, wherein the core comprises a second thermoplastic composition having a melting point of at least 140° C., and wherein the sheath comprises the first thermoplastic composition and the curable resin.
11. The fiber according to claim 10 , wherein the second thermoplastic composition comprises at least one of an ethylene-vinyl alcohol copolymer, polyamide, polyoxymethylene, polypropylene, polyester, polyurethane, polysulfone, polyimide, polyetheretherketone, or polycarbonate.
12. The fiber according to claim 10 , wherein the first thermoplastic composition comprises at least one of an ethylene-vinyl alcohol copolymer, an at least partially neutralized ethylene-methacrylic acid or ethylene-acrylic acid copolymer, polyurethane, polyoxymethylene, polypropylene, polyolefin, ethylene-vinyl acetate copolymer, polyester, polyamide, phenoxy, vinyl, or acrylic.
13. The fiber according to claim 10 , wherein the first thermoplastic composition comprises a curing agent.
14. The fiber according to claim 10 , wherein the curable resin comprises at least one of an epoxy, phenolic, acrylic, isocyanate, phenoxy, vinyl, vinyl ether, or silane.
15. The fiber according to claim 14 , wherein the curable resin comprises a solid epoxy resin.
16. A composition comprising a plurality of the fibers according to claim 10 .
17. The composition according to claim 16 , wherein at least some of the fibers comprise at least one surface applied surfactant or polymeric dispersing agent.
18. The composition according to claim 16 , further having at least one of the following features:
wherein when a 5 percent by weight mixture of the plurality of fibers in deionized water is heated at 145° C. for four hours in an autoclave, less than 50% by volume of the plurality of fibers at least one of dissolves or disintegrates, and less than 50% by volume of the first thermoplastic composition and the curable resin at least one of dissolves or disintegrates; or
wherein when a 2 percent weight to volume mixture of the plurality of fibers in kerosene is heated at 145° C. for 24 hours under nitrogen, less than 50% by volume of the plurality of fibers at least one of dissolves or disintegrates, and less than 50% by volume of the first thermoplastic composition and the curable resin at least one of dissolves or disintegrates.
19. The composition according to claim 16 , further comprising a fluid, wherein the plurality of fibers is dispersed in the fluid, and wherein the composition optionally further comprises proppants dispersed in the fluid.
20. A method of treating a subterranean formation, the method comprising:
injecting into a well-bore intersecting the subterranean formation the composition according to claim 19 ;
exposing the first thermoplastic composition to at least one temperature above the softening temperature; and
at least partially curing the curable resin.