Solid composites containing polymeric matrix with carbon fibers embedded therein

• US 10,501,590 B2
• Filed: 05/18/2016
• Issued: 12/10/2019
• Est. Priority Date: 02/28/2012
• Status: Active Grant

• Current Assignee: UT-Battelle LLC
• Original Assignee: UT-Battelle LLC
• Inventors: Vautard, Frederic, Ozcan, Soydan, Paulauskas, Felix Leonard
• Primary Examiner(s): Thompson, Camie S
• Application Number:
  US15/158,012
• Publication Number:
  US 20160312024A1
• Time in Patent Office: 1,301 Days
• Field of Search: 4272071, 4283001, 428403, 428359, 428368, 428375, 428378
• CPC Class Codes: C08J 2333/04 esters
• CPC Class Codes: C08J 2363/00 Characterised by the use of epoxy resins; Derivatives of epoxy resins
• CPC Class Codes: C08J 2463/00 Characterised by the use of epoxy resins; Derivatives of epoxy resins
• CPC Class Codes: C08J 5/06 using pretreated fibrous materials
• CPC Class Codes: C08L 63/10 Epoxy resins modified by unsaturated compounds
• CPC Class Codes: Y10T 428/249948 Fiber is precoated
• CPC Class Codes: Y10T 428/2918 including free carbon or carbide or therewith [not as steel]

Abstract

A functionalized carbon fiber having covalently bound on its surface a partially cured epoxy or amine-containing sizing agent, wherein at least a portion of epoxide or amine groups in the sizing agent are available as uncrosslinked epoxide or amine groups, which corresponds to a curing degree of epoxide or amine groups of no more than about 0.6. Composites comprised of these functionalized carbon fibers embedded in a polymeric matrix are also described. Methods for producing the functionalized carbon fibers and composites thereof are also described.

Claims

1. A solid composite in which carbon fibers are embedded in a polymeric matrix derived from an unsaturated precursor resin containing carbon-carbon double bonds, wherein said carbon fibers have covalently bonded on their surfaces a partially cured sizing agent comprised of an epoxy resin, wherein said epoxy resin is covalently attached to a linking group that contains an accessible unsaturated group capable of reacting with said carbon-carbon double bonds via a vinyl addition reaction, and at least a portion of epoxide groups in the sizing agent are available as uncrosslinked epoxide groups, which corresponds to a curing degree of epoxide groups of no more than about 0.6.

2. The solid composite of claim 1, wherein said polymeric matrix is a thermoset.

3. The solid composite of claim 2, wherein said thermoset is derived from vinyl-addition polymerization of an unsaturated resin containing carbon-carbon double bonds.

4. The solid composite of claim 3, wherein said unsaturated resin is a vinyl ester resin.

5. The solid composite of claim 3, wherein said unsaturated resin is an unsaturated polyester resin.

6. The solid composite of claim 3, wherein said unsaturated resin is in admixture with at least one unsaturated reactive diluent that is cured with the unsaturated resin.

7. The solid composite of claim 6, wherein said unsaturated reactive diluent is selected from the group consisting of styrene, divinyl benzenes, methacrylates, acrylates, and vinyl esters.

8. The solid composite of claim 1, wherein said polymeric matrix is derived from an acrylate or methacrylate resin.

9. The solid composite of claim 1, wherein said polymeric matrix is a thermoplastic.

10. The solid composite of claim 1, wherein said epoxy resin possesses a curing degree of surface epoxide groups of no more than about 0.5.

11. The solid composite of claim 1, wherein said epoxy resin possesses a curing degree of surface epoxide groups of no more than about 0.4.

12. The solid composite of claim 1, wherein said epoxy resin is comprised of a difunctional epoxy resin.

13. The solid composite of claim 12, wherein said difunctional epoxy resin is selected from one or both of bisphenol A diglycidyl ether and ethylene glycol diglycidyl ether.

14. The solid composite of claim 1, wherein said epoxy resin is trifunctional or a higher functional epoxy resin.

15. The solid composite of claim 1, wherein said partially cured sizing agent is a flexible gel.

16. A solid composite in which carbon fibers are embedded in a polymeric matrix derived from an unsaturated precursor resin containing carbon-carbon double bonds, wherein said carbon fibers have covalently bonded on their surfaces a partially cured amine-containing sizing agent, wherein said amine-containing sizing agent is covalently attached to a linking group that contains an accessible unsaturated group capable of reacting with said carbon-carbon double bonds via a vinyl addition reaction, and at least a portion of amine groups in the sizing agent are available as uncrosslinked amine groups, which corresponds to a curing degree of amine groups of no more than about 0.6.

17. The solid composite of claim 16, wherein said polymeric matrix is a thermoset.

18. The solid composite of claim 17, wherein said thermoset is an acrylate resin, vinyl ester resin, or polyester resin that covalently bonds with amine groups of the amine-containing sizing agent.

19. The solid composite of claim 18, wherein said resin is an acrylate, a vinyl sulfone, a vinyl ester, a polyester, or an unsaturated resin containing an acrylate monomer or a vinyl ester monomer in admixture with at least one unsaturated reactive diluent.

20. The solid composite of claim 19, wherein said unsaturated reactive diluent is selected from the group consisting of styrene, divinyl benzenes, methacrylates, and vinyl esters.

21. The solid composite of claim 16, wherein said polymeric matrix is a thermoplastic derived from a monomer containing a functionality that covalently bonds with the uncrosslinked amine groups of the sizing agent.

22. The solid composite of claim 21, wherein said functionality is selected from an ester, a carboxylic acid, a urethane, an aldehyde, and a ketone.