Fiber-containing prepregs and methods and systems of making

Patent metadata

Field	Value
Publication number	US-11548245-B2
Application number	US-201314088034-A
Country	US
Kind code	B2
Filing date	Nov 22, 2013
Priority date	Nov 22, 2013
Publication date	Jan 10, 2023
Grant date	Jan 10, 2023

Abstract

Methods of making fiber-containing prepregs are described. The methods may include the steps of providing a plurality of fibers, and applying a reactive resin composition to the plurality of fibers to make a mixture of the plurality of fibers and the resin composition. The reactive resin composition may include at least one of monomers and oligomers capable of polymerizing into a polymerized resin matrix. The mixture may be heated to a polymerization temperature where the monomers, oligomers, or both polymerize to form a fiber-resin amalgam that includes the polymerized resin matrix. The fiber-resin amalgam may be formed into the fiber-containing prepreg. Also described are methods of forming a fiber-reinforced composite that includes the prepreg.

First claim

What is claimed is:

1. A method of making a fiber-containing thermoplastic prepreg, the method comprising:
providing a plurality of glass fibers arranged into a continuous, woven or non-woven, glass fiber mat;
applying a reactive resin composition dispensed from a sheet die onto the continuous, woven or non-woven, glass fiber mat to make a mixture of the continuous, woven or non-woven, glass fiber mat and the reactive resin composition, wherein the reactive resin composition comprises caprolactam monomers capable of polymerizing into a polymerized resin matrix, and wherein the reactive resin composition includes a polymerization agent that is found exclusively in the reactive resin composition;
heating the mixture to a polymerization temperature after the reactive resin composition has been applied onto the continuous, woven or non-woven, glass fiber mat, wherein the monomers polymerize to form a fiber-resin amalgam comprising the continuous, woven or non-woven, glass fiber mat and the polymerized resin matrix; and
cutting the fiber-resin amalgam into sheets and forming the fiber-containing thermoplastic prepreg;
wherein the reactive resin composition polymerizes into a polymerized resin matrix with a multi-modal distribution of melting points.

2. The method of claim 1 , wherein the polymerization agent comprises a polymerization catalyst.

3. The method of claim 1 , wherein the polymerized resin matrix comprises polyamide-6.

4. The method of claim 1 , wherein the reactive resin composition further comprises cyclic butylene terephthalate.

5. The method of claim 1 , wherein the polymerized resin matrix further comprises polybutylene terephthalate.

6. The method of claim 1 , wherein the step of applying the reactive resin composition dispensed from the sheet die onto the continuous, woven or non-woven, glass fiber mat comprises:
melting the reactive resin composition to form a melted reactive resin composition, wherein the reactive resin composition is melted at a melting temperature that is below the polymerization temperature; and
dispensing the melted reactive resin composition from the sheet die onto the continuous, woven or non-woven, glass fiber mat.

7. A method of making a fiber-reinforced composite, the method comprising:
providing a plurality of fibers arranged into a continuous, woven or non-woven, fiber mat;
applying a reactive resin composition dispensed from the sheet die onto the continuous, woven or non-woven, fiber mat to make a mixture of the continuous, woven or non-woven, fiber mat and the resin composition, wherein the reactive resin composition comprises caprolactam monomers capable of polymerizing into a polymerized resin matrix, and wherein the reactive resin composition includes a lactam salt polymerization agent that is found exclusively in the reactive resin composition;
heating the mixture to a polymerization temperature after the reactive resin composition has been applied onto the continuous, woven or non-woven, fiber mat, wherein the monomers polymerize to form a fiber-resin amalgam comprising the continuous, woven or non-woven, fiber mat and the polymerized resin matrix;
cutting the fiber-resin amalgam into sheets and forming the fiber-containing thermoplastic prepreg; and
forming the at least one fiber-containing thermoplastic prepreg into the fiber-reinforced composite;
wherein the reactive resin composition polymerizes into a polymerized resin matrix with a multi-modal distribution of melting points.

8. The method of claim 7 , wherein the forming of the at least one fiber-containing thermoplastic prepreg into the fiber-reinforced composite comprises:
applying the fiber-containing thermoplastic prepreg to a mold for the fiber-reinforced composite article; and
heating the fiber-containing thermoplastic prepreg in the mold to at least partially melt the polymerized resin matrix, wherein the melted polymerized resin matrix bonds the fiber-containing thermoplastic prepreg to adjacent regions of the fiber-reinforced composite article.

9. The method of claim 8 , wherein the method further comprises pressing the fiber-containing thermoplastic prepreg against the adjacent regions of the fiber-reinforced composite article.

10. The method of claim 7 , wherein the plurality of fibers arranged into a continuous, woven or non-woven, fiber mat comprises one or more kinds of glass fibers, carbon fibers, inorganic fibers, metal fibers, organic polymer fibers, or mineral fibers.

11. The method of claim 7 , wherein the step of applying the reactive resin composition dispensed from the sheet die onto the continuous, woven or non-woven, fiber mat comprises:
melting the reactive resin composition to form a melted reactive resin composition, wherein the reactive resin composition is melted at a melting temperature that is below the polymerization temperature; and
dispensing the melted reactive resin composition from the sheet die onto the continuous, woven or non-woven, fiber mat.

12. The method of claim 7 , wherein the lactam salt polymerization agent is selected from the group consisting of an alkali metal salt of caprolactam, an alkali-earth metal salt of caprolactam, and a Grignard salt of caprolactam.

13. The method of claim 7 , wherein the lactam salt polymerization agent comprises sodium caprolactam.

Assignees

• Johns Manville

Inventors

• Zhang Mingfu
• Gleich Klaus Friedrich
• Yohannes Asheber
• Block Michael J
• Asrar Jawed

Classifications

• C08L77/02

  Polyamides derived from omega-amino carboxylic acids or from lactams thereof (C08L77/10 takes precedence) · CPC title

• B05D3/0272

  with ovens · CPC title

• B29K2105/0872

  Prepregs · CPC title

• Y10T442/2992

  Coated or impregnated glass fiber fabric · CPC title

• B29B15/14

  of filaments or wires · CPC title