Method of forming composite fiber blends and molding same

• US 4,799,985 A
• Filed: 04/28/1986
• Issued: 01/24/1989
• Est. Priority Date: 03/15/1984
• Status: Expired due to Fees

• Current Assignee: Cytec Technology Corp. (Syensqo SA)
• Original Assignee: Hoechst Celanese Corporation (Sanofi )
• Inventors: Chung, Tai-Shung, McMahon, Paul E.
• Primary Examiner(s): Ball, Michael
• Application Number:
  US06/858,903
• Time in Patent Office: 1,002 Days
• Field of Search: 28/282, 28/103, 28/283, 28/216, 28/274, 57/908, 264/257, 264/258, 156/245, 156/175, 156/166, 156/180, 156/181, 156/309.6, 156/167, 19/299, 19/145.5, 19/66 T, 19/65 T, 428/364, 428/288, 428/296
• US Class Current: 156/166
• CPC Class Codes: D02G 3/402 the adhesive being one component of the yarn, i.e. thermoplastic yarn
• CPC Class Codes: D02G 3/447 Yarns or threads for specific use in general industrial applications, e.g. as filters or reinforcement

Abstract

The instant invention involves a process used in preparing fibrous tows which may be formed into polymeric plastic composites. The process involves the steps of (a) forming a tow of strong filamentary materials; (b) forming a thermoplastic polymeric fiber; (c) intermixing the two tows; and (d) withdrawing the intermixed tow for further use.

Claims

1. A process for preparing a composite article which comprises:

(a) forming a continuous tow of continuous non-thermoplastic reinforcing fibers;

(b) forming a continuous tow of continuous thermoplastic polymer fibers having a melting point of at least about 50°

C.;

(c) uniformly and continuously spreading the thermoplastic polymer fiber tow to a selected width;

(d) uniformly and continuously spreading the non-thermoplastic reinforcing fiber tow to a width that is essentially the same as the selected width for the thermoplastic polymer fiber tow;

(e) intimately, uniformly and continuously intermixing the spread non-thermoplastic reinforcing fiber tow and the spread thermoplastic polymer fiber tow in a relatively tension-free state by employing a gas intermixing means which directs a generally perpendicular gas flow onto the fibers and by bringing the tows into simultaneous contact with each other in substantially the same area such that there is provided a substantially uniform distribution of the thermoplastic fibers and the non-thermoplastic reinforcing fibers within an intimately intermixed tow;

(f) continuously withdrawing the intimately intermixed tow;

(g) applying the intimately intermixed tow to a mold; and

(h) heating the intermixed tow to a temperature above the melting point of the thermoplastic fibers.

3. The process of claims 1 or 2 wherein the reinforcing fibers are formed from the group consisting of metallic, ceramic, amorphous, and polycrystalline fibers.

4. The process of claim 3 wherein the reinforcing fibers are formed from glass, boron or ceramic fibers.

5. The process of claims 1 or 2 wherein the tow of reinforcing fibers has a bundle denier of about 100 to 100,000.

6. The process of claims 1 or 2 wherein the tow of reinforcing fibers has a bundle denier of about 1,000 to 16,000.

7. The process of claims 1 or 2 wherein the tow of reinforcing fibers contains about 100 to 300,000 filaments.

8. The process of claims 1 or 2 wherein the two of reinforcing fibers contains about 3,000 to 24,000 filaments.

9. The process of claims 1 or 2 wherein the thermoplastic polymer fibers are selected from the group consisting of polyethylene, polypropylene, polyesters, nylons, polyamidimides, polyetherimides, polysulfones, polyether ether ketones and wholly aromatic polyester resins.

10. The process of claims 1 or 2 wherein the thermoplastic polymer fibers are liquid crystal polymer fibers.

11. The process of claims 1 or 2 wherein the thermoplastic polymer fibers are wholly aromatic polyester fibers.

12. The process of claims 1 or 2 wherein the denier of the individual thermoplastic fibers is in the range of about 1 to about 50 and wherein the tow of thermoplastic fibers contains from about 10 to about 150,000 filaments.

13. The process of claims 1 or 2 wherein the intimately intermixed tow contains about 10 to about 70 percent by volume of non-thermoplastic reinforcing fibers.

14. The process of claim 13 wherein the intimately intermixed tow contains about 20 to about 60 percent by volume of non-thermoplastic reinforcing fibers.

15. The process of claim 14 wherein the intermixed tow contains about 60 percent by volume of non-thermoplastic reinforcing fibers.

16. The process of claims 1 or 2 wherein the intimately intermixed tow is continuously applied to a mold employing a filament winding process.

17. The process of claims 1 or 2 wherein the intimately intermixed tow is applied to a mold in the form of a woven fabric.

18. The process of claims 1 or 2 wherein the composite article is a recreational article.

19. The process of claim 18 wherein the composite article is a tennis racquet frame.

2. A process for preparing a composite article which comprises:

(a) forming a continuous tow of continuous non-thermoplastic reinforcing fibers;

(b) forming a continuous tow of continuous thermoplastic polymer fibers having a melting point of at least about 50°

C.;

(c) uniformly and continuously spreading the thermoplastic polymer fiber tow to a selected width;

(d) uniformly and continuously spreading the non-thermoplastic reinforcing fiber tow to a width that is essentially the same as the selected width for the thermoplastic polymer fiber tow;

(e) intimately, uniformly and continuously intermixing the spread non-thermoplastic reinforcing fiber tow and the spread thermoplastic polymer fiber tow in a relatively tension-free state by employing a gas box which directs a generally perpendicular gas flow onto the fibers and by bringing the tows into simultaneous contact with each other in substantially the same area such that there is provided a substantially uniform distribution of the thermoplastic fibers and the non-thermoplastic reinforcing fibers within an intimately intermixed tow;

(f) continuously withdrawing the intimately intermixed tow;

(g) applying the intimately intermixed tow to a mold; and

(h) heating the intermixed tow to a temperature above the melting point of the thermoplastic fibers.