Flexible multiply towpreg tape from powder fusion coated towpreg

• US 5,409,757 A
• Filed: 11/10/1993
• Issued: 04/25/1995
• Est. Priority Date: 04/17/1989
• Status: Expired due to Term

• Current Assignee: Georgia Tech Research Corporation (University System of Georgia)
• Original Assignee: Georgia Tech Research Corporation (University System of Georgia)
• Inventors: Colton, Jonathan S., Muzzy, John D.
• Primary Examiner(s): Bell, James J.
• Application Number:
  US08/132,583
• Time in Patent Office: 531 Days
• Field of Search: 428/114, 428/294, 428/902, 428/332
• US Class Current: 428/114
• CPC Class Codes: B29B 15/12 of reinforcements of indefinite length
• CPC Class Codes: B29C 70/20 oriented in a single direction, e.g. roofing or other parallel fibres B29C70/083, B29C70/226 take precedence
• CPC Class Codes: B29C 70/50 for producing articles of indefinite length, e.g. prepregs, sheet moulding compounds [SMC] or cross moulding compounds [XMC]
• CPC Class Codes: B29C 70/504 using rollers or pressure bands for corrugating B29C53/22
• CPC Class Codes: B29K 2105/0067 Melt
• CPC Class Codes: B29K 2105/0088 Blends of polymers
• CPC Class Codes: B29K 2105/251 Particles, powder or granules expandable particles B29K2105/046
• CPC Class Codes: B29K 2105/26 Scrap or recycled material
• CPC Class Codes: C04B 41/4584 Coating or impregnating of particulate or fibrous ceramic material C04B20/10, C04B35/628 take precedence
• CPC Class Codes: D01F 11/14 with organic compounds, e.g. macromolecular compounds
• CPC Class Codes: D01F 11/16 by physicochemical methods
• CPC Class Codes: D06M 23/08 Processes in which the treating agent is applied in powder or granular form adhesives for multi-layer textile fabrics D06M17/00
• CPC Class Codes: Y10S 428/902 High modulus filament or fiber
• CPC Class Codes: Y10T 428/24132 including grain, strips, or filamentary elements in different layers or components parallel
• CPC Class Codes: Y10T 428/26 Web or sheet containing structurally defined element or component, the element or component having a specified physical dimension
• CPC Class Codes: Y10T 442/67 Multiple nonwoven fabric layers composed of the same inorganic strand or fiber material

Abstract

An improved flexible towpreg tape of a known geometry and a method of production therefor. The improved flexible towpreg tape is formed from a plurality of reinforcing filaments fusion coated with matrix forming material, the reinforcing filaments being substantially wet-out by the matrix forming material, and the towpreg tape having multiple plies with an average thickness less than about 100 microns. The method of production for the improved flexible towpreg tape includes the steps of coating the reinforcing filaments with the matrix forming material in a manner causing interfacial adhesion of the matrix forming material to the reinforcing filaments; forming a towpreg by heating the matrix forming material contacting the reinforcing filaments until the matrix forming material liquefies and coats the reinforcing filaments; and forming the towpreg tape under pressure and elevated temperature in a means for creating a known tape geometry.

Claims

1. An improved flexible towpreg tape of a known geometry comprising a plurality of towpreg plies, said towpreg plies comprising reinforcing filaments and matrix forming material;

said reinforcing filaments being substantially wet-out by said matrix forming material such that said towpreg plies have fewer voids than said towpreg tape, said towpreg plies having an average thickness less than 100 microns.

2. The improved flexible towpreg tape as claimed in claim 1, wherein said towpreg plies have an average thickness of between about 10 to 50 microns.

3. The improved flexible towpreg tape as claimed in claim 1, wherein said towpreg tape comprises a plurality of towpreg plies comprising said reinforcing filaments and said matrix forming material.

4. The improved flexible towpreg tape as claimed in claim 3, wherein said towpreg plies are connected to neighboring towpreg plies by a common reinforcing filament.

5. An improved flexible towpreg tape of a known geometry comprising reinforcing filaments and matrix forming material, produced by a process comprising the steps of:

(a) providing reinforcing filaments and matrix forming material;

(b) coating said reinforcing filaments with said matrix forming material;

(c) forming a fusion coated towpreg by heating said reinforcing filaments and said matrix forming material such that said matrix forming material contacting said reinforcing filaments liquifies and coats said reinforcing filaments; and

(d) subjecting said fusion coated towpreg to a forming force by passing said fusion coated towpreg through a forming means of known geometry, thus creating a fusion coated towpreg tape.