Method of prepregging with resin and novel prepregs produced by such method

• US 6,524,690 B1
• Filed: 02/19/1999
• Issued: 02/25/2003
• Est. Priority Date: 07/09/1997
• Status: Expired due to Term

• Current Assignee: Polycom Incorporated (Plantronics, Inc.)
• Original Assignee: Balmer R. Charles, Joel A. Dyksterhouse
• Inventors: Dyksterhouse, Joel A.
• Primary Examiner(s): Cain, Edward J.
• Application Number:
  US09/253,805
• Time in Patent Office: 1,467 Days
• Field of Search: 156/189, 156/273.9, 156/309.6, 156/325, 264/258, 264/324, 264/136, 264/137, 264/145, 264/171.13, 428/221
• US Class Current: 428/221
• CPC Class Codes: B29B 15/122 with a matrix in liquid form, e.g. as melt, solution or latex
• CPC Class Codes: B29B 15/125 by dipping
• CPC Class Codes: Y10T 428/249921 Web or sheet containing structurally defined element or component
• CPC Class Codes: Y10T 442/603 Including strand or fiber material precoated with other than free metal or alloy
• CPC Class Codes: Y10T 442/604 Strand or fiber material is glass
• CPC Class Codes: Y10T 442/607 Strand or fiber material is synthetic polymer
• CPC Class Codes: Y10T 442/643 Including parallel strand or fiber material within the nonwoven fabric
• CPC Class Codes: Y10T 442/644 Parallel strand or fiber material is glass

Abstract

Disclosed is a process of forming a prepreg material having substantially no voids. According to the process of the invention, the reinforcing material is heated to a temperature above the temperature of the impregnating resin. The prepreg formed has substantially no voids and does not require lengthy consolidation when formed into useful articles.

Claims

1. An apparatus for preparing a reinforced matrix resin composition, comprising a heater for heating a fibrous reinforcing material to a first temperature and a container having an inlet and an outlet for the heated fibrous reinforcing material in which the heated reinforcing material is contacted with a molten resin composition;

wherein the first temperature, as measured at said inlet, is above the temperature of the resin composition.

2. An apparatus according to claim 1, further comprising a shearing mechanism for applying shear to the fibrous reinforcing material when the fibrous reinforcing material is in the container.

3. An apparatus according to claim 1, wherein said container further comprises a unit for applying pressure to the resin composition.

4. An apparatus according to claim 1, wherein said outlet is a sizing die.

5. An apparatus according to claim 1, further including molding equipment for forming the reinforced matrix resin composition into an article of a desired shape.

6. An apparatus for preparing a reinforced matrix resin composition, comprising

a heater for heating a fibrous reinforcing material;

and

a compressing unit for pressing the heated fibrous reinforcing material together with a resin composition;

wherein the heater is located so that the heated fibrous reinforcing material is provided to the compressing unit at a temperature that is sufficient to produce a prepreg having substantially no voids.

7. An apparatus according to claim 6, wherein the compressing unit is at least one pair of compaction rollers.

8. An apparatus according to claim 6, further comprising a sizing die located after said compressing unit.

9. An apparatus according to claim 6, further including molding equipment for forming the reinforced matrix resin composition into an article of a desired shape.