WO1986003449A1 - Impregnating fibres reinforcement with polymer materials - Google Patents

Impregnating fibres reinforcement with polymer materials Download PDF

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Publication number
WO1986003449A1
WO1986003449A1 PCT/GB1985/000558 GB8500558W WO8603449A1 WO 1986003449 A1 WO1986003449 A1 WO 1986003449A1 GB 8500558 W GB8500558 W GB 8500558W WO 8603449 A1 WO8603449 A1 WO 8603449A1
Authority
WO
WIPO (PCT)
Prior art keywords
polymer material
fibres
reinforcement
impregnating
fibres reinforcement
Prior art date
Application number
PCT/GB1985/000558
Other languages
French (fr)
Inventor
Peter John Ives
Original Assignee
H R Smith (Technical Developments) Limited
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by H R Smith (Technical Developments) Limited filed Critical H R Smith (Technical Developments) Limited
Publication of WO1986003449A1 publication Critical patent/WO1986003449A1/en

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
    • C08J5/04—Reinforcing macromolecular compounds with loose or coherent fibrous material

Definitions

  • the invention concerns the impregnation of fibres reinforcement with polymer material.
  • fibres reinfor ⁇ cement encompasses filaments, fibres or tows of filaments 01 fibres, mats of filaments or fibres or cloths prepared by weaving, knitting, laying-up or the like such filaments, fibres or tows, for use as reinforcement of a polymer mate ⁇ rial.
  • thermosetting polymer material with fibres reinforcement to form articles is more extensive than the use of fibres reinforced thermoplastics materials despite the fact that the advantages of using a thermoplastics material are well known.
  • the known precursors tend to be inflexible and difficult to handle in moulding processes - the stiffness of the impregnated fibres reinforcement making them difficult to drape - that is to say difficult to conform to the shape of any mould in which they are placed.
  • One aspect of the invention provides a method of impregnating fibres reinforcement with polymer material 25 including the steps of: mixing the polymer material in • particle form with a liquid in which the polymer material does not dissolve to form a dispersion; and impregnating the fibres reinforcement with the dispersion.
  • the polymer material is a thermoplastics material and the dispersent therfor has a boiling point below the glass transition temperature of the thermoplastics material.
  • the polymer material may be an aromatic polymer material selected from the group comprising: polysulphone, polyethersulphone, polyetheretherketone, polyetherketone, polyetherimide, polystyrene, polyphenelene sulphide and a polyamide.
  • the dispersent is water.
  • the oarti ⁇ le size of the polymer material is
  • a second aspect of the invention provides a reinforced polymer material made in accordance with of any of the methods noted above.
  • a third aspect of the invention provides an article and/or structure made from a fibres reinforced polymer material as noted above.
  • the impregnation of the fibres reinforcement in the liquid dispersent may be by immersion of the fibres rein ⁇ forcement therein with together, if necessary, mechanical agitation, kneading or the like.
  • Drying of the fibres reinforcement after impregnation may be effected by evaporarion at room temperature, median- ical drying or by heating to a temperature below the glass transition temperature of the polymer material.
  • the impregnated fibres reinfor- cement may be dried rapidly in an oven at a temperature below the glass transition temperature of the polymer o material - say 75 to 150 C if the polymer material is polyethersulphone.
  • the impregnated fibres reinforcement (either taken dir- ectly from the dispersion or after partial drying) may read ⁇ ily be laid up in a mould.
  • the liquid dispersent is not a solvent for the particular polymer material ⁇ the particles of polymer material in the fibre's reinforcement remain relatively mobile enabling the fibres reinforcement to be easily “draped” in a mould.
  • the impregnated fibres reinforcement be completely dry (that is to say with all the liquid dispersant driven off) it is possible for the impregnated fibres reinforcement to be re-wetted, e.g. by spraying with the dispersent, should it be necessary to enable it to be readily "draped”.
  • Pultrusion, filament winding spraying and impreg ⁇ nation of knitted or woven shapes may also readily be accom ⁇ plished with the present invention.
  • the dispersion of the polymer material may contain any thermosetting or thermoplastics material; however, we have found that the process is of particular advantage with polymer materials such as polysulphone, polyethersulphone, polyetheretherketone, polyetherketone, polyetherimide, poly ⁇ styrene, polyphenelene sulphide, polyamides or other thermo ⁇ plastics material obtainable in fine powder form.
  • polymer materials such as polysulphone, polyethersulphone, polyetheretherketone, polyetherketone, polyetherimide, poly ⁇ styrene, polyphenelene sulphide, polyamides or other thermo ⁇ plastics material obtainable in fine powder form.
  • water is described as the preferred dispersent it will be appreciated that any other liquid which is not a solvent for the polymer material may be used, for example, various different forms of Freeon may be used either alone or in combination.
  • the invention is of particular advantage when used with the particular polymer materials recited it will be appreciated that the methods described herein are utilisable with any polymer material having a particle size enabling it to form a dispersion and in that form be impregnated into fibres reinforcement.
  • the maximum particle size will, it will be appreciated, vary in accordance with the polymer used and the physical size of essential requirement is that the size of the majority of the particles be sufficiently small to permit the particles of the polymer to fully pass into the interstices of the fibres reinforcement.
  • all the polymer material be of a size enabling it to percolate between the fibres of the reinforcement, that is to say that all the particles in the dispersion be below the (critical) maximum • size for the fibres reinforcement being used - typically 5 Microns for commercially available glass, carbon or quartz fibres - however, in some appli ⁇ atons it is possible that a proportion of the polymer particles in the dispersion may be above that critical size - providing always that there are sufficient particles in the dispersion below that critical size to enable the fibres reinforcement to be impregnated to the level deired in the particular application under consideration.
  • the fibre's to be impregnated by the methods disclosed in this specification must not have been heavily pre-treated (e.g. sized) to an extent preventing the dispersion entering the interstices of the fibres. If in fact the fibres reinforcement have been so pre-treated it is necessary for them to be cleaned before they are impregnated by the methods disclosed herein.

Abstract

Method of impregnating fibres reinforcement with polymer material including the steps of: mixing the polymer material in particle form with a liquid in which the polymer material does not dissolve to form a dispersion; and impregnating the fibres reinforcement with the dispersion. The fibres reinforcement is said to be dried after impregnation with the dispersent. The use of the processes described with any polymer material is disclosed, however, the preferred polymers are said to be thermoplastics materials such as polysulphone, polyethersulphone, polyetheretherketone, polyetherketone, polyetherimide, polystyrene, polyphenelene suphide and polyamides. Any suitable liquid dispersant having a boiling point below the glass transition temperature of the thermoplastics material may be used and water is said to be preferred for the polymers enumerated. The particle size of the polymer used is said to vary in accordance with the characteristics of the fibres reinforcement used but a typical particle size not exceeding 5 microns is disclosed. The specification discloses in addition articles made from a fibres reinforced polymer material as described.

Description

IMPREGNATING FIBRES REINFORCEMENT WITH POLYMER
MATERIALS
DESCRIPTION
The invention concerns the impregnation of fibres reinforcement with polymer material.
Throughout this specification the term fibres reinfor¬ cement encompasses filaments, fibres or tows of filaments 01 fibres, mats of filaments or fibres or cloths prepared by weaving, knitting, laying-up or the like such filaments, fibres or tows, for use as reinforcement of a polymer mate¬ rial.
The use of thermosetting polymer material with fibres reinforcement to form articles is more extensive than the use of fibres reinforced thermoplastics materials despite the fact that the advantages of using a thermoplastics material are well known.
The production of a basic precursor (i.e. fibres rein- forcement impregnated with a thermoplastics material) from which a composite article can be made by moulding has proved difficult and costly (especially when the precursor must include 100% of the final desired polymer content). An extensively used way of impregnating fibres rein¬ forcement with a thermoplastics materials polymer material is to dissolve the polymer material and immerse the fibres reinforcement in the solution; after immersion the fibres 05 reinforcement is dried to drive off all (or a desired part) of the solvent leaving the fibres reinforcement impregnated with the polymer material (or a solution thereof). In using this process difficulties are met in ensuring that all (or the required amount) of the solvent is removed. The presence 10 of the solvent, even at very low levels can affect the ! * further processing of the material (for example leading to the formation of voids in the finished article) and can seriously alter the characteristics of the finished article (for example the strength of tfie article).
15 Again, the known precursors tend to be inflexible and difficult to handle in moulding processes - the stiffness of the impregnated fibres reinforcement making them difficult to drape - that is to say difficult to conform to the shape of any mould in which they are placed.
20 To meet these and other problems we now propose a novel method of impregnating fibres reinforcement with a polymer material in particular a thermoplastic polymer material.
One aspect of the invention provides a method of impregnating fibres reinforcement with polymer material 25 including the steps of: mixing the polymer material in • particle form with a liquid in which the polymer material does not dissolve to form a dispersion; and impregnating the fibres reinforcement with the dispersion.
With advantage the polymer material is a thermoplastics material and the dispersent therfor has a boiling point below the glass transition temperature of the thermoplastics material. The polymer material may be an aromatic polymer material selected from the group comprising: polysulphone, polyethersulphone, polyetheretherketone, polyetherketone, polyetherimide, polystyrene, polyphenelene sulphide and a polyamide.
Preferably the dispersent is water.
Desirably the oartiσle size of the polymer material is
*
5 microns or less.
A second aspect of the invention provides a reinforced polymer material made in accordance with of any of the methods noted above.
A third aspect of the invention provides an article and/or structure made from a fibres reinforced polymer material as noted above.
The impregnation of the fibres reinforcement in the liquid dispersent may be by immersion of the fibres rein¬ forcement therein with together, if necessary, mechanical agitation, kneading or the like.
Drying of the fibres reinforcement after impregnation may be effected by evaporarion at room temperature, median- ical drying or by heating to a temperature below the glass transition temperature of the polymer material. For example when the dispersent is water the impregnated fibres reinfor- cement may be dried rapidly in an oven at a temperature below the glass transition temperature of the polymer o material - say 75 to 150 C if the polymer material is polyethersulphone.
The impregnated fibres reinforcement (either taken dir- ectly from the dispersion or after partial drying) may read¬ ily be laid up in a mould. As the liquid dispersent is not a solvent for the particular polymer material^the particles of polymer material in the fibre's reinforcement remain relatively mobile enabling the fibres reinforcement to be easily "draped" in a mould. Should the impregnated fibres reinforcement be completely dry (that is to say with all the liquid dispersant driven off) it is possible for the impregnated fibres reinforcement to be re-wetted, e.g. by spraying with the dispersent, should it be necessary to enable it to be readily "draped".
An advantage of the process now described is that im- pregnated cloths or mats of fibres reinforcement may be draped on a former or shaper for use in a moulding process whilst wet. Further, it is possible for several layers of fabric to be laid up on top of one another to form complex double curvature shapes. Fibres reinforcement impregnated in the described process may be used in vacuum or positive pressure moulding processes.
Pultrusion, filament winding spraying and impreg¬ nation of knitted or woven shapes may also readily be accom¬ plished with the present invention.
The dispersion of the polymer material may contain any thermosetting or thermoplastics material; however, we have found that the process is of particular advantage with polymer materials such as polysulphone, polyethersulphone, polyetheretherketone, polyetherketone, polyetherimide, poly¬ styrene, polyphenelene sulphide, polyamides or other thermo¬ plastics material obtainable in fine powder form. *
Although water is described as the preferred dispersent it will be appreciated that any other liquid which is not a solvent for the polymer material may be used, for example, various different forms of Freeon may be used either alone or in combination.
Although as described the invention is of particular advantage when used with the particular polymer materials recited it will be appreciated that the methods described herein are utilisable with any polymer material having a particle size enabling it to form a dispersion and in that form be impregnated into fibres reinforcement. The maximum particle size will, it will be appreciated, vary in accordance with the polymer used and the physical size of essential requirement is that the size of the majority of the particles be sufficiently small to permit the particles of the polymer to fully pass into the interstices of the fibres reinforcement.
In normal cases it will be desired that all the polymer material be of a size enabling it to percolate between the fibres of the reinforcement, that is to say that all the particles in the dispersion be below the (critical) maximum • size for the fibres reinforcement being used - typically 5 Microns for commercially available glass, carbon or quartz fibres - however, in some appliσatons it is possible that a proportion of the polymer particles in the dispersion may be above that critical size - providing always that there are sufficient particles in the dispersion below that critical size to enable the fibres reinforcement to be impregnated to the level deired in the particular application under consideration.
It will also be appreciated that the fibre's to be impregnated by the methods disclosed in this specification must not have been heavily pre-treated (e.g. sized) to an extent preventing the dispersion entering the interstices of the fibres. If in fact the fibres reinforcement have been so pre-treated it is necessary for them to be cleaned before they are impregnated by the methods disclosed herein.
It will be appreciated that the process now described may be modified by the incorporation in the dispersion (and therefore in the finished product) of other desired particles and elements, such as blowing agents, pigments, other additives and/or fillers having decorative and/or functional characteristics in the final product.

Claims

1. A method of impregnating fibres reinforcement with polymer material including the steps of: mixing the polymer material in particle form with a liquid in which the polymer material does not dissolve to form a dispersion; and impregnating the fibres reinforcement with the dispersion.
2. A method as claimed in claim 1 , wherein the fibres reinforcement is at least partially dried after impregnation with the dispersent.
3. A method as claimed in claim 1 or claim 2, wherein the polymer material is a thermoplastics material and the dispersent therfor has a boiling point below the glass » transition temperature of the thermoplastics material.
4. A method as claimed in claim 1 , claim 2 or claim 3, wherein the polymer material is selected from the group comprising polysulphone, polyethersulphone, polyetherether- ketone, polyetherketone, polyetherimide, polystyrene, polyphenelene sulphide and a polyamide.
5. A method as claimed in any one of the preceeding claims wherein the dispersent is water.
6. A method as claimed in any one of the preceeding claim wherein the particle size of the polymer material is 5 microns or less.
7. A method of impregnating fibres reinforcement with a polymer material as claimed in claim 1 and substantially as herein described.
8. A fibres reinforced polymer material made in accordance with the method of any one of the preceeding claims.
9. An article made from a fibres reinforced polymer material as claimed in claim 8.
PCT/GB1985/000558 1984-12-07 1985-12-06 Impregnating fibres reinforcement with polymer materials WO1986003449A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB8430949 1984-12-07
GB848430949A GB8430949D0 (en) 1984-12-07 1984-12-07 Impregnating fibre reinforcements

Publications (1)

Publication Number Publication Date
WO1986003449A1 true WO1986003449A1 (en) 1986-06-19

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Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB1985/000558 WO1986003449A1 (en) 1984-12-07 1985-12-06 Impregnating fibres reinforcement with polymer materials

Country Status (4)

Country Link
EP (1) EP0203985A1 (en)
AU (1) AU5235686A (en)
GB (2) GB8430949D0 (en)
WO (1) WO1986003449A1 (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0316681A2 (en) * 1987-11-14 1989-05-24 BASF Aktiengesellschaft Fibre-renforced composite materials
US4894105A (en) * 1986-11-07 1990-01-16 Basf Aktiengesellschaft Production of improved preimpregnated material comprising a particulate thermoplastic polymer suitable for use in the formation of substantially void-free fiber-reinforced composite article
US4919739A (en) * 1986-11-07 1990-04-24 Basf Aktiengesellschaft Production of improved preimpregnated material comprising a particulate thermosetting resin suitable for use in the formation of a substantially void-free fiber-reinforced composite article
US4943472A (en) * 1988-03-03 1990-07-24 Basf Aktiengesellschaft Improved preimpregnated material comprising a particulate thermosetting resin suitable for use in the formation of a substantially void-free fiber-reinforced composite article
US5128198A (en) * 1986-11-07 1992-07-07 Basf Aktiengesellschaft Production of improved preimpregnated material comprising a particulate thermoplastic polymer suitable for use in the formation of a substantially void-free fiber-reinforced composite article
US6616971B2 (en) 1998-06-08 2003-09-09 Complastik Corporation Composite articles including prepregs, preforms, laminates and sandwich moldings, and methods of making the same
US6861131B2 (en) 2000-12-06 2005-03-01 Complastik Corp. Hybrid composite articles and methods for their production

Families Citing this family (9)

* Cited by examiner, † Cited by third party
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EP0209391A3 (en) * 1985-07-17 1988-08-31 Sumitomo Chemical Company, Limited Resin composition and circuit board moulded from the same
US4792481A (en) * 1986-11-28 1988-12-20 Phillips Petroleum Company Reinforced plastic
DE3750609T2 (en) * 1986-12-20 1995-03-23 Toho Rayon Kk Process for producing a carbon fiber reinforced thermoplastic resin article.
EP0275382A1 (en) * 1986-12-22 1988-07-27 General Electric Company Method for preparing composite felt preforms
NL8802768A (en) * 1988-11-10 1990-06-01 Stamicarbon METHOD FOR MANUFACTURING FLEXIBLE POLYMERS IMPROVED REINFORCEMENT MATERIALS, MANUFACTURED POLYMERS IMPROVED REINFORCEMENT MATERIALS, AND PREPARED MADE ON THESE REINFORCEMENT MATERIALS
BE1005106A3 (en) * 1991-07-16 1993-04-20 Dsm Nv PROCESS FOR MAKING A MATERIAL BY VOORGEIMPREGNEERD impregnating a fibrous reinforcement with a dispersion.
US5480603A (en) * 1994-05-19 1996-01-02 The Dow Chemical Company Method for preparing preforms for molding processes
US9855680B2 (en) 2013-06-11 2018-01-02 Johns Manville Fiber-reinforced composite articles and methods of making them
US20180186951A1 (en) * 2015-06-30 2018-07-05 Sabic Global Technologies B.V. Methods of manufacture of prepregs and composites from polyimide particles, and articles prepared therefrom

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FR2223173A1 (en) * 1973-03-28 1974-10-25 Kureha Chemical Ind Co Ltd
EP0013244A1 (en) * 1978-12-28 1980-07-09 Union Carbide Corporation Method of impregnating a fibrous textile material with a plastic resin
WO1983001755A1 (en) * 1981-11-18 1983-05-26 Chabrier, Gilbert Method for the manufacture of sections made of fiber-containing thermoplastic resin, installation for the implementation thereof and sections obtained thereby
US4402780A (en) * 1981-04-27 1983-09-06 Hiroyuki Ogoe Process for preparing laminates with thermoplastic resins
EP0102711A2 (en) * 1982-07-28 1984-03-14 Imperial Chemical Industries Plc Process for producing fibre-reinforced polymer compositions
EP0134973A2 (en) * 1983-07-12 1985-03-27 Phillips Petroleum Company Stampable sheets of fiber mat reinforced poly(arylene sulfide) and method of preparation

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GB439884A (en) * 1934-06-07 1935-12-09 Deutsche Celluloid Fabrik Manufacture of textile fabrics coated or impregnated with polymerisation products
US3632366A (en) * 1968-01-11 1972-01-04 Asahi Glass Co Ltd Method of producing moldable reinforced thermoplastic material
US4163742A (en) * 1978-02-09 1979-08-07 E. I. Du Pont De Nemours And Company Process and product prepared from tetrafluoroethylene resin and graphite fibers

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2223173A1 (en) * 1973-03-28 1974-10-25 Kureha Chemical Ind Co Ltd
EP0013244A1 (en) * 1978-12-28 1980-07-09 Union Carbide Corporation Method of impregnating a fibrous textile material with a plastic resin
US4402780A (en) * 1981-04-27 1983-09-06 Hiroyuki Ogoe Process for preparing laminates with thermoplastic resins
WO1983001755A1 (en) * 1981-11-18 1983-05-26 Chabrier, Gilbert Method for the manufacture of sections made of fiber-containing thermoplastic resin, installation for the implementation thereof and sections obtained thereby
EP0102711A2 (en) * 1982-07-28 1984-03-14 Imperial Chemical Industries Plc Process for producing fibre-reinforced polymer compositions
EP0134973A2 (en) * 1983-07-12 1985-03-27 Phillips Petroleum Company Stampable sheets of fiber mat reinforced poly(arylene sulfide) and method of preparation

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4894105A (en) * 1986-11-07 1990-01-16 Basf Aktiengesellschaft Production of improved preimpregnated material comprising a particulate thermoplastic polymer suitable for use in the formation of substantially void-free fiber-reinforced composite article
US4919739A (en) * 1986-11-07 1990-04-24 Basf Aktiengesellschaft Production of improved preimpregnated material comprising a particulate thermosetting resin suitable for use in the formation of a substantially void-free fiber-reinforced composite article
US5128198A (en) * 1986-11-07 1992-07-07 Basf Aktiengesellschaft Production of improved preimpregnated material comprising a particulate thermoplastic polymer suitable for use in the formation of a substantially void-free fiber-reinforced composite article
EP0316681A2 (en) * 1987-11-14 1989-05-24 BASF Aktiengesellschaft Fibre-renforced composite materials
EP0316681A3 (en) * 1987-11-14 1989-11-02 BASF Aktiengesellschaft Fibre-renforced composite materials
US4943472A (en) * 1988-03-03 1990-07-24 Basf Aktiengesellschaft Improved preimpregnated material comprising a particulate thermosetting resin suitable for use in the formation of a substantially void-free fiber-reinforced composite article
US6616971B2 (en) 1998-06-08 2003-09-09 Complastik Corporation Composite articles including prepregs, preforms, laminates and sandwich moldings, and methods of making the same
US6861131B2 (en) 2000-12-06 2005-03-01 Complastik Corp. Hybrid composite articles and methods for their production

Also Published As

Publication number Publication date
AU5235686A (en) 1986-07-01
GB8430949D0 (en) 1985-01-16
GB8530124D0 (en) 1986-01-15
EP0203985A1 (en) 1986-12-10
GB2168361A (en) 1986-06-18

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