US4943472A
Expired / Lapsed
US
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Improved preimpregnated material comprising a particulate thermosetting resin suitable for use in the formation of a substantially void-free fiber-reinforced composite article
Assignee: Cytec Technology Corp
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Filing: 1989-10-25
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Granted: 1990-07-24
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Expires: 2009-10-25
Abstract
Abstract An improved multifilamentary fibrous material is formed having solid particles of a matrix-forming thermosetting resin substantially uniformly dispersed among adjoining filaments in the absence of fusion bonding. The thermosetting resin particles initially are dispersed in an aqueous medium containing an effective amount of a dissolved polymeric binding agent and the viscosity of the medium subsequently is substantially increased to at least 50,000 cps. to form a gelled impregnation bath having a plastic flow characteristic with shear-thinning behavior wherein the thermosetting resin particles are substantially uniformly suspended. The resulting impregnation bath is caused to flow between the adjoining filaments of the multifilamentary fibrous material with a concomitant viscosity reduction which aids in the incorporation of the resin particles. The concentration of the aqueous medium in the product is controlled to yield a uniform, handleable, drapable, tacky, and highly stable product. Upon the application of heat and pressure the improved product can be transformed into a fiber-reinforced composite article wherein the thermosetting resin forms the matrix phase.
Inventors
- 👤 Robert Dyksterhouse
- 👤 Joel A. Dyksterhouse
- 👤 Alan C. Handermann
- 👤 Edward D. Western
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 14:08
CPC Classifications
B; B29; B29B; B29B15/00; B29B15/08; B29B15/10; B29B15/12; B29K; B29K2105/00; B29K2105/0058; B29K2105/0064; B29K2105/25; B29K2105/251; Y; Y10; Y10S; Y10S428/00; Y10S428/902; Y10T; Y10T428/00; Y10T428/24; Y10T428/24058; Y10T428/24074; Y10T428/24116; Y10T428/24124; Y10T428/25; Y10T428/254; Y10T428/26; Y10T428/268; Y10T428/269; Y10T428/30; Y10T428/31504; Y10T428/31721; Y10T442/00; Y10T442/60; Y10T442/699
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
141 words
An improved preimpregnated fibrous material suitable for the formation of a fiber-reinforced composite article, said preimpregnated fibrous material comprising (a) a plurality of adjoining substantially parallel reinforcing filaments and, substantially uniformly dispersed between adjoining filaments in the absence of fusion bonding, (b) an effective amount of a polymeric water-soluble binding agent, (c) aqueous medium, and (d) solid particles of thermosetting resin, said (b), (c) and (d) having been derived from a dispersion having a viscosity specifically selected to provide a preimpregnated fibrous material which inherently (1) is drapable and tacky at ambient conditions, (2) is handleable without segregation of said particles within the fibrous material and (3) capable upon the application of heat and pressure of being transformed into a substantially void-free composite article of a predetermined configuration wherein said thermosetting resin is substantially completely cured and forms the matrix phase.
Claim 2
Dependent Claim
141 words
An improved preimpregnated fibrous material suitable for the formation of a fiber-reinforced composite article, said preimpregnated fibrous material comprising (a) a plurality of adjoining substantially parallel reinforcing filaments and, substantially uniformly dispersed between adjoining filaments in the absence of fusion bonding, (b) an effective amount of a polymeric water-soluble binding agent, (c) aqueous medium, and (d) solid particles of thermosetting resin, said (b), (c) and (d) having been derived from a dispersion having a viscosity specifically selected to provide a preimpregnated fibrous material which inherently (1) is drapable and tacky at ambient conditions, (2) is handleable without segregation of said particles within the fibrous material and (3) capable upon the application of heat and pressure of being transformed into a substantially void-free composite article of a predetermined configuration wherein said thermosetting resin is substantially completely cured and forms the matrix phase.
Claim 3
Dependent Claim
24 words
The improved fibrous material in accordance with claim 1 wherein said plurality of adjoining substantially parallel reinforcing filaments are provided as a single end.
Claim 4
Dependent Claim
27 words
The improved fibrous material in accordance with claim 1 wherein said fibrous material comprises a plurality of ends each comprising a plurality of substantially parallel reinforcing filaments.
Claim 5
Dependent Claim
35 words
The improved fibrous material in accordance with claim 1 wherein said fibrous material is in the configuration of a cloth which incorporates a plurality of ends each comprising a plurality of substantially parallel reinforcing filaments.
Claim 6
Dependent Claim
34 words
The improved fibrous material in accordance with claim 1 wherein said reinforcing filaments are selected from the group consisting of carbon, glass, aramid, silicon carbide, silicon nitride, boron nitride, and mixtures of the foregoing.
Claim 7
Dependent Claim
16 words
The improved fibrous material in accordance with claim 1 wherein said reinforcing filaments are carbon filaments.
Claim 8
Dependent Claim
16 words
The improved fibrous material in accordance with claim 1 wherein said reinforcing filaments are glass filaments.
Claim 9
Dependent Claim
53 words
The improved fibrous material in accordance with claim 1 wherein said solid particles of thermosetting resin are selected from the group consisting of phenolic resins, polyester resins, melamine-formaldehyde resins, urea-formaldehyde resins, casein-formaldehyde resins, polyimide resins, polyurethane resins, epoxy resins, diallyl phthalate resins, vinyl ester resins, polybutadiene(1,2) resins, cyanate ester resins, and cyanamide resins.
Claim 10
Dependent Claim
19 words
The improved fibrous material in accordance with claim 1 wherein said solid particles of thermosetting resin are polyimide resin.
Claim 11
Dependent Claim
46 words
The improved fibrous material in accordance with claim 9 wherein said solid particles of thermosetting resin are a reverse Diels-Alder polyimide resin which is substantially fully imidized and is capable of undergoing an addition crosslinking reaction in the substantial absence of the generation of volatile by-products.
Claim 12
Dependent Claim
18 words
The improved fibrous material in accordance with claim 9 wherein said particles of thermosetting resin are poly(bismaleimide) resin.
Claim 13
Dependent Claim
29 words
The improved fibrous material in accordance with claim 1 wherein said solid particles of thermosetting resin possess a particle size within the range of approximately 0.1 to 100 microns.
Claim 14
Dependent Claim
24 words
The improved fibrous material in accordance with claim 1 wherein said binding agent is polyacrylic acid having stiffened molecules possessing a cross-linked molecular structure.
Claim 15
Dependent Claim
30 words
The improved fibrous material in accordance with claim 1 wherein said binding agent is an ammonium or alkyl ammonium polyacrylate binding agent having stiffened molecules possessing a cross-linked molecular structure.
Claim 16
Dependent Claim
31 words
The improVed fibrous material in accordance with claim 1 wherein the concentration of aqueous medium within said fibrous material is within the range of approximately 10 to 70 percent by weight.
Claim 17
Dependent Claim
29 words
The improved fibrous material in accordance with claim 1 wherein said solid particles of thermosetting resin are present in a concentration of approximately 12 to 45 percent by weight.
Claim 18
Dependent Claim
89 words
The improved fibrous material in accordance with claim 1 wherein said plurality of adjoining substantially parallel reinforcing filaments (a) are present in a concentration of approximately 15 to 55 percent by weight, said polymeric water-soluble binding agent (b) is present in a concentration of approximately 0.02 to 2.2 percent by weight, said aqueous medium (c) is present in a concentration of approximately 10 to 70 percent by weight, and said solid particles of thermosetting resin (d) are present in a concentration of approximately 6 to 45 percent by weight.
Claim 19
Dependent Claim
31 words
The improved fibrous material in accordance with claim 1 wherein said drapable character is evidenced by a flexural rigidity of less than 15,000 mg.·cm. when tested in accordance with ASTM D1388.
Claim 20
Dependent Claim
19 words
The improved fibrous material in accordance with claim 1 which passes the tack test of NASA Technical Bulletin 1142.
Claim 21
Dependent Claim
49 words
The improved fibrous material in accordance with claim 1 which upon the application of heat and pressure can be transformed into a substantially void-free composite article which exhibits a zero degree flexural strength of at least 60 percent of the theoretical maximum when tested in accordance with ASTM D790.
Claim 22
Dependent Claim
49 words
The improved fibrous material in accordance with claim 1 which upon the application of heat and pressure can be transformed into a substantially void-free composite article which exhibits a zero degree flexural modulus of at least 80 percent of the theoretical value when tested in accordance with ASTM D790.
Claim 23
Dependent Claim
48 words
The improved fibrous material in accordance with claim 1 which upon the application of heat and pressure can be transformed into a substantially void-free composite article which exhibits a 90° tensile strength of at least 60 percent of the theoretical value when tested in accordance with ASTM D3039.
Claim 24
Dependent Claim
48 words
The improved fibrous material in accordance with claim 1 which upon the application of heat and pressure can be transformed into a substantially void-free composite article which exhibits a 90° tensile strength of at least 80 percent of the theoretical value when tested in accordance with ASTM D3039.
References Cited (Backward Citations)
CA588381A
Cited
GB178811A
Cited
US2596162A
Cited
US2609319A
Cited
FR1267996A
Cited
US3116192A
Cited
US3334071A
Cited
GB1264432A
Cited
US3779854A
Cited
GB1400852A
Cited
FR2223173A1
Cited
GB1424168A
Cited
US3970495A
Cited
GB1495845A
Cited
US4067845A
Cited
US4268473A
Cited
US4259379A
Cited
US4292105A
Cited
EP0013244A1
Cited
US4238542A
Cited
WO1983001755A1
Cited
US4626306A
Cited
EP0125472A2
Cited
US4680224A
Cited
US4680224B1
Cited
WO1986003449A1
Cited
US4721639A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-07-23 | 1994-01-22 | 1994-07-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-07-23 | 1998-01-22 | 1998-07-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-07-23 | 2002-01-22 | 2002-07-24 | $7700.00 | Window Closed / Lapsed |