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US4460639A Expired / Lapsed US ⏱️ 0.0 years remaining

Fiber reinforced glass matrix composites

Assignee: Dow Silicones Corp
•
Filing: 1983-04-06
•
Granted: 1984-07-17
•
Expires: 2003-04-06
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Abstract

Abstract What is disclosed is a method of preparing fiber reinforced glass composites from high modulus fibers and resin sols of organosilsesquioxanes, metal oxides, and metal alkoxides. The composites are obtained by firing a partially cured, pressed, and post-cured prepreg to an elevated temperature in an inert atmosphere. A simple, low temperature laminating procedure is used in the preparation of these composites in place of the standard hot pressing technique.

Inventors

  • 👤 Frank K. Chi
  • 👤 Gary L. Stark

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 14:38
CPC Classifications
C; C03; C03C; C03C14/00; C03C14/002; C03C2214/00; C03C2214/02; Y; Y10; Y10S; Y10S428/00; Y10S428/902; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2918; Y10T428/2933; Y10T428/2962; Y10T428/30; Y10T428/31504; Y10T428/31652; Y10T428/31663; Y10T442/00; Y10T442/20; Y10T442/2926; Y10T442/2975; Y10T442/2984

Claims Analysis

Total Claims: 73
Claim 1
Independent Claim 438 words
A method of perparing fiber reinforced glass composites which method comprises (A) impregnating high modulus fibers with resin sol, which resin sol is selected from the group consisting essentially of (i) a sol of an organosilsesquioxane having the average formula [C.sub.6 H.sub.5 SiO.sub.3/2 ][RSiO.sub.3/2 ] wherein C 6 H 5 SiO 3/2 is present in said organosilsesquioxane in the amount of 5 to 100 percent by weight and RSiO 3/2 is present in the amount of 0 to 95 percent by weight based on the total weight of organosilsesquioxane present, and where R is an alkyl radical containing from 1 to 4 carbon atoms; (ii) a mixture of a sol of the organosilsesquioxane from (i) and a colloidal metal oxide, or a mixture of colloidal metal oxides, selected from the group consisting of SiO 2 , Al 2 O 3 , ZrO 2 , TiO 2 , SnO 2 , ZrSiO 4 , B 2 O 3 , La 2 O 3 , Sb 2 O 5 ; wherein C 6 H 5 SiO 3/2 is present in said organosilsesquioxane in the amount of 5 to 90 percent by weight and RSiO 3/2 is present in the amount of 10 to 95 percent by weight based on the total weight of organosilsesquioxane present; and (iii) a mixture of a sol of the organosilsesquioxane from (i) and a metal alkoxide, or a mixture of metal alkoxides, having the general formula M(OR').sub.x wherein M is a metal atom, R' is an alkyl radical containing from 1 to 4 carbon atoms, and x is 3 or 4, which metal alkoxide is capable of hydrolyzing and condensing in water; wherein C 6 H 5 SiO 3/2 is present in the amount of 5 to 90 percent by weight and RSiO 3/2 is present in the amount of 10 to 95 percent by weight based on the total weight of organosilsesquioxane present; (B) forming a prepreg by drying the product from (A); (C) heating the prepreg of (B) at an elevated temperature for a time sufficient to effect partial curing but to avoid excessive curing of the resin; (D) pressing the prepreg from (C) at a temperature not greater than about 300° C.; (E) curing the pressed prepreg from (D) at a temperature not greater than about 300° C. for a time sufficient to insure complete or nearly complete cross-linking in the prepreg; (F) slowly firing the pressed and cured prepreg from (E) to a temperature of at least 1000° C. in an inert atmosphere or vacuum until a fiber reinforced glass composite is obtained; and (G) cooling the fiber reinforced glass composite.
Claim 2
Independent Claim 438 words
A method of perparing fiber reinforced glass composites which method comprises (A) impregnating high modulus fibers with resin sol, which resin sol is selected from the group consisting essentially of (i) a sol of an organosilsesquioxane having the average formula [C.sub.6 H.sub.5 SiO.sub.3/2 ][RSiO.sub.3/2 ] wherein C 6 H 5 SiO 3/2 is present in said organosilsesquioxane in the amount of 5 to 100 percent by weight and RSiO 3/2 is present in the amount of 0 to 95 percent by weight based on the total weight of organosilsesquioxane present, and where R is an alkyl radical containing from 1 to 4 carbon atoms; (ii) a mixture of a sol of the organosilsesquioxane from (i) and a colloidal metal oxide, or a mixture of colloidal metal oxides, selected from the group consisting of SiO 2 , Al 2 O 3 , ZrO 2 , TiO 2 , SnO 2 , ZrSiO 4 , B 2 O 3 , La 2 O 3 , Sb 2 O 5 ; wherein C 6 H 5 SiO 3/2 is present in said organosilsesquioxane in the amount of 5 to 90 percent by weight and RSiO 3/2 is present in the amount of 10 to 95 percent by weight based on the total weight of organosilsesquioxane present; and (iii) a mixture of a sol of the organosilsesquioxane from (i) and a metal alkoxide, or a mixture of metal alkoxides, having the general formula M(OR').sub.x wherein M is a metal atom, R' is an alkyl radical containing from 1 to 4 carbon atoms, and x is 3 or 4, which metal alkoxide is capable of hydrolyzing and condensing in water; wherein C 6 H 5 SiO 3/2 is present in the amount of 5 to 90 percent by weight and RSiO 3/2 is present in the amount of 10 to 95 percent by weight based on the total weight of organosilsesquioxane present; (B) forming a prepreg by drying the product from (A); (C) heating the prepreg of (B) at an elevated temperature for a time sufficient to effect partial curing but to avoid excessive curing of the resin; (D) pressing the prepreg from (C) at a temperature not greater than about 300° C.; (E) curing the pressed prepreg from (D) at a temperature not greater than about 300° C. for a time sufficient to insure complete or nearly complete cross-linking in the prepreg; (F) slowly firing the pressed and cured prepreg from (E) to a temperature of at least 1000° C. in an inert atmosphere or vacuum until a fiber reinforced glass composite is obtained; and (G) cooling the fiber reinforced glass composite.
Claim 3
Dependent Claim 25 words
A method as described in claim 1 wherein said high modulus fibers are selected from the group consisting of carbon fibers and silicon carbide fibers.
Claim 4
Dependent Claim 15 words
A method as described in claim 2 wherein said fibers are essentially unidirectional and continuous.
Claim 5
Dependent Claim 14 words
A method as described in claim 3 wherein said fibers form a woven fabric.
Claim 6
Dependent Claim 66 words
A method as described in claim 2 wherein said resin sol is (i), wherein C 6 H 5 SiO 3/2 is present in said organosilsesquioxane in the amount of 30 to 70 percent by weight and RSiO 3/2 , is present in the amount of 30 to 70 percent by weight based on the total weight of organosilsesquioxane present, and where R is a methyl radical.
Claim 7
Dependent Claim 65 words
A method as described in claim 3 wherein said resin sol is (i), wherein C 6 H 5 SiO 3/2 is present in said organosilsesquioxane in the amount of 30 to 70 percent by weight and RSiO 3/2 is present in the amount of 30 to 70 percent by weight based on the total weight of organosilsesquioxane present, and where R is a methyl radical.
Claim 8
Dependent Claim 65 words
A method as described in claim 4 wherein said resin sol is (i), wherein C 6 H 5 SiO 3/2 is present in said organosilsesquioxane in the amount of 30 to 70 percent by weight and RSiO 3/2 is present in the amount of 30 to 70 percent by weight based on the total weight of organosilsesquioxane present, and where R is a methyl radical.
Claim 9
Dependent Claim 65 words
A method as described in claim 2 wherein said resin sol is (ii), wherein C 6 H 5 SiO 3/2 is present in said organosilsesquioxane in the amount of 30 to 70 percent by weight and RSiO 3/2 is present in the amount of 30 to 70 percent by weight based on the total weight of organosilsesquioxane present, and where R is a methyl radical.
Claim 10
Dependent Claim 65 words
A method as described in claim 3 wherein said resin sol is (ii), wherein C 6 H 5 SiO 3/2 is present in said organosilsesquioxane in the amount of 30 to 70 percent by weight and RSiO 3/2 is present in the amount of 30 to 70 percent by weight based on the total weight of organosilsesquioxane present, and where R is a methyl radical.
Claim 11
Dependent Claim 65 words
A method as described in claim 4 wherein said resin sol is (ii), wherein C 6 H 5 SiO 3/2 is present in said organosilsesquioxane in the amount of 30 to 70 percent by weight and RSiO 3/2 is present in the amount of 30 to 70 percent by weight based on the total weight of organosilsesquioxane present, and where R is a methyl radical.
Claim 12
Dependent Claim 51 words
A method as described in claim 2 wherein said resin sol is (ii) and wherein said colloidal metal oxide, or mixture of said colloidal metal oxides, is selected from the group consisting of SiO 2 , TiO 2 , Al 2 O 3 , ZrO 2 , and ZrSiO 4 .
Claim 13
Dependent Claim 44 words
A method as described in claim 8 wherein said colloidal metal oxide, or mixture of said colloidal metal oxides, is selected from the group consisting of SiO 2 , TiO 2 , Al 2 O 3 , ZrO 2 , and ZrSiO 4 .
Claim 14
Dependent Claim 44 words
A method as described in claim 9 wherein said colloidal metal oxide, or mixture of said colloidal metal oxides, is selected from the group consisting of SiO 2 , TiO 2 , Al 2 O 3 , ZrO 2 , and ZrSiO 4 .
Claim 15
Dependent Claim 44 words
A method as described in claim 10 wherein said colloidal metal oxide, or mixture of said colloidal metal oxides, is selected from the group consisting of SiO 2 , TiO 2 , Al 2 O 3 , ZrO 2 , and ZrSiO 4 .
Claim 16
Dependent Claim 16 words
A method as described in claim 13 wherein said colloidal metal oxide is SiO 2 .
Claim 17
Dependent Claim 16 words
A method as described in claim 14 wherein said colloidal metal oxide is SiO 2 .
Claim 18
Dependent Claim 18 words
A method as described in claim 13 wherein said colloidal metal oxide is Al 2 O 3 .
Claim 19
Dependent Claim 18 words
A method as described in claim 14 wherein said colloidal metal oxide is Al 2 O 3 .
Claim 20
Dependent Claim 16 words
A method as described in claim 13 wherein said colloidal metal oxide is ZrO 2 .
Claim 21
Dependent Claim 16 words
A method as described in claim 14 wherein said colloidal metal oxide is ZrO 2 .
Claim 22
Dependent Claim 65 words
A method as described in claim 2 wherein said resin sol is (iii), wherein C 6 H 5 SiO 3/2 is present in said organosilsesquioxane in the amount of 30 to 70 percent by weight and RSiO 3/2 is present in the amount of 30 to 70 percent by weight based on the total weight of organosilsesquioxane present, and where R is a methyl radical.
Claim 23
Dependent Claim 65 words
A method as described in claim 3 wherein said resin sol is (iii), wherein C 6 H 5 SiO 3/2 is present in said organosilsesquioxane in the amount of 30 to 70 percent by weight and RSiO 3/2 is present in the amount of 30 to 70 percent by weight based on the total weight of organosilsesquioxane present, and where R is a methyl radical.
Claim 24
Dependent Claim 65 words
A method as described in claim 4 wherein said resin sol is (iii), wherein C 6 H 5 SiO 3/2 is present in said organosilsesquioxane in the amount of 30 to 70 percent by weight and RSiO 3/2 is present in the amount of 30 to 70 percent by weight based on the total weight of organosilsesquioxane present, and where R is a methyl radical.
Claim 25
Dependent Claim 33 words
A method as described in claim 21 wherein M(OR') x is selected from the group consisting of Si(OR') 4 , Ti(OR') 4 , Al(OR') 3 , Zr(OR') 4 , and Sn(OR') 4 .
Claim 26
Dependent Claim 33 words
A method as described in claim 22 wherein M(OR') x is selected from the group consisting of Si(OR') 4 , Ti(OR') 4 , Al(OR') 3 , Zr(OR') 4 , and Sn(OR') 4 .
Claim 27
Dependent Claim 33 words
A method as described in claim 23 wherein M(OR') x is selected from the group consisting of Si(OR') 4 , Ti(OR') 4 , Al(OR') 3 , Zr(OR') 4 , and Sn(OR') 4 .
Claim 28
Dependent Claim 59 words
A method as described in claim 2 wherein the prepreg of step (B) is heated at a temperature of 50°-150° C. in step (C) for a time sufficient to effect partial curing but to avoid excessive curing of the resin; and wherein the prepreg from (C) is pressed in step (D) at a temperature of 100° to 300° C.
Claim 29
Dependent Claim 59 words
A method as described in claim 3 wherein the prepreg of step (B) is heated at a temperature of 50°-150° C. in step (C) for a time sufficient to effect partial curing but to avoid excessive curing of the resin; and wherein the prepreg from (C) is pressed in step (D) at a temperature of 100° to 300° C.
Claim 30
Dependent Claim 59 words
A method as described in claim 4 wherein the prepreg of step (B) is heated at a temperature of 50°-150° C. in step (C) for a time sufficient to effect partial curing but to avoid excessive curing of the resin; and wherein the prepreg from (C) is pressed in step (D) at a temperature of 100° to 300° C.
Claim 31
Dependent Claim 59 words
A method as described in claim 5 wherein the prepreg of step (B) is heated at a temperature of 50°-150° C. in step (C) for a time sufficient to effect partial curing but to avoid excessive curing of the resin; and wherein the prepreg from (C) is pressed in step (D) at a temperature of 100° to 300° C.
Claim 32
Dependent Claim 59 words
A method as described in claim 8 wherein the prepreg of step (B) is heated at a temperature of 50°-150° C. in step (C) for a time sufficient to effect partial curing but to avoid excessive curing of the resin; and wherein the prepreg from (C) is pressed in step (D) at a temperature of 100° to 300° C.
Claim 33
Dependent Claim 59 words
A method as described in claim 11 wherein the prepreg of step (B) is heated at a temperature of 50°-150° C. in step (C) for a time sufficient to effect partial curing but to avoid excessive curing of the resin; and wherein the prepreg from (C) is pressed in step (D) at a temperature of 100° to 300° C.
Claim 34
Dependent Claim 59 words
A method as described in claim 21 wherein the prepreg of step (B) is heated at a temperature of 50°-150° C. in step (C) for a time sufficient to effect partial curing but to avoid excessive curing of the resin; and wherein the prepreg from (C) is pressed in step (D) at a temperature of 100° to 300° C.
Claim 35
Dependent Claim 59 words
A method as described in claim 24 wherein the prepreg of step (B) is heated at a temperature of 50°-150° C. in step (C) for a time sufficient to effect partial curing but to avoid excessive curing of the resin; and wherein the prepreg from (C) is pressed in step (D) at a temperature of 100° to 300° C.
Claim 36
Dependent Claim 28 words
A method as described in claim 2 wherein said resin sol is (i) and wherein said organosilsesquioxane has the general formula C 6 H 5 SiO 3/2 .
Claim 37
Dependent Claim 85 words
A method as described in claim 2 wherein said resin sol is (i) and wherein said organosilsesquioxane has the general formula [C.sub.6 H.sub.5 SiO.sub.3/2 ][RSiO.sub.3/2 ] wherein C 6 H 5 SiO 3/2 is present in said organosilsesquioxane in the amount of 5 to 99 percent by weight and RSiO 3/2 is present in the amount of 1 to 95 percent by weight based on the total weight of organosilsesquioxane present, and where R is an alkyl radical containing from 1 to 4 carbon atoms.
Claim 38
Independent Claim 325 words
A method of preparing fiber reinforced glass composites which method comprises (A) impregnating high modulus fibers with a resin sol, which high modulus fibers are selected from the group consisting of carbon fibers and silicon carbide fibers and which resin sol is selected from the group consisting essentially of (i) a sol of an organosilsesquioxane having the average formula [C.sub.6 H.sub.5 SiO.sub.3/2 ][CH.sub.3 SiO.sub.3/2 ] wherein C 6 H 5 SiO 3/2 is present in said organosilsesquioxane in the amount of 30 to 60 percent by weight and CH 3 SiO 3/2 is present in the amount of 30 to 60 percent by weight based on the total weight of organosilsesquioxane present; (ii) a mixture of a sol of the organosilsesquioxane from (i) and a colloidal metal oxide, or a mixture of colloidal metal oxides, selected from the group consisting of SiO 2 , Al 2 O 3 , ZrO 2 , TiO 2 , and ZrSiO 4 ; (iii) a mixture of a sol of the organosilsesquioxane from (i) and a metal alkoxide, or mixture of metal alkoxides, selected from the group consisting of Si(OR') 4 , Ti(OR') 4 , Al(OR') 3 , Zr(OR') 4 , and Sn(OR') 4 ; (B) forming a prepreg by drying the product from (A); (C) heating the prepreg of (B) at a temperature of 50° to 150° C. for a time sufficient to effect partial curing but to avoid excessive curing of the resin; (D) pressing the prepreg from (C) at a temperature of 100° to 300° C.; (E) curing the pressed prepreg from (D) at a temperature not greater than about 300° C. for a time sufficient to insure complete or nearly complete cross-linking in the prepreg; (F) slowing firing the pressed and cured prepreg from (E) to a temperature of at least 1000° C. in an inert atmospheric or vacuum until a fiber reinforced glass composite is obtained; and (G) cooling the fiber reinforced glass composite.
Claim 39
Independent Claim 325 words
A method of preparing fiber reinforced glass composites which method comprises (A) impregnating high modulus fibers with a resin sol, which high modulus fibers are selected from the group consisting of carbon fibers and silicon carbide fibers and which resin sol is selected from the group consisting essentially of (i) a sol of an organosilsesquioxane having the average formula [C.sub.6 H.sub.5 SiO.sub.3/2 ][CH.sub.3 SiO.sub.3/2 ] wherein C 6 H 5 SiO 3/2 is present in said organosilsesquioxane in the amount of 30 to 60 percent by weight and CH 3 SiO 3/2 is present in the amount of 30 to 60 percent by weight based on the total weight of organosilsesquioxane present; (ii) a mixture of a sol of the organosilsesquioxane from (i) and a colloidal metal oxide, or a mixture of colloidal metal oxides, selected from the group consisting of SiO 2 , Al 2 O 3 , ZrO 2 , TiO 2 , and ZrSiO 4 ; (iii) a mixture of a sol of the organosilsesquioxane from (i) and a metal alkoxide, or mixture of metal alkoxides, selected from the group consisting of Si(OR') 4 , Ti(OR') 4 , Al(OR') 3 , Zr(OR') 4 , and Sn(OR') 4 ; (B) forming a prepreg by drying the product from (A); (C) heating the prepreg of (B) at a temperature of 50° to 150° C. for a time sufficient to effect partial curing but to avoid excessive curing of the resin; (D) pressing the prepreg from (C) at a temperature of 100° to 300° C.; (E) curing the pressed prepreg from (D) at a temperature not greater than about 300° C. for a time sufficient to insure complete or nearly complete cross-linking in the prepreg; (F) slowing firing the pressed and cured prepreg from (E) to a temperature of at least 1000° C. in an inert atmospheric or vacuum until a fiber reinforced glass composite is obtained; and (G) cooling the fiber reinforced glass composite.
Claim 40
Dependent Claim 34 words
A method as described in claim 37 wherein said resin sol is (i) and said resin sol contains from 30 to 50 percent by weight solids based on the total weight of the sol.
Claim 41
Dependent Claim 54 words
A method as described in claim 37 wherein said resin sols is (ii), said resin sol contains from 30 to 50 percent by weight solids based on the total weight of the sol, and the amount of metal oxides present is less than 50 percent by weight of the total solids in the sol.
Claim 42
Dependent Claim 56 words
A method as described in claim 37 wherein said resin sol is (iii), said resin sol contains from 30 to 50 percent by weight based on the total weight of the sol, and the amount of solids present from the metal alkoxides is less than 50 percent by weight of the total solids in the sol.
Claim 43
Dependent Claim 28 words
A method as described in claim 37 wherein the pressed and cured prepreg from (E) is slowly fired in Step (F) to a temperature of about 1200° C.
Claim 44
Dependent Claim 28 words
A method as described in claim 38 wherein the pressed and cured prepreg from (E) is slowly fired in Step (F) to a temperature of about 1200° C.
Claim 45
Dependent Claim 28 words
A method as described in claim 39 wherein the pressed and cured prepreg from (E) is slowly fired in Step (F) to a temperature of about 1200° C.
Claim 46
Dependent Claim 28 words
A method as described in claim 40 wherein the pressed and cured prepreg from (E) is slowly fired in Step (F) to a temperature of about 1200° C.
Claim 47
Dependent Claim 12 words
A fiber reinforced glass composite prepared by the method of claim 1.
Claim 48
Dependent Claim 12 words
A fiber reinforced glass composite prepared by the method of claim 2.
Claim 49
Dependent Claim 12 words
A fiber reinforced glass composite prepared by the method of claim 3.
Claim 50
Dependent Claim 12 words
A fiber reinforced glass composite prepared by the method of claim 4.
Claim 51
Dependent Claim 12 words
A fiber reinforced glass composite prepared by the method of claim 5.
Claim 52
Dependent Claim 12 words
A fiber reinforced glass composite prepared by the method of claim 8.
Claim 53
Dependent Claim 12 words
A fiber reinforced glass composite prepared by the method of claim 11.
Claim 54
Dependent Claim 12 words
A fiber reinforced glass composite prepared by the method of claim 21.
Claim 55
Dependent Claim 12 words
A fiber reinforced glass composite prepared by the method of claim 24.
Claim 56
Dependent Claim 12 words
A fiber reinforced glass composite prepared by the method of claim 37.
Claim 57
Dependent Claim 12 words
A fiber reinforced glass composite prepared by the method of claim 38.
Claim 58
Dependent Claim 12 words
A fiber reinforced glass composite prepared by the method of claim 39.
Claim 59
Dependent Claim 12 words
A fiber reinforced glass composite prepared by the method of claim 40.
Claim 60
Dependent Claim 30 words
A method as described in claim 2 wherein the fiber reinforced glass composite of step (G) is subjected to steps (A), (B), (E), (F), and (G) one or more times.
Claim 61
Dependent Claim 30 words
A method as described in claim 3 wherein the fiber reinforced glass composite of step (G) is subjected to steps (A), (B), (E), (F), and (G) one or more times.
Claim 62
Dependent Claim 30 words
A method as described in claim 4 wherein the fiber reinforced glass composite of step (G) is subjected to steps (A), (B), (E), (F), and (G) one or more times.
Claim 63
Dependent Claim 30 words
A method as described in claim 5 wherein the fiber reinforced glass composite of step (G) is subjected to steps (A), (B), (E), (F), and (G) one or more times.
Claim 64
Dependent Claim 30 words
A method as described in claim 8 wherein the fiber reinforced glass composite of step (G) is subjected to steps (A), (B), (E), (F), and (G) one or more times.
Claim 65
Dependent Claim 30 words
A method as described in claim 11 wherein the fiber reinforced glass composite of step (G) is subjected to steps (A), (B), (E), (F), and (G) one or more times.
Claim 66
Dependent Claim 30 words
A method as described in claim 38 wherein the fiber reinforced glass composite of step (G) is subjected to steps (A), (B), (E), (F), and (G) one or more times.
Claim 67
Dependent Claim 12 words
A fiber reinforced glass composite prepared by the method of claim 58.
Claim 68
Dependent Claim 12 words
A fiber reinforced glass composite prepared by the method of claim 59.
Claim 69
Dependent Claim 12 words
A fiber reinforced glass composite prepared by the method of claim 60.
Claim 70
Dependent Claim 12 words
A fiber reinforced glass composite prepared by the method of claim 61.
Claim 71
Dependent Claim 12 words
A fiber reinforced glass composite prepared by the method of claim 62.
Claim 72
Dependent Claim 12 words
A fiber reinforced glass composite prepared by the method of claim 63.
Claim 73
Dependent Claim 12 words
A fiber reinforced glass composite prepared by the method of claim 64.

References Cited (Backward Citations)

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