Hydridosiloxanes as precursors to ceramic products

Claim 3

The method of claim 1, wherein curing is conducted using a compound capable of coupling hydridosiloxanes.

Claim 4

The method of claim 1, wherein R' is hydrogen or lower alkyl.

Claim 5

The method of claim 1, wherein in step (c), the ceramic precursor is admixed with a metal powder selected from the group consisting of aluminum, barium, boron, calcium, copper, hafnium, iron, magnesium, molybdenum, niobium, silicon, titanium, tungsten, yttrium and zirconium.

Claim 6

The method of claim 4, wherein the metal powder has an average particle size in the range of approximately 0.01 to 100 μm.

Claim 7

The method of claim 1, wherein in step (c) said ceramic precursor is admixed with both a metal powder and a ceramic powder.

Claim 8

The method of claim 6, wherein said metal powder is comprised of particulate aluminum and said ceramic material is mullite.

Claim 9

The method of claim 1, wherein in step (c), the ceramic precursor is admixed with a metal powder selected from the group consisting of aluminum, barium, boron, calcium, copper, hafnium, iron, magnesium, molybdenum, niobium, silicon, titanium, tungsten, yttrium and zirconium.

Claim 10

The method of claim 3, wherein the metal powder has an average particle size in the range of approximately 0.01 to 100 μm.

Claim 11

The method of claim 3, wherein in step (c) said ceramic precursor is admixed with both a metal powder and a ceramic powder.

Claim 14

The method of claim 11, wherein in step (c), the ceramic precursor is admixed with a metal powder selected from the group consisting of aluminum, barium, boron, calcium, copper, hafnium, iron, magnesium, molybdenum, niobium, silicon, titanium, tungsten, yttrium and zirconium.

Claim 15

The method of claim 11, wherein in step (c) said ceramic precursor is admixed with both a metal powder and a ceramic powder.

Claim 18

The method of claim 14, wherein in step (c), the ceramic precursor is admixed with a metal powder selected from the group consisting of aluminum, barium, boron, calcium, copper, hafnium, iron, magnesium, molybdenum, niobium, silicon, titanium, tungsten, yttrium and zirconium.

Claim 19

The method of claim 15, wherein in step (c) said ceramic precursor is admixed with both a metal powder and a ceramic powder.

Claim 26

A ceramic coating prepared by the process comprising: (a) providing a hydridosiloxane starting material containing a plurality of Si--H bonds, and wherein at least about 20% of the silicon atoms in the starting material have a hydrogen atom bound thereto; (b) reacting said hydridosiloxane starting material with a hydroxyl-containing compound of the formula R'--OH, wherein R' is (i) hydrogen, (ii) C 1 -C 10 alkyl or aryl of 1-2 rings, optionally substituted with hydroxyl, lower alkyl, halogeno, silyl, or amino groups, or combinations thereof, (iii) silyl optionally containing additional hydroxyl groups, or (iv) a metal optionally bound to one or more ligands and/or containing additional hydroxyl groups, to give a ceramic precursor in which hydrogen atoms in the hydridosiloxane starting material have been replaced by oxygen-containing pendant groups OR' or oxygen-containing bridging moieties; (c) adding a metal powder, a ceramic powder, or both, either prior to, during, or after step (b), wherein a catalyst effective to activate Si--H bonds is added in step (b), step (c) or both, such that a preceramic mixture is provided; (d) curing the preceramic mixture at a temperature between approximately 20° C. and 250° C., to provide a cured preceramic mixture; and (e) pyrolyzing the preceramic mixture on a substrate, at a temperature of at least about 500° C., to provide a ceramic coating thereon.

Claim 27

A ceramic coating prepared by the process comprising: (a) providing a hydridosiloxane starting material containing a plurality of Si--H bonds, and wherein at least about 20% of the silicon atoms in the starting material have a hydrogen atom bound thereto; (b) reacting said hydridosiloxane starting material with a hydroxyl-containing compound of the formula R'--OH, wherein R' is (i) hydrogen, (ii) C 1 -C 10 alkyl or aryl of 1-2 rings, optionally substituted with hydroxyl, lower alkyl, halogeno, silyl, or amino groups, or combinations thereof, (iii) silyl optionally containing additional hydroxyl groups, or (iv) a metal optionally bound to one or more ligands and/or containing additional hydroxyl groups, to give a ceramic precursor in which hydrogen atoms in the hydridosiloxane starting material have been replaced by oxygen-containing pendant groups OR' or oxygen-containing bridging moieties; (c) adding a metal powder, a ceramic powder, or both, either prior to, during, or after step (b), wherein a catalyst effective to activate Si--H bonds is added in step (b), step (c) or both, such that a preceramic mixture is provided; (d) curing the preceramic mixture at a temperature between approximately 20° C. and 250° C., to provide a cured preceramic mixture; and (e) pyrolyzing the preceramic mixture on a substrate, at a temperature of at least about 500° C., to provide a ceramic coating thereon.

Claim 28

The ceramic coating composition of claim 21, wherein the substrate is coated with the preceramic mixture after step (c) and prior to step (d).

Claim 29

The ceramic coating composition of claim 21, wherein the substrate is coated with the cured preceramic mixture after step (d).

Claim 30

The ceramic coating composition of claim 21, wherein, in the hydroxyl-containing compound, R' is hydrogen or lower alkyl.

Claim 31

The ceramic coating composition of 21, wherein, in step (c), the ceramic precursor is admixed with a metal powder selected from the group consisting of aluminum, barium, boron, calcium, copper, hafnium, iron, magnesium, molybdenum, niobium, silicon, titanium, tungsten, yttrium and zirconium.

Claim 32

The ceramic coating composition of 21, wherein, in step (c), the ceramic precursor is admixed with a metal powder selected from the group consisting of aluminum, barium, boron, calcium, copper, hafnium, iron, magnesium, molybdenum, niobium, silicon, titanium, tungsten, yttrium and zirconium.

Claim 33

A ceramic coating prepared by the process comprising: (a) providing a hydridosiloxane starting material containing a plurality of Si--H bonds, and wherein at least about 20% of the silicon atoms present in the starting material have a hydrogen atom bound thereto; (b) introducing carbon-containing moieties into said hydridosiloxane starting material by reaction with a compound containing an unsaturated carbon-carbon bond, to give a ceramic precursor in which hydrogen atoms in the hydridosiloxane starting material have been replaced by pendant or bridging carbon-containing moieties; (c) adding a metal powder, a ceramic powder, or both, either prior to, during, or after step (b), wherein a catalyst effective to activate Si--H bonds and unsaturated carbon-carbon bonds is added in step (b), step (c) or both, such that a preceramic mixture is provided; (d) curing the preceramic mixture at a temperature between approximately 20° C. and 250° C., to provide a cured preceramic mixture; and (e) pyrolyzing the preceramic mixture on a substrate, at a temperature of at least about 500° C., to provide a ceramic coating thereon.

Claim 34

A ceramic coating prepared by the process comprising: (a) providing a hydridosiloxane starting material containing a plurality of Si--H bonds, and wherein at least about 20% of the silicon atoms present in the starting material have a hydrogen atom bound thereto; (b) introducing carbon-containing moieties into said hydridosiloxane starting material by reaction with a compound containing an unsaturated carbon-carbon bond, to give a ceramic precursor in which hydrogen atoms in the hydridosiloxane starting material have been replaced by pendant or bridging carbon-containing moieties; (c) adding a metal powder, a ceramic powder, or both, either prior to, during, or after step (b), wherein a catalyst effective to activate Si--H bonds and unsaturated carbon-carbon bonds is added in step (b), step (c) or both, such that a preceramic mixture is provided; (d) curing the preceramic mixture at a temperature between approximately 20° C. and 250° C., to provide a cured preceramic mixture; and (e) pyrolyzing the preceramic mixture on a substrate, at a temperature of at least about 500° C., to provide a ceramic coating thereon.

Claim 35

The ceramic coating composition of claim 26, wherein the substrate is coated with the preceramic mixture after step (c) and prior to step (d).

Claim 36

The ceramic coating composition of claim 26, wherein the substrate is coated with the cured preceramic mixture after step (d).

Claim 37

The ceramic coating composition of 26, wherein, in step (c), the ceramic precursor is admixed with a metal powder selected from the group consisting of aluminum, barium, boron, calcium, copper, hafnium, iron, magnesium, molybdenum, niobium, silicon, titanium, tungsten, yttrium and zirconium.

Claim 38

The ceramic coating composition of 26, wherein, in step (c), the ceramic precursor is admixed with a metal powder selected from the group consisting of aluminum, barium, boron, calcium, copper, hafnium, iron, magnesium, molybdenum, niobium, silicon, titanium, tungsten, yttrium and zirconium.

Claim 39

A ceramic coating prepared by the process comprising: (a) providing a hydridosiloxane starting material containing a plurality of Si--H bonds, and wherein at least about 20% of the silicon atoms present in the starting material have a hydrogen atom bound thereto; (b) introducing nitrogen-containing moieties into said starting material by reaction with a compound HNR" 2 wherein the R" are independently selected from hydrogen, lower alkyl, silyl, and aryl of 1-2 rings, to give a ceramic precursor in which hydrogen atoms in the hydridosiloxane polymer have been replaced with nitrogen-containing pendant or crosslinking groups; (c) adding a metal powder, a ceramic powder, or both, either prior to, during, or after step (b), wherein a catalyst effective to activate Si--H bonds is added in step (b), step (c) or both, such that a preceramic mixture is provided; (d) curing the preceramic mixture at a temperature between approximately 20° C. and 250° C., to provide a cured preceramic mixture; and (e) pyrolyzing the preceramic mixture on a substrate, at a temperature of at least about 500° C., to provide a ceramic coating thereon.

Claim 40

A ceramic coating prepared by the process comprising: (a) providing a hydridosiloxane starting material containing a plurality of Si--H bonds, and wherein at least about 20% of the silicon atoms present in the starting material have a hydrogen atom bound thereto; (b) introducing nitrogen-containing moieties into said starting material by reaction with a compound HNR" 2 wherein the R" are independently selected from hydrogen, lower alkyl, silyl, and aryl of 1-2 rings, to give a ceramic precursor in which hydrogen atoms in the hydridosiloxane polymer have been replaced with nitrogen-containing pendant or crosslinking groups; (c) adding a metal powder, a ceramic powder, or both, either prior to, during, or after step (b), wherein a catalyst effective to activate Si--H bonds is added in step (b), step (c) or both, such that a preceramic mixture is provided; (d) curing the preceramic mixture at a temperature between approximately 20° C. and 250° C., to provide a cured preceramic mixture; and (e) pyrolyzing the preceramic mixture on a substrate, at a temperature of at least about 500° C., to provide a ceramic coating thereon.

Claim 41

The ceramic coating composition of claim 30, wherein the substrate is coated with the preceramic mixture after step (c) and prior to step (d).

Claim 42

The ceramic coating composition of claim 30, wherein the substrate is coated with the cured preceramic mixture after step (d).

Claim 43

The ceramic coating composition of claim 30, wherein, in the compound HNR" 2 , the R" moieties are independently selected from the group consisting of hydrogen and lower alkyl.

Claim 44

The ceramic coating composition of claim 30, wherein, in step (c), the ceramic precursor is admixed with a metal powder selected from the group consisting of aluminum, barium, boron, calcium, copper, hafnium, iron, magnesium, molybdenum, niobium, silicon, titanium, tungsten, yttrium and zirconium.

Claim 45

A ceramic coating prepared by the process comprising: (a) providing a hydridosiloxane starting material containing a plurality of Si--H bonds, and wherein at least about 20% of the silicon atoms present in the starting material have a hydrogen atom bound thereto; (b) reacting said hydridosiloxane starting material with a compound selected from the group consisting of ML a and L a M-OH, wherein M is a metal atom, L is an organic or inorganic ligand associated therewith, and a represents the molar ratio L/M, to give a ceramic precursor in which Said activated Si--H bonds have been replaced by Si--M bonds; (c) adding a metal powder, a ceramic powder, or both, either prior to, during, or after step (b), wherein a catalyst effective to activate Si--H bonds is added in step (b), step (c) or both, such that a preceramic mixture is provided; (d) curing the preceramic mixture at a temperature between approximately 20° C. and 250° C., to provide a cured preceramic mixture; and (e) pyrolyzing the preceramic mixture on a substrate, at a temperature of at least about 500° C., to provide a ceramic coating thereon.

Claim 46

A ceramic coating prepared by the process comprising: (a) providing a hydridosiloxane starting material containing a plurality of Si--H bonds, and wherein at least about 20% of the silicon atoms present in the starting material have a hydrogen atom bound thereto; (b) reacting said hydridosiloxane starting material with a compound selected from the group consisting of ML a and L a M-OH, wherein M is a metal atom, L is an organic or inorganic ligand associated therewith, and a represents the molar ratio L/M, to give a ceramic precursor in which Said activated Si--H bonds have been replaced by Si--M bonds; (c) adding a metal powder, a ceramic powder, or both, either prior to, during, or after step (b), wherein a catalyst effective to activate Si--H bonds is added in step (b), step (c) or both, such that a preceramic mixture is provided; (d) curing the preceramic mixture at a temperature between approximately 20° C. and 250° C., to provide a cured preceramic mixture; and (e) pyrolyzing the preceramic mixture on a substrate, at a temperature of at least about 500° C., to provide a ceramic coating thereon.

Claim 47

The ceramic coating composition of claim 35, wherein the substrate is coated with the proceramic mixture after step (c) and prior to step (d).

Claim 48

The ceramic coating composition of claim 35, wherein the substrate is coated with the cured proceramic mixture after step (d).

Claim 49

The ceramic coating composition of claim 35, wherein, in step (c), the ceramic precursor is admixed with a metal powder selected from the group consisting of aluminum, barium, boron, calcium, copper, hafnium, iron, magnesium, molybdenum, niobium, silicon, titanium, tungsten, yttrium and zirconium.

Claim 50

A ceramic coating composition prepared by the process comprising: (a) providing a starting material comprising a silicon-containing polymer having a plurality of Si--H groups; (b) curing said silicon-containing polymer with light, by dehydrocoupling or by reaction with a coupling agent, to provide a ceramic precursor; (c) admixing (i) a catalyst effective to activate Si--H bonds, and (ii) a metal powder, with either the silicon-containing polymer, the ceramic precursor, or both, to provide a preceramic mixture; (d) coating a substrate with the preceramic mixture, whereby a preceramic coating is provided; and (e) pyrolyzing the preceramic ceramic coating on the substrate, to provide a ceramic coating thereon.

Claim 51

A ceramic coating composition prepared by the process comprising: (a) providing a starting material comprising a silicon-containing polymer having a plurality of Si--H groups; (b) curing said silicon-containing polymer with light, by dehydrocoupling or by reaction with a coupling agent, to provide a ceramic precursor; (c) admixing (i) a catalyst effective to activate Si--H bonds, and (ii) a metal powder, with either the silicon-containing polymer, the ceramic precursor, or both, to provide a preceramic mixture; (d) coating a substrate with the preceramic mixture, whereby a preceramic coating is provided; and (e) pyrolyzing the preceramic ceramic coating on the substrate, to provide a ceramic coating thereon.

Claim 52

A fiber-reinforced ceramic matrix composite prepared by the process comprising: (a) providing a hydridosiloxane starting material containing a plurality of Si--H bonds, and wherein at least about 20% of the silicon atoms in the starting material have a hydrogen atom bound thereto; (b) reacting said hydridosiloxane starting material with a hydroxyl-containing compound of the formula R'--OH, wherein R' is (i) hydrogen, (ii) C 1 -C 10 alkyl or aryl of 1-2 rings, optionally substituted with hydroxyl, lower alkyl, halogeno, silyl, or amino groups, or combinations thereof, (iii) silyl optionally containing additional hydroxyl groups, or (iv) a metal optionally bound to one or more ligands and/or containing additional hydroxyl groups, to give a ceramic precursor in which hydrogen atoms in the hydridosiloxane starting material have been replaced by oxygen-containing pendant groups OR' or oxygen-containing bridging moieties; (c) adding a metal powder, a ceramic powder, or both, either prior to, during, or after step (b), wherein a catalyst effective to activate Si--H bonds is added in step (b), step (c) or both, such that a preceramic mixture is provided; (d) curing the preceramic mixture at a temperature between approximately 20° C. and 250° C., to provide a cured preceramic mixture; (e) incorporating ceramic fibers into the preceramic mixture, either prior to or during step (d), to provide a fiber-containing preceramic mixture; and (f) pyrolyzing the fiber-containing preceramic mixture, at a temperature of at least about 500° C., to provide a fiber-reinforced ceramic matrix composite.

Claim 53

A fiber-reinforced ceramic matrix composite prepared by the process comprising: (a) providing a hydridosiloxane starting material containing a plurality of Si--H bonds, and wherein at least about 20% of the silicon atoms in the starting material have a hydrogen atom bound thereto; (b) reacting said hydridosiloxane starting material with a hydroxyl-containing compound of the formula R'--OH, wherein R' is (i) hydrogen, (ii) C 1 -C 10 alkyl or aryl of 1-2 rings, optionally substituted with hydroxyl, lower alkyl, halogeno, silyl, or amino groups, or combinations thereof, (iii) silyl optionally containing additional hydroxyl groups, or (iv) a metal optionally bound to one or more ligands and/or containing additional hydroxyl groups, to give a ceramic precursor in which hydrogen atoms in the hydridosiloxane starting material have been replaced by oxygen-containing pendant groups OR' or oxygen-containing bridging moieties; (c) adding a metal powder, a ceramic powder, or both, either prior to, during, or after step (b), wherein a catalyst effective to activate Si--H bonds is added in step (b), step (c) or both, such that a preceramic mixture is provided; (d) curing the preceramic mixture at a temperature between approximately 20° C. and 250° C., to provide a cured preceramic mixture; (e) incorporating ceramic fibers into the preceramic mixture, either prior to or during step (d), to provide a fiber-containing preceramic mixture; and (f) pyrolyzing the fiber-containing preceramic mixture, at a temperature of at least about 500° C., to provide a fiber-reinforced ceramic matrix composite.

Claim 54

The ceramic matrix of claim 40, wherein the ceramic fibers are incorporated into the preceramic mixture prior to step (d).

Claim 55

The ceramic matrix composite of claim 40, wherein, in the hydroxyl-containing compound, R' is hydrogen or lower alkyl.

Claim 56

The ceramic matrix composite of claim 40, wherein, in step (c), the ceramic precursor is admixed with a metal powder selected from the group consisting of aluminum, barium, boron, calcium, copper, hafnium, iron, magnesium, molybdenum, niobium, silicon, titanium, tungsten, yttrium and zirconium.

Claim 57

A fiber-reinforced ceramic matrix composite prepared by the process comprising: (a) providing a hydridosiloxane starting material containing a plurality of Si--H bonds, and wherein at least about 20% of the silicon atoms present in the starting material have a hydrogen atom bound thereto; (b) introducing carbon-containing moieties into said hydridosiloxane starting material by reaction with a compound containing an unsaturated carbon-carbon bond, to give a ceramic precursor in which hydrogen atoms in the hydridosiloxane starting material have been replaced by pendant or bridging carbon-containing moieties; (c) adding a metal powder, a ceramic powder, or both, either prior to, during, or after step (b), wherein a catalyst effective to activate Si--H bonds and unsaturated carbon-carbon bonds is added in step (b), step (c) or both, such that a preceramic mixture is provided; (d) curing the preceramic mixture at a temperature between approximately 20° C. and 250° C., to provide a cured preceramic mixture; (e) incorporating ceramic fibers into the preceramic mixture, either prior to or during step (d), to provide a fiber-containing preceramic mixture; and (f) pyrolyzing the fiber-containing preceramic mixture, at a temperature of at least about 500° C., to provide a fiber-reinforced ceramic matrix composite.

Claim 58

A fiber-reinforced ceramic matrix composite prepared by the process comprising: (a) providing a hydridosiloxane starting material containing a plurality of Si--H bonds, and wherein at least about 20% of the silicon atoms present in the starting material have a hydrogen atom bound thereto; (b) introducing carbon-containing moieties into said hydridosiloxane starting material by reaction with a compound containing an unsaturated carbon-carbon bond, to give a ceramic precursor in which hydrogen atoms in the hydridosiloxane starting material have been replaced by pendant or bridging carbon-containing moieties; (c) adding a metal powder, a ceramic powder, or both, either prior to, during, or after step (b), wherein a catalyst effective to activate Si--H bonds and unsaturated carbon-carbon bonds is added in step (b), step (c) or both, such that a preceramic mixture is provided; (d) curing the preceramic mixture at a temperature between approximately 20° C. and 250° C., to provide a cured preceramic mixture; (e) incorporating ceramic fibers into the preceramic mixture, either prior to or during step (d), to provide a fiber-containing preceramic mixture; and (f) pyrolyzing the fiber-containing preceramic mixture, at a temperature of at least about 500° C., to provide a fiber-reinforced ceramic matrix composite.

Claim 59

The ceramic matrix composite of claim 44, wherein the ceramic fibers are incorporated into the preceramic mixture prior to step (d).

Claim 60

The ceramic matrix composite of claim 44, wherein, in step (c), the ceramic precursor is admixed with a metal powder selected from the group consisting of aluminum, barium, boron, calcium, copper, hafnium, iron, magnesium, molybdenum, niobium, silicon, titanium, tungsten, yttrium and zirconium.

Claim 61

A ceramic matrix composite prepared by the process comprising: (a) providing a hydridosiloxane starting material containing a plurality of Si--H bonds, and wherein at least about 20% of the silicon atoms present in the starting material have a hydrogen atom bound thereto; (b) introducing nitrogen-containing moieties into said starting material by reaction with a compound HNR" 2 wherein the R" are independently selected from hydrogen, lower alkyl, silyl, and aryl of 1-2 rings, to give a ceramic precursor in which hydrogen atoms in the hydridosiloxane polymer have been replaced with nitrogen-containing pendant or crosslinking groups; (c) adding a metal powder, a ceramic powder, or both, either prior to, during, or after step (b), wherein a catalyst effective to activate Si--H bonds is added in step (b), step (c) or both, such that a preceramic mixture is provided; (d) curing the preceramic mixture at a temperature between approximately 20° C. and 250° C., to provide a cured preceramic mixture; (e) incorporating ceramic fibers into the preceramic mixture, either prior to or during step (d), to provide a fiber-containing preceramic mixture; and (f) pyrolyzing the fiber-containing preceramic mixture, at a temperature of at least about 500° C., to provide a fiber-reinforced ceramic matrix composite.

Claim 62

A ceramic matrix composite prepared by the process comprising: (a) providing a hydridosiloxane starting material containing a plurality of Si--H bonds, and wherein at least about 20% of the silicon atoms present in the starting material have a hydrogen atom bound thereto; (b) introducing nitrogen-containing moieties into said starting material by reaction with a compound HNR" 2 wherein the R" are independently selected from hydrogen, lower alkyl, silyl, and aryl of 1-2 rings, to give a ceramic precursor in which hydrogen atoms in the hydridosiloxane polymer have been replaced with nitrogen-containing pendant or crosslinking groups; (c) adding a metal powder, a ceramic powder, or both, either prior to, during, or after step (b), wherein a catalyst effective to activate Si--H bonds is added in step (b), step (c) or both, such that a preceramic mixture is provided; (d) curing the preceramic mixture at a temperature between approximately 20° C. and 250° C., to provide a cured preceramic mixture; (e) incorporating ceramic fibers into the preceramic mixture, either prior to or during step (d), to provide a fiber-containing preceramic mixture; and (f) pyrolyzing the fiber-containing preceramic mixture, at a temperature of at least about 500° C., to provide a fiber-reinforced ceramic matrix composite.

Claim 63

The ceramic matrix of claim 47, wherein the ceramic fibers are incorporated into the preceramic mixture prior to step (d).

Claim 64

The ceramic matrix composite of claim 47, wherein, in the compound HNR" 2 , the R" moieties are independently selected from the group consisting of hydrogen and lower alkyl.

Claim 65

The ceramic matrix composite of claim 47, wherein, in step (c), the ceramic precursor is admixed with a metal powder selected from the group consisting of aluminum, barium, boron, calcium, copper, hafnium, iron, magnesium, molybdenum, niobium, silicon, titanium, tungsten, yttrium and zirconium.

Claim 66

A fiber-reinforced ceramic matrix composite prepared by the process comprising: (a) providing a hydridosiloxane starting material containing a plurality of Si--H bonds, and wherein at least about 20% of the silicon atoms present in the starting material have a hydrogen atom bound thereto; (b) reacting said hydridosiloxane starting material with a compound selected from the group consisting of ML a and L a M-OH, wherein M is a metal atom, L is an organic or inorganic ligand associated therewith, and a represents the molar ratio L/M, to give a ceramic precursor in which said activated Si--H bonds have been replaced by Si--M bonds; (c) adding a metal powder, a ceramic powder, or both, either prior to, during, or after step (b), wherein a catalyst effective to activate Si--H bonds is added in step (b), step (c) or both, such that a preceramic mixture is provided; (d) curing the preceramic mixture at a temperature between approximately 20° C. and 250° C., to provide a cured preceramic mixture; (e) incorporating ceramic fibers into the preceramic mixture, either prior to or during step (d), to provide a fiber-containing preceramic mixture; and (f) pyrolyzing the fiber-containing preceramic mixture, at a temperature of at least about 500° C., to provide a fiber-reinforced ceramic matrix composite.

Claim 67

A fiber-reinforced ceramic matrix composite prepared by the process comprising: (a) providing a hydridosiloxane starting material containing a plurality of Si--H bonds, and wherein at least about 20% of the silicon atoms present in the starting material have a hydrogen atom bound thereto; (b) reacting said hydridosiloxane starting material with a compound selected from the group consisting of ML a and L a M-OH, wherein M is a metal atom, L is an organic or inorganic ligand associated therewith, and a represents the molar ratio L/M, to give a ceramic precursor in which said activated Si--H bonds have been replaced by Si--M bonds; (c) adding a metal powder, a ceramic powder, or both, either prior to, during, or after step (b), wherein a catalyst effective to activate Si--H bonds is added in step (b), step (c) or both, such that a preceramic mixture is provided; (d) curing the preceramic mixture at a temperature between approximately 20° C. and 250° C., to provide a cured preceramic mixture; (e) incorporating ceramic fibers into the preceramic mixture, either prior to or during step (d), to provide a fiber-containing preceramic mixture; and (f) pyrolyzing the fiber-containing preceramic mixture, at a temperature of at least about 500° C., to provide a fiber-reinforced ceramic matrix composite.

Claim 68

The ceramic matrix composite of claim 51, wherein the ceramic fibers are incorporated into the preceramic mixture prior to step (d).

Claim 69

The ceramic matrix composite of claim 51, wherein, in step (c), the ceramic precursor is admixed with a metal powder selected from the group consisting of aluminum, barium, boron, calcium, copper, hafnium, iron, magnesium, molybdenum, niobium, silicon, titanium, tungsten, yttrium and zirconium.

Claim 70

A fiber-reinforced ceramic matrix composite prepared by the process comprising: (a) providing a starting material comprising a silicon-containing polymer having a plurality of Si--H groups; (b) curing said silicon-containing polymer with light, by dehydrocoupling or by reaction with a coupling agent, to provide a ceramic precursor; (c) admixing (i) a catalyst effective to activate Si--H bonds, and (ii) a metal powder, with either the silicon-containing polymer, the ceramic precursor, or both, to provide a preceramic mixture; (d) incorporating ceramic fibers into the preceramic mixture to provide a fiber-containing preceramic mixture; and (e) pyrolyzing the fiber-containing preceramic mixture, at a temperature of at least about 500° C., to provide a fiber-reinforced ceramic matrix composite.

Claim 71

A fiber-reinforced ceramic matrix composite prepared by the process comprising: (a) providing a starting material comprising a silicon-containing polymer having a plurality of Si--H groups; (b) curing said silicon-containing polymer with light, by dehydrocoupling or by reaction with a coupling agent, to provide a ceramic precursor; (c) admixing (i) a catalyst effective to activate Si--H bonds, and (ii) a metal powder, with either the silicon-containing polymer, the ceramic precursor, or both, to provide a preceramic mixture; (d) incorporating ceramic fibers into the preceramic mixture to provide a fiber-containing preceramic mixture; and (e) pyrolyzing the fiber-containing preceramic mixture, at a temperature of at least about 500° C., to provide a fiber-reinforced ceramic matrix composite.

Claim 72

The method of claim 13, wherein, in the compound HNR" a , the R" moieties are independently selected from the group consisting of hydrogen and lower alkyl.