EP0209360A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method for converting organosilicon polymers containing Si-H units to new and useful preceramic polymers and ceramic materials
Assignee: Massachusetts Institute of Technology
•
Filing: 1986-07-15
•
Granted: —
•
Expires: 2006-07-15
Abstract
Abstract A method of forming preceramic polymers using an organosilicon polymers containing Si-H repeat units by reacting it with alkali metal silylamids is disclosed. Preferably, the alkali metal silylamide is a polymeric alkali metal silylamide of the formula [(R 1 SiHNH) a (R 1 SiN) b (R 1 SiHNM) c ] m (where a+b+c=1; R 1 is a lower alkyl group having from 1 to about 6 carbon atoms, a substituted or unsubstituted alkenyl group having from 2 to about 6 carbon atoms, a substituted or unsubstituted lower aryl group having from 6 to about 10 carbon atoms, a tri(lower)alkyl- or di(lower)alkylsilyl group or a di-(lower)alkylamino group; M is an alkali metal or one-half equivalent of an alkaline earth metal; and n and m are integers greater than 1 ). The Si-H containing organosilicon polymer is preferably selected from the group consisting of organopolysilanes of the formula [(RSiH) x (RSi) y ] n (where R is a lower alkyl group having from 1 to about 6 carbon atoms, a lower alkenyl group having from 2 to about 6 carbon atoms, or a substituted or unsubstituted lower aryl group having from 6 to about 10 carbon atoms, and n is greater than 1), and polycarbosilanes having repeat units of the formula [R a Si(H)-(CH 2 ) q ] (where R S is H, a lower alkyl group having from 1 to about 6 carbon atoms, a cycloalkyl group having from 3 to about 6 carbon atoms, or a substituted or unsubstituted lower aryl group having from 6 to about 10 carbon atoms, q is an integer 1 or greater). Novel preceramic polymers formed by this method are also disclosed.
Inventors
- 👤 Dietmar Seyferth
- 👤 Yuan-Fu Yu
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 13:26
CPC Classifications
C; C08; C08G; C08G77/00; C08G77/60; C08L; C08L83/00; C08L83/16
Claims Analysis
Total Claims: 48
Claim 1
Independent Claim
69 words
A method for preparing preceramic organosilicon polymers, wherein the method comprises: (a) mixing an organosilicon polymer containing Si-H repeat units with at least a catalytic amount of an alkali metal amide or a silylamide in an organic solvent; (b) allowing the mixture of step (a) to react at room temperature or above ; and (c) quenching the reaction mixture with a reactive electrophile, thereby forming said preceramic organosilicon polymer.
Claim 2
Independent Claim
69 words
A method for preparing preceramic organosilicon polymers, wherein the method comprises: (a) mixing an organosilicon polymer containing Si-H repeat units with at least a catalytic amount of an alkali metal amide or a silylamide in an organic solvent; (b) allowing the mixture of step (a) to react at room temperature or above ; and (c) quenching the reaction mixture with a reactive electrophile, thereby forming said preceramic organosilicon polymer.
Claim 3
Dependent Claim
151 words
The method of claim 1 wherein the Si-H containing organosilicon polymer is selected from the group consisting of an organopolysilane of the formula [(RSiH) x (RSi) y ] n , where x + y - 1, R is a lower alkyl group having from 1 to about 6 carbon atoms, a lower alkenyl group having 2 to about 6 carbon atoms, a substituted or unsubstituted lower aryl group having from 6 to about 10 carbons atoms, and n is an integer greater than 1; and a polycarbosilane having a plurality of repeat units of the formula [R a Si(H)-(CH 2 )q] where R a is H, a lower alkyl group having from 1 to about 6 carbon atoms, a cycloalkyl group having 3 to about 6 carbon atoms, a substituted or unsubstituted lower aryl group having from 6 to about 10 carbon atoms, and q is an integer 1 or greater.
Claim 4
Dependent Claim
27 words
The method of claim 2 wherein the polycarbosilane contains at least about 25 mole % of repeat units of the formula [R a S i(H)-(CH 2 )ql.
Claim 5
Dependent Claim
15 words
The method of claim 2, wherein R and R a are a lower alkyl group.
Claim 6
Dependent Claim
14 words
The method of claim 2, wherein R and R a are CH 3 .
Claim 7
Dependent Claim
22 words
The method of claim 2, wherein the Si-H containing the organosilicon polymer is an organopolysilane and x = 1, y = 0.
Claim 8
Dependent Claim
115 words
The method of claim 2, wherein the alkali metal amide is a polymeric alkali metal silylamide of the formula [(R 1 SiHNH) a (R 1 SiN) b (R 1 SiHNM) c ] m , where a + b + c = 1, R is a lower alkyl group having from 1 to about 6 carbon atoms, a substituted or unsubstituted alkenyl group having from 2 to about 6 carbon toms, a substituted or unsubstituted lower aryl group having from 6 to about 10 carbon atoms, a tri(lower)alkyl- or di(lower)alkylsilyl group or a di(lower)alkylamino group; M is an alkali metal or one-half equivalent of an alkaline earth metal; and m is an integer greater than 1.
Claim 9
Dependent Claim
43 words
The method of claim 7 wherein the reaction mixture is quenched with an electrophile, E-X, where E is selected from the group consisting of lower alkyl groups and silyl groups and X is selected from the group consisting of halogen, sulfate and sulfonate.
Claim 10
Dependent Claim
61 words
The method of claim 7 wherein the Si-H containing organosilicon polymer is organopolysilane, and the polymeric metal silylamide is added in a sufficient quantity so that the excess carbon obtained on pyrolysis of the silylamide can react with excess silicon from the pyrolysis of the organopolysilane compound, thus producing a ceramic product which contains substantially no free silicon or free carbon.
Claim 11
Dependent Claim
12 words
The method of claim 7 wherein R is a lower alkyl group.
Claim 12
Dependent Claim
29 words
The method of claim 10 wherein the polymeric alkali metal silylamide has the formula [(CH 3 SiHNH) a (CH 3 SiN) b -(CH 3 SiHNK) c ] m .
Claim 13
Dependent Claim
14 words
The method of claim 10 wherein R and R a are CH 3 .
Claim 14
Dependent Claim
21 words
The method of claim 9 wherein the mixture is allowed to react by stirring at room temperature, then heating at reflux.
Claim 15
Dependent Claim
21 words
The method of claim 13 wherein the preceramic polymer is pyrolyzed under an inert gas stream to form a ceramic material.
Claim 16
Dependent Claim
10 words
The ceramic material formed by the method of claim 14.
Claim 17
Dependent Claim
23 words
The method of claim 9 wherein the mole ratio of organopolysilane to polymeric alkali metal silylamide ranges from about 4:1 to about 1:4.
Claim 18
Dependent Claim
10 words
A preceramic polymer formed by the method of claim 7.
Claim 19
Dependent Claim
15 words
The method of claim 2 wherein the alkali metal amide is an alkali metal silylamide.
Claim 20
Dependent Claim
117 words
The method of claim 18 wherein the alkali metal silylamide is [ R 2 R 3 R 4 Si] 2NM wherein R 2 , R 3 and R 4 are each a lower alkyl group having from 1 to about 6 carbon atoms, a lower alkoxy group having from 1 to about 6 carbon atoms, a substituted or unsubstituted vinyl group, a substituted or unsubstituted allyl group, a substituted or unsubstituted lower aryl group having from 6 to about 10 carbon atoms, a tri(lower)alkyl- or di(lower)alkylsilyl group or a di(lower)alkylamino group, R 2 , R and R may be the same or different; and M is an alkali metal or one-half equivalent of an alkaline earth metal.
Claim 21
Dependent Claim
35 words
The method of claim 19 wherein [R 2 R 3 R 4 Si] 2 NM is selected from [(CH 3 ) 2 (CH 2 =CH)Si] 2 NM and [(CH 3 ) 3 Si] 2 NM.
Claim 22
Dependent Claim
128 words
The method of claim 2 wherein the alkali metal silylamide is partially deprotonated cyclo-[R 5 R 6 SiNH] m containing [ R 5 R 6 S i NM] units wherein R 5 and R 6 are each a lower alkyl group having from 1 to about 6 carbon atoms, a lower alkoxy group having from 1 to about 6 carbon atoms, a substituted or unsubstituted vinyl group, a substituted or unsubstituted allyl group, a substituted or unsubstituted lower aryl group having from 6 to about 10 carbon atoms, a tri(lower)alkyl- or di(lower)alkylsilyl group or a di(lower)alkylamino group, R and R 6 may be the same or different; M is an alkali metal or one-half equivalent of an alkaline earth metal and m is an integer greater than 1.
Claim 23
Dependent Claim
29 words
The method of claim 21 wherein cyclo-[R 5 R 6 SiNH] m is selected from [(CH 3 ) 2 SiNH] m and [(CH 3 )(CH 2 =CH)SiN] m .
Claim 24
Dependent Claim
15 words
The method of claim 2 wherein the Si-H containing organosilicon polymer is a poly(phenyl)silicon polymer.
Claim 25
Dependent Claim
18 words
The method of claim 1 wherein the silylamide is a diorganocyclopolysilazane that is either partially or completely ring-opened.
Claim 26
Dependent Claim
94 words
The method of claim 24 where the dioranocyclopolysilazane comprises units having the formula [R 1 R 11 SiNH] m where R 1 is a lower alkyl group having from 1 to about 6 carbon atoms, a substituted or unsubstituted alkenyl group having from 2 to about 6 carbon atoms, a substituted or unsubstituted lower aryl group having from 6 to about 10 carbon atoms, a tri(lower)alkyl-or di(lower)alkylsilyl group or a di(lower)alkylamino group; R is defined as R l , and may be the same or different, and m is an integer greater than 1.
Claim 27
Dependent Claim
29 words
The method of claim 7 wherein the preceramic product is pyrolyzed in an inert atmosphere for a sufficient time and at a sufficient temperature to form a ceramic material.
Claim 28
Dependent Claim
25 words
The method of claim 2 wherein the Si-H containing organosilicon polymer is a polycarbosilane and the weight ratio of polycarbosilane:silylamide is about 10:1 or less.
Claim 29
Dependent Claim
60 words
The method of claim 7 wherein the Si-H containing organosilicon polymer is a mixture of the polycarbosilane and the organopolysilane, with a sufficient quantity of the organopolysilane added so that the excess silicon obtained on pyrolysis of the organopolysilane can react with excess carbon from the pyrolysis of the polycarbosilane and the silylamide, thereby reducing the amount of free carbon.
Claim 30
Dependent Claim
10 words
A preceramic polymer produced by the method of claim 28.
Claim 31
Independent Claim
166 words
A method for preparing a preceramic organosilicon polymer, wherein the method comprises: (a) generating a polysilylamide in the presence of an Si-H containing organosilicon polymer wherein the polysilylamide is generated by reacting the ammonolysis product of an R l SiHX 2 (where R is a lower alkyl group having from 1 to about 6 carbon atoms, a substituted or unsubstituted alkenyl group having from 2 to about 6 carbon atoms, a substituted or unsubstituted lower aryl group having from 6 to about 10 carbon atoms, a tri(lower)alkyl- or di(lower)alkylsilyl group or a di(lower)alkylamino group and X is a halogen), in the presence of a basic catalyst capable of deprotonating the hydrogen from a nitrogen atom adjacent to a silicon atom to generate the polysilylamide in situ; (b) allowing the in situ generated polysilylamide and the Si-H containing organosilicon polymer sufficient time to react with each other at room temperature; and (c) quenching the mixture with an organic halide or halosilane to produce the organosilicon preceramic polymer.
Claim 32
Independent Claim
166 words
A method for preparing a preceramic organosilicon polymer, wherein the method comprises: (a) generating a polysilylamide in the presence of an Si-H containing organosilicon polymer wherein the polysilylamide is generated by reacting the ammonolysis product of an R l SiHX 2 (where R is a lower alkyl group having from 1 to about 6 carbon atoms, a substituted or unsubstituted alkenyl group having from 2 to about 6 carbon atoms, a substituted or unsubstituted lower aryl group having from 6 to about 10 carbon atoms, a tri(lower)alkyl- or di(lower)alkylsilyl group or a di(lower)alkylamino group and X is a halogen), in the presence of a basic catalyst capable of deprotonating the hydrogen from a nitrogen atom adjacent to a silicon atom to generate the polysilylamide in situ; (b) allowing the in situ generated polysilylamide and the Si-H containing organosilicon polymer sufficient time to react with each other at room temperature; and (c) quenching the mixture with an organic halide or halosilane to produce the organosilicon preceramic polymer.
Claim 33
Dependent Claim
151 words
The method of claim 30 wherein the Si-H containing organosilicon polymer is selected from the group consisting of an organopolysilane of the formula [(RSiH) x (RSi) y ] n , where x + y - 1, R is a lower alkyl group having from 1 to about 6 carbon atoms, a lower alkenyl group having 2 to about 6 carbon atoms, a substituted or unsubstituted lower aryl group having from 6 to about 10 carbons atoms, and n is an integer greater than 1; and a polycarbosilane having a plurality of repeat units of the formula [R a Si(H)-(CH 2 )q] where R a is H, a lower alkyl group having from 1 to about 6 carbon atoms, a cycloalkyl group having 3 to about 6 carbon atoms, a substituted or unsubstituted lower aryl group having from 6 to about 10 carbon atoms, and q is an integer 1 or greater.
Claim 34
Dependent Claim
28 words
The method of claim 31 wherein the polycarbosilane contains at least about 25 mole % of repeat units of the formula [R a Si(H)-(CH 2 ) q ].
Claim 35
Dependent Claim
15 words
The method of claim 31, wherein R and R a are a lower alkyl group.
Claim 36
Dependent Claim
14 words
The method of claim 31, wherein R and R a are CH 3 .
Claim 37
Dependent Claim
21 words
The method of claim 31, wherein the Si-H containing organosilicon polymer is an organopolysilane and x - 1, y = 0.
Claim 38
Dependent Claim
59 words
The method of claim 31 wherein the Si-H containing organosilicon polymer is organopolysilane, and the organopolysilane is added in a sufficient quantity so that the excess carbon obtained on pyrolysis of the silylamide can react with excess silicon from the pyrolysis of the organopolysilane compound, thus producing a ceramic product which contains substantially no free silicon or free carbon.
Claim 39
Dependent Claim
21 words
The method of claim 31 wherein the mixture is allowed to react by stirring at room temperature, then heating at reflux.
Claim 40
Dependent Claim
30 words
The method of claim 31 wherein the preceramic polymer is pyrolyzed under an inert gas stream for a sufficient time and at a sufficient temperature to form a ceramic product.
Claim 41
Dependent Claim
10 words
The ceramic material formed by the method of claim 38.
Claim 42
Dependent Claim
23 words
The method of claim 31 wherein the mole ratio of organopolysilane to in situ generated silylamide ranges from about 4:1 to about 1:4.
Claim 43
Dependent Claim
63 words
The method of claim 31 wherein the Si-H containing organosilicon polymer is a mixture of the polycarbosilane and the organopolysilane, with a sufficient quantity of the organopolysilane added so that the excess silicon obtained on pyrolysis of the organopolysilane can react with excess carbon from the pyrolysis of the polycarbosilane and the in situ generated silylamide, thereby reducing the amount of free carbon.
Claim 44
Dependent Claim
10 words
A preceramic polymer formed by the method of claim 31.
Claim 45
Dependent Claim
141 words
A ceramic material formed by pyrolyzing a physical mixture of an Si-H containing organosilicon polymer and a polymer of the formula [(R 1 SiHNH) a (R 1 SiN) b (R 1 SiHNE) c ] m , where R is a lower alkyl group having from 1 to about 6 carbon atoms, a substituted or unsubstituted alkenyl group having from 2 to about 6 carbon atoms, a substituted or unsubstituted lower aryl group having from 6 to about 10 carbon atoms, a tri(lower) alkyl- or di(lower) alkylsilyl group or a di(lower) alkylamino group, n and m are integers greater than 1, and E is a moiety introduced by reaction of an electrophile, E-X, with [(R 1 SiNH) a (R 1 SiN) b (R 1 SiNM) c ] m where M is an alkali metal or one-half equivalent of an alkaline earth metal.
Claim 46
Dependent Claim
141 words
A ceramic material formed by pyrolyzing a physical mixture of an Si-H containing organosilicon polymer and a polymer of the formula [(R 1 SiHNH) a (R 1 SiN) b (R 1 SiHNE) c ] m , where R is a lower alkyl group having from 1 to about 6 carbon atoms, a substituted or unsubstituted alkenyl group having from 2 to about 6 carbon atoms, a substituted or unsubstituted lower aryl group having from 6 to about 10 carbon atoms, a tri(lower) alkyl- or di(lower) alkylsilyl group or a di(lower) alkylamino group, n and m are integers greater than 1, and E is a moiety introduced by reaction of an electrophile, E-X, with [(R 1 SiNH) a (R 1 SiN) b (R 1 SiNM) c ] m where M is an alkali metal or one-half equivalent of an alkaline earth metal.
Claim 47
Dependent Claim
24 words
The ceramic material of claim 43 wherein E is introduced by an electophile selected from the group consisting of lower alkyl halides and halosilanes.
Claim 48
Dependent Claim
151 words
The method of claim 51 wherein the Si-H containing organosilicon polymer is selected from the group consisting of an organopolysilane of the formula [(RSiH) x (RSi) y ] n , where x + y - 1, R is a lower alkyl group having from 1 to about 6 carbon atoms, a lower alkenyl group having 2 to about 6 carbon atoms, a substituted or unsubstituted lower aryl group having from 6 to about 10 carbons atoms, and n is an integer greater than 1; and a polycarbosilane having a plurality of repeat units of the formula [R a Si(H)-(CH 2 )q] where R a is H, a lower alkyl group having from 1 to about 6 carbon atoms, a cycloalkyl group having 3 to about 6 carbon atoms, a substituted or unsubstituted lower aryl group having from 6 to about 10 carbon atoms, and q is an integer 1 or greater.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.