Claims
- 1. A method of preparing fiber reinforced glass composites having a non-brittle failure mode when exposed to temperatures up to about 1300.degree. C. comprising:
- (a) reacting (1) a cyclosiloxane monomer having the formula ##STR3## where n is an integer from 3 to 30, R is hydrogen, and R' is an alkene of from 2 to 20 carbon atoms in which one vinyl carbon atom is directly bonded to silicon or (2) two or more different cyclosiloxane monomers having the formula of (1) where for at least one monomer R is hydrogen and R' is an alkyl group having from 1 to 20 carbon atoms and for the other monomers R is an alkene from 2 to 20 carbon atoms in which one vinyl carbon is directly bonded to silicon and R' is an alkyl group of from 1 to 20 carbon atoms, said reaction taking place in the presence of an effective amount of hydrosilylation catalyst;
- (b) applying the reaction product of (a) to at least one refractory fiber having a carbon coating about 0.01 .mu.m to 5 .mu.m thick and selected from the group consisting of boron, silicon carbide, graphite, silica, quartz, S-glass, E-glass, alumina, aluminosilicate, boron nitride, silicon nitride, boron carbide, titanium boride, titanium carbide, zirconium oxide, and zirconia-toughened alumina to form a prepreg;
- (c) laying-up plies of the prepreg of (b) to form a green structure;
- (d) curing the green structure of (c) at a temperature not greater than 250.degree. C.;
- (e) pyrolyzing the cured structure of (d) at a temperature of about 800.degree. C. to about 1400.degree. C. in non-oxidizing atmosphere;
- (f) recovering the pyrolyzed product of (e) as the fiber reinforced glass composite;
- (g) impregnating the pyrolyzed product of (f) with the reaction product of (a);
- (h) pyrolyzing the impregnated product of (g) at 800.degree. C.-1400.degree. C.;
- (i) repeating steps (g) and (h) until the composite is capable of non-brittle failure at temperatures up to about 1300.degree. C.
- 2. The method of claim 1 wherein steps (g) and (h) are repeated for 13 times.
CROSS-REFERENCE TO RELATED APPLICATIONS
This is a continuation-in-part of U.S. patent application Ser. No. 07/464,470, filed Jan. 12, 1990 still pending.
US Referenced Citations (6)
Foreign Referenced Citations (2)
Number |
Date |
Country |
4016569A1 |
Dec 1990 |
DEX |
4033493A1 |
May 1991 |
DEX |
Non-Patent Literature Citations (1)
Entry |
Prewo et al., Ceramic Bulletin, vol. 65, No. 2 (1986). |
Continuation in Parts (1)
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Number |
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Parent |
464470 |
Jan 1990 |
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