Organic compounds -- part of the class 532-570 series – Organic compounds – Silicon containing
Reexamination Certificate
2000-09-25
2001-09-04
Shaver, Paul F. (Department: 1621)
Organic compounds -- part of the class 532-570 series
Organic compounds
Silicon containing
C528S014000, C528S021000
Reexamination Certificate
active
06284908
ABSTRACT:
BACKGROUND OF THE INVENTION
The present application is generally directed to a method of making polysilsesquioxane and organohydridosilane compounds and, more particularly, to a base-catalyzed, disproportionation method of making polysilsesquioxane and organohydridosilane compounds.
Organopolysilsesquioxanes have applications as material for low-K dielectrics, ceramic precursors and photoresists. Organohydridosilane compounds have applications in the electronic and semiconductor fields to coat silicon chips and other components, serving as protective coatings and interlevel dielectric layers.
Polysilsesquioxane compounds can be produced by hydrolytic condensation of a silane in an aqueous solution of ammonia or an amine. However, organohydridosilanes are not produced (Kimura, U.S. Pat. No. 4,528,390).
Polysilsesquioxanes can also be made using a sol-gel synthesis method involving the hydrolysis of some organotricholorosilanes or organotrialkoxysilanes in the presence of acid or base catalysts and organic solvents. However, under sol-gel conditions most organotrialkoxysilanes do not afford silsesquioxane gels. This limits the range of organic functionalities that can be introduced into these hybrid organic-inorganic materials. This polymerization process also requires solvent and stoichiometric water and produces alcohol and water condensation by-products.
In an alternative route to polysilisesquioxanes, catalytic disproportionation, by titanium complexes, of linear or cyclic oligomers of methylhydridosiloxanes have produced polymethylsilsesquioxanes (R. Laine, J. Rahn, K. Youngdahl, F. Babonneau, M. Hoppe, Z. Zhang, and J. Harrod, Chem. Mater., 1990, 2, 464-472). This process requires inert conditions because of the moisture and air sensitivity of the titanium catalyst. Redistristribution reactions of alkoxy-and siloxysilanes have also been demonstrated using dimethyltitanocene catalysts (S. Xin, C. Aitken, J. Harrod, Y. Mu, and E. Samuel, Can. J. Chem, 1990, 68, 471-476).
Hydridosiloxanes and organohydridosiloxanes can be produced by catalyzing the hydrolysis and condensation of a silane monomer, where the silane monomer is contacted with a phase transfer catalyst in the presence of a reaction mixture comprising a nonpolar or polar solvent (Hacker et al., U.S. Pat. No. 6,043,330).
REFERENCES:
patent: 4417067 (1983-11-01), Kotzsch et al.
patent: 4528390 (1985-07-01), Kimura
patent: 5504235 (1996-04-01), Hirose et al.
patent: 5892087 (1999-04-01), Yung et al.
patent: 6043330 (2000-03-01), Hacker et al.
Laine, R., Rahn, J. Youngdahl, K., Babonneau, F., Hoppe, M., Zhang, Z., and Harrod, J., “Synthesis and high-temperature chemistry of methylsilsesquioxane polymers produced by titanium-catalyzed redistribution of methylhydridooligo-and -polysiloxanes,” Chem. Mater., 1990, 2, 464-472.
Xin, S., Aitken, C., Harrod, J., Mu, Y., and Samuel, E., “Redistribution reactions of alkoxy- and siloxysilanes, catalyzed by dimethyltitanocene,” Can. J. Chem., 1990, 68, 471-476.
Rahimian, K., Assink, R. and Loy, D., “Polymethylsilsesquioxanes through base-catalyzed redistribution of oligomethylhydridosiloxanes,” Polymer Preprints, American Chemical Society, 2000, 41(1), 512-513.
Rahimian, K., Assink, R., Lang, D., and Loy, D., “Polysilsesquioxanes through base-catalyzed redistribution of oligohydridosiloxanes,” Polymer Preprints, American Chemical Society, 2000, 41 (2), 1277-1278.
Loy Douglas A.
Rahimian Kamyar
Klavetter Elmer A.
Sandia Corporation
Shaver Paul F.
LandOfFree
Method for making polysilsesquioxanes and organohydridosilanes does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for making polysilsesquioxanes and organohydridosilanes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for making polysilsesquioxanes and organohydridosilanes will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2439230