Process for preparing titanates and zirconates
AssigneeCentre National De La Recherche Scientifique
InventorsJean-Claude Bernier, Paul J. L. Poix, Jean L. Rehspringer
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Abstract
The invention concerns a process for preparing titanates and zirconates respectively of formulas MTiO.sub.3 and MZrO.sub.3 where M is Ba.sup.2+, Sr.sup.2+, Ca.sup.2+, Pb.sup.2+ and Mg.sup.2+ to the exclusion of MgZro.sub.3, consisting of reacting an ester of formula M[H-(CH.sub.2).sub.n CO.sub.2 ].sub.2 where n=1-4 with the formula M'[O(CH.sub.2).sub.n CH.sub.2).sub.n CH.sub.3 ].sub.4 where M' is Ti or Zr bringing the reaction mixture to boil until the solvent is removed to yield a viscous translucent resin. The resin is cooled and further treated to obtain the desired product.
Claims13
A process for preparing titanates and zirconates respectively of formulas MTiO.sub.3 and MZrO.sub.3 wherein M is a divalent metal selected from the group consisting of barium, strontium, calcium, lead and magnesium to the exclusion of MgZrO.sub.3, comprising:
- preparing an ester of the formula:
- M (RCOO).sub.2
- wherein R is an alkyl or a substituted alkyl radical containing 1 to 4 carbon atoms by attack of a salt of the metal, with an organic acid of the formula:
- R--COOH
- wherein R has the designation given above, the ester being soluble in its corresponding acid,
- reacting said ester in solution in its corresponding acid with an alkoxide of, the formula:
- M'(OR').sub.4
- wherein M' is Ti or Zr and R' is an alkyl or a substituted alkyl radical containing 1 to 5 carbon atoms, the reaction resulting in a clear solution,
- bringing to boil the reaction mixture until the solvent is removed to yield a viscous, translucent resin,
- solidifying said resin by cooling,
- crushing said resin or reducing it to a powder by the addition of liquid nitrogen, and
- subjecting said resin to a slow pyrolysis.
Dependencies are inferred from the claim text.