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US 4,636,557 AGranted
Process for the preparation of aromatic polyethers with mixture of carbonate catalysts
AssigneeHoechst Aktiengesellschaft
InventorHellmuth Deckers
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Abstract
The invention relates to a process for the preparation of aromatic polyethers by condensation of the reactants in the presence of a condensation agent consisting of a mixture of metal carbonates comprising (a) lithium and/or an alkaline earth metal carbonate and (b) sodium, potassium, rubidium and/or cesium carbonate. The combination of carbonates (a) and (b) according to the invention leads to a surprising increase in activity.
Claims8
Process of preparing aromatic polyethers which comprises condensing diphenols and activated aromatic dihalogen compounds;
- polynuclear activated halogenophenols;
- or polynuclear activated halogenophenols, together with mixtures of dihydric phenols and activated aromatic dihalogen compounds, the molar ratio between diphenol and dihalogen being about 0.9 to 1.1:1
- in the presence of a condensation agent of at least one carbonate selected from the group consisting of lithium and alkaline earth metal carbonate, and
- at least one carbonate selected from the group consisting of sodium, potassium, rubidium and cesium carbonate,
- the condensation agent being in an amount of at least one mol of metal atoms per mol of hydroxyl.
2 more elements
Dependencies are inferred from the claim text.