Process for preparing polyarylene polyethers and a novel polyarylene polyether
AssigneeUnion Carbide Corporation
InventorsThomas H. Schwab, Wong F. Ark, Robert A. Clendinning
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AssigneeUnion Carbide Corporation
InventorsThomas H. Schwab, Wong F. Ark, Robert A. Clendinning
Estimating the term…
Described herein is an improved process for preparing polyarylene polyethers by (a) converting a dihydric phenol to the alkali metal phenolate by adding an alkali metal or alkali metal compound to the phenol in a mixture of a sulfone or sulfoxide solvent and a solvent which forms an azeotrope with water, (b) removing water by codistillation with the azeotrope forming cosolvent, and (c) reacting the phenolate mixture with a dihalobenzeneoid compound, wherein a lighter colored product is obtained by adding the sulfone or sulfoxide solvent in increments. This may be accompanied by (1) adding an increment of the sulfone or sulfoxide solvent to a mixture of the dihydric phenol in the codistillation solvent and adding the remaining portion during the azeotroping step, or (2) adding an increment of the sulfone or sulfoxide solvent to the mixture of dihydric phenol and codistillation solvent and the remaining portion to the system simultaneously with the alkali metal hydroxide or other phenolate forming alkali metal source, or (3) adding a first increment of the sulfone or sulfoxide to the dihydric phenol-azeotrope forming solvent prior to step (a), a second increment simultaneously with the addition of alkali metal source in step (a), and the remainder during or at the end of azeotroping step (b).
An improved process for preparing polyarylene polyethers which comprises the steps of:
A polyarylene polyether having a color factor less than about 20.
Dependencies are inferred from the claim text.