Method of making aromatic dihydroxy diacid dihalides and precipitates resulting therefrom
OwnerKiu-Seung Leeinventor
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Abstract
A method of making an aromatic dihydroxy diacid dihalide comprises forming a solution of an aromatic dihydroxy diacid in a solvent, contacting the aromatic dihydroxy diacid solution with a halogenating agent; heating the solution under an inert atmosphere to convert from 50 and 100 percent of the aromatic dihydroxy diacid to aromatic dihydroxy diacid dihalide, wherein the time required for the conversion is less than 4 hours, and removing at least a portion of the solvent.
Claims10
A method of making an aromatic dihydroxy diacid dihalide, comprising:
- a) forming a solution of an aromatic dihydroxy diacid in a cyclic ether solvent with the provisio that the dihydroxy diacid dichloride formed in step (c) is soluble in the solvent;
- b) contacting the aromatic dihydroxy diacid solution with a halogenating agent;
- c) heating the solution under an inert atmosphere to convert from 50 to 100 weight percent of the aromatic dihydroxy diacid to aromatic dihydroxy diacid dihalide wherein the time for the conversion is less than 4 hours, and
- d) removing at least a portion of the cyclic ether solvent.
A purified aromatic dihydroxy diacid dihalide composition containing 1 to 25 weight percent aliphatic solvent when stored at about 25 degrees Celsius under Nitrogen atmosphere for 168 hours results in less than 1 percent of the aromatic dihydroxy diacid dihalide self polymerizing.
Dependencies are inferred from the claim text.