Method of purifying dianhydrides

A method of preparing a purified dianhydride is provided where said method comprises the steps of preparing a first mixture comprising water, at least one inorganic acid, and at least one dianhydride, said dianhydride comprising at least one impurity which is soluble in aqueous acid heating said fir...

Full description

Saved in:
Bibliographic Details
Main Authors KLOPPENBURG LIOBA MARIA, NAMJOSHI ABHIJIT, WHITNEY JOHN MORGAN, PRESSMAN ERIC JAMES, OULMAN SPENCER THOMAS
Format Patent
LanguageEnglish
Published 24.02.2009
Subjects
CHEMISTRY
HETEROCYCLIC COMPOUNDS
METALLURGY
ORGANIC CHEMISTRY
Online AccessGet full text

Cover

More Information
Summary:A method of preparing a purified dianhydride is provided where said method comprises the steps of preparing a first mixture comprising water, at least one inorganic acid, and at least one dianhydride, said dianhydride comprising at least one impurity which is soluble in aqueous acid heating said first mixture until substantially all of said dianhydride is converted to a tetraacid comprised in a second mixture; filtering at least a portion of said second mixture to provide a solid tetraacid and a filtrate, said filtrate comprising at least a portion of said impurity; and heating the tetraacid provided in a solvent with concurrent distillation of water to provide a third mixture comprising a purified dianhydride and a solvent.
Bibliography:Application Number: US20040022905