摘要 |
<p>A method is provided for converting aromatic bis(ether N-organo substituted phthalimides) to aromatic bis(ether anhydrides) by heating a bisphasic aqueous-organic mixture of aromatic bis(ether N-organo substituted phthalimide), phthalic anhydride and an exchange catalyst to effect an imide-anhydride exchange producing an aqueous phase containing aromatic bis(ether phthalic acid) and an organic phase containing N-organo substituted phthalimide. The aromatic bis(ether phthalic acid) is then optionally dehydrated to the corresponding anhydride.</p> |