Purification of 4, 4' Diaminophenyl Ether
Original Publication Date: 1989-Dec-01
Included in the Prior Art Database: 2005-Jan-31
A special recrystallization process has been proposed to purify 4, 4' diaminophenyl ether (DAPE), commonly known as oxydianiline (ODA), prior to its being used to manufacture polyamic acid ethyl ester (PAETE). The method is simple, economical and effective in providing a high quality material free of oxidation products.