Phthalic Anhydride → Phthalimide

Participants

Reaction Steps

A phthalimide-amine was prepared by mixing in a 2 liter glass resin kettle equipped with a mechanical stirrer, a heating mantle, a thermocouple connected to a temperature recorder, and an overhead water trap with a vertical condenser, 2.0 moles (600 grams) of BABA (a product of the E. I. duPont de Nemours & Company containing primarily 2,4-Bis(p-aminobenzyl)aniline) and 3.0 moles (444 grams) of phthalic anhydride. Heat was applied, and at about 100° C., the BABA melted and phthalic anhydride started slowly to react. The temperature was slowly allowed to rise to 150° C., at which time water began to condense overhead. Heating continued until 3.0 moles (54 grams) of water were collected. Since 2.0 moles of BABA contain 6 primary amines and three of them reacted with phthalic anhydride to form phthalimide linkages, 3 primary amine groups remained per 2 moles of BABA phthalimide. Since the molecular weight of this BABA phthalimide is 300+222-27=495, and contains 3 aminic hydrogens, its amine equivalent is 495/3=165, which corresponds to one epoxide equivalent or 180 grams of EPON-828 or 826 (the diglycidel ether of bisphenol-A such as is produced by the Shell Corporation). In other words, 47 grams of the aromatic amine of this example correspond to 51.3 grams of EPON-828.

Provenance & Evidence