Synthesis, characterization, and thermal properties of anhydride terminated and allyl terminated oligoimides

Abstract

This study concerns the synthesis of anhydride terminated oligoimides (ANTOI) and allyl terminated oligoimides (ALTOI), in acetic acid medium, which allows a very fast reaction and an easy working out. For the preparation of ALTOIs, two methods are compared: the first one consists of adding the monofunctional compound (allyl amine) to the ANTOI already formed during a first step by reaction of a dianhydride (excess) and a diamine. The second method consists of a “one pot” reaction between the dianhydride, the diamine, and the monofunctional allyl–amine compounds, at the beginning of the reaction. The experimental results show that the best control of the molecular weights is obtained with the first method. If the amount of allyl amine is higher than the amount necessary to end cap the ANTOI, a transimidization reaction occurs. Thermal analyses of oligoimides terminated by anhydride or allyl groups have been performed by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Transition and thermoresistance properties make ANTOI and ALTOI derivatives interesting as precursors for block polyimide copolymers. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 2993–3003, 2000