Kinetics of Imidization and Crosslinking for Afr700B Polyimide

摘要

The imidization kinetics for AFR700B polyimide were determined using Fourier transfore infrated spectroscopy (FTIR) by following the increase in imide groups as tracked with the 1360 cm~-1 band over several isotherms. Imidization occurs at an rapid initial rate, followed by a slow rate. The reaction rates for both the fast and slow regions were found to be first order with respect to the increase in the 1360 cm~-1 band. The activeation energy and preexponetial fctor were found for each region. The formation of imide rings in AFR700B was found to occur until approximately 300degC. This was confirmed by the rpesence of water up to 300degC in thermogravimetric analysis-mass spectroscopy data. Literature has shown that imidization is mass transfer limited. Thus, the kinetics should be coupled with a mass transfer relation to accurately describe the imidization reaction.