Preparation and Characterization of Polyimide Obtained from BPDA

Three kinds of linear polyimide containing flexible structure of diamine based on biphenyldianhydride, 4,4'-oxidiamine(4,4'-ODA),3,4'-oxidiamine(3,4'-ODA) and 1,3-bis(4-ami nophenoxy) benzene(1,3,4-APB) were synthesized in N N-dimethyl acetamide via transition polymerization.The chemical structures of them were characterized by Fourier transform infrared spectroscopic(FT-IR).High thermal resistant properties were analyzed by thermal gravimetric analysis(TG) which shows the temperatures of degradation of them are all above 500℃and polyimide(PI) derived from 4,4'-oxidiamine(4,4'-ODA) possesses the highest decomposed temperature.Dynamic mechanical analysis indicates that PI derived from 1,3-bis(4-aminophenoxy) benzene(1,3,4-APB-PI) has the lowest glass transition temperature.Influences of different solvents and water content on lap shear strength and various chain structures on adhesion and high heat resistant properties were also investigated in this study.