Synthesis and characterization of new diacid monomers and poly (ester-imide) s: a study of thermal property relationship and solubility

Two dicarboxylic acids [2,2'-(((4-hydroxyphenyl) methylene) bis (3-Bromo-4,1- phenylene)) bis (1,3 dioxoisoindoline 5 carboxylic acid)) and 2,2 '(((2,4dichlorophenyl) methylene) bis (4,1-phenylene)) bis (1,3-dioxoisoindoline-5-carboxylic acid)] were made by the reaction of pyromellitic anhydride (PMDA) with diamine in a solvent of g pyridine/glacial acetic acid at refluxing temperature. The organization of the diacid monomers is defined by FTIR and 1H-NMR spectroscopy. The sequence of new poly (ester-imide) s are arranged of two di acids and aromatic diols: [Bis (4hydroxyphenyl) 2 furelmethaneand 4,4'((1,4phenylene (methanylyidene)) bis (azanylylidene)) diphenol] by employing the polycondensation in the company of the dibutyltine dilaurate as a catalyst. The PEIs were defined by FTIR, 1HNMR, and TGA. Poly (ester-imide) s showed excellent solubility in polar aprotic solutions because of the existence of flexible groups in the polymer backbone. Furthermore, they displayed better thermal constancy, and the heat at that 10% loss of weight happened about700 to 800°C.