Synthesis and characterization of organosoluble optically active poly(ester-imide)s derived from trimellitic anhydride, L-methionine and bisphenols

The reaction of thionyl chloride in pyridine as a condensing agent was used for the direct polycondensation of N-trimellitylimido-L-methionine (4) with various aromatic diols such as bisphenol A (5a), phenolphthalein (5b), 1,5-naphthalendiol (5c), 2,6-dihydroxytoluene (5d), hydroquinone (5e), biphenyl-2,2'-diol (5f), 1,4-dihydroxyanthraquinone (5g). This reaction leads to the formation of novel optically active poly(ester-imide)s (PEI) s. The resulting PEIs were obtained in good yields and exhibited low to moderate inherent viscosities ranging from 0.15 to 0.40 dL g(-1). All of the PEIs showed good solubility and readily dissolved in solvents such as N-methyl-2-pyrrolidinone (NMP), N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), pyridine and tetrahydrofuran. Thermogravimetric analysis showed that PEI 6b was stable, with 10% weight loss recorded above 370 degrees C in nitrogen. All of the above polymers were characterized by FTIR, specific rotation, and representative PEIs were also characterized by (1)H NMR, elemental analysis, and thermogravimetric analysis. The structural characterization and physical properties of these new optically active PEIs are reported.