Synthesis and Characterization Organosoluble Optically Active Poly(ester-imide)s Derived from Trimellitic anhydride, L-Methionine and Different 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 o 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 activePEIs are reported.