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چکیده
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Six new optically active poly(amide-imide)s (PAIs) with good inherent viscosities were synthesized from the direct polycondensation reaction of N-trimellitylimido-L-amino acids with 1,2-bis[4-aminophenoxy]ethane by direct polycondensation in a medium consisting of N-methyl-2-pyrrolidone (NMP)/triphenyl phosphite (TPP)/calcium chloride (CaCl2)/pyridine (py). Diamine was synthesized by using a two-step reaction. At first 1,2-bis[4-nitrophenoxy] ethane was prepared from the reaction of two equimolars 4-nitrophenol and one equimolar 1,2-dibromo ethane and the dinitro compound was reduced by using Pd/C. Also N-trimellitylimido-L-amino acids were synthesized by the condensation reaction of trimellitic anhydride with two equimolars of various L-amino acids in acetic acid solution. The polymerization reactions produced a series of optically active PAIs with a high yield and good inherent viscosity. The resulted polymers were fully characterized by means of FTIR and H-1 NMR spectroscopy, elemental analyses, inherent viscosity, specific rotation, solubility tests, thermogravimetric analysis (TGA), and a derivative of thermogravimetric (DTG) analysis. (C) 2011 Production and hosting by Elsevier B.V. on behalf of King Saud University.
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