Journal of Polymer Science Part A: Polymer Chemistry, Vol.41, No.24, 3974-3988, 2003
Synthesis and characterization of novel, optically active poly(amide-imide)s from N,N'-(4,4'-sulfonediphthaloyl)-bis-L-phenylalanine diacid chloride and aromatic diamines under microwave irradiation
3,3',4,4'-Diphenylsulfonetetracarboxylic dianhydride was reacted with L-phenylalanine in acetic acid, and the resulting imide acid (3) was obtained in high yield. The diacid chloride (4) was obtained from its diacid derivative (3) by reaction with thionyl chloride. The polycondensation reaction of 4 with several aromatic diamines such as 4,4'-sulfonyldianiline, 4,4'-diaminodiphenyl methane, 4,4'-diaminodiphenylether, p-phenylenediamine, m-phenylenediamine, 2,4-diaminotoluene, and 1,5-diaminonaphthalene was developed with a domestic microwave oven in the presence of trimethylsilyl chloride and a small amount of a polar organic medium such as o-cresol. The polymerization reactions were also performed with two other methods: low-temperature solution polycondensation in the presence of trimethylsilyl chloride and reflux conditions. A series of optically active poly(amide-imide)s with moderate inherent viscosities of 0.21-0.42 dL/g were obtained in high yield. All of the aforementioned polymers were fully characterized by IR, H-1 NMR elemental analyses, and specific rotation techniques. Some structural characterizations and physical properties of these optically active poly(amide-imide) s are reported. (C) 2003 Wiley Periodicals, Inc.
Keywords:microwave-assisted polycondensation;optically active polymers;poly(amide-imide)s;microwave oven;inherent viscosity;polyimides;polyamides;thermagravimetric analysis (TGA);polycondensation