Hossein Behniafar, Sara Haghighat
Dec 1, 2006
Citations
0
Influential Citations
17
Citations
Journal
European Polymer Journal
Abstract
Abstract An imide ring-containing diamide–dianhydride, N -[3,5-bis(3,4-dicarboxybenzamido)phenyl]phthalimide dianhydride ( 1 ) was prepared by the reaction of trimellitic anhydride chloride with N -(3,5-diaminophenyl)phthalimide in a medium consisting of methylene chloride and pyridine. A series of new alternating aromatic poly(amide-imide)s having inherent viscosities of 0.26–0.37 dl/g was synthesized using a two-step poly(amic-acid) precursor method. A reference monomer, 1,3-bis(3,4-dicarboxybenzamido)benzene dianhydride ( 2 ) without the phthalimido pendant group attached to the polymer main chain was prepared in order to study the structure-property relationship. In this case, the structure effects on some properties of the resulting poly(amide-imide)s including crystallinity, solubility, thermal stability, and film flexibility could be easily clarified. A diamide–triimide ( 3 ) as a model compound was also synthesized by the reaction of new dianhydride 1 with aniline to compare the characterization data as well as to optimize the polymerization conditions. The resulting polymers were fully characterized by FT-IR, UV–visible and 1 H NMR spectroscopy. Most of the polymers showed an amorphous nature and were readily soluble in a variety of organic solvents such as N , N -dimethylacetamide (DMAc), N , N -dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N -methyl-2-pyrrolidone (NMP), and pyridine. The glass-transition temperatures of these polymers were recorded between 301 and 371 °C. All polymers showed no significant weight loss below 500 °C in nitrogen, and the decomposition temperatures at 10 wt.% loss range from 506 to 543 °C. The films of the resulting poly(amide-imide)s could be cast from their NMP solutions, and the transparency and flexibility of them were investigated.