Kinetic investigations of formation of polyimides containing arylene sulfone ether linkages by potentiometric titration and their characterization

Autor: Özdemir Özarslan, Hande Güçlü, Tülay Yilmaz, Attila Güngör, Abdülkadir Kuyulu, Emel Yıldız, Ekrem Ekinci
Rok vydání: 1997
Předmět:
Zdroj: Journal of Polymer Science Part A: Polymer Chemistry. 35:2981-2990
ISSN: 1099-0518
0887-624X
Popis: In this work, thermal solution imidization kinetics of two high performance polyimides, prepared from the polycondensation of pyromellitic dianhydride (PMDA) and 3,3*,4,4*-benzophenonetetracarboxylic dianhydride (BTDA) with 4,4*-bis(3- aminophenoxy)diphenylsulfone (DAPDS) were investigated using nonaqueous titra- tion technique with tetramethylammonium hydroxide. Most of the kinetic investiga- tions, found in the literature, are based on the aromatic p-diamines. 1,2 In the present work, attention was focused on imidization kinetics with m-substituted aromatic di- amines having electron donating ({O{) and electron withdrawing ({SO2{) groups in the same molecule. Kinetic parameters, namely the rate constants, activation energ- ies, entropies and enthalpies of imidization reactions were determined and compared with the literature values. It is reported in literature 3 that electron affinities of dianhy- drides and ionization potentials of diamines, have strong influence on the reaction rate and activation energies of imidization. Activation energy (Ea) values were found to be 66 and 57 kJ/mol for DAPDS/PMDA and DAPDS/BTDA respectively, and order of reaction was found to be second order. Polyimides DAPDS/PMDA and DAPDS/BTDA, subjected to kinetic investigation, showed glass transition temperatures of 2677C and 2417C, both were found to be thermally stable up to 5007C. q 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2981-2990, 1997
Databáze: OpenAIRE
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