Synthesis and properties of organosoluble polyimides based on novel flourene-ring containing diacetamido-diamine

Synthesis of aromatic, soluble, and thermally stable polyamides derived from new diamine containing unsymmetrical phenolphthalein and imidazole pendent group

A novel diamine monomer containing unsymmetrical phenolphthalein and triaryl imidazole pendant group, 3,3-bis(4-(4-amino-2-(4,5-diphenyl-1H-imidazol-2-yl)phenoxy)phenyl)isobenzofuran-1(3H)-one (BADPPI), was successfully prepared in three steps. The novel diamine monomer BADPPI was directly polymerized with commercially available diacids, such as terephthalic acid, isophthalic acid, pyridine-2,6-dicarboxylic acid, and adipic acid, to obtain corresponding polyamides (PAs). The resulting novel aromatic PAs were obtained in high yields and moderate inherent viscosities in the range of 0.52–0.57 dL g−1 and exhibited excellent solubility in aprotic polar solvents, such as N,N-dimethylacetamide , N-methyl-2-pyrrolidone, N,N-dimethylformamide, dimethyl sulfoxide, tetrahydrofuran, meta cresol, and pyridine. PAs showed high glass-transition temperatures between 191°C and 277°C. Thermogravimetric analysis of the PAs indicated a 10% weight loss ( T10%) in the temperature range of 382–473°C and char yields at 600°C under nitrogen atmosphere in the range of 56–70% depending on the diacids monomer used for the PAs preparation.

Asymmetric-based novel poly(ether-imide)s: Preparation, properties, kinetics of thermal decomposition, and study electrochemical oxidation behavior by using nanocomposite paste of polymer and multi-walled carbon nanotube

A series of novel fluorescent poly(ether-imide)s (PEIs) bearing ether linkage and diarylimidazole pendant in the backbone was successfully prepared by polycondensation reaction between a new unsymmetrical diamine and commercially available tetracarboxylic acid dianhydrides. The PEIs were characterized by Fourier transform infrared, 1H-NMR, UV-vis spectroscopy, fluorimetry, scanning electron microscopy and elemental analysis. The PEIs with inherent viscosities in the range of 0.47–0.63 dL g−1 showed excellent solubility in various aprotic solvents such as N-methylpyrrolidone, dimethyl sulfoxide, N, N-dimethylacetamide and N,N-dimethylformamide. Thermal properties of new PEIs were evaluated by differential scanning calorimetric and thermogravimetric analysis in N2 and air. These polymers showed glass transition temperatures ( Tg) in the range of 269–333 °C and 10% weight loss temperatures above 400 °C in air atmosphere. The data obtained from TGA experiments of these polymers have been applied in different kinetic equations such as Coats–Redfern, Kissinger and Criado methods, to determine the kinetic parameters ( E, ▵ S, ▵ G, ▵ H) and mechanism of thermal decomposition. Herein a method based on the adsorptive stripping cyclic voltammetry technique to investigate electrochemical oxidation of these polymers by using multi-walled carbon nano tubes modified glass electrode is also reported.