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A series of polyazomethines (PAM-01, PAM-02, PAM-03) containing various amounts of tetraphenylthiophene-oxazole (TPTP-o) moieties were produced by the polycondensation of a diamine precursor (TPTP-o) with equimolar proportions of two aromatic dialdehydes [isophthalaldehyde (1,3 IPA) and terephthalaldehyde (1,4 TPA)]. The TPTP-o precursor was successfully synthesized in three steps. The synthesized TPTP-o and the polymers (PAM-01, PAM-02, PAM-03) were characterized by ultraviolet–visible (UV–Vis) spectroscopy, FT-IR spectroscopy, x-ray diffraction (XRD), 1H-NMR, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) techniques. The effects of the TPTP-o units in the PAM on the insertion with azo linkages were studied with respect to conductivity and thermal stability. The room-temperature DC electrical conductivity of the PAM films was found to range from 9.59 × 10−7 S/cm to 9.73 × 10−7 S/cm. UV absorption at 342 nm confirmed the formation of azo (–C=N–) linkages in the polymer, which is helpful for electron conductivity throughout the polymer network. All three PAMs had a glass transition temperature (Tg) between 260°C and 267°C, and T10% thermal degradation values of thermally stable polyazomethines were in the range of 517–530°C. All three PAMs showed moderate solubility in organic solvents and inherent viscosity of between 0.31 dL/g and 0.35 dL/g. The XRD study indicated that all three PAMs were amorphous in nature, with a broad peak in the vicinity of 20°. [ABSTRACT FROM AUTHOR]

Here we report a new five polyamides prepared via solution-phase polycondensation under Yamazaki-Higashi conditions to prove the suitability of this method. The synthesized polyamides were characterized by FTIR, 1H-NMR, differential scanning calorimetry, thermogravimetric analysis, inherent viscosity, solubility and wettability tests. These polyamides were amorphous in nature and they are completely soluble in many organic solvents and they could easily be solution-cast into transparent, flexible films. The as-prepaired polymers showed excellent thermal properties. The glass transition temperatures of these polymers are in the range of 251–274 °C under nitrogen atmosphere. The decomposition temperature in nitrogen for a 10% weight-loss temperature is more than 744 °C, and char yield at 900 °C ranged from 43 to 56% in nitrogen. Water contact angles were also tested to know the hydrophilicity of the polyamide films. As-synthesized polyamides showed smallest quantact angles indicating hydrophilic surface. [ABSTRACT FROM AUTHOR]

2,5-Bis(4-(2-aminothiazole) phenyl)-3,4-diphenyl furan (BATPDF), well prepared in four steps. Novel aromatic polyimides containing tetraphenylfuran-thiazole unit were synthesized via a two-step thermal imidization derived from BATPDF with various commercially available dianhydrides such as pyromellitic dianhydride (PMDA), 3,3′,4,4′-biphenyltetracarboxylic dianhydride (BPDA), 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BTDA), 4,4′-oxydi (phthalic anhydride) (ODPA) and 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA). The resulting aromatic PIs were obtained in high yields and moderate inherent viscosities in the range of 0.42-0.48 dL g−1 and were practically amorphous as shown by the X-ray diffraction studies. All the polyimides exhibited excellent solubility in solvents, such as DMAc, NMP, m-cresol and pyridine on heating. PIs showed high glass transition temperatures between 238 and 252 °C. TG of the PIs indicated a 10% mass loss (T10%) in the temperature range of 518-609 °C and char yields at 900 °C under nitrogen atmosphere in the range of 58-65% depending on the dianhydrides monomer used for the synthesis PIs. The structure-property correlation between these polyimides was studied. In view of these polymer's potential applications as thermally stable aerospace, optoelectronics and microelectronics device. [ABSTRACT FROM AUTHOR]