Synthesis, optical, and thermal properties of polyimides containing flexible ether linkage

Abstract

The goal of this article was to synthesize a series of flexible polyimides containing ether linkage in main chain and clarified the effect of this ether linkage on some physical properties such as optical and thermal decomposition. Also, different functional group effects such as carbonyl (CO), hexa‐fluoro‐isopropylidene [C(CF3)2] and phenyl (C6H5) on these physical properties were evaluated. The structural characterization of poly(ether imide)s was performed using Fourier transform infrared, 1H‐nuclear magnetic resonance (NMR), and 13C‐NMR techniques. Optical band gap of polyimides was calculated in the range from 2.57 to 2.81 eV. Thermal characterization of poly(ether imide)s was carried out using thermogravimetry–differential thermal analysis and differential scanning calorimetry. Thermal stability of poly(ether imide)s was evaluated by initial decomposition temperature (Ton) and char. Ton value of polymers was determined in the range from 100 to 195 °C. In addition, glass transition temperatures of poly(ether imide)s were found between 144 and 148 °C. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46573.

The retarding effects and structural evolution of a bio‐based high‐performance polyimide during thermal imidization

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Poly(azomethine‐imide)s containing siloxane moities: Optical, thermal, mechanical, and morphological properties

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New transparent and thermally stable cardo poly(ether imide)s derived from 10,10-bis[4-(4-amino-2-pyridinoxy)phenyl]-9(10H)-anthrone

“…Certainly, the incorporation of pyridine ring could also increase their solubility, which was due to the pyridine ring nitrogen atom in the structure produces a polarized bond and increases dipole–dipole interactions in the polymer–solvent system, further improving the polymer solubility. 30 Besides, their solubility was also affected by the rigidity of the used dianhydride monomers. For example, PEI- 6c and PEI- 6e are soluble in common organic solvents such as N -methyl-2-pyrrolidone, DMF, DMAc, and pyridine, even in low boiling point solvent like THF for PEI- 6e at room temperature because of the presence of the more flexible ether linkages and hexafluoroisopropylidene units, respectively.…”

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