Synthesis and characterization of soluble polyimides functionalized with carbazole moieties

다국어 초록 (Multilingual Abstract)

<P>Here, we report the synthesis and characterization of new soluble polyimides that are functionalized using carbazole moieties in their side chain. As a monomer for synthesizing the polyimides, 4″-carbazole-9-yl-[1,1′;2′,1″] terphenyl-4-4′-diamine and 2-(3-carbazol-9-yl-propyl)-biphenyl-4,4′-diamine were synthesized and then characterized using <SUP>1</SUP>H NMR, <SUP>13</SUP>C NMR, FTIR, UV–visible and photoluminescence spectroscopy, differential scanning calorimetry (DSC), and elemental analysis. The polyimides synthesized via chemical imidization processes were characterized with X-ray photoelectron spectroscopy, gel permeation chromatography, wide angle X-ray diffraction, thermogravimetric analysis, DSC, tensile strength measurement, and dielectric property measurement. Results showed that the synthesized polyimides were soluble in a variety of organic solvents, optically transparent in a visible range, thermally stable, mechanically strong, and considerably low dielectric. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 8117–8130, 2008</P>
<B>Graphic Abstract</B>
<P>We report here new soluble semiconducting polyimides (PIs) containing carbazole moieties in the side chain. For dianydrides were used pyromellitic anhydride (PMDA) or 2, 2′-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (6FDA). The carbazole diamine derivatives are 4″-carbazole-9-yl-[1,1′;2′,1″] terphenyl-4-4′-diamine (CzTPDA) and 2-(3-carbazol-9-yl-propyl)-biphenyl-4,4′-diamine (CzHBPDA). All PIs showed high mechanical strength (>1.5 GPa) and extremely high glass transition temperature (>260 °C). Interestingly, most of PIs exhibited low dielectric constant below 3, whilstile the PI films were optically transparent in the visible range (>∼400 nm). Here are structures of CzTPDA and CzHBPDA synthesized in this work.
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