http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Synthesis and characterization of soluble polyimides functionalized with carbazole moieties
Mathews, Anu Stella,Kim, Dongjo,Kim, Youngkyoo,Kim, Il,Ha, Chang-Sik Wiley Subscription Services, Inc., A Wiley Company 2008 Journal of polymer science Part A, Polymer chemist Vol.46 No.24
<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. <img src='wiley_img/0887624X-2008-46-24-POLA23109-gra001.gif' alt='wiley_img/0887624X-2008-46-24-POLA23109-gra001'> </P>
Mathews, Anu Stella,Kim, Il,Ha, Chang-Sik Wiley Subscription Services, Inc., A Wiley Company 2006 Journal of applied polymer science Vol.102 No.4
<P>We have synthesized a series of fully aliphatic polyimides (APIs) from bicyclo[2,2,2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride (BOCA) and various aliphatic diamines, including linear aliphatic, flexible alicyclic, and rigid adamantyl diamines. We performed the polymerization reactions using one-step syntheses in m-cresol at elevated temperatures without the isolation of poly(amic) acid. The chemical composition and structure of the polymers were characterized by nuclear magnetic resonance (NMR) and infrared (IR) spectrometry. The characterization data are reported from analyses using gel permeation chromatography (GPC), thermogravimetric analysis (TGA), differential scanning calorimeter (DSC), and wide-angle X-ray diffraction (WXAD) measurements. The polyimides are also subjected to solubility, solution viscosity, tensile strength, transparency, and dielectric constant measurements. The resultant polyimides possess well-controlled molecular weight, reasonable intrinsic viscosity, good transparency, enhanced solubility, low dielectric constants, and high glass transition temperature, together with marginal thermal and mechanical stability. These properties were enhanced in copolyimides containing equimolar amounts of rigid and flexible moieties. These rigid-rod APIs derived from the alicyclic dianhydride and aliphatic diamines are promising candidates as advanced materials for future applications in micro- and photoelectronic devices. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3316–3326, 2006</P>
Mathews Anu Stella,Kim Il,Ha Chang-Sik The Polymer Society of Korea 2007 Macromolecular Research Vol.15 No.2
Polyimides are one of the most important classes of polymers used in the microelectronics and photoelectronics industries. Because of their high thermal stability, chemical resistance, and good mechanical and electric properties, polyimides are often applied in photoresists, passivation and dielectric films, soft print circuit boards, and alignment films within displays. Recently, fully aliphatic and alicyclic polyimides have found applications as optoelectronics and inter layer dielectric materials, due to their good transparencies and low dielectric constants $(\varepsilon)$. The low molecular density, polarity and rare probability of forming inter- or intra-molecular charge transfers, resulting in lowering of the dielectric constant and high transparency, are the most striking characteristics of aliphatic polyimide. However, the ultimate end use of polyimides derived from aliphatic monomers is in their targeted applications that need less stringent thermal requirements. Much research effort has been exerted in the development of aliphatic polyimide with increased thermal and mechanical stabilities, while maintaining their transparencies and low dielectric constants, by the incorporation of rigid moieties. In this article, the recent research process in synthesizing fully aliphatic polyimides, with improved dimensional stability, high transparency and low $\delta$values, as well as the characterizations and future scope for their application in micro electric and photo-electronic industries, is reviewed.
Fully Aliphatic Polyimides – Influence of Adamantane and Siloxane Moieties
Mathews, Anu Stella,Kim, Il,Ha, Chang-Sik WILEY-VCH Verlag 2007 Macromolecular symposia Vol.249 No.1
<P>Series of fully aliphatic polyimides were prepared from cyclobutane- 1,2,3,4-tetracarboxylic dianhydride and aliphatic diamines. The variations of the basic properties of these polyimides as a result of the incorporation of adamantyl and siloxane moieties are examined. The structure of the polyimides where confirmed by FT-IR spectroscopy. It was found that polyimides with appropriate ratio of adamantane and siloxane groups showed excellent solubility, good thermal stability, high glass transition temperature, low dielectric constant and beneficial transparencies.</P>