• Bulletin of the Korean Chemical Society
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• v.28 no.9
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• pp.1567-1572
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• 2007

New pyrrolidinium and piperidinium bis(trifluoromethanesulfonyl)imide (TFSI) ionic liquids (ILs) having allyl substituents were synthesized and characterized. All of them are liquid at room temperature and stable up to 300 oC. The pyrrolidinium-based ILs showed better conductivities and lower viscosities than the corresponding piperidinium-based ILs. Among them, 1-allyl-1-methylpyrrolidinium TFSI showed the lowest viscosity of 52 cP, the highest conductivity of 5.7 mS cm?1, and the most negative cathodic voltage window of ?3.2 V (vs. Fc/Fc+) on a platinum electrode, which are the improved results compared to the corresponding analogue having a saturated substituent, 1-methyl-1-propylpyrrolidinium TFSI.

• Bulletin of the Korean Chemical Society
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• v.22 no.1
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• pp.25-29
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• 2001

Nucleophilic substitution reactions of O-imidomethyl derivatives of phenols with OH- were studied theoretically using the semiempirical AM1 and Solvation Model 2.1 (SM2.1) methods in the gas phase and aqueous solution, respectively. In the gas phase, the two reaction paths, in which the imide (1a) or phenol (1b) is functioning as a leaving group, can occur competitively. In contrast, in aqueous solution, path (1b) becomes more favorable than (1a) because the transition states (TS) of path (1b) are more stabilized by solvent. Differences in solvation energies are caused by the structural differences of TS, i.e., the TS via path (1b) is more dissociative than that via path (1a). Therefore we conclude that the solvent effects play an important role in the hydrolysis of O-imidomethyl derivatives of phenols. However, reactivity is dependent on the acidities of both the imide and the phenol fragments since the ρz values vary progressively from 4.2 (Z' = I) to 2.5 (Z' = IV) as the acidities of imide increase. These are in good agreement with the experimental results.

• Macromolecular Research
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• v.17 no.11
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• pp.912-918
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• 2009

An optically active diacid containing the L-histidine moiety was prepared by reacting pyromellitic dianhydride (1,2,4,5-benzenetetracarboxylic acid 1,2,4,5-dianhydride) 1 with L-histidine 2 in acetic acid, and was polymerized with several aromatic diamines 5a-g to obtain a new series of optically active poly(amide-imide)s (PAIs) using two different methods, such as direct polycondensation in a medium consisting of N-methyl-2-pyrrolidone (NMP)/triphenyl phosphite (TPP)/calcium chloride ($CaCl_2$)/pyridine (Py) and direct polycondensation in a tosyl chloride (TsCl)/pyridine (Py)/N,N-dimethylformamide (DMF) system as a condensation agent. The resulting new polymers 6a-g with inherent viscosity was obtained in good yield. The polymers were readily soluble in polar organic solvents, such as N,N-dimethyacetamide (DMAc), N,N-dimethyformamide (DMF), and dimethyl sulfoxide (DMSO). The obtained polymers were characterized by FTIR, specific rotation, elemental analysis as well as $^1$H-NMR spectroscopy and gel permeation chromatography (GPC). The thermal stability of the resulting PAIs was evaluated with thermogravimetric analysis techniques under a nitrogen atmosphere.

• Advances in nano research
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• v.14 no.2
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• pp.201-210
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• 2023

A ZnO/poly (amide-imide) hybrid nanocomposite film with different weight percentages of Zinc oxide (ZnO) nanoparticles is synthesized and characterized in this paper. A two-step reaction successfully synthesized a new kind of heteroaromatic diamine with bulky pendant groups. In order to produce 3, 5-dinitro-3, 3-bis (4-(4-Nitrophenoxy) phenyl) -2- benzofuran-1-one, 3, 3'-bis (4-hydroxyphenyl) benzofuran-1-one and 3'-bis (4-hydroxyphenyl) benzofuran-1-one were combined with 3'-bis (3-hydroxyphenyl) benzofuran-1-one. The obtained dinitro was then reduced by zinc dust and hydrochloric acid. The reaction of 4, 4^* carbonyl diphthalic anhydride with amino acid L-alanine in acetic acid leads to the production of very high yields of chiral diacid monomer. As a result of the direct polymerization of these monomers, new optically active polymers were formed (amide-imide). In order to synthesize poly (amide-imide)/ZnO nanocomposites with different weight percentages (2, 4, 6, 8, and 10%), PAI and ZnO nanoparticles were combined using ultrasonication SEM, Fourier transform infrared spectroscopy, X-ray diffraction and thermal gravimetry were used to characterize the PAI films.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2004.11a
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• pp.72-72
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• 2004

• Proceedings of the Korean Fiber Society Conference
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• 1995.04a
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• pp.21-21
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• 1995

• Proceedings of the Membrane Society of Korea Conference
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• 2000.11a
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• pp.39-42
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• 2000

• Proceedings of the Korean Society of Potoscience Conference
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• 2005.06a
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• pp.27-28
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• 2005

• Bulletin of the Korean Chemical Society
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• v.18 no.8
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• pp.899-902
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• 1997

• Bulletin of the Korean Chemical Society
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• v.18 no.4
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• pp.441-442
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• 1997