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由三羟甲基丙烷三丙烯酸酯(TMPTA)和乙二胺(EDA)直接进行M ichael加成反应,合成端基为3个NH2的树枝状大分子G(NH2)3,用硬脂酰氯将其端氨基进行酰胺化得到端基为3个硬脂酰基的树枝状大分子GS(R)3,产率为82.4%。GS(R)3进一步与碘甲烷反应,其分子中的3个仲氨基被季铵化,生成树枝状季铵盐GI(R)3,产率为82.0%。讨论了反应温度、反应时间和原料配比对GS(R)3和GI(R)3产率的影响,并用红外、核磁和元素分析对GS(R)3和GI(R)3的结构进行表征。 相似文献
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Synthesis and antimicrobial activity of a perfluoroalkyl-containing quaternary ammonium salt 总被引:1,自引:0,他引:1
A novel perfluoroalkyl-containing quaternary ammonium salt 5 was designed and synthesized. Consequently, the antimicrobial activities of compound 5 were measured with Escherichia coli 8099 as a Gram-negative strain and Staphylococcus aureus ATCC 6538 as a Gram-positive strain. Both the minimum inhibitory concentration (MIC, the lowest concentration of compound 5 that inhibits microbial growth) values of quaternary ammonium salt 5 against Escherichia coli 8099 and Staphylococcus aureus ATCC 6538 were 7.8 μg/ml. 相似文献
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Eun-Seon Jeong Kyung-Hoon Kim Dae-Won Park Sang-Wook Park Jae-Wook Lee 《Reaction Kinetics and Catalysis Letters》2005,86(2):241-248
Summary The synthesis of dimethyl carbonate (DMC) was investigated through the transesterification of propylene carbonate (PC) with
methanol using quaternary ammonium salt catalysts. The reaction was carried out in an autoclave at 120-140 oC under carbon
dioxide pressure of 250-400 psig. The main by-product was propylene glycol. The quaternary salts of larger alkyl group and
more nucleophilic counter anion exhibited higher catalytic activity. Kinetic studies were also performed to better understand
the reaction mechanism. Quaternary ammonium chlorides immobilized on polystyrene supports were also tested for their possible
uses as heterogeneous catalysts. 相似文献
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Chonghui Wang Shigeo Nakamura 《Journal of polymer science. Part A, Polymer chemistry》1994,32(7):1255-1262
Triethyl-2,3-propanediolammonium chloride (TPC) was prepared and used for the preparation of polyester and copolyesters having quaternary ammonium groups in the side chains. The polycondensation of isophthaloyl dichloride with TPC and other dihydroxy compounds was performed by the organic phase/organic phase interfacial polycondensation method using N,N-dimethylacetamide/n-heptane or trimethyl phosphate/n-heptane as reaction media in the presence of tetramethyl ethylenediamine. Blend films were prepared from these polyesters and poly(vinyl alcohol) by casting from aqueous or aqueous NaOH solution. The electrical conductivity of the blend films is remarkably affected by the moisture content and in the order of 10?5 ~ 10?8 S/cm in the presence of moisture. © 1994 John Wiley & Sons, Inc. 相似文献
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A series of hydroxide conductive polymers QTBMs carryingdense aromatic side-chain quaternary ammonium groups has been synthesized by using a new monomer of 3,3′-di(3′′,5′′-dimethylphenyl)-4,4′-difluorodiphenyl sulfone and other commercial monomers via polycondensation reaction, and subsequent bromination, quaternization and alkalization.The chemical structures of the ionomers were confirmed by ~1H-and ~(13)C-NMR spectroscopy. Water uptake, swelling ratio, hydroxide conductivity, the number of bonded water per ammonium group(λ), volumetric ion exchange capacity(IEC_(Vwet)), mechanical and thermal properties, and chemical stability were systematically evaluated for the series of QTBMs membranes. QTBMs showed IECs ranging from1.02 meq·g~(-1)to 2.11 meq·g~(-1); in particular, QTBM-60 membrane with the highest IEC(2.11 meq·g~(-1)) had very high hydroxide ion conductivity of 131.9 m S·cm~(-1) at 80 °C, which was attributed to the well assembled nano-channels with distinct phase separation evidenced by small-angle X-ray scattering(SAXS). It was found that the hydrated QTBMs membranes were mechanically stable with moderate water uptakes and swelling ratios, high chemical stability under the harsh alkaline conditions. This work provides a facile way to prepare anion exchange membranes(AEMs) with high performances for the application in alkaline fuel cells. 相似文献
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Dae-Won Park Dong-Heon Ha Joo-Young Park Jeong-Yeul Moon Hwa-Soo Lee 《Reaction Kinetics and Catalysis Letters》2001,72(2):219-227
Aromatic polyester (PEA) and copolyesters having pendant carboxyl groups aredirectly synthesized from isophthaloyl chloride, diphenolic acid and diols byaqueous/organic two-phase interfacial polycondensation, using phase transfercatalysts. The yield and molecular weight of the polyester were remarkablyaffected by the structure of quaternary ammonium salts and crown ether catalysts.The phase transfer reaction steps are suggested to explain this phenomena. Theproperties of copolyesters were dependent on the original structure of diols. 相似文献
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合成了5种m-6-m型Gemini双季铵盐表面活性剂,在对产物结构和表面活性进行分析的基础上,分别采用紫外分光光度法和荧光分光光度法考察了m-6-m型Gemini双季铵盐表面活性剂与DNA的相互作用.结果表明,m-6-m型Gemini表面活性剂的CMC随烷基疏水链的增长呈逐渐下降趋势.几种表面活性剂均没有使DNA的紫外吸收峰发生红移或蓝移现象,说明复合物无嵌插作用或氢键形成,表面活性剂与DNA作用后的吸光度随表面活性剂浓度的增大而增强,当表面活性剂的浓度相同时,吸光度随疏水链的增大而逐渐减弱.Gemini表面活性剂浓度增大导致荧光强度降低,表面活性剂与DNA作用时的猝灭为静态猝灭,随着疏水链长度的增长,荧光猝灭常数降低,表面活性剂与DNA之间的作用力减弱. 相似文献
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Chonghui Wang Shigeo Nakamura 《Journal of polymer science. Part A, Polymer chemistry》1995,33(13):2157-2163
Aromatic polyester, copolyester, and poly(ester-amide-thioester) having pendant carboxyl groups are directly synthesized by the organic phase/water phase interfacial polyconden-sation using low-molecular and polymeric phase transfer catalysts. Spectral analysis of the resulting polymers indicates that the nucleophilicity of salts of phenols to diacid chloride is far higher than that of salts of carboxylic acids and chemoselective esterification occurs in a 100% yield. Even if the polymeric catalyst having amino acid moiety as a nucleophilic group is used in the polycondensation, the polymers do not contain anhydride groups. The polyester can be almost quantitatively converted to polymers with different reactive groups by reacting the pendant carboxyl groups with alkyl halides in a DMAc-H2O mixture con-taining K2CO3. A bifunctional catalytic mechanism is proposed for the chemical modification of the polyesters. © 1995 John Wiley & Sons, Inc. 相似文献
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Jang-Joo Kim Dong-Hwan Shin Hang-Soo Woo Dong-Ok Lim Dae-Won Park 《Reaction Kinetics and Catalysis Letters》2003,79(2):233-244
In the present study, the synthesis of (2-oxo-1,3-dioxolan-4-yl)methyl methacrylate (DOMA) from carbon dioxide and glycidyl
methacrylate (GMA) was investigated in a semi-batch reactor using macroporous polystyrene beads containing pendant quaternary
ammonium salt catalysts. The catalysts were prepared by partial copolymerization of styrene (ST) and divinylbenzene (DVB)
with isooctyl alcohol, and then by copolymerization with vinylbenzyl chloride (VBC). Quaternization of the pendant chloromethyl
groups was carried out by using trialkylamines. The catalytic activity of the macroporous polymer was influenced by VBC and
isooctyl alcohol concentration, and by the structure of trialkylamine. A kinetic study was also carried out to better understand
the reaction steps.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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Phosphodiesters quaternary ammonium salt (PQAS) displayed quite intense light scattering in aqueous solution under the optimum condition. In addition, the resonance light scattering (RLS) signal of PQAS was remarkably decreased after adding trace amount polysaccharide with the maximum peak located at 391 nm. It was found that the decreased RLS intensity of the PQAS − PPGL system (ΔIRLS) was in proportion to PPGL concentration in the range of 0.1-30 ng mL−1, with a lower detection limit of 0.05 ng mL−1. Based on this rare decreased RLS phenomenon, the novel method of the determination of purified polysaccharide of Gracilaria Lemaneiformis (PPGL) at nanogram level was proposed in this contribution. The proposed approach was used to determine purified polysaccharide extracted from Gracilaria Lemaneiformis with satisfactory results. Compared with the reported polysaccharide assays, this proposed method has good selectivity, high sensitivity and is especially simple and convenient. Moreover, the mechanism of the reaction between PQAS and polysaccharide was investigated by RLS, fluorescence, and fluorescence lifetime spectra. 相似文献
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The novel phase-transfer catalysts S-8 (dimethyloctyl(3-sulfopropyl) ammonium betaine) and DB-2 (di-active site quaternary
ammonium salts) were synthesized and employed as the phase-transfer catalysts for synthesizing thioethers from various alkyl
bromides of high conversion.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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A novel perfluorooctyl-containing quaternary ammonium salt was designed and synthesized, which was applied as a surface modification agent to provide the treated cotton fabrics with antimicrobial activity and low critical surface energy. 相似文献
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Pandurang N. Honkhambe Mahesh V. Biyani Manikrao M. Salunkhe 《European Polymer Journal》2010,46(4):709-1613
Three cardo bisphenols containing decahydronaphthalene group viz., 4,4′-(octahydro-2(1H)-naphthylidene)bisphenol, 4,4′-(octahydro-2(1H)-naphthylidene)bis-3-methylphenol and 4,4′-(octahydro-2(1H)-naphthylidene)bis-3,5-dimethylphenol were synthesized starting from commercially available 2-naphthol and were utilized for synthesis of new aromatic polyesters by phase transfer-catalyzed interfacial polycondensation with isophthaloyl chloride, terephthaloyl chloride and a mixture of isophthaloyl chloride and terephthaloyl chloride (50:50 mol %). Inherent viscosities and number average molecular weights (Mn) of polyesters were in the range 0.35-0.84 dL/g and 13,300-48,500 (Gel Permeation Chromatography, polystyrene standard), respectively. Polyesters were readily soluble in organic solvents such as dichloromethane, chloroform, tetrahydrofuran, meta-cresol, pyridine, N,N-dimethylformamide, N,N-dimethylacetamide, and 1-methyl-2-pyrrolidinone at room temperature and could be cast into tough, transparent and flexible films from their chloroform solutions. Wide-angle X-ray diffraction measurements revealed the amorphous nature of polyesters. The glass transition temperature of polyesters was in the range 207-287 °C. The temperature at 10% weight loss (T10), determined from thermogravimetric analysis of polyesters, was in the range 425-460 °C indicating their good thermal stability. 相似文献