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Journal articles on the topic 'Quaternary ammonium bromide (QBr)'

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Published: 4 June 2021

Last updated: 19 February 2022

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1

Kim, Hyeonjeong, Dayoung Jung, Jiseon Hwang, Junghyun Chae, and Jinho Chang. "Probing the speciation of quaternary ammonium polybromides by voltammetric tribromide titration." Analyst 143, no. 17 (2018): 4017–21. http://dx.doi.org/10.1039/c8an00560e.

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2

Davey, Tim W., William A. Ducker, Alan R. Hayman, and Jim Simpson. "Krafft Temperature Depression in Quaternary Ammonium Bromide Surfactants." Langmuir 14, no. 12 (June 1998): 3210–13. http://dx.doi.org/10.1021/la9711894.

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3

Stefańska, Justyna, Anna Pietruczuk-Padzik, Marta Struga, Maciej Borkowski, and Stefan Tyski. "Biological Evaluation of Quaternary bis Ammonium Salt and Cetylpyridinum Bromide Against S. epidermidis biofilm." Polish Journal of Microbiology 62, no. 4 (2013): 359–64. http://dx.doi.org/10.33073/pjm-2013-049.

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Quaternary ammonium compounds are broad-spectrum bacteriocides widely used as antiseptics, disinfection and preservation agents. The aim of this study was to examine the activity of two quaternary ammonium salts, cetylpyridinum bromide and a newly synthesized quaternary bis ammonium salt, against S. epidermidis biofilm. The average values of killing efficiency for cetylpyridinum bromide ranged from 26.6% to 64.1% for all tested concentrations (0.125 to 8.0 microg x mL(-1)) and for quaternary bis ammonium salt the percentage of killing efficiency ranged from 59.7% to 88.4% for tested concentrations (from 2.0 to 128.0 microg x mL(-1)). Both tested compounds significantly affect staphylococcal biofilms, but any of used concentrations caused a total eradication of bacterial biofilm.

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4

Yoshimura, Tomokazu, Hiroaki Yoshida, Akiko Ohno, and Kunio Esumi. "Physicochemical properties of quaternary ammonium bromide-type trimeric surfactants." Journal of Colloid and Interface Science 267, no. 1 (November 2003): 167–72. http://dx.doi.org/10.1016/s0021-9797(03)00694-5.

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5

Betz, Richard, and Peter Klüfers. "N-(2-Iodophenylmethyl)hexamethylenetetraminium bromide dihydrate." Acta Crystallographica Section E Structure Reports Online 63, no. 11 (October 10, 2007): o4279. http://dx.doi.org/10.1107/s1600536807048623.

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The title compound, C13H18IN4 +·Br−·2H2O, is a quaternary ammonium salt derived from 2-iodobenzyl bromide and hexamethylenetetramine. Two water molecules per asymmetric unit act as hydrogen-bond donors to the bromide anion. Direct cation–anion contacts are established via C—H donors, mainly from methylene groups in the α position to the ammonium centre.

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6

Vega, Daniel, and Ricardo Baggio. "A new polymorphic form of Otilonium Bromide." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C1576. http://dx.doi.org/10.1107/s205327331408423x.

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"Otilonium bromide (C29H43 N2 O4+.Br-) is a quaternary ammonium derivative which has been proven a potent spasmolytic drug with a good tolerability profile, used in the treatment of irritable bowel syndrome. We present herein the structural analysis of an unreported polymorphic form (I), comparing with the only one known so far and already reported [1] polymorphic form of the compound (II). The data set for I was obtained from a twinned specimen. The poor quality of the data thus available did not pose any problem in the structure resolution, but it did instead in refinement: the alkyloxy chains and ethyl branches in the quaternary ammonium groups needed some continuity restraints in their anisotropic displacement factors. In form II this effect appeared enhanced, ending up in unusually large anisotropic displacement parameters for most atoms in the chain. The main points of molecular disagreement reside in the torsion angles where the alkyloxy chains and quaternary ammonium groups leave the planar mainframe. The only notorious intermolecular contacts in both structures appear to be a number of rather weak C–H···Br ones involving the quaternary ammonium groups somehow ""wrapping"" the bromide counterion. There are a few C–H···O contacts interlinking molecules to each other. The phase transformation occurs at 124(2)°C and can be followed by DSC and XRPD. A detailed analysis shows some features in common, viz., in both structures packing stability is mainly due to the ionic interaction between the N+ and the Br-, with the latter ion being evenly surrounded by a number of ammonium groups in a way that they define regular 2D arrays "sandwiching" the neutral part of the molecules, which thus act as spacers. These similarities allow giving a plausibility argument about the way in which the transition may take place."

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7

Kulič, Jiří, Jiří Sussenbek, and Aleš Ptáček. "Alkaline Hydrolysis of Substituted Phenyl Acetates Catalyzed by Quaternary Ammonium Salts." Collection of Czechoslovak Chemical Communications 58, no. 12 (1993): 2891–95. http://dx.doi.org/10.1135/cccc19932891.

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Alkaline hydrolysis if the phenyl acetates CH3COOC6H4X (X = 4-NO2, 3-NO2, 3-Cl, H, 4-CH3, 3-CH3, and 4-OCH3) in the presence of hexadecyltris(2-hydroxyethyl)ammonium chloride, bis(2-hydroxyethyl)hexadecyl(methyl)ammonium bromide, and hexadecyltrimethylammonium bromide has been studied. Comparison of the rates of the hydrolysis for the above tenzides showed that the most efficient catalyst is the hexadecyltris(2-hydroxyethyl)ammonium chloride. In all cases, the rate data correlated well with structure effects by the Hammett equation.

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8

Mikláš, R., N. Miklášová, M. Bukovský, and F. Devínsky. "Synthesis and antimicrobial properties of binaphthyl derived quaternary ammonium bromides." Acta Facultatis Pharmaceuticae Universitatis Comenianae 59, no. 1 (January 1, 2012): 39–47. http://dx.doi.org/10.2478/v10219-012-0017-5.

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Synthesis and antimicrobial properties of binaphthyl derived quaternary ammonium bromides(S)-N-(2-(4,5-dihydro-3H-dinaphtho[2,1-c:1',2'-e]azepin-1-yl)ethyl)-N, N-dimethyl-N-dodecyl ammonium bromide (S)-1a and (S)-N-(2-(4,5-dihydro-3H-dinaphtho[2,1-c:1',2'-e]azepin-1-yl)ethyl)-N, N-dimethyl-N-tetradecylammonium bromide (S)-1b have been synthesized as optically active quaternary ammonium salts starting from 1,1'-binaphthyl-2,2'-diol. Their antimicrobial activity expressed as minimal inhibition concentration (MIC) was tested against Gram-positive human pathogenic bacteria S. Aureus, Gram-negative bacteria E. coli and human fungal pathogen C. Albicans.

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9

Matsuoka, Keisuke, Naohiro Takahashi, Shiho Yada, and Tomokazu Yoshimura. "Solubilization ability of star-shaped trimeric quaternary ammonium bromide surfactant." Journal of Molecular Liquids 291 (October 2019): 111254. http://dx.doi.org/10.1016/j.molliq.2019.111254.

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10

Sun, Hong Juan, Tong Jiang Peng, Hai Feng Liu, and Jin Mei Sun. "XRD Study of Hydrophlogopite Intercalated with Alkyl Quaternary Ammonium Salt." Advanced Materials Research 178 (December 2010): 330–35. http://dx.doi.org/10.4028/www.scientific.net/amr.178.330.

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Hydrophlogopite was modified with sodium and then organically intercalated with a series of alkyl quaternary ammonium salts. The organically intercalated samples were characterized by X-ray diffraction analysis (XRD) and the effect of alkyl quaternary ammonium salt on the interlayer spacing of hydrophlogopite was discussed. The results showed that if the same alkyl quaternary ammonium salt was used to intercalate hydrophlogopite, the interlayer spacing of hydrophlogopite increased gradually with the rise of the added amount of quaternary ammonium salt, and that if different quaternary ammonium salts with the same amount were used, the interlayer spacing increased gradually with the rise of the chain length of the alkyl quaternary ammonium salts. For the alkyl quaternary ammonium salts with large chain length (n>10), the inflection point for the increasing interlayer spacing of the intercalated hydrophlogopite is at about 0.5 times of CEC. When octadecyl trimethyl ammonium bromide is used as intercalation agent and the added amount is 5 times of CEC, the interlayer spacing of hydrophlogopite is relatively maximal.

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11

Davey, Tim W., and Alan R. Hayman. "Synthesis of ω-Hydroxy Quaternary Ammonium Bolaform Surfactants." Australian Journal of Chemistry 51, no. 7 (1998): 581. http://dx.doi.org/10.1071/c98001.

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Several members of a novel class of w-substituted asymmetric bolaform surfactants have been synthesized in order to investigate their surfactant and biological properties. The ω-hydroxy trialkylammonium and pyridinium surfactants have significant antimicrobial and antifungal activity relative to their conventional analogues. For conventional quaternary ammonium alkyl surfactants, increasing the hydrocarbon chain length causes a decrease in the surfactant monomer solubility and a corresponding decrease in the biological activity. No such trend is observed for the ω-hydroxy quaternary ammonium bromide series.

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12

Gamal, Mohammed. "Analytical review: analytical techniques for hyoscine N butyl bromide." Analyst 145, no. 6 (2020): 2025–37. http://dx.doi.org/10.1039/d0an00076k.

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13

Nowak, Łukasz, Magdalena Regel-Rosocka, Barbara Marszałkowska, and Maciej Wiśniewski. "Removal of Zn(II) from chloride acidic solutions with hydrophobic quaternary salts." Polish Journal of Chemical Technology 12, no. 3 (January 1, 2010): 24–28. http://dx.doi.org/10.2478/v10026-010-0028-8.

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Removal of Zn(II) from chloride acidic solutions with hydrophobic quaternary salts The equilibrium of zinc(II) extraction from hydrochloric acid solutions with phosphonium and ammonium quaternary salts and their application as carriers in polymer inclusion membranes were studied. The most efficient was the extraction of zinc with the use of chlorides and bromide of ammonium and phosphonium salt (more than 90%). Quaternary ammonium and phosphonium chlorides and bromide are efficient extractants of zinc(II) from hydrochloric acid solutions. Two-fold molar excess of extractant over Zn(II) is necessary for efficient extraction (100%). Solvent extraction power of the extractants studied decreases with increasing hydrophobicity of the anion in the following sequence: QPCl > QPBr > QPBis > QACl > QABF4 > QPBF4 > QPPF6 > QPNtf2. A solution of 1 M H2 SO4 is chosen as the best stripping phase from the technological and economical point of view. Transport across polymeric inclusion membrane enables concentration of the stripping solution; however it takes a very long time.

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14

Yoshimura, Tomokazu, Takumi Kusano, Hiroki Iwase, Mitsuhiro Shibayama, Tetsuya Ogawa, and Hiroki Kurata. "Star-Shaped Trimeric Quaternary Ammonium Bromide Surfactants: Adsorption and Aggregation Properties." Langmuir 28, no. 25 (June 14, 2012): 9322–31. http://dx.doi.org/10.1021/la301220y.

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15

Jendric, M., N. Filipović‐Vinceković, M. Vinceković, M. Bujan, and I. Primožić. "Phase Behavior of Bis(Quaternary Ammonium Bromide)/Sodium Cholate/H2O System." Journal of Dispersion Science and Technology 26, no. 1 (January 2005): 39–51. http://dx.doi.org/10.1081/dis-200040213.

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16

Howard, Leah, Rashed Almousa, and Dong Xie. "Polyurethane surface modified with a hydrophilic polymer containing quaternary ammonium bromide." Emergent Materials 3, no. 5 (May 14, 2020): 637–48. http://dx.doi.org/10.1007/s42247-020-00104-2.

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17

Mohammed, Makhloufia, BenaÏssa Tahar, Derdour AÏcha, and Henni Djamel Eddine. "Antibacterial Activity of Quaternary Ammonium Salt from Diethylaminoethyl Methacrylate." E-Journal of Chemistry 7, s1 (2010): S61—S66. http://dx.doi.org/10.1155/2010/637549.

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A quaternary ammonium salt was synthesized from diethylaminoethyl methacrylate (DEAEMA) by quaternization with hexadecyl bromide. The resultant compound (Am-h) was characterized by FTIR and NMR spectroscopy. Its bactericidal activity was evaluated by determining minimum inhibitory concentration (MIC) values and inhibitory zone diameter against gram positive bacteria (Streptococcus sp.) and gram negative bacteria such asAcenito baumannii, Klebsiella pneumoniaeandProteus sp. respectively. The results showed that the MIC values of the synthesised compound (Am-h) were 2 μg/mL againstAcenito baumannii, Klebsiella pneumoniae, Proteus sp. and Streptococcus sp.

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18

Bai, Li, La-Jun Feng, Hong-Yan Wang, Yong-Bin Lu, Xiao-Wei Lei, and Fang-Lin Bai. "Comparison of the synergistic effect of counterions on the inhibition of mild steel corrosion in acid solution: electrochemical, gravimetric and thermodynamic studies." RSC Advances 5, no. 6 (2015): 4716–26. http://dx.doi.org/10.1039/c4ra12286k.

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19

Wang, Yanhua, Chanjuan Gao, and Shengke Yang. "The association effect of quaternary ammonium salt on carboxymethyl cellulose and its analytical applications." Water Science and Technology 72, no. 6 (May 26, 2015): 837–43. http://dx.doi.org/10.2166/wst.2015.266.

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Sodium carboxymethyl cellulose (CMC) has been extensively used in petroleum, geology, common household chemicals, food, medicine and other industries, owing to its excellent water-soluble, emulsifying, water retention and film forming properties. It is known as ‘industrial monosodium glutamate’. However, the research of the test method on CMC is far behind the research of its actual application value. This study showed that, weak acid or weak basic medium, the carboxyl groups dissociated from CMC, existing as a big negative ion, which can form ion-association complexes with some quaternary ammonium cations through electrostatic and hydrophobic interactions. The absorption spectrum changes and Triton-X100 can increase the sensitivity of the system. The maximum absorption wavelengths are, respectively, about 256 nm for dodecyl trimethyl ammonium bromide (LTAB), 244 nm for tetradecyltrimethyl ammonium bromide (TTAB) and 240 nm for cetyltrimethyl ammonium bromide (CTAB) with CMC. The reactions show very high sensitivities and the maximum molar absorption coefficients are 1.10 × 104 L/(mol·cm) for LTAB system, 1.24 × 106 L/(mol·cm) for TTAB system and 1.78 × 106 L/(mol·cm) for CTAB system. This method is simple and rapid, and can be applied for the spectrophotometric determination of trace CMC in the supernatant of centrifuged drilling mud.

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20

Zhou, Fei, Wei Lu, Zhen Zhang, and Jiu Ling Meng. "Graft of Bis-QAC to Cotton Fiber and its Antibacterial Characteristics." Applied Mechanics and Materials 633-634 (September 2014): 468–71. http://dx.doi.org/10.4028/www.scientific.net/amm.633-634.468.

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The bis-type quaternary ammonium salts (bis-QAC) with hydroxyl group in their molecules, 4,5-Bis (alkyl dimethyl ammonium bromide)-1-pentanol were immobilized on cotton fiber to prepare an antibacterial cotton fibers (called as Ws) by using a coupling agent, tetramethoxysilane. The antibacterial characteristics of Ws were investigated. 4,5-Bis (alkyl dimethyl ammonium bromide)-1-pentanol chemically bonded to the surface of cotton fiber exhibited antimicrobial activity against a broad range of microorganism. Their antibacterial activity was not easily influenced by environmental pH and temperature, and could not be removed from the surface of wool by repeated washing.

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21

In, Martin, Veronique Bec, Olivier Aguerre-Chariol, and Raoul Zana. "Quaternary Ammonium Bromide Surfactant Oligomers in Aqueous Solution: Self-Association and Microstructure†." Langmuir 16, no. 1 (January 2000): 141–48. http://dx.doi.org/10.1021/la990645g.

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22

Jiang, Rong, Shuang Wang, and Jinping Li. "Cucurbit[7]uril–tetraphenylethene host–guest system induced emission activity." RSC Advances 6, no. 6 (2016): 4478–82. http://dx.doi.org/10.1039/c5ra24264a.

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A host–guest complex was successfully constructed from cucurbit[7]uril (Q[7]) and quaternary ammonium-modified tetraphenylethene derivative, 1,1,2,2-tetrakis{2-[2-(N,N,N-trimethylammonium)ethyoxyl]phenyl}-tetraphenylethene bromide (TAPET).

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23

Mathiazzi, Beatriz Ideriha, and Ana Maria Carmona-Ribeiro. "Hybrid Nanoparticles of Poly (Methyl Methacrylate) and Antimicrobial Quaternary Ammonium Surfactants." Pharmaceutics 12, no. 4 (April 10, 2020): 340. http://dx.doi.org/10.3390/pharmaceutics12040340.

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Quaternary ammonium surfactants (QACs) are microbicides, whereas poly (acrylates) are biocompatible polymers. Here, the physical and antimicrobial properties of two QACs, cetyl trimethyl ammonium bromide (CTAB) or dioctadecyl dimethyl ammonium bromide (DODAB) in poly (methyl methacrylate) (PMMA) nanoparticles (NPs) are compared to those of QACs alone. Methyl methacrylate (MMA) polymerization using DODAB or CTAB as emulsifiers and initiator azobisisobutyronitrile (AIBN) yielded cationic, nanometric, homodisperse, and stable NPs. NPs’ physical and antimicrobial properties were assessed from dynamic light scattering (DLS), scanning electron microscopy, and viability curves of Escherichia coli, Staphylococcus aureus, or Candida albicans determined as log(colony-forming unities counting) over a range of [QACs]. NPs were spherical and homodisperse but activity for free QACs was higher than those for QACs in NPs. Inhibition halos against bacteria and yeast were observed only for free or incorporated CTAB in NPs because PMMA/CTAB NPs controlled the CTAB release. DODAB displayed fungicidal activity against C. albicans since DODAB bilayer disks could penetrate the outer glycoproteins fungus layer. The physical properties and stability of the cationic NPs highlighted their potential to combine with other bioactive molecules for further applications in drug and vaccine delivery.

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24

Lukáč, Miloš, Ivan Lacko, Marián Bukovský, Zuzana Kyselová, Janka Karlovská, Branislav Horváth, and Ferdinand Devínsky. "Synthesis and antimicrobial activity of a series of optically active quaternary ammonium salts derived from phenylalanine." Open Chemistry 8, no. 1 (February 1, 2010): 194–201. http://dx.doi.org/10.2478/s11532-009-0126-8.

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AbstractWe synthesized nine quaternary ammonium compounds (QUATs) starting from phenylalanine, N-alkyl-N,N-dimethyl-(1-hydroxy-3-phenylpropyl)-2-ammonium bromides, which were prepared as optically pure substances. Five compounds were prepared as S-enantiomers and four compounds as R-enantiomers. These compounds were evaluated by their activities against bacteria and fungi. Three microbial strains were used in the study: the gram-negative bacteria Escherichia coli, the gram-positive bacteria Staphylococcus aureus and the fungi Candida albicans. The activities were expressed as minimum bactericidal or fungicidal concentrations (MBC). The most active compounds were (2S)-N-tetradecyl-N,N-dimethyl-(1-hydroxy-3-phenylpropyl)-2-ammonium bromide and (2R)-N-tetradecyl-N,N-dimethyl-(1-hydroxy-3-phenylpropyl)-2-ammonium bromide, with MBC values exceeding those of commercial benzalkoniumbromide (BAB) used as standard. The relationships between structure and biological activity of the tested QUATs were quantified by the bilinear model (QSAR) and are discussed.

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25

Barbosa, Renata, Dayanne Diniz Souza, Edcleide Maria Araújo, and Tomás Jefférson Alves de Mélo. "Systematic Characterization of Different Quaternary Ammonium Salts to be Used in Organoclays." Materials Science Forum 727-728 (August 2012): 1552–56. http://dx.doi.org/10.4028/www.scientific.net/msf.727-728.1552.

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Studies of degradation have verified that the decomposition of some quaternary ammonium salts can begin to be significant at the temperature of about 180 ° C and like most thermoplastics are processed at least around this temperature, the thermal stability of the salt in clay should always be considered. Some salts are more stable than others, being necessary to study the degradation mechanisms of each case. In this work, four quaternary ammonium salts were characterized by differential scanning calorimetry (DSC) and thermogravimetry (TG). The results of DSC and TG showed that the salts based chloride (Cl-) anion begin to degrade at similar temperatures, while the salt based bromide (Br-) anion degrades at higher temperature. Subsequently, a quaternary ammonium salt was chosen to be used in organoclays, depending on its chemical structure and its thermal behavior.

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26

Bolshakov, Aleksei, Arno J. F. van Hoof, Brahim Mezari, Nikolay Kosinov, and Emiel Hensen. "A versatile mono-quaternary ammonium salt as a mesoporogen for the synthesis of hierarchical zeolites." Catalysis Science & Technology 9, no. 23 (2019): 6737–48. http://dx.doi.org/10.1039/c9cy02001b.

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Here we report a versatile method to synthesize hierarchically porous zeolites with FER, CHA and MFI topologies by using inexpensive mono-quaternary ammonium N-cetyl-N-methylpyrrolidinium (C₁₆NMP) bromide as a mesoporogen.

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27

Wang, Yefei, Zhen Yang, Fengtao Zhan, Zhifeng LYu, Chengyou Han, Xiaonuo Wang, Wuhua Chen, Mingchen Ding, Renzhuo Wang, and Yingnan Jiang. "Correction: Indolizine quaternary ammonium salt inhibitors part II: a reinvestigation of an old-fashioned strong acid corrosion inhibitor phenacyl quinolinium bromide and its indolizine derivative." New Journal of Chemistry 43, no. 43 (2019): 17123–24. http://dx.doi.org/10.1039/c9nj90149c.

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Correction for ‘Indolizine quaternary ammonium salt inhibitors part II: a reinvestigation of an old-fashioned strong acid corrosion inhibitor phenacyl quinolinium bromide and its indolizine derivative’ by Yefei Wang et al., New J. Chem., 2018, 42, 12977–12989.

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28

Zhou, Fei, and Jing Zheng. "Surface Modification for Cotton Fiber and its Antimicrobial Characteristics." Advanced Materials Research 311-313 (August 2011): 2067–70. http://dx.doi.org/10.4028/www.scientific.net/amr.311-313.2067.

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Quaternary ammonium compounds, Couple, Cotton fiber, Antibacterial activity. Abstract. a gemini-type quaternary ammonium compound with a hydroxyl group in their spacer chain, 4,5-bis(dodecyl dimethyl ammonium bromide)-1-pentanol (called as DAP12), was immobilized on the surface of cotton fiber by using a silane coupler, tetraethoxysilane and a novel antibacterial cotton fiber (called as CF12) was prepared. Antibacterial characteristics of CF12 were investigated comparatively with [3-(trimethoxysilyl) propyl] octadecyldimethylammonium chloride(TPOAC), a mono-type quaternary ammonium salt. CF12 had excellent antibacterial characteristics in the wide range of environmental pH and temperature, which is not weakened even if 30 times repetitive use. The experimental results indicated also that CF12 has higher antimicrobial activity than TPOAC immobilized on the surface of cotton fiber against a broad range of microorganisms, and average inhibition ratio against 15 strains of gram-negative, gram-positive bacteria and yeasts is 99.0% at 30 °C and pH 6.0.

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29

Kleszczyńska, Halina, Janusz Sarapuk, Małgorzata Oświęcimska, and Stanisław Witek. "Antioxidative Activity of Some Quaternary Ammonium Salts Incorporated into Erythrocyte Membranes." Zeitschrift für Naturforschung C 55, no. 11-12 (December 1, 2000): 976–80. http://dx.doi.org/10.1515/znc-2000-11-1221.

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The antioxidative activity of two series of amphiphilic compounds from a group of quaternary ammonium salts has been investigated. They were so-called bifunctional surfactants synthesized to be used as common pesticides or as antioxidants. The latter application was to be ensured by providing the compounds studied with an antioxidant group. Studies on antioxidative possibilities of those compounds were performed on pig erythrocytes. Due to their hydrophobic parts, they anchor in the erythrocyte membrane and influence the degree of lipid oxidation in the erythrocyte membrane subjected to UV radiation. It was found that compounds of both series decreased the oxidation of the membrane lipids. The inhibition of this oxidation increased with the length of their hydrophobic chains up to fourteen carbon atoms. The compounds of the longest hydrophobic chains showed a somewhat weaker antioxidative activity. Of the two series studied compounds were more effective having bromide ions as counterions. The corresponding compounds of a second series (chlorides) protected erythrocyte significantly weaker against oxidation. The effect of the compounds on fluidity of the erythrocyte membrane has been studied in order to explain the oxidation results. Change in fluidity of the erythrocyte ghost membranes was found also dependent on length of the hydrophobic part of the compounds and was more pronounced in the case of bromide surfactants. The final conclusion is that the compounds studied can be succesfully used as antioxidant agents of good efficacy.

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30

Sivamani, Jayaraman, Veeramanoharan Ashokkumar, Velu Sadhasivam, Kumaraguru Duraimurugan, and Ayyanar Siva. "Ultrasonic assisted dimeric cinchona based chiral phase transfer catalysts for highly enanatioselective synthesis of epoxidation of α,β-unsaturated ketones." RSC Adv. 4, no. 104 (2014): 60293–99. http://dx.doi.org/10.1039/c4ra10952j.

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New types of bis-quaternary ammonium bromide as chiral multisite phase transfer catalysts derived from cinchona alkaloids have been developed and evaluated for the enantioselective epoxidation of chalcones in the presence of lower concentrations of various oxidants, bases and ultrasonic irradiation conditions.

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31

Franklin, Kevin R., and Barrie M. Lowe. "Crystallization of silica molecular sieves from piperazine — quaternary ammonium bromide — silica — water systems." Zeolites 8, no. 6 (November 1988): 501–7. http://dx.doi.org/10.1016/s0144-2449(88)80227-6.

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32

Cho, Iwhan, and Chung-Soo Kim. "NEW SYNTHETIC VESICLES FORMED BY POLYMERIC QUATERNARY AMMONIUM BROMIDE WITH DOUBLE ALKYL CHAINS." Chemistry Letters 14, no. 10 (October 5, 1985): 1543–44. http://dx.doi.org/10.1246/cl.1985.1543.

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33

Shane, Hillary L., Ewa Lukomska, Aleksandr B. Stefaniak, and Stacey E. Anderson. "Divergent hypersensitivity responses following topical application of the quaternary ammonium compound, didecyldimethylammonium bromide." Journal of Immunotoxicology 14, no. 1 (January 1, 2017): 204–14. http://dx.doi.org/10.1080/1547691x.2017.1397826.

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34

Müller, Anneliese, Kathrin Rychli, Andreas Zaiser, Cornelia Wieser, Martin Wagner, and Stephan Schmitz-Esser. "TheListeria monocytogenestransposon Tn6188provides increased tolerance to various quaternary ammonium compounds and ethidium bromide." FEMS Microbiology Letters 361, no. 2 (October 31, 2014): 166–73. http://dx.doi.org/10.1111/1574-6968.12626.

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35

Adem, Prof Dr Georgius A., and Zaydoon K. Kreamid. "Preparation of De-emulsifier of Gemini Surfactant & it's Application in Oil Industry." Journal of Petroleum Research and Studies 1, no. 1 (May 5, 2021): 30–36. http://dx.doi.org/10.52716/jprs.v1i1.25.

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A Gemini surfactants (GS) which are bis quaternary ammonium salt. It is prepared from tetramethyl ethylene diamine (TMEDA) with cetyl bromide, while an ordinary surfactant (OS),which is quaternary ammonium salt, is prepared from trimethyl amine (TMA) and cetyl bromide. They were identified by elemental analysis and IR spectroscopy. Comparing the GS,OS and the commercial surfactants, the Gemini surfactant shows an interesting properties and have a variety of uses, such as a De-emulsifier. Adopting the composition ratios found in the study of reverse chemistry of commercial De-emulsifier, Rp 6000, which is usually use in the south and north oil companies in Iraq. The prepares active gradients were characterized by various techniques, IR spectroscopy, elemental analysis, melting point, solubility, flash point and functional group analysis. The efficiency of the prepared De-emulsifier was examined by standard methods and compared with the efficiency of commercial Rp 6000 based on the same wet crude oil sources.

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36

Koula, Václav, Daria Kučová, and Jiří Gasparič. "Determination of Organic Bases by Ion-Pair Extraction Polarography Using Orange II as Counter Ion." Collection of Czechoslovak Chemical Communications 57, no. 11 (1992): 2272–78. http://dx.doi.org/10.1135/cccc19922272.

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The combination of ion-pair extraction and differential pulse polarography is shown to be a method suitable for the determination of 10-7 mol l-1 concentrations of organic bases of quaternary ammonium compounds. Orange II (4-[2-hydroxy-1-naphtyl]azobenzenesulfonic acid) was found to be an appropriate polarographically active counter-ion. The proposed method was used for the determination of tetrapentylammonium bromide (as model compound), Septonex ([1-(ethoxycarbonyl)-pentadecyl]trimethylammonium bromide) and codeine.

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37

Hao, Xia, Zhen Xu, Na Li, Nian Bing Li, and Hong Qun Luo. "A cation exchange based electrochemical sensor for cetyltrimethylammonium bromide detection using an acridine orange/polystyrene sulfonate system." Analytical Methods 7, no. 9 (2015): 3849–54. http://dx.doi.org/10.1039/c5ay00815h.

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38

Matveichuk, Yulya V. "NITRATE-SELECTIVE ELECTRODE AND ITS USE FOR ANALYSIS OF VEGETABLES AND MINERAL WATERS." IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 62, no. 9 (August 30, 2019): 20–26. http://dx.doi.org/10.6060/ivkkt.20196209.6004.

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The effect of the length of the radicals at the exchange center of the quaternary ammonium salts on the selectivity and the detection limit of the nitrate-selective electrode is investigated. The observed effects of improving the analytical characteristics while reducing the steric availability of the exchange center for quaternary ammonium salts are explained on the basis of the theory of ion association. The composition of the polyvinyl chloride (33 wt.%) electrode membrane for the quaternary ammonium salt (3,4,5-tris bromide (dodecyloxy)benzyltricethylammonium bromide, 5 wt.%) and the plasticizer (o-nitrophendecyl ether, 62 wt.%) was optimized. The developed electrode has a low detection limit (2.0∙10−7 mol/l) and a close to theoretical slope of the electrode function (56.8 mV/pNO3), and the potential of the nitrate-selective electrode is not affected by fluoride, nitrite, bicarbonate-, dihydrophosphate-, sulfate ions. The interfering action of chloride, bromide, and iodide ions can be eliminated by introducing 1·10–3 mol/l of a background solution of silver sulfate. Thiocyanate and perchlorate ions interfere with the operation of the electrode, but they are practically not found in real objects. The developed electrode was used to determine the nitrate ions in vegetables (white cabbage, cucumber, lettuce, tomato, onion, carrots, and potatoes), greens (dill, parsley) and mineral water. It was established that the maximum permissible concentration of nitrates is exceeded more than 4.5 times for cabbage (MAC = 500 mg/kg), almost 2 times for salad (maximum permissible concentration 1500 mg/kg), 1.5 times for potatoes (maximum permissible concentration 250 mg/kg) and 3 times for dill (maximum permissible concentration 1500 mg/kg).

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39

Khan, Khalid M., Zafar S. Saifyb, Abdullah Khan, Mansoor Ahmed, Muhammed Saeed, Raid J. Abdel-Jalil, Gerald Griibler, and Wolfgang Voelter. "Syntheses of Selected Quaternary Phenacylbromopyridinium Compounds and their Biological Evaluation." Zeitschrift für Naturforschung B 54, no. 9 (September 1, 1999): 1210–18. http://dx.doi.org/10.1515/znb-1999-0920.

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The studies, presented here, deal with the synthetic modification of 5-bromonicotinic acid on its nitrogen nucleus. The synthetic transformations were carried out by reacting equimolar amounts of 5-bromonicotinic acid and phenacyl halides in acetone. A range of phenacyl halides were used with the objective of getting a variety of quaternary ammonium salts of 5- bromonicotinic acid derivatives as multipurpose biologically active compounds. Twelve quaternary ammonium salts of 5-bromonicotinic acid have been synthesized and tested for cytotoxicity, antibacterial and antifungal activities. These compounds showed promising cytotoxicity against Artemia salina. Two compounds, 3-carboxy-1-(4′-methylphenacyl)-5-bromopyridinium bromide (2) and 3-carboxy-1-(4′-nitrophenacyl)-5-bromopyridinium bromide (12), were highly active against Gram-positive and Gram-negative bacteria among all the tested compounds. All the compounds were examined for antifungal activity against fifteen fungal cultures, but none of these compounds proved to be effective against these fungi. The parent compounds and its derivatives were also examined for their effect on mean arterial blood pressure in anaesthetized rats. Compounds 7 and 8 were found to be twofold more active than the parent compound. The rest of the products showed blood pressure lowering effects comparable to the parent compound. All compounds were characterised via elemental analysis UV, IR , mass and 1H NMR spectroscopy.

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40

Fukushi, Keiichi, and Kazuo Hiiro. "Simultaneous determination of bromide and iodide ions by capillary isotachophoresis using quaternary ammonium salts." Journal of Chromatography A 760, no. 2 (January 1997): 253–58. http://dx.doi.org/10.1016/s0021-9673(96)00629-2.

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41

Vivek, J. P., and Ian J. Burgess. "Quaternary Ammonium Bromide Surfactant Adsorption on Low-Index Surfaces of Gold. 1. Au(111)." Langmuir 28, no. 11 (March 9, 2012): 5031–39. http://dx.doi.org/10.1021/la300035n.

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42

Loubinoux, Bernard, and Hassan Malek. "Interactions of Quaternary Ammonium Salts with Wood - 1. Fixation of Benzalkonium Bromide and Chloride." Holzforschung 46, no. 6 (January 1992): 537–39. http://dx.doi.org/10.1515/hfsg.1992.46.6.537.

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43

Xiao, Hui, and Rui Hai Li. "Study on Synthesis of a Ampholytic Polyphenylene Sulfide (PPS)." Advanced Materials Research 550-553 (July 2012): 757–61. http://dx.doi.org/10.4028/www.scientific.net/amr.550-553.757.

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Ampholytic Polyphenylene Sulfide (PPS) was prepared from PPS by sulfonation, followed by bromination and then the substitution of bromine by quaternary ammonium group and tertiary amine group.The structure and properties of polymers were characterized by FT-IR, TGA, UV and isoelectric point(IEP) measurement. The degree of sulfonation and the content of bromide were investigated by acid base titration and Mohr Method respectively. The results indicated that 47.6% sulfonation degree at 4h, 105°C and a 15ml/g ratio of oluem and PPS, 35.25% content of bromide at 4h, 40°C and 4% FeCl3. Bromine is completely substituted by quaternary ammonium groups at a 1:1.2 ratio of P-SO3-Br and volume of trimethylamine,70°C and 4 h,and that by tertiary amine groups at a 1:1.2 ratio of P-SO3-Br and volume of dimethylamine,80°C and 4 h. Ampholytic PPS shows better solubility and thermostability than PPS.Hyperchromic effect: Br < NH(CH3)2 < N(CH3)3. The IEP of P-SO3-TMA and P-SO3-DMA are 4.08 and 3.84 respectively.

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44

Różycka-Roszak, Bożenna, Romuald Żyłka, Teresa Kral, and Adriana Przyczyna. "Counterion Effects on Interaction of Amphiphilic Quaternary Ammonium Salts with Model Membranes." Zeitschrift für Naturforschung C 56, no. 5-6 (June 1, 2001): 407–12. http://dx.doi.org/10.1515/znc-2001-5-614.

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The micellization as well as the interaction with model membranes of dodecyltrimethylammonium halides (DTAX) and N-dodecyl-N,N-dimethyl-N-benzylammonium halides (DBeAX) were studied at 298K and 313K by means of titration calorimetry. The calorimetric curves reflect both the counterion and benzyl group effects on the interaction of the surfactants studied with the lipid bilayer. Bromide as counterion enhanced the interactions more than chloride of both DTAX and DBeAX compounds with model membranes. Further, we studied the influence of DTAX and DBeAX on calcium ion desorption from the liposome membrane using a radioactive tracer method. DBeAX proved more efficient in desorption of calcium than DTAX. Iodides of these compounds enhanced this process more than bromides and chlorides.

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45

Bora, Upasana, Mihir K. Chaudhuri, Deepa Dey, and Siddhartha S. Dhar. "Peroxometal-mediated environmentally favorable route to brominating agents and protocols for bromination of organics." Pure and Applied Chemistry 73, no. 1 (January 1, 2001): 93–102. http://dx.doi.org/10.1351/pac200173010093.

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Higher-valent transition metals react with H2O2 to form peroxometallates, thereby activating the coordinated peroxide. Based on the reaction profiles of peroxometal species, environmentally acceptable newer syntheses of tetrabutylammonium tribromide (TBATB), Bu4NBr3, cetyltrimethylammonium tribromide (CTMATB), cetyl(Me)3NBr3, and tetraethyl-ammonium tribromide (TEATB), Et4NBr3, have been developed from the reactions of the corresponding quaternary ammonium bromides with H2O2 and a catalytic amount of vanadium(V) or molybdenum(VI). Other transition metals capable of activating peroxide give similar results. The quaternary ammonium tribromides (QATBs) thus produced, especially TBATB and CTMATB, very efficiently act as clean and selective brominating agents for a variety of organic substrates. Very facile bromination of organic substrates, including aromatics, is also possible by tetrabutylammonium bromide (TBAB) Bu4NBr, either promoted by V2O5H2O 2 or catalyzed by MoO42H2 O2. The scope of the protocols has been underscored, and the relevance to green chemistry has been highlighted.

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46

Lewandowski, Grzegorz. "Efficiency of selected phase transfer catalysts for the synthesis of 1,2-epoxy-5,9-cyclododecadiene in the presence of H2O2/H3PW12O40 as catalytic system." Polish Journal of Chemical Technology 15, no. 3 (September 1, 2013): 96–99. http://dx.doi.org/10.2478/pjct-2013-0053.

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Abstract The results of the studies on the influence of the phase transfer catalyst on the epoxidation of (Z,E,E)-1,5,9-cyclododecatriene (CDT) to 1,2-epoxy-5,9-cyclododecadiene (ECDD) in the H2O2/H3PW12O40 system by a method of phase transfer catalysis (PTC) were presented. The following quaternary ammonium salts were used as phase transfer catalysts: methyltributylammonium chloride, (cetyl)pyridinium bromide, methyltrioctylammonium chloride, (cetyl)pyridinium chloride, dimethyl[dioctadecyl(76%)+dihexadecyl(24%)] ammonium chloride, tetrabutylammonium hydrogensulfate, didodecyldimethylammonium bromide and methyltrioctylammonium bromide. Their catalytic activity was evaluated on the basis of the degree of CDT and hydrogen peroxide conversion and the selectivities of transformation to ECDD in relation to consumed CDT and hydrogen peroxide. The most effective PT catalysts were selected based on the obtained results. Among the onium salts under study, the epoxidation of CDT with hydrogen peroxide proceeds the most effectively in the presence of methyltrioctylammonium chloride (Aliquat® 336) and (cetyl)pyridinium chloride (CPC). The relatively good results of CDT epoxidation were also achieved in the presence of Arquad® 2HT and (cetyl)pyridinium bromide

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47

Hussain, Zakir, Deepa Meghavathu, and Rakesh Kumar. "Effect of Quaternary Ammonium Salt Addition to Conventional Biodiesel Production Process." International Journal of Engineering & Technology 7, no. 4.5 (September 22, 2018): 220. http://dx.doi.org/10.14419/ijet.v7i4.5.20050.

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Biodiesel on a commercial scale is largely produced by transesterification using a conventional homogeneous catalyst like KOH and NaOH. The major problem associated with conventional homogeneous transesterification process is that it is prone to water & FFA content. This problem can be mitigated with some process modification using quaternary ammonium salts. In the present study, the reaction between waste palm oil & methanol was carried in a batch reactor at 65oC & various molar ratios of oil to methanol. Further, the effect of various dosages of tetramethylammonium bromide (TMAB) addition to this reaction was studied. Results show that there is a strong influence of TMAB (a phase transfer catalyst) on the methanol requirement during the reaction and also on the washability characteristics of the produced biodiesel. It was observed that there is a considerable decrease in the molar ratio of methanol to oil requirement during the reaction. Moreover, the addition of TMAB has enhanced the washability of the final biodiesel product by forming less foam. This has a direct advantage of decreasing the water requirement during the purification process.

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48

Lu, Feng-Ling, Ming-Xia Shen, Yi-Jiao Xue, Shao-Hua Zeng, Shang-Neng Chen, Ling-Yun Hao, and Lu Yang. "Application of calcium montmorillonite on flame resistance, thermal stability and interfacial adhesion in polystyrene nanocomposites." e-Polymers 19, no. 1 (May 29, 2019): 92–102. http://dx.doi.org/10.1515/epoly-2019-0012.

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AbstractTo exploit the application of calcium montmorillonite (CaMt) and improve the flame resistance of polystyrene (PS), two kinds of long carbon chain quaternary ammonium bromides with different spatial effect (i.e., cetyltrimethyl ammonium bromide (CTAB) and didodecyl dimethyl ammonium bromide (DDAB)) were used to intercalate CaMt for yielding corresponding organic calcium montmorillonite (CaOMt). The PS nanocomposites containing CaOMt (PS/CaOMt) were prepared by melt blending method. The effects of CaOMt on flame resistance, thermal stability, tensile properties and interfacial adhesion of PS/CaOMt were investigated. The results showed that both CTAB and DDAB were intercalated into CaMt to get CaOMt with an exfoliated/intercalated structure, which could endue good interfacial adhesion and thermal stability for PS/CaOMt. All peak values of flame resistance parameters of PS/CaOMt decreased and corresponding combustion times were postponed obviously. Moreover, Young’s modulus of DDAB-intercalated PS/CaOMt was improved by 49.1% while its tensile strength kept at the same level as PS.

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49

Thomas, Trisha J., Karthik E. Ponnusamy, Nancy M. Chang, Kim Galmore, and Shelley D. Minteer. "Effects of annealing on mixture-cast membranes of Nafion® and quaternary ammonium bromide salts." Journal of Membrane Science 213, no. 1-2 (March 2003): 55–66. http://dx.doi.org/10.1016/s0376-7388(02)00512-4.

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50

Bales, Barney L., and Raoul Zana. "Characterization of Micelles of Quaternary Ammonium Surfactants as Reaction Media I: Dodeclytrimethylammonium Bromide and Chloride." Journal of Physical Chemistry B 106, no. 8 (February 2002): 1926–39. http://dx.doi.org/10.1021/jp013813y.

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