- Synthesis, Characterization, and Surface Activities of Polymeric Cationic Thiol Surfactants in Aqueous Medium
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A series of cationic polyurethane surfactants [PQ8-18] were synthesized by the reaction of alkyl bromoacetate (namely: octyl-, decyl-, dodecyl-, tetradecyl-, hexadecyl-, and octadecyl bromoacetate) as quaternizing agents and modified polyurethane contains tertiary amine species. Modified polyurethane was prepared by the reaction of toluene diisocyanate (TDI) and triethanol amine monomercaptoacetate. The chemical structures of the prepared surfactants were confirmed using elemental analysis, Fourier transform infrared spectroscopy (FTIR), and Proton nuclear magnetic resonance (1H NMR) spectroscopy. The molecular weight measurements of the prepared polymers showed that the segments of each polymer contain average 10 units of the urethane-triethanol amine mercaptoacetate. The surface activities of the prepared surfactants including: surface tension (γ), effectiveness (πcmc), concentration at micelle formation (CMC), efficiency (Pc20), maximum concentration at the interface (Γmax), and the average area occupied by each surfactant molecule at the interface at equilibrium (Amin) of surfactants solutions were established at 25°C. The surface tension and the critical micelle concentration values of the prepared surfactants were gradually decreased by the gradual increase of their alkyl chain length. The prepared cationic surfactants showed efficient activity as inhibitors for dissolution of carbon steel in an acidic medium and also as a biocide against the growth of bacteria, fungi, and yeast.
- Zaky, Mohamed F.,Sabbah, Ibrahim A.,Hendawy, Mostafa E.,Abdel Hameed, Reda S.,Negm, Nabel A.
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- Surface and thermodynamic studies of N-((octyl, dodecyl, and cetyl) oxycarbonylmethyl) pyridinium bromide
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N-Octyloxycarbonylmethyl pyridinium bromide (C8), N-dodecyloxycarbonylmethyl pyridinium bromide (C12) and N-cetyloxycarbonylmethyl pyridinium bromide (C16) were prepared. Several studies were carried out with their aqueous solutions. Surface tensions, electrical conductivities, and biodegradabilities were evaluated. The antibacterial and antifungal activities of the cationic surfactants were studied. Surface properties, particularly critical micelle concentration (CMC), effectiveness (ΠCMC), efficiency (Pc20), maximum surface excess (Γmax), and minimum surface area (Amin) were investigated at different concentrations at 20, 35, and 50°C respectively. Free energies, enthalpies, entropies of micellization, and adsorption of the surfactants in the aqueous solution were studied.
- Gad,El-Sukkary,Azzam
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- Structure and biological behaviors of some metallo cationic surfactants
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In this study, different cationic surfactants were prepared by esterification with bromoacetic acid of different fatty alcohols, i.e., dodecyl, tetradecyl and hexadecyl species. The products were then reacted with diphenyl amine, and the resulting tertiary amines were quaternized with benzyl chloride to produce a series of quaternary ammonium salts. The metallocationic surfactants were prepared by complexing the cationic surfactants with nickel and copper chlorides. Surface tension of these surfactants were investigated at different temperatures. The surface parameters including critical micelle concentration (CMC), maximum surface excess (Γ max), minimum surface area (A min), efficiency (PC20) and effectiveness (π CMC) were studied. The thermodynamic parameters such as the free energy of micellization (δ Gmic°) and adsorption (δ Gads°), enthalpy (δ H m°), (δ Hads°) and entropy (δ Sm), (δ Sads°) were calculated. FTIR spectra and 1H-NMR spectra were obtained to confirm the compound structures and purity. In addition, the antimicrobial activities were determined via the inhibition zone diameter of the prepared compounds, which were measured against six strains of a representative group of microorganisms. The results indicate that these metallocationic surfactants exhibit good surface properties and good biological activity on a broad spectrum of microorganisms.
- Adawy, Ahmed I.,Khowdiary, Mnal M.
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- Screening for potential antimicrobial activities of some cationic uracil biocides against wide-spreading bacterial strains
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Eight novel uracil-based cationic surfactants containing Schiff base species were synthesized and characterized using elemental analysis, FTIR, 1H-NMR and 13C-NMR spectroscopy. The surface activities of the synthesized Schiff bases and their cationic derivatives were determined based on interfacial tension measurements and partition coefficient values in water/octanol system. The synthesized Schiff bases and their cationic derivatives were evaluated as novel biocides against different bacteria and fungi strains. The results showed that the biocidal activity of the synthesized Schiff bases was considerably increased by quaternization. The influence of the cationic surfactants as biocides was increased by increasing the hydrophobic chain length and the presence of the methoxy groups. The biocidal activity was also increased by increasing the partition coefficient inwater/octanol system.The structure and surface activity/ biocidal activity of the different compounds were discussed. AOCS 2010.
- Negm, Nabel A.,Aiad, Ismail A.,Tawfik, Salah M.
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- Synthesis and in vitro transdermal penetration enhancing activity of lactam N-acetic acid esters
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A homologous series of N-acetic acid esters of 2-pyrrolidinone and 2- piperidinone has been prepared and evaluated for its ability to enhance the skin content and flux of hydrocortisone 21-acetate in hairless mouse skin in vitro. Enhancement ratios (ER) were determined for flux (J), 24-hour diffusion cell receptor cell concentrations (Q24), and 24-h full-thickness mouse skin steroid content (SC) and compared to control values (no enhancer present). In addition, in an attempt to abrogate toxicity, these dermal penetration enhancers were designed to have the potential for biodegradation by dermal esterases. 2-Oxopyrrolidine-α-acetic acid dodecyl ester (5) showed the highest enhancement ratios for J (ER 67.33) and Q24 (ER 180.66). 2- Oxopiperidine-α-acetic acid decyl ester (10) showed a high Q24 (ER 162.07) but a lower J (ER 12.67). 2-Oxopyrrolidine-α-acetic acid decyl ester (3) showed the highest enhancement ratio for SC (ER 8.7). The ER Q24 for 3, 5 and 10, as well as other lactam N-acetic acid esters in this work, were significantly higher than the ER found using Azone as enhancer.
- Michniak, Bozena B.,Player, Mark R.,Sowell Sr., J. Walter
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- Synthesis of ester based cationic pyridinium gemini surfactants and appraisal of their surface active properties
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New pyridinium gemini surfactants have been synthesized by esterification of halogenated carboxylic acids with long chain fatty alcohols furnishing respective esters (dodecyl-2-chloroacetate, tetradecyl-2-chloroacetate, hexadecyl-2-chloroacetate, dodecyl-2-bromoacetate, tetradecyl-2-bromoacetate and hexadecyl-2-bromoacetate) followed by their subsequent treatment with 4,4′-trimethylene dipyridine resulting in the formation of title Gemini surfactants: 4,4′-(propane-1,3-diyl)bis1-{2-(dodecyloxy)-2-oxoethyl}; 4,4′-(propane-1,3-diyl)bis{1-(2-(tetradecyloxy)-2-oxoethyl}; 4,4′-(propane-1,3-diyl)bis{1-(2-(hexadecyloxy)-2-oxoethyl} dipyridinium chlorides; 4,4′-(propane-1,3-diyl)bis{1-(2-(dodecyloxy)-2-oxoethyl}; 4,4′-(propane-1,3-diyl)bis{1-(2-(tetradecyloxy)-2-oxoethyl} and 4,4′-(propane-1,3-diyl)bis{1-(2-(hexadecyloxy)-2-oxoethyl} dipyridinium bromides. Their identifications are based on IR, 1H-NMR, 13C-NMR, DEPT, COSY and Mass spectral studies. Their surface active properties were also evaluated on the basis of surface tension and conductivity measurements.
- Patial, Pankaj,Shaheen, Arifa,Ahmad, Ishtiaque
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- Betaine ester-shell functionalized hyperbranched polymers for potential antimicrobial usage: Guest loading capability, pH controlled release and adjustable compatibility
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Betaine ester-shell functionalized hyperbranched polyethylenimines (BEHPEI) were synthesized by Menschutkin reaction between per-N-methylated polyethylenimine (MeHPEI) and alkyl bromoacetate. BEHPEI could play dual antimicrobial roles that were, the betaine ester-shell acted as contact-based antibacterial polycations and the drug-loaded BEHPEI could controllably release the drugs due to the cleavage of the betaine ester groups under weak alkaline condition. The BEHPEI exhibited high transport capacities that per gram of BEHPEI could encapsulate 0.24-2.67 g of dyes or drugs. The model drug release experiment employing methyl orange (MO) showed that the drug release of MO-loaded BEHPEI complex occurred slowly in weak alkaline solutions and the release rate was controlled by varying pH, while the complex kept very stable under weak acid condition (pH = 3.0-7.0). BEHPEI generated from long chain alkyl bromoacetate was compatible with organic resins implying the possible usage in antimicrobial fibers and coatings. Another BEHPEI obtained from short-chain alkyl bromoacetate was water soluble and maybe used in lotion formula. The hydrolysis of BEHPEI afforded zwitterionic shell.
- Zhou, Xin,Chen, Yongyue,Han, Jin,Wu, Xuedong,Wang, Gang,Jiang, Daoyi
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- Surface charge-convertible quaternary ammonium salt-based micelles for in vivo infection therapy
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Quaternary ammonium salts (QASs) are excellent candidates for treating stubborn bacterial infections caused by biofilms due to their high sterilization efficiency and potential inhibition of the development of drug resistance. However, the inherent toxicity of QASs, including cytotoxicity, protein absorption and hemolysis, severely limits their applications in vivo. Herein, a charge-convertible quaternary ammonium salt-based micelle (QAS-SL@CM) was constructed by co-assembly of two amphiphiles with opposite charges and shell cross-linking strategy. The toxicity of the QAS-SL@CM could be greatly reduced towards human cells contrast to the corresponding QASs. By response to the acidic environment at infection sites, the surface charge of QAS-SL@CM could be immediately changed to positive and then target to negatively charged bacteria. Furthermore, β-thiopropionate bonds on QAS-SL@CM could also be disintegrated under acid environment to release QASs to kill bacteria. Importantly, the QAS-SL@CM showed significant therapeutic effect in mice subcutaneous abscesses models without interference with normal cells. Therefore, a surface adaptive micelle constructed by charge-convertible strategy has been developed to overcome the cytotoxicity of QASs, and could intelligently respond to the microenvironment of infected wound for in vivo infection therapy, which shows promising application in clinic.
- He, Dengfeng,Tan, Yifeng,Li, Pengfei,Luo, Yadong,Zhu, Yuhong,Yu, Yunlong,Chen, Jiali,Ning, Ning,Zhang, Shiyong
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- ARYLAZO-HETEROARYL COMPOUNDS AND THEIR USE FOR LONG-TERM THERMAL ENERGY STORAGE
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The present invention relates to a compound of Formula (I): wherein R1, R2, m, n, p, Q, X, Y, W, and "A" are as described herein. The present invention also relates to a process for preparation of a compound of Formula (I). Also disclosed is a thermal-storage device comprising one or more compounds of Formula (I) and a method of storing energy.
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Paragraph 0140-0142
(2021/08/13)
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- Preparation method of tetra-ester gemini quaternary ammonium salt leather sterilization mildew inhibitor
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The invention discloses a preparation method of a tetra-ester gemini quaternary ammonium salt leather sterilization mildew inhibitor. The preparation method comprises the following steps: firstly, taking hydroxyl-terminated diol and chloroacetyl chloride as reactants, and synthesizing ester dichloride through nucleophilic substitution reaction; then carrying out nucleophilic substitution reaction on the ester group dichloride and diethylamine to synthesize ester group di-tert-amine; then using fatty alcohol and bromoacetyl bromide as reactants to synthesize bromoacetate through acylation reaction; and finally, carrying out quaternization reaction on the obtained bromoacetate and ester group di-tert-amine to obtain the tetra-ester gemini quaternary ammonium salt bactericidal mildew inhibitor, and respectively distributing ester groups on a spacer group and a hydrophobic chain of the gemini quaternary ammonium salt. The tetra-ester gemini quaternary ammonium salt leather sterilization mildew inhibitor prepared by the method has good antibacterial and mildew-proof performance, can be applied to the sterilization and mildew-proof field of leather, and has a good market application prospect.
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Paragraph 0016; 0029
(2021/07/31)
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- Arylazopyrazoles for Long-Term Thermal Energy Storage and Optically Triggered Heat Release below 0 °c
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Arylazopyrazole derivatives based on four core structures (4pzMe, 3pzH, 4pzH, and 4pzH-F2) and functionalized with a dodecanoate group were demonstrated to store thermal energy in their metastable Z isomer liquid phase and release the energy by optically triggered crystallization at -30 °C for the first time. Three heat storage-release schemes were discovered involving different activation methods (optical, thermal, or combined) for generating liquid-state Z isomers capable of storing thermal energy. Visible light irradiation induced the selective crystallization of the liquid phase via Z-to-E isomerization, and the latent heat stored in the liquid Z isomers was preserved for longer than 2 weeks unless optically triggered. Up to 92 kJ/mol of thermal energy was stored in the compounds, demonstrating remarkable thermal stability of Z isomers at high temperatures and liquid-phase stability at temperatures below 0 °C.
- Gerkman, Mihael A.,Gibson, Rosina S. L.,Calbo, Joaquín,Shi, Yuran,Fuchter, Matthew J.,Han, Grace G. D.
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supporting information
p. 8688 - 8695
(2020/12/23)
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- Synthesis of novel oil-soluble fluorinated surfactants via Wittig-Horner reaction
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In this paper, the synthesis and characterization of novel oil-soluble fluorinated surfactants were reported. Both Wittig and Wittig-Horner reaction were used for constructing the perfluorinated branch-chain structure, and the latter provided a better method through a three-step synthesis route which was easy worked up and low cost. The surface tension of novel products in toluene, n-hexane and nitromethane with concentrations of 0.1 mol/L, 0.05 mol/L, 0.025 mol/L, 0.0125 mol/L, 0.00625 mol/L and 0 mol/L were examined. The surface tension research of these surfactants showed that they can reduce the surface tension of organic reagents dramatically. For example, compound 1e can reduce the surface tension of nitromethane from 36.6 mN/m to 24.2 mN/m in the concentration of 0.1 mol/L, and the surface tension of toluene was reduced from 28.0 mN/m to 22.7 mN/m when the concentration of compound 1a was 0.1 mol/L.
- Zhang, Ding,Sha, Min,Xing, Ping,Pan, Renming,Lin, Xiangyang,Jiang, Biao
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p. 1652 - 1657
(2019/02/06)
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- Biocidal activity and corrosion inhibition of some cationic surfactants derived from thiol polyurethane
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S IX series of cationic polyurethane surfactants [PQ10-20] were synthesized by the reaction between different six esters (which prepared by condensation of fatty alcohols namely: octanol, decanol, dodecanol, tetradecanol, hexadecanol and octadecanol with bromoacetic acid) and polyurethane as quaternizing agent. The chemical structures of these surfactants were confirmed using elemental analysis, FTIR spectra,+HNMR and UV analysis. The surface activities of the synthesized cationic thiol polyurethane surfactants showed their tendency towards adsorption at the air/water interface. The adsorption tendency was estimated from the values of surface tension and the depression of surface tension at the critical micelle concentration. The studied surfactants were evaluated as antimicrobial agents against pathogenic and sulfur reducing bacteria using inhibition zone diameters and minimum inhibition concentration values. The synthesized cationic thiol polyurethane surfactants showed good antimicrobial activities against the tested microorganisms including Gram positive, Gram negative as well as fungi. The synthesized compounds were tested for the activity as corrosion inhibitors against carbon steel corrosion in 2N H2SO4 at 50, 100, 200, 400 and 600 ppm. The inhibition efficiencies of the tested compounds showed good inhibition and protection of the carbon steel. The corrosion inhibition tendency correlated to the surface activity and chemical structure of the compounds.
- Zaky, Mohamed F.,Sabbah,Negm,Hendawy
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- A reactive Gemini quaternary ammonium salt leather method for producing the same (by machine translation)
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The invention discloses a reactive Gemini quaternary ammonium salt leather method for producing the same, comprises three steps: 1st step is [...] and fatty alcohol esterification reaction generating [...] ester, 2nd step is anti-- 1, 4 - dichloro - 2 - butene and diethylamine the nucleophilic substitution reaction to produce trans - N, N, N', N' - four ethyl - 2 - butene - 1, 4 - diamine, the first two steps of 3rd step is obtained by reaction of the product of the quaternized reactive Gemini quaternary ammonium salt. The preparation process is easy to operate, high yield, low cost of raw materials, and the practicability is strong, and the 2nd step in the synthesis of diamine, as the Gemini quaternary ammonium salt for synthesizing new ideas and new method. The invention preparation of the molecular structure of the presence of the fungicide ester not only can enhance the sterilizing performance, and can be given to its good biodegradability. In addition, the structure of the active group in the presence of C=C, increases the chemical activity of the quaternary ammonium salt surfactant, make it can be further chemically bonded and the leather skin collagen in resin material, can be given to its permanent sterilization performance. (by machine translation)
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Paragraph 0020
(2018/04/15)
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- Template-Assisted Benzannulation Route to Pentacene and Tetracene Derivatives and its Application to Construct Amphiphilic Acenes That Self-Assemble into Helical Wires
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Pentacene is one of the most versatile organic semiconductors. New synthetic strategies to construct the pentacene skeleton are imperative to produce pentacene derivatives with appropriate solubility, stability, and optoelectronic properties for various applications. This paper describes a template-directed approach to pentacene derivatives. In the retrosynthesis, the acene skeleton is viewed as a laddered double strand polyene instead of the more intuitive linearly fused hexagons. Based on this vision, the template strand of polyene is constructed with Wittig olefination, whereas the second strand is accomplished with Knoevenagel condensation to produce pentacene and tetracene derivatives. The synthetic scheme is flexible enough to generate an array of acene derivatives with substitution patterns that were hitherto difficult to access. Amphiphilic pentacene and tetracene derivatives were also synthesized by the template strategy. One pentacene based amphiphilic rod-coil molecule undergoes self-assembly to form helical wire structures that were visualized with TEM.
- Pal, Bikash,Chang, Chun-Hsiung,Zeng, Cian-Jhe,Lin, Chih-Hsiu
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supporting information
p. 17542 - 17548
(2017/11/22)
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- Phase Transfer Catalysis with Quaternary Ammonium Type Gemini Surfactants: O-Alkylation of Isovanillin
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In this paper, O-alkylation of isovanillin with unusual phase transfer catalysts alkandiyl-α,ω-bis(dimethylalkylammonium bromide) dimeric surfactants (also known as gemini surfactants) is described. Some dimeric surfactants with simple hydrophobic alkyl chains and others with hydrophobic alkyl chains containing ester functionalities with different lengths were synthesized and characterized in our laboratory. The alkylation of isovanillin with alkyl halide was successively carried out in the presence of potassium carbonate and a phase transfer catalyst in tetrahydrofuran. The same reactions were also performed with both the traditional phase transfer catalyst tetrabutylammonium bromide and without any catalyst. The results were compared with those of dimeric surfactants. Consequently, it was expressed that alkandiyl-α,ω-bis(dimethylalkylammonium bromide) dimeric surfactants successively exhibit the character of phase transfer catalysts through environmentally friendly procedures under mild conditions. The most significant feature of this work is that dimeric surfactants have been determined to act as phase transfer agents.
- Boz, Mesut,Ba?türk, Sedat Semih
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p. 663 - 671
(2016/07/06)
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- Visible-light-promoted conversion of alkyl benzyl ether to alkyl ester or alcohol via O-α-sp3 C-H cleavage
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A mild and high-yielding visible-light-promoted conversion of alkyl benzyl ethers to the alkyl esters or alkyl alcohols was developed. Mechanistic studies provided evidence for a radical chain reaction involving the homolytic cleavage of O-α-sp3 C-H bonds in the substrate as one of the propagation steps. We propose that α-bromoethers are key intermediates in the transformation.
- Lu, Ping,Hou, Tianyuan,Gu, Xiangyong,Li, Pixu
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p. 1954 - 1957
(2015/04/27)
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- KETOCOUMARINS AS PHOTOINITIATORS AND PHOTOSENSITIZERS IN INKS
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A series of novel ketocoumarin photoinitiators are disclosed for use in radiation curing.
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Page/Page column 25
(2014/02/16)
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- Novel cationic schiff base surfactants: Surface studies and biocidal activities against bacteria fungi and sulfate reducing bacteria
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Novel series of cationic Schiff base surfactants were synthesized and characterized using microelemental analysis, FTIR and 1H-NMR spectra. The properties of the synthesized surfactant solutions such as critical micelle concentration (CMC), effectiveness (πCMC), surface excess concentration (Γmax), surface area (Amin) and free energy of micellization (δGmic) were determined using surface tension measurements. These Schiff base surfactants were evaluated for their antibacterial activity against Gram positive and Gram negative bacteria and fungi. The results of the biocidal activities revealed high potent action of the Schiff bases towards bacteria and fungi. The biocidal activity of the tested compounds against sulfur (sulfate) reducing bacteria (SRB) showed promising results in the area of oil field applications.
- Zaky,Badawi,Ead,Aboulimoud
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p. 201 - 211
(2014/04/03)
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- Synthesis, characterization and surface activity of new eco-friendly schiff bases vanillin derived cationic surfactants
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Three eco-friendly cationic surface active agents were synthesized from the chemical modification of vanillin. The chemical structures of these surfactants were confirmed using elemental analysis, IR and NMR spectra. The surface activity measurements showed their high tendency towards adsorption and micellization and their good surface tension reduction, low interfacial tension. The emulsion stability measurements showed acceptable efficiency as emulsifying agents for short term emulsions. The biodegradability tests revealed that these compounds are eco-friendly and had completely degraded in 30 days. AOCS 2011.
- Negm, Nabel A.,Kandile, Nadia G.,Mohamad, Mohamad A.
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experimental part
p. 325 - 331
(2012/07/14)
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- An improved greener esterification of fatty alcohols using a renewable acid-ionic liquid couple as catalyst-solvent
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We have developed a simple and efficient method for the esterification of various organic acids with C4-C18 alcohols using the 1-octyl-3-methyl- imidazolium tetrafluoroborate-para-toluenesulphonic acid (OMIM/BF 4-PTSA) couple, without organic solvent, either by classic heating or by microwave irradiation. The utilisation of the OMIM/BF4-PTSA couple presents considerable advantages: high yield, low temperature, short reaction time, isolation of the ester by simple decantation, easy reuse of the catalyst couple.
- Nguyen, Hoang-Phuong,Znifeche, Samira,Baboulene, Michel
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p. 2085 - 2093
(2007/10/03)
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- Influence of structure on the cationic polytriethanolammonium bromide derivatives. I. Synthesis, surface and thermodynamic properties
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A NOVEL class of cationic polytriethanolamine derivatives was prepared. Di, tri- and tetratriethanolamine were prepared. Then, quatemization process was carried out by the reaction of polytriethanolamine and different haloesters of a fatty alcohol in acetone. Chemical structure was confirmed via IR and elemental microanalysis. Surface properties of the prepared compounds including critical micelle concentration (CMC), effectiveness (πcmc), maximum surface excess (Γmax) and minimum surface area (Amin) were determined at 30, 40 and 50°C. The obtained results showed good surface properties for the prepared compounds either in the adsorption state or in the bulk of their solutions.
- Negm,Hafiz,El Awady
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p. 369 - 381
(2007/10/03)
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- Surface and Thermodynamic Properties of Octyl, Dodecyl, and Cetyl Sulfoacetates
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Three anionic surfactants (Na-octysulfoacetate (A8), Na-dodecylsulfoacetate (A12), and Na-cetylsulfoacetate (A16) were prepared from alkyl bromoacetate. Several studies were carried out with aqueous surfactant solutions including surface tension, and electrical conductivity measurements. Surface properties, in particular, critical micelle concentration (CMC), effectiveness (ΠCMC), efficiency (Pc20), maximum surface excess (Γmax), and minimum surface area (Amin) were investigated at different concentrations at 20, 35 and 50°C, respectively. Free energies, enthalpies, entropies of micellization, and adsorption of the surfactants in the aqueous solution were studied.
- Gad,El-Sukkary,Azzam
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p. 1085 - 1092
(2007/10/03)
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- Process for the preparation of bromoacetic acid and esters thereof
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New economically valuable and convenient methods for preparing bromoacetic acid and its esters from chloroacetic acid are disclosed.
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