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1.
联接基对双子表面活性剂12-s-12表面活性的影响   总被引:6,自引:0,他引:6  
双子表面活性剂是通过一个联接基将两个传统表面活性剂分子在其亲水头基或接近亲水头基处联接在一起而形成的 类新型表面活性剂,属于低聚表面活性剂范畴[1-3],通常表示为m-s-m·2X,其中m表示两个疏水尾基的碳原子数,s表示联接基中亚甲基,X代表反离子.  相似文献   

2.
The micellization processes of N-dodecyl-N,N-dimethyl-N-[3-(β-methyl-β-nitrovinyl)-6-methoxybenzyl] ammonium chloride (I-A), N-dodecyl-N,N-dimethyl-N-benzylammonium chloride (I-B), N-dodecyl-N, N,N-trimethylammonium chloride (I-C), N-dodecyl-[3-(β-methyl-β-nitrovinyl)-4-methoxybenzyl] morpholinium chloride (IV-A), N-dodecyl-N-benzylmorpholinium chloride (IV-B), N-dodecyl-N-methylmorpholinium chloride (IV-C), and N-dodecyl-N-methylpiperidinium chloride (VI-C) were studied by means of the calorimetric titration method. The critical micelle concentrations and enthalpies of micellization were determined. It is suggested that the benzyl groups of I-B and IV-B and the nitrovinylbenzyl groups of I-A and IV-A behave as second chains during the micellization.  相似文献   

3.
New water‐soluble methacrylate polymers with pendant quaternary ammonium (QA) groups were synthesized and used as antibacterial materials. The polymers with pendant QA groups were obtained by the reaction of the alkyl halide groups of a previously synthesized functional methacrylate homopolymer with various tertiary alkyl amines containing 12‐, 14‐, or 16‐carbon alkyl chains. The structures of the functional polymer and the polymers with QA groups were confirmed with Fourier transform infrared and 1H and 13C NMR. The degree of conversion of alkyl halides to QA sites in each polymer was determined by 1H NMR to be over 90% in all cases. The number‐average molecular weight and polydispersity of the functional polymer were determined by size exclusion chromatography to be 32,500 g/mol and 2.25, respectively. All polymers were thermally stable up to 180 °C according to thermogravimetric analysis. The antibacterial activities of the polymers with pendant QA groups against Staphylococcus aureus and Escherichia coli were determined with broth‐dilution and spread‐plate methods. All the polymers showed excellent antibacterial activities in the range of 32–256 μg/mL. The antibacterial activity against S. aureus increased with an increase in the alkyl chain length for the ammonium groups, whereas the antibacterial activity against E. coli decreased with increasing alkyl chain length. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5965–5973, 2006  相似文献   

4.
5.
A series of long-chain quaternary ammonium hydroxides were synthesized from tertiary amines and confirmed by ~1H NMR and FTIR.Surface properties and pH of these surfactants were investigated.The critical micelle concentrations(CMC) of the synthesized quaternary ammonium hydroxides are lower than the conventional quaternary ammonium surfactants.The micelles shapes of these long-chain quaternary ammonium hydroxides in aqueous solution are spherical at a concentration of 0.1 mol/L.The pH values of the synthesized quaternary ammonium hydroxides are 12.25-12.51.  相似文献   

6.
陈寒松  李正名 《中国化学》2000,18(4):596-602
In order to search for novel fungicides with high activity, a series of heteroaryl pyrazoles were synthesized from 5-pyra-zole formhydrazide. The structures of all new compounds were confirmed by spectroscopic methods and microanalyses. Preliminary bioassays indicated that some compounds showed fungicidal activity against Puccinia tritinia and PGR activity as well.  相似文献   

7.
A series of novel quaternary ammonium surfactants containing adamantane were designed and synthesized from 1-adamantanecarboxylic acid.The structures of target surfactants were confirmed by]H NMR,elements analysis and FTIR.Surface properties of these surfactants were investigated.Due to the lipophilicity of adamantane,the critical micelle concentration(CMC) and C20 values of the synthesized quaternary ammonium surfactants are lower than that of conventional quaternary ammonium surfactants.  相似文献   

8.
From the dependence of the molal osmotic coefficients of (hept)4NX (X = Cl, Br, J), (hept)4NNO3 and (oct)4PNO3, in benzene at 33, 40 and 50°C, on the solute concentration, the dimerization constants of solute ion-pairs and the corresponding thermodynamic functions of dimerization, ΔG°, ΔH° and ΔS° have been calculated. The thermodynamic data are discussed in terms of a simple electrostatic model of association.  相似文献   

9.
The ammonia chemical ionization desorption spectra of N,N-dimethyl quaternary ammonium iodides in addition to high protonated molecular ion [M + H]+ intensity, show signals for an ion radical composed of N-methyl abstracted salt cation and ammonia [C + NH3? CH3]. These ions corresponding to the cation +2 show increased importance in the chemical ionization mode, using the same reagent gas. The technique of chemical ionization desorption appears suitable for the analysis of salts, and thus for the determination of the molecular weight of both anion and cation.  相似文献   

10.
Reaction of visnaginone which derived from the naturally occurring compound “visnagine”, with allyl bromide gave O‐allyl visnaginone 1 , which underwent Claisen rearrangement to yield 7‐allylbenzofuran 2 derivative. Vilsmeier Haack formylation of 2 afforded our versatile starting compound furochromene‐6‐carboxaldehyde ( 3 ) which was condensed with cyclohexane‐1,3‐dione, indandione, malononitrile or ethyl cyanoacetate to yield the ylidene nicotinonitrile and pyridone derivatives 4,7,10a‐b . Reaction of 3 with aniline or aniline acting on multiple function X‐H (X = NH, O, S) at its ortho position afforded the corresponding anils, imidazolylfurochromene and azepines compounds 11‐17 . On the other hand, oxidation of visnagin afforded chromene‐6‐carboxaldehyde derivative 18 which was condensed with different aryl or (heteroaryl) acetonitrile followed by hydrolysis to give pyrano[3,2‐g]chromen‐4,8‐dione derivatives 20a‐d and 22 .  相似文献   

11.
A series of fluorine-and piperazine-containing 1,2,4-triazole thione derivatives were synthesized by the Mannich reaction of triazole intermediates with various substituted piperazines and formaldehyde in high yields. Structures of title compounds were confirmed by melting points, IR, 1H NMR, 13C NMR and elemental analysis. The preliminary bioassays for 17 novel title compounds showed that several compounds have significant fungicidal activity against Cercospora arachidicola, Physalospora piricola and Rhizoctonia cerealis at 50μg/mL.  相似文献   

12.
Aromatic carboxylic acids on refluxing with 3,5,6-trichloro-2-pyridyloxyacetylhydrazide in POCl3 gave 5-aryl-2-(3,5,6-trichloro-2-pyridyloxymethyl)-1,3,4-oxadiazoles. The hydrazide on treatment with acid chlorides gave diacylhydrazines, whereas with arylsulfonyl chlorides acyl(arylsulfonyl)hydrazines were obtained. The latter two types of compounds were tested for their antibacterial and antifungal activities whereas 1,3,4-oxadiazole derivatives were tested for their herbicidal activity. Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 711–717, May, 2006.  相似文献   

13.
Two new polymerizable surfactants (surfmers), (11-acryloyloxyundecyl)dimethylethylammonium bromide (ethyl surfmer) and (11-acryloyloxyundecyl)dimethyl(2-hydroxyethyl)ammonium bromide (hydroxyethyl surfmer), were synthesized and characterized. The binary phase diagrams of both surfmer/water systems are described. Both surfmers can form isotropic solutions and lamellar lyotropic liquid crystalline phases. The hydroxyethyl surfmer/water system forms a lamellar phase for weight concentrations of surfmer between 70 and 90% relative to between 75 and 85% for the ethyl surfmer/water system. The differences in the self assembly of these surfmers were attributed to the ability of hydroxyethyl surfmer to form hydrogen bonds (between two head groups and with water), whereas no such interactions can occur with the ethyl surfmer system.  相似文献   

14.
New fluorine-containing quaternary ammonium salts exhibiting a high inhibiting capacity against hydrochloric acid corrosion of low-carbon steels were synthesized. The polarization resistance method was used to determine the uniform-corrosion rates of steel-3 and steel-35 in relation to the structure of fluorine-containing moieties of quaternary ammonium salts and their concentration.  相似文献   

15.
A star-shaped hexameric quaternary ammonium surfactant (PAHB), bearing six hydrophobic chains and six charged hydrophilic headgroups connected by an amide-type spacer group, was synthesized. The self-assembly behavior of the surfactant in aqueous solution was studied by surface tension, electrical conductivity, isothermal titration microcalorimetry, dynamic light scattering, cryogenic transmission electron microscopy, and NMR techniques. The results reveal that there are two critical aggregate concentrations during the process of aggregation, namely C(1) and C(2). The aggregate transitions are proved to be caused by the changes of the surfactant configuration through hydrophobic interaction among the hydrocarbon chains. Below C(1), PAHB may present a star-shaped molecular configuration due to intramolecular electrostatic repulsion among the charged headgroups, and large aggregates with network-like structure are observed. Between C(1) and C(2), the hydrophobic interaction among the hydrophobic chains may become stronger to make the hydrophobic chains of the PAHB molecules curve back and pack more closely, and then the network-like aggregates transfer to large spherical aggregates of ~100 nm. Beyond C(2), the hydrophobic interaction may become strong enough to cause the PAHB molecular configuration to turn into a pyramid-like shape, resulting in the transition of the spherical large aggregates to spherical micelles of ~10 nm. Interestingly, the PAHB displays high emulsification ability to linear fatty alkyls even at very low concentration.  相似文献   

16.
A general method for the synthesis of quaternary ammonium cations in acidic zeolites by a direct reaction of tertiary amines and alcohols is described.  相似文献   

17.
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   

18.
用柠檬酸、十二烷基二甲基叔胺与环氧氯丙烷反应合成了柠檬酸三酯三烷基季铵盐阳离子表面活性剂。实验结果表明,在异丙醇溶剂中,反应体系在80℃,反应时间12h,产物的收率为91.5%。用红外光谱、元素分析、高效液相色谱对其结构进行了表征,通过测定其临界胶束浓度、Krafft点及泡沫性能,对产物表面活性进行了分析。  相似文献   

19.
In this study, new alkaline exchange membranes were prepared from the perfluorinated 3M ionomer with various quaternary ammonium cations attached with sulfonamide linkage. The degree of functionalization varied depending on the cation species, resulting in different ion exchange capacities (IECs), 0.33–0.72 meq g−1. There was evidence of polymer degradation when the films were exposed to hydroxide, and hence all membrane characterization was performed in the chloride form. Conductivity was dependent on cation species and IEC, Ea = 36–59 kJ mol−1. Diffusion of water through the membrane was relatively high 1.6 × 10−5 cm2 s−1 and indicated restriction over a range of diffusion times, 6–700 ms. Water uptake (WU) in the membranes was generally low and the hydration level varied based on cation species, λ = 6–11. Small-angle scattering experiments suggested ionic aggregation, 37–42 Å, independent of cation species but slight differences in long-range order with cation species. © 2012 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013, 51, 1761–1769, 2013  相似文献   

20.
Quaternization of triethylamine, 4-dimethylaminopyridine, and N-methylimidazole with moraprenyl bromide gives the corresponding quaternary ammonium salts.  相似文献   

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