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1.
A series of new cationic surfactants, bis-quaternary ammonium salts and tris-ammonium salts, were prepared from N,N-dimethyldodecylamine and a product of the reaction of epichlorohydrin with ethyl-, propyl-, butyl-, pentyl-, hexyl-, and octylamine (in the xase of bis-ammonium salts) or the hydrochloride of diethyl-, dipropyl-, dibutyl-, or dihexylamine (in the case of tris-ammonium salts). The obtained multiple salts were examined with respect to their surface-active properties: Critical micelle concentrations (CMC), effectiveness of surface tension reductions (γCMC), and adsorption efficiencies (pC20) were measured. All these surfactants showed good water solubility and low CMC of more than one order of magnitude lower than those of corresponding monoalkylammonium salts. They also showed good foaming properties, but worse wetting capability. The obtained multiple salts showed excellent antielectrostatic properties.  相似文献   

2.
A series of new cationic gemini surfactants, bis(alkylammonium) dichlorides having a butenylene or a butynylene spacer, were prepared almost quantitatively by the reaction of a long-chain alkyldimethylamine with a highly reactive allylic or propargylic dichloride, and their surface-active properties were measured. All of them showed good water solubility and quite low critical micelle concentrations, which were more than one order of magnitude lower than those of the corresponding mono(alkylammonium) salts. They also showed quite high foaming ability and foam stability when they have an appropriate hydrophile-lipophile balance. Many of them showed almost the same antimicrobial activities against the eumycetes Aspergillus sp. and Candida albicans as commercial germicides such as benzalkonium chloride and chlorhexidine gluconate.  相似文献   

3.
非对称双子季铵盐阳离子表面活性剂的合成及性能   总被引:17,自引:0,他引:17  
以十二烷基二甲基叔胺、盐酸、环氧氯丙烷为原料,合成了中间体N-(3-氯-2-羟丙基)-N,N-二甲基十二烷基氯化铵,后与3种不同烷基链长的长链烷基叔胺反应,得到3种非对称Gemini季铵盐阳离子表面活性剂(Ⅰ~Ⅲ)。通过IR光谱,1HNMR确证了中间体及目的产物的结构。测定了产物的临界胶束浓度cmc及γcmc。cmc分别为1 07×10-3mol·dm-3、1 99×10-3mol·dm-3和9 55×10-3mol·dm-3,γcmc分别为40 9mN·m-1、48 0mN·m-1和50 9mN·m-1。结果表明:所合成的非对称Gemini季铵盐阳离子表面活性剂具有较高的表面活性。  相似文献   

4.
A convenient procedure for the synthesis of bis-quaternary ammonium salts from long-chain alkyldimethylamines and epichlorohydrin is studied. An improved preparation of bis-quaternary ammonium salts from N,N-dimethyloctylamine, N,N-dimethyldodecylamine or N,N-dimethyloleylamine, their amine hydrochlorides, and epichlorohydrin can be achieved by carrying out the reaction in an aqueous micellar medium. The amine hydrochlorides are used as functional surfactants to produce the self-micellization and solubilization of reactants. The formation of micelles is a necessary condition for a successful quaternization. Comparison of the quaternization performance in ethanol, ethanol/water mixtures, and aqueous micellar medium leads to the conclusion that this micellar-improved synthesis enables easier and cheaper access to bis-quaternary ammonium salts by avoiding the formation of the mono-quaternary ammonium salts as intermediates, and by using water as solvent under mild reaction conditions. Mechanistic aspects of the quaternization reaction in micellized medium are also suggested.  相似文献   

5.
A number ofcis andtrans quatenary ammonium salts were synthesized from jojoba oil. All derivatives were found to be surface active agents, i.e., they reduced the surface tension to 35 dynes/cm−1, at very low concentrations. The relationship between the surface activity and the molecular structure is discussed.  相似文献   

6.
Preparation ofbis-quaternary ammonium salts from epichlorohydrin   总被引:1,自引:0,他引:1  
A novelbis-quaternary ammonium salt was prepared conveniently and almost quantitatively fromN,N-dimethyldodecylamine, its hydrochloride, and epichlorohydrin. Reaction ofN,N-dimethyldodecylamine with epichlorohydrin (in the presence of the amine hydrochloride) or various dichloro compounds was investigated by using1H nuclear magnetic resonance. The reaction route was studied by examining the reactivity of reagents with the amine and the effect of reaction temperature. The ease of the reaction with epichlorohydrin was found to be due to the assistance of amine hydrochloride in opening the epoxide ring and to neighboring-group participation by the hydroxyl group of the intermediatemono-ammonium salt in the quaternization step. Neighboring-group participation by the hydroxyl group in these quaternization reactions is also discussed.  相似文献   

7.
以N,N-二甲基十四胺和1,8-二溴辛烷反应生成了14-8-14型Gemini季铵盐表面活性剂,通过单因素试验优化了反应条件,确定较佳合成条件为:N,N-二甲基胺的用量为5 mmol,N,N-二甲基胺与二溴烷烃的摩尔比为2.2:1,溶剂乙腈用量为10 mL,反应温度为80℃,反应时间为24 h,在此条件下合成了24种m-n-m型Gemini季铵盐表面活性剂,大部分反应的收率大于80%。采用吊环法对产物的表面张力进行了测定,分别研究了疏水烷基链、连接基对Gemini季铵盐表面活性剂表面活性的影响,研究发现,当连接基n相同时,随着疏水烷基链的增长(m10时),Gemini季铵盐表面活性剂的表面张力呈现先减小后增大的趋势,14-n-14型Gemini季铵盐表面活性剂呈现出最好的表面活性;当疏水烷基链m=14时,随着连接基n的增大,Gemini季铵盐表面活性剂的表面张力呈现先增大后减小的趋势。  相似文献   

8.
A series of novel carbamate group-containing quaternary ammonium salts (QASs) have been synthesized, which were subsequently used as antimicrobial agent and incorporated into polyurethane coatings through crosslinking with terpene-based polyol and polyisocyanate. The chemical structures of QASs were characterized by FT-IR, 1H NMR, and 13C NMR. The effects of QASs on the properties of coatings were investigated. The results showed that the resulting coatings exhibited significant antimicrobial activity against both Staphylococcus aureus and Escherichia coli by introducing QASs into the polyurethane networks. Furthermore, with the increasing of QAS content, the antimicrobial activity and adhesion of the coatings were enhanced, while the pencil hardness, water resistance and thermal stability of the coatings were decreased.  相似文献   

9.
New cationic surfactants, bis-quaternary ammonium salts, were prepared from N,N-dimethylaminoalkyl esters of saturated fatty acids and products of the reactions of epichlorohydrin with primary amines: pentyl-, hexyl- and octylamine. The bis (ester–ammonium) salts obtained were examined in respect to their surface-active properties: critical micelle concentration (CMC), effectiveness of surface tension reduction (γCMC), and adsorption efficiency (pC20). All these surfactants showed good water solubility and low critical micelle concentrations of more than two orders of magnitude lower than these of corresponding mono-alkylammonium salts. They also showed good wetting capability, but worse foaming properties. All the surfactants tested were nontoxic to gram-negative bacteria, but some of them inhibited the growth of gram-positive bacteria and yeast.
Jan ChlebickiEmail:
  相似文献   

10.
Novel cationic gemini surfactants, 1,3-bis[(acyloxyalkyl)dimethylammonio]-2-hydroxypropane dichloride, which possess hydrolyzable oxycarbonyl moieties in the lipophilic portions, were prepared. These surfactants showed much better micelle-forming ability, ability to lower surface tension, foaming ability, and foam stability than corresponding single-chain surfactants. Their surface properties were largely influenced by changing the position of the oxycarbonyl group in the lipophilic moiety. The critical micelle concentration decreased with a decreasing number of methylene units in the linking moiety between the ammonio and the oxycarbonyl groups within the comparison of lipophilic chains of the same length. These cationic gemini surfactants also showed good biodegradability.  相似文献   

11.
含酯基不对称双季铵盐表面活性剂的合成   总被引:6,自引:0,他引:6  
以长链烷基叔胺、盐酸、环氧氯丙烷为原料,合成了N (3 氯 2 羟丙基) N,N 二甲基长链烷基氯化铵,研究了其合成工艺,优化反应条件为:n(长链烷基叔胺)∶n(盐酸)∶n(环氧氯丙烷)=1∶1∶1 1,反应温度为40℃,体系pH=6~7。以月桂酸及2 二甲氨基乙醇为原料,酯化得到二甲基月桂酸乙基叔胺(Ⅲ),利用其与N (3 氯 2 羟丙基) N,N 二甲基长链烷基氯化铵季铵化得到含酯基不对称双季铵盐阳离子表面活性剂〔长链烷基分别为(Ⅰ)C12H25和(Ⅱ)C14H29〕。经测定,产物的临界胶束浓度CMC分别为6 61×10-3、8 31×10-3mol·L-1,γCMC分别为37 6、39 2mN·m-1,证明所合成的含酯基不对称双季铵盐阳离子表面活性剂具有较高的表面活性。  相似文献   

12.
周明  钟祥  赵焰峰  宋尧  庞淼  何磊 《化学试剂》2013,35(8):738-740
双子表面活性剂是具有高的表面活性的一类新型表面活性剂,但是,由于其生产成本过高而限制了其应用范围。以脂肪醇、环氧氯丙烷、1,2-二氯乙烷、亚硫酸钠、亚硫酸氢钠和四丁基溴化铵等为原料合成一种由两个疏水烃基和两个磺酸基组成的双子表面活性剂。该合成方法原料成本较低,而且分子结构中各基团间由醚键连接。将中间产物3-辛氧基-2-羟基-1-丙烷磺酸钠(OHPS)和终产物1,2-二(1-辛烷氧基-3-磺酸钠-2-丙烷氧基)乙烷(DOSPE)的表面活性进行比较,DOSPE的cmc较OHPS低一个数量级,但γcmc相反,并且DOSPE的表面活性剂具有优良的抗盐性能。  相似文献   

13.
采用温和的Mannich反应和O-烷基化反应,制得了高级脂肪胺/甲醛改性木质素季铵盐阳离子沥青乳化剂,对影响Mannich反应的一些因素进行了探讨.结果表明,Mannich反应在二氧六环水溶液均相介质中进行,可明显提高反应效率;反应温度为60℃;随十八胺用量增加,木质素胺的含氮量增加;甲醛与十八胺的摩尔比为1.5∶1时,改性产物的含氮量最高.基本表面物化性能测试表明,在不同链长的高级脂肪胺/甲醛改性木质素季铵盐中,以十二胺/甲醛改性产物的表面活性最好,表面张力为33.2 mN•m-1,较木质素季铵盐的43.8 mN•m-1明显降低.乳化能力也显著提高.沥青微粒表面的Zeta电位比木质素季铵盐上升得更快.  相似文献   

14.
采用荧光分光光度法和Zeta电位法考察了系列Gemini双季铵盐表面活性剂与阴离子表面活性剂十二烷基苯磺酸钠(SDBS)和十二烷基磺酸钠(SDS)的复配效果。结果表明,Gemini双季铵盐表面活性剂疏水链和连接基越长,cmc越小,且疏水链长度对表面活性剂性能的影响较大;Gemini双季铵盐表面活性剂的加入可显著提高阴离子表面活性剂SDBS和SDS的表面活性,当Gemini双季铵盐表面活性剂与SDBS或SDS的摩尔比为3:7时,复配体系的cmc最小,且与SDS复配体系的性能优于与SDBS的复配体系。  相似文献   

15.
A new type of cationic surfactant, 6-O-monoesters of 3-(trimethylammonio)propyl d-glucopyranoside, was prepared in high yield by a simple chemoenzymatic synthesis. Surface-active properties of the compounds were found to be highly dependent on the fatty acyl chain length in the 6-O-position with the dodecanoyl and tetradecanoyl esters exhibiting the highest ability to lower surface tension as well as having the lowest critical micelle concentration values. Furthermore, the dodecanoyl ester had excellent foaming properties. The new surfactants also showed antimicrobial activity. Thus, the most potent compound, the dodecanoyl ester, was able to inhibit growth of both bacterial (Gram-positive as well as Gram-negative) and fungal test strains. The antimicrobial effect was somewhat weaker compared to benzalkonium chloride, one of the most frequently used cationics for topical disinfection. However, compared to benzalkonium chloride, the new cationics exhibit a highly improved compatibility with anionic surfactants, as no precipitation took place even in highly concentrated solutions thereby providing a much more robust antimicrobial system. Finally, the new surfactants are expected to be readily biodegradable because they are carbohydrate ester-based.  相似文献   

16.
A series of dimethylaminopropyl benzyl chloride grafted polysiloxanes (PDMS-g-BCs) with tunable molecular weights and cationic content were synthesized, and the effect of polymer structure on the antimicrobial activities against bacteria (Escherichia coli (E. coli) and Staphylococcus albus (S. albus)) and phytopathogenic fungi (Rhizoctonia solani (R. solani) and Fusarium oxysporum f. sp. cubense race 4 (Foc4)) were systematically assessed. The antibacterial activity was evaluated by determining the minimum inhibitory concentration (MIC) against E. coli and S. albus by the broth dilution method, and the antifungal activity was measured by mycelia growth inhibition as well as by the MIC and minimum fungicidal concentration (MFC) values. The molecular weight and cationic content were major determinants of the activities of PDMS-g-BCs; when the molecular weight was approximately 2500 g/mol and the cationic content was approximately 20 mol% of the total siloxane units, PDMS-g-BCs gained strong antimicrobial activities toward both E. coli and Foc4, comparable to those of a commonly used broad-spectrum microbicide benzalkonium chloride, making PDMS-g-BCs promising fungicidal agents for plant disease control.  相似文献   

17.
Several lipoamino acids were synthesized, in which n-octadecanoic acid (stearic acid) was coupled with the α-amino group of an amino acid. The products were characterized and their identities confirmed by advanced analytical techniques like Fourier transform infrared 1H nuclear magnentic resonance spectroscopy, and differential scanning, calorimetry. Their surface properties, such as critical micelle concentration (CMC) and foaming properties, biodegradability, and antimicrobial activity were also evaluated. The N-stearoyl amino acids (NSA) had low CMC values, and some of them showed good foaming properties. They were screened for antimicrobial activity against the gram-positive bacteria Staphylococcus aureus, Micrococcus luteus, and Bacillus cerceus, the gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa, and the yeast Candida albicans. All the compounds inhibited at least one of these organisms. N-Stearoyl proline was the most effective, the order of antimicrobial activity being aromatic NSA> acidic NSA>basic NSA. However, the effective inhibition by all the compounds indicates the desirability of more thorough investigation and suggests that some of these compounds may have potential utility as biostatic additives in commercial products. All NSA are highly biodegradable and can readily be removed under conditions of normal secondary sewage treatment.  相似文献   

18.
A homolog pure nonionic surfactant, tetra(ethylene glycol) mono-n-octaneamide, was synthesized. The surfactant was characterized by determining the critical micelle concentration, cloud point, and biodegradation. Hydrolysis catalyzed by an acid, an alkali, a peroxide, and enzymes [peptidase from porcine, amidase from Pseudomonas aeruginosa, and two lipases, Mucor miehei lipase (MML) and Candida antarctica lipase B (CALB)] was investigated using 1H nuclear magnetic resonance. The surfactant was stable toward the acid, alkali, and peroxide. When subjected to peptidase and CALB, the amide was cleaved, although at a low rate. No reaction was obtained when using the amidase or MML. The biodegradation test resulted in more than 60% degradation after 28 d. Based on these results, the amide surfactant can be considered chemically stable, yet highly biodegradable, which generally is an ideal combination of properties for a surfactant.  相似文献   

19.
New bis-quaternary pyrimidinium surfactants were synthesized by reacting 4-amino-5-phenyl-pyrimidine with alkylene dibromides (C8−C12). Structural assignments of the new compounds were made on the basis of elemental analysis, infrared, and 1H nuclear magnetic resonance spectroscopy. Critical micelle concentrations, as determined by tensiometry, were lower than those of previously studied corresponding monoquats. The rate of drop coalescence in an oil (hepatane)/water emulsion of a bis-quat was lower than that of the corresponding monoquat, showing a higher emulsification efficiency for the former.  相似文献   

20.
罗利娟  胡星琪  耿向飞  陈明贵  杨彦东 《应用化工》2011,40(11):1935-1937,1941
以甲胺醇溶液、环氧氯丙烷、十二胺、十六胺、十八胺为主要原料,合成出一种新型的表面活性剂BHMDn,(n=12,16,18,代表两端烷基链的碳原子个数),考察其的表面活性以及盐对其表面活性的影响。结果表明,目标产物水溶液的cmc分别为1×10-4,6×10-5,5×10-5 mol/L;临界胶束浓度下的表面张力rcmc分别为27.4,21.5,19.6 mN/m。目标物与十二烷基苯磺酸钠(SDBS)复配产生了较好的协同效应。  相似文献   

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