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1.
合成了一系列可裂解Gemini型季铵盐表面活性剂烷基-α,ω-双(二甲基酰氧乙基溴化铵),标记为Ⅱ-m-n(m=12,14;n=3,4,6);采用红外光谱和核磁共振进行结构表征.测定了相关的性能,结果表明,可裂解Gemini型季铵盐表面活性剂具有很强的胶束生成能力,其临界胶束浓度(CMC)为2.63×10-4~4.17×10-4mol/L(m=12)及2.88×10-5~4.46×10-5mol/L(m=14),分别比相应的单季铵盐表面活性剂的临界胶束浓度(CMC)低两个数量级;其泡沫稳定性、乳化性能和杀菌性明显优于相应的单季铵盐表面活性剂.  相似文献   

2.
酯基Gemini型季铵盐表面活性剂的合成与性能   总被引:2,自引:0,他引:2  
许虎君  吕春绪  陆明  叶志文 《江苏化工》2005,33(Z1):185-188
合成了一系列酯基Gemini型季铵盐表面活性剂烷基-α,ω-双(二甲基酰氧乙基溴化铵),标记为II-m-n(m=12,14;n=3,4,6);采用红外光谱和核磁共振进行结构表征.测定了相关的性能,结果表明,酯基Gemini型季铵盐表面活性剂具有很强的胶束生成能力,其临界胶束浓度(cmc)为2.63×10-4~ 4.17×10-4 mol·L-1(m=12)及2.88×10-5~ 4.46×10-5 mol·L-1(m=14),分别比相应的单季铵盐表面活性剂的临界胶束浓度低两个数量级;其泡沫稳定性、乳化性能和杀菌性明显优于相应的单季铵盐表面活性剂.  相似文献   

3.
Gemini型表面活性剂具有双亲水基及双亲油基的特殊结构,能极大地提高表面活性。本文综述了各类季铵盐型Gemini表面活性剂的合成工艺,重点介绍了不同季铵盐型Gemini表面活性剂的合成路线,讨论了合成中存在的问题,展望了今后的发展趋势。  相似文献   

4.
以十二胺、环氧氯丙烷、十二叔胺等为原料,无水乙醇为溶剂合成了季铵盐型Gemini表面活性剂,应用红外光谱表征其结构,并测定其熔程。考察了产物水溶液的表面活性,并计算出产品的饱和吸附量(Fmax)和单分子饱和吸附面积(Amin)。实验结果表明Gemini表面活性剂CMC为0.8mmol/L、γcmc为35.7mN/m、Amin为2.04nm^2,有较高的表面活性,与具有相同单尾基链的传统表面活性剂十二烷基三甲基氯化铵(DTAC)R十二烷基硫酸钠(SDS)相比,其表面张力相当,但CMC分别比DTAC、SDS低约15、11倍,Amin分别比DTAC、SDS高约4倍。  相似文献   

5.
Gemini型季铵盐表面活性剂的合成及应用   总被引:3,自引:0,他引:3  
本文介绍了Gemini型季铵盐表面活性剂的结构,综述了近年来Gemini型季铵盐表面活性剂的合成研究进展及该类表面活性剂的应用情况。  相似文献   

6.
Gemini型表面活性剂具有双亲水基及双亲油基的特殊结构,能极大地提高表面活性。本文综述了各类季铵盐型Gemini表面活性剂的合成工艺,重点介绍了不同季铵盐型Gemini表面活性剂的合成路线,讨论了合成中存在的问题,展望了今后的发展趋势。  相似文献   

7.
通过体积滴定法测定季铵盐Gemini表面活性剂水溶液的表面张力.由此得到其临界胶束浓度(cmc),并且利用稳态荧光猝灭法测定胶柬聚集数Nm,进一步说明了此类表面活性剂水溶液很明显的胶团化倾向。  相似文献   

8.
Gemini(双子)型双季铵盐阳离子表面活性剂以其独特的结构而具有良好的表面活性、较低的临界胶束浓度(CMC)等优良的物理性能。以间隔基团的不同综述了Gemini型双季铵盐阳离子表面活性剂的合成路线,并简要的介绍了Gemini型双季铵盐阳离子表面活性剂在杀菌、金属缓蚀、煤沥青润湿、乳化及作为基因和药物载体方面的应用,为Gemini型双季铵盐阳离子表面活性剂的后续研究提供了参考。并指出要重视其合成条件的优化,以降低生产成本,扩大Gemini型双季铵盐阳离子表面活性剂的应用范围。  相似文献   

9.
磺酸型Gemini表面活性剂的合成及表面活性   总被引:2,自引:0,他引:2  
李晨  杨继萍  陈功 《应用化工》2007,36(5):425-427,456
以壬基酚、1,4-二溴丁烷和氯磺酸为主要原料,通过三步反应合成了新型的磺酸型Gemini表面活性剂9BA-4-9BA,讨论了合成反应时间、温度以及催化剂对产物纯度和产率等因素的影响,优化了反应过程。利用核磁共振谱和红外光谱表征了产物结构,并通过DCTA21表面/界面张力仪测试其水溶液中的表面张力。和传统表面活性剂相比,合成的Gemini表面活性剂9BA-4-9BA具有更高的表面活性,其临界胶束浓度和C20分别为6.2×10-4mol/L和1.1×10-5mol/L。  相似文献   

10.
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   

11.
以咪唑、以咪唑,溴乙酸,溴代十四烷和二元醇为主要原料,采用三步法合成了三种新的咪唑型双子表面活性剂,简记[C_(14)-n-C_(14)]Br_2。通过核磁氢谱和红外光谱对三种产物的结构进行表征,证明合成的产物为目标产物。并采用表面张力法得出三种表面活性剂的表面张力曲线,进而计算临界胶束浓度(CMC)等一系列表面性能参数,结果表明,连接基越短的咪唑型双子表面活性剂拥有更低的CMC,更高的界面活性。  相似文献   

12.
以芘为荧光探针、二苯酮为猝灭剂,用稳态荧光探针法测定了新型Gemini表面活性剂的临界胶团浓度(CMC)、胶团聚集数(Nagg)及胶团微极性.研究了Gemini表面活性剂结构和氯化钠浓度对CMC、Nagg、胶团微极性的影响.结果表明,新型Gemini表面活性剂的CMC比常规表面活性剂的CMC低1—2个数量级.当疏水基碳原子数增加时,CMC依次降低,Nagg增大,胶团微极性减小.当氯化钠浓度增大时,Nagg增大,胶团微极性减小.  相似文献   

13.
Gemini表面活性剂的性质研究   总被引:7,自引:0,他引:7  
王月星  韩冬  鲁毅强  王红庄 《化学世界》2005,46(11):696-700
Gemini表面活性剂通常是由两(或三)条疏水链、两个亲水基和一个连接基组成的两性分(离)子,与由单亲水基和单疏水链构成的传统表面活性剂分(离)子相比较,在临界胶团浓度、界面性质等方面有着独特的性质。详述了该类新型表面活性剂的性质,比较了与传统表面活性剂的差别。  相似文献   

14.
A series of novel cationic gemini surfactants, namely 1,3-adamantanedicarboxylic acid bis(alkyldimethyl-3-ammoniopropyl amide) dibromide designated as [Ad-2(amC n )] (n = 12, 14, 16), containing adamantane, two amide groups, and two hydrocarbon chains, were synthesized from 1,3-adamantanedicarboxylic acid. The surface-active properties of the surfactants were investigated through surface tension and electrical conductivity measurement. A series of thermodynamic parameters such as standard free energy \(\left( {\Delta G^\circ_{\text{m}} } \right)\) , enthalpy \(\left( {\Delta H^\circ_{\text{m}} } \right)\) , and entropy \(\left( {\Delta S^\circ_{\text{m}} } \right)\) of micellization were evaluated from electrical conductivity measurements in the temperature range from 288 to 308 K. The micellization for [Ad-2(amC n )] is entropy-driven at low temperature and enthalpy-driven at high temperature. Further, the antimicrobial activity of the synthesized gemini surfactants against both Gram-positive and Gram-negative bacteria was also investigated, and this study showed that the compound [Ad-2(amC12)] has excellent antibacterial activity against all studied bacteria.  相似文献   

15.
In the present work, a two-step method was adopted to synthesize a series of novel Gemini surfactants using N,N-dimethylalkyl amines (alkyl length = C12, C16 and C18), epichlorohydrin, and n-phenyllenediamine as starting materials. The products were characterized using mass spectroscopy (MS) and nuclear magnetic resonance spectroscopy (1H NMR). Systematic experiments were conducted to evaluate their surface activity, foaming properties, and antibacterial performance. Results showed the critical micelle concentrations (CMC) of the C12-based, C16-based, and C18-based phenylenediamine surfactants were 3.295 × 10−3, 2.532 × 10−4, and 3.140 × 10−4 mol L−1 at 298 K, respectively, with corresponding surface tension (γcmc) values of 28.24, 31.95, and 35.06 mN m−1 under the same conditions. The Gemini surfactants showed not only good surface activity and foaming properties, but also demonstrated good antimicrobial performance against Gram-positive and Gram-negative bacteria and fungi.  相似文献   

16.
叶俊  华平  方略韬 《广东化工》2011,38(5):7-8,21
文章介绍了近年来报道的磺酸系Gemini表面活性剂的种类、合成方法;并概括了这类表面活性剂的理化和应用性能,包括临界胶束浓度、表面张力、增溶能力、润湿性能、抗盐能力、泡沫性能及特殊的流变性能等。  相似文献   

17.
The surface activity and aggregation behavior of partially fluorinated gemini surfactant N,N′‐bis(3‐perfluorohexyl‐2‐hydroxypropyl)‐N,N′‐dipropanesulfonylhexylenediamine (N‐6‐Sul) was studied by surface tension, resonance light scattering and fluorescence spectra measurements. The critical micelle concentration (CMC) values obtained by the three methods are in good agreement. The surface activity parameters such as the effectiveness of surface tension reduction (Πcmc), the maximum surface excess concentration (Γmax) and the minimum surface area per molecule (Amin) were obtained through surface tension curves. The effects of pH, inorganic salts and temperature on the surface activity were also investigated. The morphology and size of the aggregates of N‐6‐Sul were examined by transmission electron microscopy (TEM). The results show that the partially fluorinated gemini surfactant N‐6‐Sul has many advantages such as high surface activity, low CMC value, great salt tolerance and temperature resistance.  相似文献   

18.
A series of novel cationic gemini surfactants with rigid amido groups inserted as the spacers, named C 12 ‐PPDA‐C 12 , C 14 ‐PPDA‐C 14 and C 16 ‐PPDA‐C 16 , were synthesized by a two‐step reaction with dimethyl terephthalate, N,N‐dimethyl propylene diamine and alkyl bromide as raw materials. The chemical structures of the prepared compounds were confirmed by IR, 1H and 13C NMR and element analysis. Surface activity properties of the synthesized compounds were investigated by surface tension, electrical conductivity and fluorescence. Increasing the number of carbon atoms in the hydrophobic alkyl chain, decreased the critical micelle concentration (CMC), surface tension at the CMC and the minimum surface area. Other relevant properties including foaming ability and emulsion stability were investigated. The results indicated that the synthesized gemini surfactants possess good surface properties, emulsifying properties and steady foam properties.  相似文献   

19.
In this study, the gemini surfactants of the alkanediyl-α-ω-bis(alkyl dimethyl ammonium) dibromide type, on the one hand, with different alkyl groups containing m carbon atoms and an ethanediyl spacer, referred to as “m-2-m” (m = 10, 12 and 16) and, on the other hand, with n-C16 alkyl groups and different spacers containing s carbon atoms, referred to as “16-s-16” (s = 2, 6, 10 and Ar (8)) have been synthesized, purified and characterized. The critical micelle concentration (CMC), micelle ionization degree (α) and Gibbs free energy of micellization (∆G mic) of these surfactants and the monomeric cationic surfactants DTAB and CTAB have been determined by means of electric conductivity measurements. In addition, the temperature dependence of the CMC was determined for the 10-2-10 gemini surfactant. The CMCs of the gemini surfactants are found to be much lower than those of the corresponding monomeric surfactants and the effect of the hydrophobic alkyl chain length is more important than that of the spacer. The CMC of 16-s-16 passes through a maximum of (or around) s = 6 and then decreases for s = 10. The presence of a maximum CMC is explained by the contribution of a change of conformation of the surfactant with increasing spacer chain length. The changes of α with s and m are found qualitatively similar to those found for CMC values. The values of ∆G mic are more negative for the dimers than for the monomers and also change with an increasing spacer carbon number, as CMC values do. The thermodynamic parameters of micellization indicate that the micellization of 10-2-10 is enthalpy driven.  相似文献   

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