首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 125 毫秒
1.
分别将Gemini型单体1,3-双(二甲基十四烷基溴化铵)-2-丙烯酰氧基丙烷(14G)或1,3-双(二甲基十六烷基溴化铵)-2-丙烯酰氧基丙烷(16G)与丙烯酰氧乙基三甲基氯化铵(DAC, D)共聚合反应, 合成了新型含Gemini表面活性剂结构单元的两亲性阳离子聚电解质(D14G和D16G). 采用稳态荧光、电导、动态光散射及透射电镜等手段研究了这些聚电解质在水溶液中的聚集行为. 结果表明, 临界聚集浓度(CAC)随着Gemini型表面活性剂单元含量的增加而减小, 同时随着Gemini型表面活性剂单元中疏水碳链长度的增加而降低. 这些聚电解质在水溶液中同时存在分子内和分子间两种类型的聚集体, 而且碳链越长, 形成分子内聚集体的倾向越强. 随着Gemini表面活性剂单元含量的增加, D14G溶液中聚集体的流体动力学半径(Rh)也有所增大, 而D16G溶液中的聚集体的流体动力学半径(Rh) 却略有减小.  相似文献   

2.
油/水界面表面活性剂的复配协同机制   总被引:3,自引:0,他引:3  
采用耗散颗粒动力学(DPD)方法模拟了椰油酸二乙醇酰胺(6501)分别与十二烷基-α-烯烃磺酸钠(DAOS)、椰油酰胺丙基二甲基甜菜碱(CAB)和十二烷基苯磺酸钠(SDBS)复配体系中表面活性剂在油/水界面的排布行为, 探讨了盐度及分子结构对单一和复配表面活性剂界面活性的影响, 从界面效率、界面密度和分子排布等角度讨论了油水界面表面活性剂混合体系的复配协同增效机制.  相似文献   

3.
用聚合表面活性剂作增敏试剂分光光度测定钼和钨   总被引:2,自引:0,他引:2  
刘昆元  俞汝勤 《化学学报》1987,45(6):584-589
采用表面活性剂的分光光度分析法应用日趋广泛。这方面的研究工作虽极活跃,但较多工作限于已有经典表面活性剂的研究与应用,为分析化学的特定需要设计与合成新型表面活性剂的研究尚少。作者曾用环氧氯丙烷和长链烷基叔胺合成了以聚乙二醇为主链含有若干个带长链烷基的季氮支链的低聚合表面活性剂——聚(氧化丙烯)-α-十八烷基二甲基氯化铵(PPOSA)。实验表明,这类表面活性剂兼有阳离子和非离子表面活性剂的某些特性。本文  相似文献   

4.
以长链溴代烷烃和叔胺合成了十四烷基二甲基羟丙基溴化铵(C14-2-1-1)、十六烷基二甲基羟丙基溴化铵(C16-2-1-1)、十八烷基二甲基羟丙基溴化铵(C18-2-1-1)阳离子表面活性剂.测定这3种阳离子表面活性剂的临界胶束浓度(cmc)值和表面张力,结合产率高低,选取C18-2-1-1作为压裂液用黏弹性表面活性剂...  相似文献   

5.
表面活性剂的电喷雾质谱分析   总被引:1,自引:0,他引:1  
采用不同的质谱采集模式分析了不同类型的表面活性剂。阳离子表面活性剂如氯化十二烷基二甲基苄基铵,适合正离子采集模式,准分子离子为其阳离子;阴离子表面活性剂如十二烷基苯磺酸钠,适合负离子采集模式,准分子离子为其阴离子;两性表面活性剂如氧化十四烷基二甲基胺,适合负离子采集模式,准分子离子为[M-H]^-;非离子表面活性剂如壬基酚聚氧乙烯(12)醚,适合正离子采集模式,准分子离子为[M+Na]^-。  相似文献   

6.
报道了1-(5-萘酚-7-磺酸)-3-[4-(苯基偶氮)苯基]-三氮烯(NASAPAPT)的合成,研究了该试剂与阳离子表面活性剂溴化十二烷基二甲基苄铵(DDMBAB),溴化十六烷基三甲铵(CTMAB)、溴化十六烷基吡啶(CPB)、溴化十四烷基吡啶(TPB)显色反应的条件。测定了显色反应的灵敏度,符合比尔定律的范围。建立了光度法测定微量阳离子表面活性剂的新方法。  相似文献   

7.
将阳离子表面活性剂、非离子表面活性剂和阴阳离子表面活性剂应用于铝(Al)-铬天青S(CAS)体系以测定微量铝,已有不少报导,对提高反应的灵敏度,改善反应条件取得了良好的效果,有的体系已用于钢铁中微量铝的测定。我们曾把两性表面活性剂用于稀士元素的分析,表现出灵敏度高,选择性强,水溶性、稳定性好等优点。本文试图把两性表面活性剂应用于Al-CAS体系,研究其分光光度性质和反应机理,并寻求一个高灵敏度测定微量铝的新方法。试验证明,两性表面活性剂:N-十二烷基二甲基铵基乙酸(DDMAA),N-十二烷基二聚氧乙烯铵基乙酸(DDPAA)均能与铝、铬天青S形成三元胶束络合物,并表现出突出  相似文献   

8.
通过表面张力的测定研究了皂荚素(GS)的表面活性及其热力学性质随温度的变化.测定了皂荚素分别与十二烷基磺酸钠、十二烷基聚氧乙烯醚硫酸钠、全氟辛酸钠、十二烷基脂肪醇聚氧乙烯(9)醚、辛基酚聚氧乙烯(10)醚及十六烷基三甲基溴化铵等复配的表面张力-浓度对数关系(γ~lgc)曲线,并用二维晶格模型及正规溶液理论计算了含皂荚素的二元表面活性剂溶液表面吸附层的组成、分子相互作用参数及分子交换能.结果表明,皂荚素主要呈现非离子表面活性剂的性质,与阳离子表面活性剂复配呈微弱的离子性.复配后分子交换能均小于零,复配增效.增效顺序为GS/阳离子>GS/非离子>GS/阴离子(表面活性剂复配体系).  相似文献   

9.
在NaOH碱性介质中,1 (3 硝基苯基) 3 [4 (苯基偶氮)苯基] 三氮烯(m NPPAPT)分别与阳离子表面活性剂(CS)溴化十六烷基三甲铵(CTMAB)、溴化十二烷基二甲基苄铵(DDMBAB)、溴化十六烷基吡啶(CPB)和溴化十四烷基吡啶(TPB)反应显色形成离子配合物,它们与m NPPAPT形成离子配合物比均为2∶1。CTMAB、CPB、TPB、DDMBAB与m NPPAPT形成配合物最大吸收波长分别位于538、538、625、637nm,表观摩尔吸光系数达(103~104)L·mol-1·cm-1。研究了测定微量阳离子表面活性剂的条件,建立了新的分析方法,并应用于实样分析。  相似文献   

10.
合成了四种季铵盐型阳离子表面活性剂,C16H33N(N2H5)3Br(十六烷基三乙基溴化铵),C16H33N(CH3)2C12H25Br(十六烷基十二烷基二甲基溴化铵),C22H45N(CH3)3I(二十二烷基三甲基碘化铵)和C22H45N(CH3)2C16H33Br(二十二烷基十六烷基二甲基溴化铵),考察其在水-有机两相体系中对Rh-TPPTS催化的长链烯烃氢甲酰化反应的促进作用。结果表明,表面活性剂中疏水长链和阳离子头的变化对催化性能有重要影响,疏水长链的增长和疏水长链数目的增加、小的阳离子头均有利于加快催化反应的速度,而疏水长链对催化活性的影响更为显著。  相似文献   

11.
合成了3种含季氮原子及羟基的同系列分析增敏试剂十六烷基(2-羟乙基)二甲基氯化铵(HEMAC)、十四烷基(2-羟乙基)二甲基氯化铵(TEMAC)和十二烷基(2-羟乙基)二甲基氯化铵(DEMAC),测试其基本物性,并用作测定微量钪、铁(Ⅲ)、锗的增敏试剂,获得了与阳离子表面活性剂及醇类有机溶剂联用时相仿的增敏效果。  相似文献   

12.
Two new polymer surfactants poly(propylene oxide)-a-tetradecyl-dimethylammonium chloride(PPOTA) and poly(propylene oxide)-a-cetyl-dimethylammonium chloride(PPOCA) were synthesized,which possess the characteristics of both cationic and nonionic surf actants.The properties of PPOTA and PPOCA were investigated.The synthesized surfactants can be used as sensitizing and solubilizing reagents for spectrophotometric analysis.Some examples of micellae improved by spectrophotometric systems such as Sc(Ⅲ)-CAS,Ge(Ⅳ)-PF and Ni(Ⅱ)-CAS were given.  相似文献   

13.
The synthesis of four sugar-based surfactants derived from glucose and (R)-12-hydroxystearic acid is described. The surfactants have a hydroxy group in the hydrophobic part, which is either free or acylated using acetyl chloride, hexanoyl chloride, or myristoyl chloride. Three of the synthesized surfactants are water-soluble and are evaluated with respect to their CMCs and hemolytic activities. The fourth surfactant has limited water solubility and is not further included in the study. The investigated surfactants are all hemolytic close to their respective CMC indicating that their use in parenteral formulations may be limited. Nevertheless, surfactants having the proposed structure appear as promising alternatives to existing solubilizing agents for pharmaceutical applications.  相似文献   

14.
The synthesis and cloud point behavior of high oleate ester-derived nonionic surfactants are now reported. The effect of various polyethoxylate chain lengths (polyethylene glycol with 7, 11, and 16 units of ethylene oxide (EO) monomer) as the surfactant's hydrophilic head on the cloud point was investigated. The effect of varying amounts of sodium chloride and five different ionic surfactants on the cloud points of the synthesized nonionic surfactants were also presented. When the chain length of polyethoxylate increased, the cloud point of the synthesized nonionic surfactant also increased, ranging from 16°C, 43°C, and 64°C for 7, 11, and 16 EO units, respectively. Increments in sodium chloride concentration depressed the cloud point values of the synthesized nonionic surfactants linearly. The addition of ionic surfactants elevated the cloud points of the synthesized nonionic surfactant. However, in the presence of sodium chloride, the cloud point of the mixed ionic-nonionic solution was suppressed and anincrease in ionic surfactant concentration was required to elevate the cloud point. It was also found that the cloud points of synthesized surfactants can be raised up to 95°C in the presence of 4wt% NaCl solution.  相似文献   

15.
合成了一系列含有羟基的双子表面活性剂:1,3-双(十二烷基二甲基氯化铵)-2-丙醇(12-3OH-12),1,3-双(十四烷基二甲基氯化铵)-2-丙醇(14-3OH-14),1,3-双(十六烷基二甲基氯化铵)-2-丙醇(16-3OH-16)和1,3-双(十八烷基二甲基氯化铵)-2-丙醇(18-3OH-18).采用静态失重法、极化曲线和交流阻抗技术研究了其在H2S/CO2腐蚀环境中对L360钢的缓蚀作用.结果表明,三种研究方法取得的结论是一致的,缓蚀效果为14-3OH-14>12-3OH-12>16-3OH-16>18-3OH-18.其中,12-3OH-12和14-3OH-14都表现出很好的缓蚀效果,在35mg·L-1的较低浓度下缓蚀率就达95%以上.极化曲线测试结果表明n-3OH-n(n=12,14,16,18)型双子表面活性剂是一种以阳极抑制为主的混合型缓蚀剂.除n=18外,其它三种双子表面活性剂n-3OH-n(n=12,14,16)在L360钢表面的吸附服从朗缪尔等温线,并且属于物理和化学混合吸附.提出了一个用来解释双子表面活性剂在H2S/CO2溶液中缓蚀机理的吸附模型.  相似文献   

16.
双子型阴离子表面活性剂的合成及浮选性能   总被引:4,自引:0,他引:4  
姜小明  陈晓阁  解田 《应用化学》2010,27(6):742-744
分别以辛酰氯、癸酰氯、十二酰氯为原料,经加成、酰化及皂化等反应合成了3种双子型阴离子表面活性剂。产物结构经IR、1HNMR和13CNMR等波谱测试技术确定。25℃时测定了表面活性参数,结果表明随分子中疏水链增长,临界胶束浓度及表面张力均降低。目标化合物能一定程度增强油酸对胶磷矿中白云石的浮选能力。  相似文献   

17.
Two surfactants were synthesized by reacting hydrogen halides (hydrogen chloride and hydrogen bromide) with 1-dodecylamine. The resultant cationic surfactants, 1-dodecylammonium chloride (DDAC) and 1-dodecylammonium bromide (DDAB), were characterized by NMR spectrometry and FTIR spectroscopy and data related to their adsorption at the fluid liquid/gas interface were obtained employing bubble surface tensiometry, in pure water and in HCl 0.1 M. Data did not fit well to Langmuir isotherm but Frumkin isotherm did adequately describe to process of adsorption. Adsorption isotherms, as well as data related to critical micelle concentration, CMC, indicated that in HCl 0.1 M, the presence of electrolytes and a common ion to DDAC decreased chloride solvation, changing surface packing and adsorption profile for this surfactant.  相似文献   

18.
Compared with quaternary ammonium cationic surfactants with saturated alkyl chains, quaternary ammonium cationic surfactants with one double-bond in their alkyl chains, when mixed with appropriate counterions (in certain molar concentration ratios, ξ), can reach much lower effective drag-reduction temperatures, while maintaining the upper drag-reduction temperature limit of the corresponding saturated drag reducing surfactant solutions. No previous study has compared the effects of cis- vs. trans-unsaturated alkyl hydrocarbon tail configurations (oleyl vs. elaidyl) trimethyl ammonium chloride cationic surfactants at different counterion/surfactant concentration ratios on micellar nanostructures, (1)H NMR spectra and on rheological and drag-reduction behavior of their solutions. Since neither pure oleyl (cis-) nor elaidyl (trans-) trimethyl ammonium chloride surfactants are commercially available, they were synthesized and their 5mM solutions with NaSal counterion at concentrations of 5mM, 7.5mM and 12.5mM were studied.  相似文献   

19.
Two optically active cationic surfactants, (2S)-N-hexadecyl-N, N-dimethyl-(1-hydroxy-3-phenylpropyl)-2-ammonium chloride 1 and (2S)-N-hexadecyl-N,N-dimethyl-(1-hydroxy-4-methylpentyl)-2-ammonium chloride 2, have been selected and synthesized for use as enantioselective micellar catalysts in aqueous media. Their surface and aggregation behavior has been investigated at 298 K using surface tension and light scattering studies, which revealed that both molecules associate at low concentrations to produce micellar aggregates. Interestingly, although the area per molecule occupied by the surfactants at the air-water interface (43.6 ?(2) for 1 and 54.6 ?(2) for 2) is similar to that of related cationic surfactants, their aggregation number (23 for 1 and 19 for 2) is much smaller, perhaps reflecting the influence of the size or homochiral nature of the head group in the packing of the micelle. Copyright 2001 Academic Press.  相似文献   

20.
Liu KY  Yu RQ 《Talanta》1985,32(12):1163-1166
A new low-polymer surfactant, poly(propylene oxide)--stearyldimethylammonium chloride (PPOSA) has been synthesized. It contains a polyglycol main chain and quaternary ammonium branched chains. Investigation of the surface-active properties of PPOSA showed that as a sensitizing and solubilizing reagent for spectrophotometric analysis it possesses some of the characteristics of both cationic and non-ionic surfactants. The surfactant shows a sensitizing effect superior or equal to that of classical surfactants commonly used in analytical chemistry. Use of PPOSA leads to development of some excellent micellar spectrophotometric procedures for determining trace metals.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号