Gemini阳离子表面活性剂的合成及其胶束生成 Gemini阳离子表面活性剂的合成及其胶束生成

Cationic Gemini surfactants, alkanediyl-α,ω-bis(dimethyldodecylammonium bromide) have been synthesized by the following method: firstly dodecyl bromide was prepared by the reaction of dodecanol with bromic acid in the presence of strong sulfuric acid. Dodecylbromide was then reacted with N,N-tetramethyl ethane diamine(or N,N-tetramethyl hexana diamine) to prepare the title-compounds. Micellization of these Gemini surfactants was investigated using conductivity measurement. The results showed that the critical micelle concentration(cmc) of the Gemini surfactants has a much lower value compared with that of the corresponding “ monomer” . For a series of the Geminis with the same length(s) in the spacer chain, the cmc decreased with increasing the carbon number (m) in the alkyl chain. The aggregation number(N) of the micelle also drastically decreased with m. For the same value of m, the cmc varied slightly with s, which indicated that the electrostatic interaction between the ionic-groups of the “ monomer” has been naturally changed duo to a link between the two ionic-groups of the “ monomer” through a spacer. However, N was strongly decreased with s,which may be a reason of steric inhibition coming from the ionic-groups due to a link of spacer. With increasing temperature, micellization of the Gemini surfactants was slightly enhanced.     

含酰胺基Gemini阳离子表面活性剂的合成

含酰胺基Gemini阳离子表面活性剂的合成     

Gemini表面活性剂的研究进展

Gemini型表面活性剂是一类双亲油基双亲水基的两亲物，因其特殊的二聚结构从而具有许多特殊的物化性质。综述了Gemini型表面活性剂的研究进展、合成方法、物化性质及其应用。     

阳离子Gemini表面活性剂与PVA相互作用

阳离子Gemini表面活性剂与PVA相互作用;聚乙烯醇;粘度;表面张力     

一种阳离子Gemini型沥青乳化剂的合成及性能

以苯胺、环氧氯丙烷和十四烷基二甲基叔胺为原料,合成了含有苯环的阳离子Gemini型沥青乳化剂3,3'-苯基亚氨基-(二(2-羟基丙基-十四烷基二甲基)氯化铵)(G-T)。 采用傅里叶红外光谱(FT-IR)、质谱(MS)和核磁共振谱(¹H NMR)对产物进行了结构表征。 研究了其Krafft点、乳化性能和乳化沥青时的相关性能,并测定了25~40 ℃的临界胶束浓度(cmc)、平衡表面张力(γ_cmc)及计算了相应的热力学函数。 结果表明,G-T的Krafft点低于0 ℃,乳化分水时间为309 s。 25 ℃时,cmc为1.269×10^-3 mol/L,γ_cmc为38.33 mN/m。 随着温度的升高,cmc增大、γ_cmc减小、饱和吸附量(Γ_max)减小、极限占有面积(A_min)增大。 乳化沥青测试表明,G-T拌和时间为255 s,是慢裂型沥青乳化剂。 所制备的乳化沥青满足微表处技术规范。     

新型表面活性剂研究进展--Bola型表面活性剂与Gemini型表面活性剂

对两类新型表面活性剂--Bola型表面活性剂和Gemini型表面活性剂,从结构特点、研究历史、水中的溶解性与Krafft点、表面活性与表面吸附、临界胶团浓度、水中的聚集体类型与转化、研究前景等方面进行综述.     

Gemini表面活性剂合成进展

系统总结了近百种Gemini表面活性剂的合成路线和方法,并且按照其结构特点分门别类地进行比较和归纳,对今后Gemini表面活性剂的合成发展方向提出了一些看法,这对促进此类新颖表面活性剂的工业化进程将具有指导意义。     

Gemini阳离子表面活性剂的合成及其胶束生成

传统的单头基单烷烃链表面活性剂由于离子头基间的电荷斥力或水化引起的分离倾向使得它们在界面或分子聚集体中难以紧密排列,造成表面活性偏低 .为克服这一缺陷进行了大量尝试,例如添加无机电解质屏蔽离子头基的电荷斥力、升高温度以降低头基的水化,甚至采用合适的二元表面活性剂复配等等 .当前一种从根本上克服头基间分离倾向的化学方法正受到关注 [1],这种方法通过化学键将二个单头基单烷烃链表面活性剂在离子头基处用联接基团（ spacer）使其联接起来,从而获得称之为 Gemini的新型表面活性剂 [2]. Gemini表面活性剂大大促进了其 "…     

季铵盐型Gemini表面活性剂在金表面的吸附行为

以邻苯二酚(CC)为电化学探针, 利用循环伏安、交流阻抗等方法研究了不同阳离子Gemini表面活性剂(C16H33(CH3)2N-C4H8-N(CH3)2C16H33 (C16-C4-C16)、C12H25(CH3)2N-C4H8-N(CH3)2C12H25 (C12-C4-C12)、C8H17(CH3)2N-C4H8-N(CH3)2C8H17 (C8-C4-C8))在金电极表面的吸附性能. 结果表明, CC在KNO3溶液中可产生两对峰; 当向溶液中加入阳离子Gemini表面活性剂时, 第一对峰降低, 第二对峰升高, 峰电位差变大; 碳链长的表面活性剂对CC的氧化还原峰的影响较大. 同样, 碳链长的表面活性剂使电极界面的阻抗增大较多, 使石英晶片的频率变化较大. 根据CC的第一个氧化峰的面积随表面活性剂吸附的变化, 估测了它们的吸附模式. 发现这三种表面活性剂在金电极表面的吸附基本符合Langmuir吸附模型.     

磺酸盐型Gemini表面活性剂合成研究进展

磺酸盐型Gimini表面活性剂是一类新型的阴离子表面活性剂,它由联结基团通过化学键将2个或多个单体磺酸盐型表面活性剂连接在一起,由此产生高表界面活性,低临界胶束浓度值,增强了洗涤能力,与传统的阴离子表面活性剂有较好的复配性,奇异的流变特性和良好的抗盐性等一系列的性质,从而具有广泛的应用前景。 本文以原料来源不同分类,综述了一系列磺酸盐型Gemini表面活性剂的合成方法,展望了合成磺酸盐型Gemini表面活性剂的研究方向。     

煤沥青可溶组分在甲苯中缔合行为的研究

采用流体力学参数法研究了煤沥青可溶组分TS在甲苯中的缔合行为,确定了TS在甲苯中不同温度下的临界缔合浓度,并计算出缔合过程中成核阶段和成团阶段的缔合动力学参数。结果表明,293~353 K,TS溶液黏度随浓度的增加而增加,在13~26 g/L的浓度时出现了拐点,且拐点随温度升高而沿坐标轴方向右移。成核阶段和成团阶段均为一级缔合反应,两阶段活化能分别为17.25和12.41 kJ/mol。     

基于醛类交联剂的煤焦油沥青族组分改性石油沥青

以中温煤焦油沥青的四氢呋喃萃取物(THFS)对石油基质沥青进行改性,考察了掺混量、掺混温度和不同种类交联剂对改性沥青性能的影响,确定了THFS最佳掺混量为8%,最佳掺混温度为135℃,甲醛交联剂的最佳掺混量为0.8%,三聚甲醛的最佳掺混量为0.2%。考察了两两和单族组分对基质沥青的改性性能,发现重油(HS)使得改性沥青的针入度、延度增大,沥青烯(A)和甲苯不溶四氢呋喃可溶物(PA)提高感温性,软化点升高。随着醛类交联剂的添加,提高了改性沥青的抗老化性能;甲基(CH_3)、亚甲基(CH_2)透射峰强度逐渐变强,770-730 cm~(-1)、710-690 cm~(-1)和770-810 cm~(-1)苯环取代透射峰强度逐渐增强,1 010~(-1) 270 cm~(-1)处C-O-C伸缩振动峰逐渐增强;热解峰温向高温移动,残炭率增加2%;改性粒子呈现一种连续的流线分布,添加三聚甲醛的改性沥青的流线分布更加集中。     

Applications of cationic gemini surfactant in preparing multi-walled carbon nanotube contained nanofluids

Stable homogeneous nanofluids of multi-walled carbon nanotubes (MWNTs) were prepared by using gemini cationic surfactant trimethylene-1,3-bis (dodecyldimethyl ammonium bromide), abbreviated as 12-3-12,2Br⁻¹, as dispersing agents. Zeta potential and FT-IR measurements were employed to investigate the adsorption mechanism of 12-3-12,2Br⁻¹ on MWNTs. The interactions between MWNTs and 12-3-12,2Br⁻¹ through hydrophobic segments cause hydrophilic MWNT-suspended medium interfaces with high positive charges, which enables the nanofluids to be stable for long periods. At relatively low temperatures the superfluous surfactant molecules form stable layer or column micelles, making an increase in the viscosity of nanofluids. Only 0.6 wt% gemini surfactant was used to obtain 0.5 wt% MWNT dispersions. The dispersions show no MWNTs precipitation for at least 5 weeks.     

煤沥青与石油沥青混合调制道路沥青的研究

采用高效剪切分散仪考察了调配温度、调配时间、搅拌方法等工艺对煤沥青混合石油沥青性能的影响,对优选的样品进行了离析实验、抗老化性能及流变性能评价。结果表明,调配工艺对煤沥青在石油沥青中的分散有重要影响,调配温度的升高、调配时间的延长能促进煤沥青在石油沥青中分散但也会导致调配沥青的老化;煤沥青粒径对调配沥青性能有重要影响,对优选样品的进一步评价表明,调配沥青有好的耐高温流变性能和抗热氧老化性能,储存稳定性可以解决。     

Biomimetic fabrication of hydroxyapatite hollow spheres with polyoxyethylene chain-containing quaternary ammonium salt cationic Gemini surfactant as template

This paper reports a biomimetic fabrication of hydroxyapatite (HAp) with a hollow spherical three-dimensional architecture, using Ca(NO₃)₂ and (NH₄)₃PO₄ as the starting materials, and a polyoxyethylene chain-containing quaternary ammonium salt cationic Gemini surfactant [C₁₂C₂C₁₂ (EO)] as the template. The effects of the surfactant concentration, aging time, and temperature on the morphology and the degree of crystallinity of HAp were investigated. We also proposed a possible mechanism for the formation of hollow spherical HAp. The results showed that the cationic Gemini surfactant was the most important parameter for the formation of spherical HAp. We obtained uniform well-defined hollow spherical HAp with semidiameter about 1.5 μm, using 0.1% mass fraction of template, at 37°C for 7 days.     

化学法改性煤沥青脱除苯并芘的研究

在管式反应器中采用苯甲酸、聚乙二醇、固体古马隆树脂（S）、液体古马隆树脂（L）为添加剂来降低煤沥青中有害物质苯并芘的含量,以期使得煤沥青可绿色化应用。采用紫外-可见分光光度计分析煤沥青中苯并芘含量。考察了反应温度、反应时间、添加剂添加量、催化剂等工艺条件对添加剂脱除煤沥青中苯并芘的影响。结果表明,不同工艺条件能降低煤沥青中苯并芘的含量。在优化条件下,不同添加剂对苯并芘脱除率由高到低依次为：液体古马隆树脂、聚乙二醇、苯甲酸和固体古马隆树脂。分析其反应机理,这与催化剂的酸性相关,发生亲电取代反应。结果表明,液体古马隆树脂（L）在催化剂存在下对煤沥青中苯并芘脱除率可达73.0%,显示了良好的应用前景。     

Rheological and thermo-responsive characteristics of the mixed aqueous solution of gemini cationic surfactant and hydroxyl naphthalene carboxylic acid sodium

The new thermo-switchable wormlike micellar systems were developed by mixing the gemini cationic surfactant, 2-hydroxypropyl-1,3-bis (dimethylmyristylammonium chloride) (14-3(OH)-14(2Cl) and sodium 1-hydroxynaphthalene-2-carboxylate (1SHNC) and sodium 2-hydroxynaphthalene- 3-carboxylate (2SHNC) in a certain concentration range. Their viscoelastic and thermos-responsive behaviors as a function of the salts concentration or temperature were investigated via rheological and cryo-TEM investigations. The results demonstrated that the zero-shear viscosity (η₀) significantly increased while raising salt concentrations above a threshold concentration (C_S*) until reaching maximum and then decreased. For the mixed solutions before the maximum, the zero-shear viscosity linearly decreased with increasing temperature and conformed to the Arrhenius law. However, for those mixed systems displaying thermo-responsive characteristic after the summit, the curve of η₀ as a function of temperature exhibited a maximum over the whole temperature range, namely, the systems showed thermo-thickening and thermo-thinning behaviors at low and high temperatures. The abovementioned phenomena were explained by the formation of hydrogen bond in 14-3(OH)-14(2Cl) molecules and the different solubility of SHNC under different temperatures, and the transition mechanisms of the aggregates were analyzed accordingly.     

Effect of aging time and salt on the viscosity behaviour of a Gemini cationic surfactant

Rheological properties of micellar solutions of a cationic Gemini surfactant, 2-hydroxypropyl-1,3-bis (dodecyldimethylammonium chloride), are studied as a function of aging time and salt addition. The results show that the self-aggregating behaviour in solution changes as a factor of time, probably due to intermolecular hydrogen bonds. The viscosity of the solution undergoes a series of visible changes so that the solution changes from a flow state to highly viscoelastic state, and finally, to a transparent solid, with a corresponding 4–6-fold increase in zero shear state viscosity. Rheology and freeze fracture transmission electron microscopy (FF-TEM) measurements show rod-like micelles at the beginning, which then change to wormlike micelles, and eventually to a quasi-gel-like network. Addition of an inorganic salt (NaCl) induces salting out, while the addition of an organic salt (NaSal) promotes micellar growth. At a fixed NaSal-to-surfactant molar ratio of 3:5, all solutions show Maxwell fluid behaviour and maximum zero-shear-rate viscosity; these trends can be attributed to the formation of a network structure between the cationic ions of the surfactant and Sal^– as the surfactant concentration increases. Crystal analysis further confirms the presence of structures linked by intermolecular hydrogen bonds.     

氢氧化镁-硼酸锌复合阻燃剂辅助制备产率高和电容性能优异的煤焦油沥青基多孔碳

以煤焦油沥青为前驱体,氢氧化镁-硼酸锌复合阻燃剂为助剂,直接在空气条件下高温碳化制备了煤沥青基多孔碳,并探究其电化学性能。得益于阻燃剂的阻燃作用协同其活化、掺杂功能化作用,得到了高产率(55.1%)、多原子(N、B、O)掺杂且具有分级多孔结构的多孔碳。将其作为超级电容器电极材料,在三电极体系中0.5 A·g^-1电流密度下比电容可达344 F·g^-1。此外,以制备的多孔碳和壳聚糖基氨基酸质子盐凝胶电解质组装的柔性对称电容器具有29.3 Wh·kg^-1的高能量密度,在50 000次循环后电容保持率为96.9%,且在-25~75℃温度区间内可正常工作,显示出宽的温度使用范围。     

氢氧化镁-硼酸锌复合阻燃剂辅助制备产率高和电容性能优异的煤焦油沥青基多孔碳

以煤焦油沥青为前驱体,氢氧化镁-硼酸锌复合阻燃剂为助剂,直接在空气条件下高温碳化制备了煤沥青基多孔碳,并探究其电化学性能。得益于阻燃剂的阻燃协同其活化、掺杂功能化作用,得到了高产率(55.1%)、多原子(N、B、O)掺杂且具有分级多孔结构的多孔碳。将其作为超级电容器电极材料,在三电极体系中0.5 A·g^-1电流密度下比电容可达344 F·g^-1。此外,以制备的多孔碳和壳聚糖基氨基酸质子盐凝胶电解质组装的柔性对称电容器具有29.3 Wh·kg^-1的高能量密度,在50 000次循环后电容保持率为96.9%,且在-25~75℃温度区间内可正常工作,显示出宽的温度使用范围。