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《化学研究与应用》2021,33(9)
以1,4-环己二醇、氯乙酰氯、长链叔胺(RN(CH_3)_2,R=10、12、14、16)为原料,合成了一系列不同长度烷基链的双酯基型Gemini表面活性剂(分别命名为C10-EG-10、C12-EG-C12、C14-EG-C14、C16-EG-C16),用FTIR、NMR(~1H、~(13)C)对中间体及产物进行了表征,并研究了表面活性剂的表面性能及抑菌能力。结果表明:在298.15K时,采用铂金环法测定了合成的4种不同长度烷基链Gemini表面活性剂的临界胶束浓度,C10-EG-C10、C12-EG-C12、C14-EG-C14、C16-EG-C16的CMC值分别为5.495、1.096、0.186、0.045 mmol·L~(-1),与传统单链季铵盐表面活性剂相比,合成的Gemini表面活性剂具有较低的CMC值。胶束化热力学参数结果表明在形成胶束过程中是自发放热的。对合成的4种表面活性剂进行了乳化性能、起泡性能和抑菌测试,C14-EG-C14表面活性剂具有很好的乳化能力;C16-EG-C16 Gemini表面活性剂具有良好的稳泡能力;C10-EG-C10表面活性剂具有良好的抑菌能力。 相似文献
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碳氟-碳氢表面活性剂混合水溶液在油面上铺展 总被引:9,自引:0,他引:9
本文研究RfCONH(CH2)3N(C2H5)2CH3I/CnH2n 1,COONa及RfCOONa/CmH2m 1N(CH3)3Br(Rf=F[CF(CF3)CF2O]2CF(CF3);n=7,8.11,13;m=8,10,12)两类正,负离子碳氟-碳氢表面活性剂混合水溶液在油面上的铺展及对油面的密封性能。研究表明在碳氟表面活性剂中加入异电性碳氢表面活性剂可大大降低碳氟表面活性剂水溶液的铺展浓度,也可使一些因素表面张力较高而不能铺展的碳氟表面活性剂水溶液在油面上铺展。在碳氟表面活性剂中加入异电性碳氢表面活性剂可提高水膜对油面的密封性。若在混合表面活性剂中加入黄原胶,水膜的密封性能更好。 相似文献
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混合阴阳离子表面活性剂体系的物理化学性质 总被引:4,自引:0,他引:4
测定并比较了TX-100(C_8ΦE_(9.8))及TX-100的硫酸盐(_8CΦE_(9.8)S)分别与阳离子表面活性剂(C_nPy, n=10, 12, 14; C_mNM_3, m=16, 18)混合后, 混合表面活性剂的表面活性、水溶液的稳定性、起泡能力和泡沫稳定性等物理化学性质。 相似文献
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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
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用C10~C16脂肪醇与2-氯-2-氧-1,3,2-二氧磷杂环戊烷低温反应生成环状磷酸酯的中间产物,再用N,N-二甲基十二胺在亲核溶剂中65℃下开环反应合成了4种含N 和磷酸根阴离子的两性孪联表面活性剂C10-C12、C12-C12、C14-C12和C16-C12,其质量收率分别为32%、54%、18%和28%。产物的结构通过1HNMR和元素组成分析,表明两性离子表面活性剂C、H、O、N的分析值与理论计算值偏差不超过0.3%。四种表面活性剂的临界胶束浓度(cmc)在0.0072~0.0125mmol/L之间,临界胶束浓度时表面张力(γcmc)依次为23.90、25.61、27.68和36.08mN/m。其中,C10-C12、C12-C12和C14-C12有较好的界面活性,加入盐可以使表面活性剂与烷烃间的界面张力下降,但下降程度有限,不能达到超低界面张力(10-3mN/m)。 相似文献
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正负离子表面活性剂与两性表面活性剂的相互作用 总被引:3,自引:0,他引:3
本文研究正负离子表面活性剂与两性表面活性剂混合水溶液的表面性质, 以及两性表面活性剂对正负离子裘面活性剂溶解度的影响。结果表明: (1) 两性表面活性剂的加溶作用,有助于正负离子表面活性剂的溶解; (2) 加入两性表面活性剂的量适当, 混合溶液基本保持原正负离子表面活性剂的表面活性; (3) 正负离子表面活性剂与两性表面活性剂在表面层和胶团中分子间的相互作用比正负离子表面活性剂与非离子表面活性剂分子间的相互作用稍强HC-FC正负; 离子表面活性剂与两性表面活性剂混合体系在表面层中有可能形成双分子或多分子层结构。 相似文献
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以水玻璃为硅源,在pH=3以下合成MSU-X介孔材料的报道很少,本文将pH范围扩展至0.78,并从廉价的水玻璃和工业级非离子表面活性剂AEO-9出发,用二步法合成出介孔分子筛MSU-1。首先将无机前驱体和非离子表面活性剂在介稳态下(pH≈2,t≈2 ℃)混合,然后调pH至所需值(0.78~3.94),在该pH值下进行二氧化硅缩聚。合成出的MSU-1具有孔分布窄,短程有序度提高,颗粒呈微米级等特点。其中在pH=1.98下合成的MSU-1具有最薄的孔壁、最大的比表面和孔容;在pH=0.78下合成的MSU-1具有最厚的孔壁、最大的孔径和d100值。随着pH值的增大,孔壁厚度先减小后增大。 相似文献
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Li F Wang Z Ergang NS Fyfe CA Stein A 《Langmuir : the ACS journal of surfaces and colloids》2007,23(7):3996-4004
Monolithic pieces of hierarchically structured silica, containing both periodic macropores and mesopores with well-controlled architecture, are synthesized by dual templating methods. Colloidal crystal templating with close-packed arrays of poly(methyl methacrylate) spheres yields regular, highly interconnected macropores a few hundred nanometers in diameter, and templating with nonionic surfactants produces mesoporosity (2.5-5.1 nm pore diameters) in the macropore walls. Several distinct mesostructures can be achieved within the silica skeleton, depending on the choice of surfactant, co-surfactant, and processing conditions. In the three-dimensional (3D) confinement of the colloidal crystal template, wormlike channels, cubic (Pm3n), or two-dimensional (2D) hexagonal (P6mm) mesostructures are produced with the surfactant Brij 56 (C16H33(OCH2CH2)nOH (n approximately 10) and dodecane as cosurfactant. In the 2D hexagonal structure, channels are oriented perpendicular to the polymer spheres, thereby connecting adjacent macropores through the silica walls. This orientation contrasts with channel alignment parallel to latex spheres when the polymeric surfactant Pluronic P123 (EO20PO70EO20) is used. On the basis of high-resolution 3D transmission electron microscopy, scanning electron microscopy, small-angle X-ray scattering, and nitrogen sorption measurements, structural and textural properties of the monoliths are described in detail as a function of the synthesis parameters. The control over the mesoarchitecture of these silica-surfactant systems in 3D confinement is explained by considering the relative dimensions of the mesostructures with respect to the interstitial space in the latex template, interfacial interactions, entropic effects, and structural frustration. 相似文献
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High-temperature synthesis of stable ordered mesoporous silica materials by using fluorocarbon-hydrocarbon surfactant mixtures 总被引:3,自引:0,他引:3
Li D Han Y Song J Zhao L Xu X Di Y Xiao FS 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(23):5911-5922
Highly ordered hexagonal mesoporous silica materials (JLU-20) with uniform pore sizes have been successfully synthesized at high temperature (150-220 degrees C) by using fluorocarbon-hydrocarbon surfactant mixtures. The fluorocarbon-hydrocarbon surfactant mixtures combine the advantages of both stable fluorocarbon surfactants and ordered hydrocarbon surfactants, giving ordered and stable mixed micelles at high temperature (150-220 degrees C). Mesoporous JLU-20 shows extraordinary stability towards hydrothermal treatment (100 % steam at 800 degrees C for 2 h or boiling water for 80 h), thermal treatment (calcination at 1000 degrees C for 4 h), and toward mechanical treatment (compressed at 740 MPa). Transmission electron microscopy images of JLU-20 show well-ordered hexagonal arrays of mesopores with one-dimensional (1D) channels and further confirm that JLU-20 has a two-dimensional (2D) hexagonal (P6 mm) mesostructure. 29Si HR MAS NMR spectra of as-synthesized JLU-20 shows that JLU-20 is primarily made up of fully condensed Q4 silica units (delta=-112 ppm) with a small contribution from incompletely cross-linked Q3 (delta=-102 ppm) as deduced from the very high Q4/Q3 ratio of 6.5, indicating that the mesoporous walls of JLU-20 are fully condensed. Such unique structural features should be directly attributed to the high-temperature synthesis, which is responsible for the observed high thermal, hydrothermal, and mechanical stability of the mesoporous silica materials with well-ordered hexagonal symmetry. Furthermore, the concept of "high-temperature synthesis" is successfully extended to the preparation of three-dimensional (3D) cubic mesoporous silica materials by the assistance of a fluorocarbon surfactant as a co-template. The obtained material, designated JLU-21, has a well-ordered cubic Im3m mesostructure with fully condensed pore walls and shows unusually high hydrothermal stability, as compared with conventional cubic mesoporous silica materials such as SBA-16. 相似文献
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以LiOH·H2O, NH4VO3, NH4H2PO4 和麦芽糖等为原料, 采用水热法合成了碳包覆的磷酸钒锂化合物, 考察了碳含量对材料电化学性能的影响. 利用XRD, TEM, SEM和恒流充放电测试等手段对产物的结构、 形貌和电化学性能进行表征. 结果表明, 在650℃煅烧的样品为单一纯相的单斜晶体结构. 晶体颗粒分布为100~300 nm, 粒度分散均匀, 分散性良好, 无团聚现象, 且在颗粒表面包覆了一层无定形碳, 这有利于改善材料的导电率. 含碳量为10.23%的样品, 在倍率1.0C的电流密度下, 在3.0~4.3 V电压范围内, 样品的首次放电比容量高达118.8 mA·h/g, 循环15圈后放电比容量为115.1 mA·h/g, 容量保持率为96.88%. 相似文献
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以离子液体为结构导向剂合成有序超微孔二氧化硅 总被引:1,自引:0,他引:1
在酸性条件下, 以1-十六烷基-3-甲基溴化咪唑为表面活性剂合成了具有有序超微孔结构的二氧化硅材料, 所合成的材料具有较高的比表面积和二维六方有序的孔结构, 样品的孔径尺寸为1.8 nm. 相似文献
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Preparation and Optical Characterization of Sol-Gel Deposited Pb(Zr0.45Ti0.55)O3 Films 总被引:3,自引:0,他引:3
Homogeneous crack-free lead zirconate titanate (Pb(Zr0.45Ti0.55)O3: PZT 45/55) films were prepared by a chemically modified sol-gel process using lead acetate trihydrate, zirconium n-propoxide, and titanium isopropoxide precursors. The coating solutions were modified by the addition of diethanolamine. Single and multilayer films were deposited with a 2000 rpm spin rate on fused silica and MgO(100) substrates. Multiple spin coating with an intermediate heat treatment in air at 400°C for 3 min between coatings was performed to obtain films up to 2 m in thickness. The formation of the tetragonal perovskite structure was found to depend on the intermediate firing temperature, final annealing temperature, and annealing time. A 650°C rapid thermal annealing treatment in oxygen was required to crystallize the PZT film into the perovskite structure. The films were characterized using optical spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and thermo-gravimetry and differential scanning calorimetry (TG-DSC). The optical constants of the PZT films were evaluated from spectral transmittance and reflectance measurements. Optical constants are presented over the visible and near infrared region. 相似文献
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Fe3O4 nanorods and Fe2O3 nanowires have been synthesized through a simple thermal oxide reaction of Fe with C2H2O4 solution at 200–600°C for 1 h in the air. The morphology and structure of Fe3O4 nanorods and Fe2O3 nanowires were detected with powder X-ray diffraction, scanning electron microscopy and transmission electron microscopy.
The influence of temperature on the morphology development was experimentally investigated. The results show that the polycrystals
Fe3O4 nanorods with cubic structure and the average diameter of 0.5–0.8 μm grow after reaction at 200–500°C for 1 h in the air.
When the temperature was 600°C, the samples completely became Fe2O3 nanowires with hexagonal structure. It was found that C2H2O4 molecules had a significant effect on the formation of Fe3O4 nanorods. A possible mechanism was also proposed to account for the growth of these Fe3O4 nanorods.
Supported by the Fund of Weinan Teacher’s University (Grant No. 08YKZ008), the National Natural Science Foundation of China
(Grant No. 20573072) and the Doctoral Fund of Ministry of Education of China (Grant No. 20060718010) 相似文献
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The new mixed oxide having composition close to Ca7Co3Ga5O18 was synthesized from CaCO3, Co3O4 and Ga2O3 at 1150 °C in air and studied by neutron and synchrotron X-ray powder diffraction, selected-area electron diffraction and high-resolution electron microscopy. The structure was refined, using time-of-flight (TOF) neutron powder diffraction data, in space group F432, with and Z=8, to RF=0.7%. It is considerably disordered, with four different tetrahedral sites randomly occupied by Co and Ga atoms at a ratio of 1:2. The tetrahedra form a disordered (Co1/3Ga2/3)O2 3D-framework inside which isolated CoO6 octahedra, surrounded by 8 Ca atoms, are located. The structure is related to the ordered structure of Ca14Al10Zn6O35. Electron diffraction patterns confirmed the symmetry and unit cell and revealed no diffuse scattering. High-resolution electron microscopy images showed the absence of extended structural defects. 相似文献
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Mixed surfactant systems have the potential to impart controlled combinations of functionality and pore structure to mesoporous metal oxides. Here, we combine a functional glucopyranoside surfactant with a cationic surfactant that readily forms liquid crystalline mesophases. The phase diagram for the ternary system CTAB/H(2)O/n-octyl-beta-D-glucopyranoside (C(8)G(1)) at 50 degrees C is measured using polarized optical microscopy. At this temperature, the binary C(8)G(1)/H(2)O system forms disordered micellar solutions up to 72 wt% C(8)G(1), and there is no hexagonal phase. With the addition of CTAB, we identify a large area of hexagonal phase, as well as cubic, lamellar and solid surfactant phases. The ternary phase diagram is used to predict the synthesis of thick mesoporous silica films via a direct liquid crystal templating technique. By changing the relative concentration of mixed surfactants as well as inorganic precursor species, surfactant/silica mesostructured thick films can be synthesized with variable glucopyranoside content, and with 2D hexagonal, cubic and lamellar structures. The domains over which different mesophases are prepared correspond well with those of the ternary phase diagram if the hydrophilic inorganic species is assumed to act as an equivalent volume of water. 相似文献
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通过蒸汽诱导内部水解法(VIH)在介孔分子筛SBA-15孔壁上引入Al_2O_3,合成得到Al_2O_3@SBA-15复合物,随后与对二苯甲酸配体反应,从而制备得到金属有机框架化合物(MIL-53)与介孔分子筛(SBA-15)复合材料(MIL-53@SBA-15)。采用粉末X射线衍射(PXRD)、N_2吸附-脱附测试、扫描电子显微镜(SEM)和透射电子显微镜(TEM)等技术证明成功合成了MIL-53@SBA-15复合材料。染料吸附实验结果表明,MIL-53@SBA-15复合材料相比于SBA-15、MIL-53及其物理混合样品,表现出对丁基罗丹明染料更高效吸附特性。 相似文献
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Yan Wang Jisen Zhang Jishuang Zhang Peifen Zhu Guofeng Wang 《Journal of solid state chemistry》2007,180(8):2268-2272
Water-soluble PVP-stabilized hexagonal-phase La0.78Yb0.20Er0.02F3 nanocrystals (NCs) were synthesized by hydrothermal method. The NCs were coated with a very thin silica shell, and amino groups were introduced to the surface of silica shells by copolymerization of 3-aminopropyl(triethoxy)silane. The core/shell NCs can be dispersed in ethanol and water to form stable colloidal solution. The transmission electron microscopy (TEM), selected area electron diffraction (SAED), powder X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR) were used to characterize the core/shell materials. In addition, the green up-conversion fluorescence mechanism of La0.78Yb0.20Er0.02F3/SiO2 NCs was studied with a 980-nm diode laser as excitation source. The water solubility, small core/shell particles size, and well colloidal stability mean the green up-conversion fluorescence NCs have potential applications in bioassay. 相似文献