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使用一种简单、新颖的纳米沸石晶体自组装方法, 以γ-氨丙基三甲氧基硅烷(AP-TMS)为偶联剂, 成功地实现了纳米A型沸石粒子在多孔不锈钢、陶瓷以及单晶硅表面的沉积组装, 获得了覆盖度高的续、均匀的沸石粒子层. 组装过程在合成釜内分为载体功能化和晶种化两步. 以该沸石粒子层为晶种二次法成膜, 形成了交织生长的连续、均匀的沸石膜, 并用含少量水的苯甲醛混合液评价了微型膜的渗透蒸发性能, 水-苯甲醛分离系数超过10 000以上. 考察了使用γ-氨丙基三甲氧基硅烷(AP-TMS)、γ-氯丙基三甲氧基硅烷(CP-TMS)和γ-巯丙基三甲氧基硅烷(SP-TMS)三种不同偶联剂时, 纳米A型沸石晶体在多孔不锈钢、陶瓷以及单晶硅表面的自组装效果. 研究发现, 使用CP-TMS作为偶联剂时, 只在不锈钢载体上形成较为连续的粒子层, 而使用SP-TMS作为偶联剂时, 在三种载体上纳米A型沸石粒子均不能沉积形成粒子层. 对偶联剂的作用和粒子组装机制进行了讨论和预测. 相似文献
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通过图案化自组装膜导向的电沉积制备了聚吡咯(PPy)微结构. 由微接触印刷方法制备图案化自组装膜并作为电沉积的模板. 研究发现, 自组装膜在导向电沉积中在不同的基底上具有不同的作用: 在十二烷基硫醇(DDT)、十八烷基硫醇(ODT)修饰的金基底上和十八烷基三氯硅烷(OTS)修饰的铟锡氧化物玻璃上(ITO), 电沉积主要发生在自组装膜未修饰区, 而在半导体单晶硅表面, PPy沉积在OTS修饰区, 是基底表面的导电性及PPy与基底表面基团相容性共同作用的结果. 相似文献
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用3-(甲基丙烯酰氧)丙基三甲氧基硅烷(MPS)、 氨丙基三乙氧硅烷(APTES)和正硅酸乙酯(TEOS)溶胀聚苯乙烯中空微球的壳层, 在壳层表面通过溶胶-凝胶过程, 使亲油和亲水基团通过自组装作用分别朝向聚苯乙烯基体和水相, 形成Janus结构. 用良溶剂N,N-二甲基甲酰胺(DMF)溶解除去聚苯乙烯, 得到二氧化硅基复合Janus纳米材料. 改变反应体系pH值和单体用量等可以调控Janus纳米材料微结构, 得到Janus中空球和纳米片. 相似文献
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以3-异氰酸丙基三乙氧基硅烷和对甲氧基苯胺为原料合成了一种可以自组装形成有机-无机杂化材料的化合物--3-(脲基-4-甲氧基苯基)丙基三乙氧基硅烷. 采用FT-IR, 1H NMR, DSC 和XRD 分析方法对该化合物的结构以及结晶性进行了表征. 将该化合物与聚乙烯醇(PVA)共混, 利用化合物的自组装性质构筑结构均一且致密无孔的离子通道杂化膜, 通过自制的膜运输实验装置测定膜对阳离子的传输性能并提出了相应的传输机制. SEM 照片显示, 自组装杂化膜致密无缺陷, 膜厚度为8 μm. 选择5 种阳离子进行运输实验测试, 结果表明, 自组装杂化离子通道膜对一价的碱金属离子Li+, Na+和K+有很好的传输功能, 这要归功于杂化材料中甲氧基苯基与碱金属阳离子形成的阳离子-π相互作用力. 碱金属阳离子在膜中的扩散过程可由溶解-扩散机制来解释, 结果显示, Li+, Na+和K+在杂化膜中传输的渗透率大小为: PNa+ > PK+ > PLi+ , 说明本研究中的的自组装杂化离子通道膜对Na+有优先选择性. 杂化离子通道膜对二价的Ca2+和Mg2+没有传输作用, 此结果给一二价阳离子的分离带来很好的研究思路. 相似文献
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采用反应离子刻蚀技术在Si(100)表面加工微米级圆柱阵列, 采用自组装技术分别制备了3种硅烷自组装分子膜. 结果表明, 采用反应离子刻蚀构建出的4种微米级圆柱阵列结构规整, 其直径为5 μm, 高度为10 μm, 间距为15~45 μm. 沉积自组装分子膜后, 试样表面的水接触角显著增大, 其中沉积1H,1H,2H,2H-全氟癸基三氯硅烷(FDTS)自组装分子膜接触角最大, 1H,1H,2H,2H-全氟辛烷基三氯硅烷(FOTS)次之, 三氯十八硅烷(OTS)最小. 测得的接触角大于150°时接近Cassie方程计算的接触角, 而小于150°时接近Wenzel方程计算的接触角. 改变圆柱阵列的间距和选择不同的自组装分子膜, 可以控制表面接触角的大小. 原子力显微镜(AFM)观测结果显示, 沉积自组装分子膜可以产生纳米级的团簇. 由微米级圆柱阵列和纳米级自组装分子膜构成的表面结构使Si试样表面接触角最大可达156.0°. 相似文献
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采用半连续种子乳液聚合法, 在十二烷基硫酸钠(SDS)/辛基苯基聚氧乙烯醚(TX-10)复合乳化剂的作用下, 合成了以丙烯酸丁酯(BA)为核, 以甲基丙烯酸甲酯(MMA)、甲基丙烯酸十二氟庚酯(DFHMA)、3-(甲基丙烯酰氧)丙基三甲氧基硅烷(MPTMS)和甲基三甲氧基硅烷(MTMS)为壳的核壳型含氟/硅丙烯酸酯聚合物乳液. 利用FTIR, TEM, SEM-EDX和DSC等手段对乳液组成、乳胶粒子结构、膜表面及断面形态等进行了表征, 讨论了氟/硅含量对聚合物膜性能的影响. 结果表明, 核-壳粒子尺寸为20~30 nm, 乳液膜的性能与膜表面氟和硅的含量及相容性有较大的相关性, 当m(氟)∶m(硅单体)=3∶1时, 形成的膜均匀透明, 吸水率较低, 尺寸稳定性较好. 相似文献
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介孔钛硅分子筛表面功能膜的制备及对水体中铅的去除作用 总被引:4,自引:0,他引:4
研究了制备条件对氯丙基三甲氧基硅烷在水饱和处理的介孔钛硅分子筛表面自组装作用的影响.通过亲核取代反应制备出巯基乙酰氧基功能膜.用XRD、IR、TGA、元素分析、XRF、13CCP/MAS和29SiCP/MASNMR谱对功能膜进行了表征.结果表明,自组装膜的最佳制备条件为选择甲苯作溶剂,控制在110℃加热,硅烷化24h.实验表明,功能膜对水体中的Pb2+离子具有良好的选择吸附能力,可有效地去除水体中的痕量铅 相似文献
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Lucas J. T. Landherr Qing Zhang Claude Cohen Lynden A. Archer 《Journal of Polymer Science.Polymer Physics》2008,46(17):1773-1787
This study focuses on developing dry, surface‐tethered polymeric lubricant coatings capable of significantly decreasing friction and wear of nano‐ and micrometer scale machines. Vinyl‐terminated polydimethylsiloxane chains are spin‐coated with a crosslinking agent and platinum catalyst onto silicon wafers functionalized with a self‐assembling monolayer containing reactive vinyl groups. Lateral force microscopy (LFM) measurements employing a bead probe are used to quantify the coefficient of friction (COF) and adhesion characteristics of the PDMS‐SAM surface tethered networks. The combined polymer network and SAM layer manifest extremely low friction coefficients, μ = 4 × 10?3, which is nearly one order of magnitude lower than the friction coefficient of the bare silicon substrate. The lowest friction forces are measured using silicon substrates covered with nanometer thick, peroxide crosslinked PDMS networks; though poorly crosslinked, these networks display COFs as much as ten‐times lower than a solitary SAM coating layer. Micrometer thick end‐linked optimal networks also manifest attractive interfacial friction properties, with COFs approximately three times larger than the thinner, imperfect networks. These observations are discussed in terms of the structure of the polymer networks and the role of adhesion forces on interfacial friction. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1773–1787, 2008 相似文献
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Self‐assembled silane monolayers: an efficient step‐by‐step recipe for high‐quality,low energy surfaces
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M. Lessel M. Klos H. Hähl R. Fetzer M. Paulus R. Seemann K. Jacobs 《Surface and interface analysis : SIA》2015,47(5):557-564
Organosilane self‐assembled monolayers (SAMs) are commonly used for modifying a wide range of substrates. Depending on the end group, highly hydrophobic or hydrophilic surfaces can be achieved. Silanization bases on the adsorption, self‐assembly and covalent binding of silane molecules onto surfaces and results in a densely packed, SAM. Following wet chemical routines, the quality of the monolayer is often variable and, therefore, unsatisfactory. The process of self‐assembly is not only affected by the chemicals involved and their purity but is also extremely sensitive to ambient parameters such as humidity or temperature and to contaminants. Here, a reliable and efficient wet‐chemical recipe is presented for the preparation of ultra‐smooth, highly ordered alkyl‐terminated silane SAMs on Si wafers. The resulting surfaces are characterized by means of atomic force microscopy, X‐ray reflectometry and contact angle measurements. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Baofeng Cui Ling Zhang Huidi Zhou Junyan Zhang Jianmin Chen 《Surface and interface analysis : SIA》2011,43(11):1377-1381
Self‐assembled poly(amide amine)‐copper (PAMAM/Cu) film on silicon was prepared and investigated by means of contact angle measurement, XPS and atomic force microscopy (AFM). The tribological properties were evaluated using a reciprocal ball‐on‐disc test rig and a lateral force microscope. Results of XPS show the existence of Cu(0) and PAMAM molecule on the surface of the film. Compared with the self‐assembled monolayer of the poly(amide amine) generation 4.0 dendrimer, the friction force of PAMAM/Cu film is lower and the friction coefficient is smaller which can be attributed to the existence of Cu nanoparticles. The PAMAM/Cu film shows a good lubrication effect. The stability of friction and wear resistance of film is improved. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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杂萘联苯聚芳醚腈通过水解、酰化及氨丙基三乙氧基硅烷改性后,合成了侧链含有硅氧烷官能团功能性聚芳醚树脂(PNAS)。采用红外、1H NMR、固体29Si NMR谱等技术手段对产物结构进行表征,用DSC、TGA和原子力显微镜测试了PNAS树脂的性能和自组装薄膜的表面形貌。结果表明,PNAS具有优异的耐热性,其玻璃化转变温度为329 ℃,热失重温度(T5%)达到492 ℃。与短链分子自组装膜比较,PNAS自组装薄膜具有良好的减摩抗磨性能,当载荷为400 mN时,自组装薄膜的稳定摩擦系数达到0.07且在5 h内基本不变。 相似文献
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Dairen Lu Kang Tao Yun Wang Ruke Bai 《Journal of polymer science. Part A, Polymer chemistry》2008,46(23):7667-7676
Supramolecular A2B rod‐coil copolymer, composed of two polystyrene (PSt) arms and one oligo(para‐phenyleneethynylene) (OPE) arm linked via ionic bond, has been designed and successfully synthesized. First, a trifunctional initiator, methyl 1,3‐bis(bromomethyl)benzonate, was prepared and used to initiate the polymerization of styrene under atom transfer radical polymerization (ATRP) condition to provide polystyrene (PSt) carrying monoester group at the middle of polymer chain. Then, the ester group was transferred into tertiary amino group to give amino‐functionalized PSt, (PSt)2? N(CH3)2. Subsequently, the ion‐bonded rod‐coil copolymer, (PSt)2? OPE, was obtained by the reaction of (PSt)2? N(CH3)2 with carboxy‐terminated OPE (OPE? COOH). The resulting copolymer was characterized by nuclear magnetic resonance (NMR), Fourier transformer infrared (FTIR), and gel permeation chromatography (GPC) techniques. Vesicles and spherical micelles were generated from this supramolecular rod‐coil copolymer through the manipulation of the initial polymer concentration in toluene. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7667–7676, 2008 相似文献
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Lee HS Eckmann DM Lee D Hickok NJ Composto RJ 《Langmuir : the ACS journal of surfaces and colloids》2011,27(20):12458-12465
Charged polymer brushes grafted to surfaces are of great interest for antibacterial, biosensor, nanofluidic, and drug delivery applications. In this paper, chitosans with quaternary ammonium salts, CH-Q, were immobilized on silicon oxide and characterized by in situ quartz-crystal microbalance with dissipation, QCM-D, and in situ spectroscopic ellipsometry, SE. Both methods showed that the hydrated film exhibited a minimum thickness of ~40 nm near pH 5 that increased strongly (up to ~80 nm) at lower and higher pH. This symmetric swelling is surprising because CH-Q is a cationic polymer. The CH-Q grafted layer was stable for pH values from 3 to 8 and exhibited rapid, reversible swelling and contraction upon varying pH. The CH-Q layer also reduced S. aureus colonization by a factor of ~30× compared to bare silicon oxide and an amine terminated silane grafted to silicon oxide. This antibacterial characteristic of CH-Q is attributed to the quaternary ammonium salts and the flexible polymer brush. 相似文献
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以对2-溴异丁酸-2′-(对磺苯基)乙酯为引发剂引发苯乙烯发生原子转移自由基聚合,得到的聚合物与NaOH反应转化为端基为磺酸钠的PS(PS-SO3Na).然后采用静电组装方法将PS-SO3Na与表面正离子化的SiO2胶体(SiO2-CBAFS)进行静电组装,得到表面构筑了高分子刷的SiO2胶体/粉体.采用IR、1H-NMR、TG、TEM、AFM、GPC和表面水接触角对组装体系进行结构表征、组装量和部分组装规律研究.结果表明,采用对2-溴异丁酸2′-(对磺苯基)乙酯为引发剂可以制备完全端磺酸基的PS-SO3Na,并且采用静电组装法在SiO2颗粒表面可构筑组装量高达34.4%的高分子刷,有效的提高了高分子刷的组装量;TEM观察下在SiO2胶体颗粒外围可见白色晕圈,PS-SO3Na刷的存在明显改善了SiO2胶体颗粒的分散状态;当样品润洗溶剂由THF变换为H2O时,自组装单层膜的表面水接触角下降幅度小于4°;综合TG、AFM和表面水接触的测试结果发现,用于组装的PS-SO3Na分子量介于1.5×104~3.6×104时,溶液浓度介于2.5×10-5~5×10-5mol/L时,SiO2颗粒具有较好的表面修饰效果. 相似文献
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Christian Rossner Ekaterina B. Zhulina Eugenia Kumacheva 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(27):9370-9375
Using two orthogonal external stimuli, programmable staged surface patterning and self‐assembly of inorganic nanoparticles (NPs) was achieved. For gold NPs capped with end‐grafted poly(styrene‐block‐(4‐vinylbenzoic acid)), P(St‐block‐4VBA), block copolymer ligands, surface‐pinned micelles (patches) formed from NP‐adjacent PSt blocks under reduced solvency conditions (Stimulus 1); solvated NP‐remote P(4VBA) blocks stabilized the NPs against aggregation. Subsequent self‐assembly of patchy NPs was triggered by crosslinking the P(4VBA) blocks with copper(II) ions (Stimulus 2). Block copolymer ligand design has a strong effect on NP self‐assembly. Small, well‐defined clusters assembled from NPs functionalized with ligands with a short P(4VBA) block, while NPs tethered with ligands with a long P(4VBA) block formed large irregularly shaped assemblies. This approach is promising for high‐yield fabrication of colloidal molecules and their assemblies with structural and functional complexity. 相似文献