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91.
High Charge‐Carrier Mobility of 2.5 cm2 V−1 s−1 from a Water‐Borne Colloid of a Polymeric Semiconductor via Smart Surfactant Engineering 下载免费PDF全文
92.
通过添加表面活性剂制备了Cu-H2O和Zr O2-H2O纳米流体,研究了十二烷基苯磺酸钠、十六烷基三甲基溴化铵和辛基苯基聚氧乙烯醚等表面活性剂对Cu-H2O和Zr O2-H2O纳米流体分散稳定性的影响;并利用分子动力学方法计算出不同表面活性剂分子与Cu/Zr O2颗粒表面的相互作用能。结果发现添加表面活性剂可较大程度地提升纳米流体的稳定性,而尤以添加十二烷基苯磺酸钠的效果最为明显,计算结果也显示十二烷基苯磺酸钠分子与Cu/Zr O2间的吸附作用最强。此外,还模拟了SDBS与Cu-H2O纳米流体中Cu颗粒的吸附行为。 相似文献
93.
Facile fabrication of superhydrophobic polyaniline structures and their anticorrosive properties 下载免费PDF全文
We report a simple approach for the preparation of superhydrophobic polyaniline (PANI) and its application for the corrosion protection coatings. First, PANI was synthesized conventionally by oxidative polymerization with APS. Subsequently, PANI with different wettability was obtained by modification with different surfactants. The surface modification of PANI with three different surfactants (sodium dodecylbenzenesulfonate, polyethylene glycol, and cetyltrimethylammonium bromide) provided excellent surface superhydrophobicity (water contact angle >150°). The structure and morphology of as‐prepared PANI were characterized with Fourier transform infrared, Energy dispersive X‐ray spectroscopy, and Scanning electron microscopy. Corrosion protection performance of PANI with different wettability was evaluated in 3.5% NaCl electrolyte using Tafel polarization curves and electrochemical impedance spectroscopy. The results indicated that various superhydrophobic PANI coatings have better anticorrosion performance as compared to the hydrophilic PANI. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44248. 相似文献
94.
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96.
以3-氨基吡啶和固体光气为原料,一锅法合成中间体1,3-二(3-吡啶基)脲,然后再与溴代十二烷进行季铵化反应,生成了新型的吡啶阳离子Gemini表面活性剂。通过单因素试验法优化了反应条件,得到较佳工艺条件为:n(3-氨基吡啶)∶n(固体光气)=5∶1,二氯甲烷作反应溶剂,反应5h,得到产率为78%的中间体;n(中间体)∶n(溴代十二烷)=1∶10,110℃反应5 h,得到产率为90%的吡啶Gemini表面活性剂。通过FT-IR,~1H NMR,13C NMR和ESI-MS对所得产物的结构进行了表征,并对其表面活性进行了研究。结果表明,该Gemini表面活性剂的临界胶束浓度(cmc)为1.67×10~(-4)mol/L,γcmc为30.7 m N/m。 相似文献
97.
采用荧光分光光度法和Zeta电位法考察了系列Gemini双季铵盐表面活性剂与阴离子表面活性剂十二烷基苯磺酸钠(SDBS)和十二烷基磺酸钠(SDS)的复配效果。结果表明,Gemini双季铵盐表面活性剂疏水链和连接基越长,cmc越小,且疏水链长度对表面活性剂性能的影响较大;Gemini双季铵盐表面活性剂的加入可显著提高阴离子表面活性剂SDBS和SDS的表面活性,当Gemini双季铵盐表面活性剂与SDBS或SDS的摩尔比为3:7时,复配体系的cmc最小,且与SDS复配体系的性能优于与SDBS的复配体系。 相似文献
98.
Conducting polymerized high‐internal‐phase emulsion/single‐walled carbon nanotube nanocomposite foams: Effect of the aqueous‐phase surfactant type on the morphology and conductivity 下载免费PDF全文
Poly(styrene‐co‐divinylbenzene)/single‐walled carbon nanotubes (SWCNTs) polymerized high‐internal‐phase emulsion (polyHIPE) nanocomposite foams were successfully synthesized with various types of aqueous‐phase surfactants. The effects of anionic, cationic, nonionic, and mixed surfactants on the morphology and electrical conductivity of the resulting nanocomposite foams were investigated. The use of an anionic surfactant, sodium dodecylbenzesulfonate (SDBS), did not completely result in the typical polyHIPE nanocomposite foam microstructure because of the partial instability of the high‐internal‐phase emulsion. The nanocomposite foams synthesized by nonionic surfactants, that is, Pluronic F127 and Triton X‐100, and the cationic/anionic mixture, cetyltrimethylammonium bromide/SDBS, exhibited the proper morphology, but the resulting nanocomposite foams were electrically insulators. Interestingly, the use of a Gemini‐like surfactant, sodium dioctylsulfosuccinate (SDOSS), significantly improved both the typical morphology and electrical properties of the resulting nanocomposite foams because of the probable stronger interactions of SDOSS molecules with SWCNTs. The typical morphology of the nanocomposite foam synthesized with the SDOSS/F127 mixed surfactant was significantly improved, but the electrical conductivity decreased to some extent compared with the SDOSS‐synthesized nanocomposite foams. This behavior was attributed to an increase in the tunneling length of the electrons between adjacent SWCNTs. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43883. 相似文献
99.
Synthesis and properties of new water‐soluble copolymers based on methyl acrylic acid sucrose ester and methyl acrylic acid 下载免费PDF全文
The new series of copolymers were obtained based on free radical solution copolymerization by mixing self‐made methyl acrylic acid sucrose ester (MASE) and methyl acrylic acid (MAA) with different ratios. Copolymerization behavior and properties of the new copolymers was investigated with the reaction time, temperature, monomer ratios and characterized by Fourier transform infrared spectra (FT‐IR), carbon nuclear magnetic resonance (13C NMR), and intrinsic viscosity. The results indicated that sucrose was successfully grafted onto poly (methyl acrylic acid). Further, it was demonstrated that low temperature benefited the esterification of MASE. Importantly, the copolymers were founded to have good compatibility with polymethyl methacrylate (PMMA), polytetrafluoroethylene (PTFE), and polyethylene (PE). © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43627. 相似文献
100.
Roza Bouchal Abdellah Hamel Peter Hesemann Martin In Bénédicte Prelot Jerzy Zajac 《International journal of molecular sciences》2016,17(2)
Surface activity and micelle formation of alkylguanidinium chlorides containing 10, 12, 14 and 16 carbon atoms in the hydrophobic tail were studied by combining conductivity and surface tension measurements with isothermal titration calorimetry. The purity of the resulting surfactants, their temperatures of Cr→LC and LC→I transitions, as well as their propensity of forming birefringent phases, were assessed based on the results of 1H and 13C NMR, differential scanning calorimetry (DSC), and polarizing microscopy studies. Whenever possible, the resulting values of Krafft temperature (TK), critical micelle concentration (CMC), minimum surface tension above the CMC, chloride counter-ion binding to the micelle, and the standard enthalpy of micelle formation per mole of surfactant (ΔmicH°) were compared to those characterizing alkyltrimethylammonium chlorides or bromides with the same tail lengths. The value of TK ranged between 292 and 314 K and increased strongly with the increase in the chain length of the hydrophobic tail. Micellization was described as both entropy and enthalpy-driven. Based on the direct calorimetry measurements, the general trends in the CMC with the temperature, hydrophobic tail length, and NaCl addition were found to be similar to those of other types of cationic surfactants. The particularly exothermic character of micellization was ascribed to the hydrogen-binding capacity of the guanidinium head-group. 相似文献