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121.
Tifeng Jiao Yuanyuan Xing Jingxin Zhou Xuefeng Zhu Li Zhang Minghua Liu 《Journal of Dispersion Science and Technology》2013,34(11):1599-1604
Some single chain Schiff bases amphiphiles with different substituted headgroups have been designed and their interfacial phase behaviors and coordination with Cu(II) ions were investigated. It has been found that depending on the size of aromatic headgroups, the formed nanostrucures showed obvious differences, indicating different aggregation behaviors in the Langmuir-Blodgett films. The spreading Cu(II)-coordinated films could be transferred and subsequently characterized by spectral methods and morphological measurement. In addition, during the coordination process of ligand with Cu(II) ions in organized molecular films, some conformational change of long alkyl chains was observed. The present work showed clearly the headgroup effect of amphiphiles on regulating the aggregation behaviors in Langmuir-Blodgett films. 相似文献
122.
PREPARATION AND PHYSICAL PROPERTIES OF BLEND FILMS FROM SODIUM ALGINATE AND POLYACRYLAMIDE SOLUTIONS
《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):1663-1675
Blend films of sodium alginate and polyacrylamide (PAAm) were prepared by mixing the aqueous solution of both samples at a different ratio. All blend films obtained are optically clear to the naked eye. The structure and physical properties of the films were studied by FT-infrared (FT-IR), wide angle X-ray diffraction (WAXD), differential thermal analysis (DTA), thermogravimetic analysis (TGA), scanning electron microscopy (SEM), and tensile strength test. The results showed that the occurrence of interactions between -COO?, -OH groups of sodium alginate and -CONH2 groups of PAAm in the blends through hydrogen formation. The blend films exhibited the higher thermal stability and improved mechanical properties in dry states. These properties had the maximum value around 20 wt% PAAm content in the blend film. The morphological transition of the blend films from sodium alginate-like to PAAm-like was observed by scanning electron microscopy. 相似文献
123.
Y. Peña S. LugoM. Calixto-Rodriguez A. VázquezI. Gómez P. Elizondo 《Applied Surface Science》2011,257(6):2193-2196
In this work, we report the formation of CuInS2 thin films on glass substrates by heating chemically deposited multilayers of copper sulfide (CuS) and indium sulfide (In2S3) at 300 and 350 °C in nitrogen atmosphere at 10 Torr. CIS thin films were prepared by varying the CuS layer thickness in the multilayers with indium sulfide. The XRD analysis showed that the crystallographic structure of the CuInS2 (JCPDS 27-0159) is present on the deposited films. From the optical analysis it was estimated the band gap value for the CIS film (1.49 eV). The electrical conductivity varies from 3 × 10−8 to 3 Ω−1 cm−1 depending on the thickness of the CuS film. CIS films showed p-type conductivity. 相似文献
124.
125.
PLA-ZnO nanocomposite films: Water vapor barrier properties and specific end-use characteristics 总被引:1,自引:0,他引:1
Roberto Pantani Giuliana Gorrasi Giovanni Vigliotta Marius Murariu Philippe Dubois 《European Polymer Journal》2013
PLA nanocomposite films with multifunctional characteristics such as mechanical, anti-UV, antibacterial, electrical, gas barrier properties are potentially of high interest as packaging biomaterials. Occasionally, desired and beneficial effects obtained by addition nanofillers come along with some drawbacks, leading to the sharp drop in the molecular weights of the polyester chains, and consequently an important loss of mechanical and thermal properties. Novel PLA-ZnO nanocomposite films were produced by melt-compounding PLA with 0.5–3% ZnO rod-like nanoparticles. The surface treatment of nanofiller by silanization (with triethoxy caprylylsilane) was necessary to obtain a better dispersion and to limit the decrease of molecular mass of PLA. The morphology, molecular, thermo-mechanical and transport properties to water vapor of PLA-ZnO films were analyzed with respect to the neat PLA. According to DSC and to XRD, the produced films were essentially amorphous. The changes in PLA permeation properties were strongly dependent on temperature and nanofiller loading. The well dispersed ZnO nanoparticles within the polyester matrix were effective in increasing the tortuosity of the diffusive path of the penetrant molecules. The activation energy remained similar for PLA and PLA-1% ZnO, but was found greater at higher loading of ZnO (3%), confirming the increased difficulty of travelling molecules to diffuse through PLA. In comparison to the neat PLA (presenting no antimicrobial efficacy), the nanocomposites were active against both Gram-positive and Gram-negative bacteria, stronger antibacterial activity being evidenced after 7 days elapsed time. By considering the multifunctional properties of PLA-ZnO nanocomposites, the films produced by extrusion can be considered a promising alternative as environmental-friendly packaging materials. 相似文献
126.
Langmuir-Blodgett (LB) films of dialkyldithiophosphate (DDP) modified Cu nanoparticles were prepared. The structure, microfrictional behaviors and adhesion of the LB films were investigated by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and atomic/friction force microscopy (AFM/FFM). Our results showed that the modified Cu nanoparticles have a typical core-shell structure and fine film-forming ability. The images of AFM/FFM showed that LB films of modified Cu nanoparticles were composed of many nanoparticles arranged closely and orderly and the nanoparticles had favorable behaviors of lower friction. The friction loop of the films indicated that the friction force was affected prominently by the surface slope of the Cu nanoparticles and the microfrictional behaviors showed obvious “ratchet effect”. The adhesion experiment showed that the modified Cu nanoparticle had a very small adhesive force. 相似文献
127.
The influence of silicon-containing acrylate as active diluent on the properties of UV-cured epoxydiacrylate films 总被引:3,自引:0,他引:3
A new silicon-containing acrylate, which can be a good active diluent for UV-curable epoxydiacrylate systems, was prepared by reacting N-cyclohexyl-γ-aminopropylmethyldimethoxysilane (CAMS) with trimethylolpropane triacrylate (TMPTA) by Michael-type addition reaction. The reactivity of -NH groups of CAMS with the acrylic groups of TMPTA was characterized by FTIR. The contents of the new active diluent in the UV-cured polymeric films were varied between 5% and 15% by weight. Mechanical, physical, and thermal characterizations of the UV-cured films were investigated: An increase in silicon-containing acrylate content caused a dramatic change of the surface properties of the films, and a decrease in mechanical properties besides the relative elongation. Thermogravimetric analysis of silicon-containing acrylate revealed that incorporating silicon into the structure resulted in a high char yield at 700 °C. Water absorption values of UV-cured films were also affected by the amount of silicon-containing acrylate. 相似文献
128.
This review provides a brief introduction to the Langmuir-Blodgett (LB) technique and to the utilization of ultrathin films in the fields of electronics and optics. The electrical and nonlinear optical properties of the Langmuir-Blodgett monolayer and multilayers of organoruthenium complexes, ferrocene derivatives, metal(4,5-dimercapto-1, 3-dithiol-2-dithiolene)2 complexes, metallophthalocyanines, metalloporphyrins, metal(dibenzotetra-aza[14]annulene)s and siloxane polymers are presented. Possible applications of organometallic LB films in sensors, electroluminescence and electrochromic devices, optical switches, solar cells, infrared detectors and harmonic generators are discussed. 相似文献
129.
T. Takahashi P. Miller Y. M. Chen L. Samuelson D. Galotti B. K. Mandal J. Kumar S. K. Tripathy 《Journal of Polymer Science.Polymer Physics》1993,31(2):165-173
Langmuir-Blodgett (LB) film formation has been investigated for polymers in which non-linear optical (NLO) moieties are attached to the side chain of a polymethacrylate (PMA) backbone. Polymer monolayers were successfully transferred onto hydrophilic glass substrates using a moving-wall type LB trough. The LB films were characterized by pressure-area isotherms, polarized ultraviolet visible spectra, ellipsometry, and second harmonic generation measurements. The characterization shows that NLO moieties in the side chain are inclined at a shallow angle to the plane of the substrate. The second-order nonlinear optical coefficient and molecular hyperpolarizability were also calculated. © 1993 John Wiley & Sons, Inc. 相似文献
130.
Organization of hexadecylaniline (HDA)-modified colloidal gold particles at the air-water interface and the formation thereafter
of lamellar, multilayer films of gold nanoparticles by the Langmuir-Blodgett technique is described in this paper. Formation
of HDA-capped gold nanoparticles is accomplished by a simple biphasic mixture experiment wherein the molecule hexadecylaniline
present in the organic phase leads to electrostatic complexation and reduction of aqueous chloroaurate ions, capping of the
gold nanoparticles thus formed and phase transfer of the now hydrophobic particles into the organic phase. Organization of
gold nanoparticles at the air-water interface is followed by surface pressure—area isotherm measurements while the formation
of multilayer films of the nanoparticles by the Langmuir-Blodgett technique is monitored by quartz crystal microgravimetry,
UV-Vis spectroscopy, Fourier transform infrared spectroscopy and transmission electron microscopy. 相似文献