Sol–gel synthesis of nanosilver embedded hybrid materials using combined organosilica precursors

2012 ◽  
Vol 62 (3) ◽  
pp. 281-286 ◽  
Author(s):  
Shang-Ru Zhai ◽  
Xu Shao ◽  
Di Zhou ◽  
Bin Zhai ◽  
Qing-Da An
2013 ◽  
Vol 749 ◽  
pp. 283-288 ◽  
Author(s):  
Yury Pozhidaev ◽  
Oksana Lebedeva ◽  
Evgenya Sipkina ◽  
Alexandra Chesnokova ◽  
Nikolay Ivanov

Hybrid materials are attractive for a large range of applications from medicine and biotechnology to telecommunication systems and fuel cells. In the present research we have studied sol-gel synthesis of hybrid composites based on carbofunctional organosilicon monomers N,N-bis-(3-triethoxysilylpropyl) thiocarbamide (I) or 2-{[3-(triethoxysilyl) propyamino} pyridine (II), and copolymers of ethylene glycol vinyl glycidyl ether with vinyl chloride.The polymeric materials were characterized by scanning electron microscope (SEM) and IR-spectroscopy. Gel products possess high thermal stability (decomposition temperatures reach 250 °С) and have developed specific surface (to 20 m2g-1).The synthesized composites comprise semi-interpenetrating polymer networks, consisting of three-dimensional and linear polymers that cannot be separated due to the mechanical interlacing of theirs chains. Hybrid composites have a value of sorption capacity for Pt (IV) ions of 70 (I) and 28 (II) mgg-1. Proton conductivity of membranes based on the synthesized composites is characterized by the values 3.52 10-2(I) and 1.19 10-2(II) Scm-1measured at temperature of 25 °C.


2002 ◽  
Vol 726 ◽  
Author(s):  
Maguy Jaber ◽  
Jocelyne Miehe-Brendle ◽  
Ronan Le Dred

AbstractHybrid materials like organo-phyllosilicates exhibit new properties which make them potential candidates for many industrials applications as rubber reinforcement, environmental barriers…. With this aim, a series of new layered inorganic-organic solids, with organic functionalities directly bonded to the inorganic sheets via the Si-C bond, were prepared by a template sol-gel synthesis under soft conditions (room temperature) using octyltriethoxysilane as the silica source, aluminum acetylacetonate as the alumina source, magnesium nitrate and sodium hydroxide. These hybrid materials belong to the 2:1 trioctahedral phyllosilicates family with inorganic compositions close to saponite. The ratio of Al (x) could be varied between 0 and 0.33. The x-ray diffraction patterns agree with a layers structure (presence of the (00l) peak series and the (060) peak). The high d001 spacing values (2.4-2.6 nm) can be related to the octyl chains present in the interlayer space. DRIFT and 13C NMR spectra indicate that the Si-C bonds are intact and siloxanes are fully hydrolyzed giving SiOAl and SiOMg bonds. 27Al and 29Si NMR were carried out in order to determine the repartition of the different elements in the layer: Al substitutes for Si in the tetrahedral layer and for Mg in the octahedral one. These results were determined by elemental analysis. The DTA-TG results show that the organic matter start to decompose in air above 250°C but its complete removal needs temperatures higher then 800°C. The aspect of the materials depends on the value of x; it varies from greasy, waxy, waxy powdery and finally powdery. The hydrophilicity of the solids depends strongly on the aluminum content.


2005 ◽  
Vol 3 (3) ◽  
pp. 452-469 ◽  
Author(s):  
Yordanka Ivanova ◽  
Yanko Dimitriev ◽  
Tsvetelina Gerganova ◽  
Raina Bryaskova ◽  
Maria Fernandes ◽  
...  

AbstractThis work investigates the influence of the precursor trimethylsilil isocyanate on the sol-gel synthesis of hybrid materials. The obtained Si−O−C−N network is additionally modified by titanium and zirconium alcoxypropoxides in the range of 10 to 30 wt. %. The structure of the obtained hybrid materials before and after pyrolysis up to 1100°C was investigated by methods of XRD, FTIR and 29Si MAS NMR. We established that the hybrid structure was stable up to 600°C based on IR study. The structural transformation of the hybrid materials into oxycarbonitrogen system started at 800°C. The network of the hybrids modified by titanium remained stable and amorphous up to the final temperature of the pyrolysis (1100°C) compared to the gels modified by more than 10 wt.% Zr. It was confirmed by XRD analysis that the last mentioned are nanocomposite materials, built from carbooxynitrogen vitreous matrix and ZrO2-nanocrystals (tetragonal). The NMR method verified the presence of heterometallic bonds (Si−O−Ti and Si−O−Zr) and Q4, ZrQ3 or TiQ3, NSiO3 and D structural units in the gels.


1999 ◽  
Vol 22 (3) ◽  
pp. 201-205 ◽  
Author(s):  
J Livage

2019 ◽  
Vol 10 ◽  
pp. 356-362 ◽  
Author(s):  
Yanhui Wang ◽  
P Hubert Mutin ◽  
Johan G Alauzun

Mesoporous TiO2–octylphosphonate hybrid materials were prepared in one step by a nonhydrolytic sol–gel method involving the reaction of Ti(OiPr)4, acetophenone (2 equiv) and diethyl octylphosphonate (from 0 to 0.2 equiv) at 200 °C for 12 hours, in toluene. The different samples were characterized by 31P magic angle spinning nuclear magnetic resonance, Fourier transform infrared spectroscopy, Raman spectroscopy, X-ray diffraction, and nitrogen physisorption. For P/Ti ratios up to 0.1, the hybrid materials can be described as aggregated, roughly spherical, crystalline anatase nanoparticles grafted by octylphosphonate groups via Ti–O–P bonds. The crystallite size decreases with the P/Ti ratio, leading to an increase of the specific surface area and a decrease of the pore size of the hybrid samples. For a P/Ti ratio of 0.2, the volume fraction of organic octyl groups exceeds 50%. The hybrid material becomes nonporous and can be described as amorphous TiO2 clusters modified by octylphosphonate units, where the octyl chains form an organic continuous matrix.


2021 ◽  
Vol 395 (1) ◽  
pp. 2000208
Author(s):  
Alessandra Fusco ◽  
Giovanna Donnarumma ◽  
Pina Caputo ◽  
Monica. Gallo ◽  
Michelina Catauro

2004 ◽  
Vol 24 (6) ◽  
pp. 1371-1374 ◽  
Author(s):  
Petra Egger ◽  
Gian Domenico Sorarù ◽  
Sandra Diré

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