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arrangement of individual fibers in the composite. Limitation of hybrid strength is dependent on the failure strain of individual fibers, which is why maximum hybrid strength is obtained when the combining fibers are closely strain compatible [ 25 ]. In

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Abstract  

Hybrid organic–inorganic materials, silica–diol, were synthesized by the sol–gel process from mixtures of tetraethylorthosilicate (TEOS) and diols: ethylene glycol (HO–CH2–CH2–OH) and 1,3 propane diol (HO–CH2–CH2–CH2–OH), in acid catalysis. The gels have been synthesized for a molar ratio H2O:TEOS = 4:1 and different molar ratios diol/TEOS: 0.25; 0.5; 0.75; 1.0; 1.25 and 1.5. The resulting gels were studied by thermal analysis and FT-IR spectroscopy, in order to evidence the interaction of diols with silica matrix. Thermal analysis indicated that the condensation degree increases with the molar ratio diol/TEOS until a certain value. The thermal decomposition of the organic chains bonded within the silica network in the temperature range 250–320 °C, leaded to a silica matrix with modified morphology. The adsorption–desorption isotherms type is different for the samples with and without diol. Thus, the specific surface areas have values <11 m2/g for the samples without diol and >200 m2/g for the samples with diols, depending on the annealing temperature.

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Journal of Thermal Analysis and Calorimetry
Authors: Hieronim Maciejewski, Izabela Dąbek, Ryszard Fiedorow, Michał Dutkiewicz, and Mariusz Majchrzak

meet requirements set by new directions of applications. In recent years, studies on modern hybrid materials of extraordinary and unprecedented properties became one of the most thriving activities in the field of materials chemistry [ 1 – 3 ]. The term

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route is proposed for the preparation of hybrid organic–inorganic nanocomposites based on Fe 2 O 3 and carboxyl terminated PAMAM dendrimers:high pressure hydrothermal method. This procedure is a one-step soft chemical process which consists in in situ

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Introduction Organic–inorganic hybrid materials have gained much attention, which is because that they combine advantages of organic and inorganic materials. Many reports focus on fabrics treated with hybrid materials. Satoh et

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degradation patterns of individual starch derivatives differing in thermal stability. The aim of our work is to characterize the thermal behavior of wheat starch, its sulfate, carboxymethyl and hybrid derivatives as well as the low molecular weight

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Journal of Thermal Analysis and Calorimetry
Authors: Maria J. F. Costa, Antonio S. Araujo, Edjane F. B. Silva, Mirna F. Farias, Valter J. Fernandes Jr., Petrus d’Amorim Santa-Cruz, and José G. A. Pacheco

these limitations, a preparation of new materials was done with the intention of combining high catalytic activity of zeolites with the easier accessibility of mesoporous materials. The proposed hybrid catalyst is composed by aluminosilicate with

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Journal of Thermal Analysis and Calorimetry
Authors: J. J. H. Lancastre, F. M. A. Margaça, L. M. Ferreira, A. N. Falcão, I. M. Miranda Salvado, M. S. M. S. Nabiça, M. H. V. Fernandes, and L. Almásy

-ethyl-ortho-silicate (TEOS) and polydimethylsiloxane (PDMS) have been the focus of attention due to their unique properties such as high flexibility and low elastic modulus together with high mechanical strength [ 6 ]. In these materials, also known as hybrid materials, the

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Abstract  

Fullerene/silica hybrid materials were obtained by radiation grafting on silica surface of toluene or decalin solutions of C60. As determined by thermogravimetric analysis, the amount of C60 grafted on silica surface was dependent from the radiation dose administered and independent from the C60 concentration and the nature of the organic solvent. In absence of air, a dose of 48 kGy was sufficient to ensure a grafting level of 30% by weight of C60 in the hybrid material. The fullerene/silica hybrid material shows a remarkable thermal stability, since the early decomposition starts above 300 °C as measured by DTG and DTA. The chemical structure of the fullerene/silica hybrid material was determined by FT-IR spectroscopy and with solid state 13C CP-MAS NMR. The potential application of such materials has been outlined.

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Abstract  

Hybrid materials were prepared by γ-irradiation of a mixture of polydimethylsiloxane (PDMS), with tetraethylorthosilicate (TEOS) and zirconium propoxide (PrZr), using a 60Co γ source, without any addition of solvents. Thermogravimetry, differential scanning calorimetry and X-ray diffraction measurements showed that the obtained hybrids are amorphous materials of the nanocomposite type. The results highlighted the different influence of each of the metallic alkoxides on the hybrid structure. The material rupture temperature, associated with the degradation of the organic component, depends mainly on the TEOS content, whereas the inorganic component structural stability depends on the relative PrZr content in the alkoxides mixture.

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