Processo Para Obtenção De Compósitos Cerâmicos A Partir De Polìmeros Polissilanos Ou Polissiloxanos, Reforço De Fibras De Poliacrilonitrila, De Celulose, De Hìbridos De Fibras De Poliacrilonitrila E De Celulose, De Fibras De Carbono, De Hìbridos De Fibras De Carbono E De Poliacrilonitrila, E Fibras De Carbono E De Celulose

Processo para obtenção de compósitos cerâmicos a partir de polímeros polissilanos ou polissiloxanos, reforço de fibras de poliacrilonitrila, de celulose, de híbridos de fibras de poliacrilonitrila e de celulose, de fibras de carbono, de híbridos de fibras de carbono e de poliacrilonitrila, e fibras de carbono e de celulose, que permite a obtenção de materiais que podem ter aplicações em componentes estruturais ou não, em contato com áreas quentes onde o requisito essencial é resistência termomecânica e de desgaste erosivo, dito processo sendo particularmente definido pelo fato de envolver a manufatura de compósitos cerâmicos tendo como matriz impregnante polímeros contendo silício precursores de carbeto de silício ou de oxicarbeto de silício e reforço a base de fibras de poliacrilonitrila (PAN), ou fibras de celulose (rayon), ou híbridos de fibras de poliacrilonitrila e de celulose, ou fibras de carbono, ou híbridos de fibras de carbono e de poliacrilonitrila, ou híbridos de fibras de carbono e de celulose, dispostas na forma de preformas ou pré-impregnados.BR9901922 (A)C04B35/00C08L83/04C04B35/00C08L83/04BR19999901922C04B35/00C08L83/04C04B35/00C08L83/0

Suporte Monolìtico Contendo Tio2 Imobilizado E Processo De Produção Do Mesmo

SUPORTE MONOLÍTICO CONTENDO TI02 IMOBILIZADO E PROCESSO DE PRODUÇÃO DO MESMO A presente invenção trata-se de TIO2 (dióxido de titânio) imobilizado em suporte monolítico, denominado suporte monolítico imobilizado com TIO2. A imobilização de TIO2 ocorre em uma matriz de silicona porosa, moldável, com alta área superficial e um grande número de sítios ativos disponíveis de TIO2 para as reações de fotodegradação de substâncias orgânicas e inorgânicas, O suporte monolítico imobilizado com TIO2 é de simples reprodução em formas e tamanhos desejados, para a utilização em fotocatálise heterogênea em tratamento de água e efluentes.BRPI0905411 (A2)B01J37/04B01J21/06B01J31/06BR2009PI05411B01J37/04B01J21/06B01J31/0

Novel Electrochemical Sensor For The Selective Recognition Of Chlorogenic Acid.

In this study, a novel sensitive molecularly imprinted electrochemical sensor was constructed for the selective detection of chlorogenic acid (CGA) by deposition of a molecularly imprinted siloxane (MIS) film, prepared by sol-gel process, onto Au bare electrode surface. Initially, a (3-mercaptopropyl)siloxane layer (MSL) was formed on the Au bare surface, followed by a siloxane layer obtained from the acid-catalyzed hydrolysis/condensation of a solution constituted by tetraethoxysilane (TEOS), phenyltriethoxysilane (PTEOS), 3-(aminopropyl)trimethoxysilane (APTMS) and CGA, as a molecular template. After the GCA extraction the MIS imprinted film was electrochemically characterized using differential pulse voltammetry (DPV). The MIS/Au sensor was tested in a solution of the CGA template and other similar molecules. This electrode displayed excellent selectivity towards CGA when compared with structurally similar molecules. Under optimized experimental conditions, the peak current response of the sensor for CGA was linear from 5.0 × 10(-7)mol L(-1) to 1.4 × 10(-5)mol L(-1), and the detection limit was 1.48 × 10(-7)mol L(-1). The MIS/Au sensor was successfully applied for the determination of CGA in coffee and tea samples.69544-5

Surface Modification Of Pdms Microchips With Poly(ethylene Glycol) Derivatives For μtas Applications.

In this work is presented a method for the modification of native PDMS surface in order to improve its applicability as a substrate for microfluidic devices, especially in the analysis of nonpolar analytes. Therefore, poly(ethylene glycol) divinyl ether modified PDMS substrate was obtained by surface modification of native PDMS. The modified substrate was characterized by attenuated total reflectance infrared spectroscopy, water contact angle measurements, and by evaluating the adsorption of rhodamine B and the magnitude of the EOF mobility. The reaction was confirmed by the spectroscopic evaluation. The formation of a well-spread water film over the surface immediately after the modification was an indicative of the modified surface hydrophilicity. This characteristic was maintained for approximately ten days, with a gradual return to a hydrophobic state. Fluorescence assays showed that the nonpolar adsorption property of PDMS was significantly decreased. The EOF mobility obtained was 3.6 × 10(-4) cm(2) V(-1) s(-1) , higher than the typical values found for native PDMS. Due to the better wettability promoted by the modification, the filling of the microchannels with aqueous solutions was facilitated and trapping of air bubbles was not observed.352346-5

Biomaterial De Quitosana E Hidroxiapatita (cnhap) Para Preenchimento ósseo E Processo Para Produção Do Mesmo

Resumo não disponível.BRPI0905514 (A2)A61L27/12A61L27/20A61L27/52BR2009PI05514A61L27/12A61L27/20A61L27/5

Raman Imaging Spectroscopic Characterization Of Modified Poly(dimethylsiloxane) For Micro Total Analysis Systems Applications.

Methacryloxypropyl-modified poly(dimethylsiloxane) rubbers were obtained from poly(dimethylsiloxane), PDMS, and methacryloxypropyltrimethoxysilane, MPTMS, by polycondensation reactions. The modified rubbers, prepared with 20 and 30% (v/v) of MPTMS, were used as substrates for microchannel fabrication by the CO(2) laser ablation technique. Raman imaging spectroscopy was used for the surface characterization, showing the homogeneity of the rubbery material, with uniform distribution of the crosslinking centers. Under the experimental conditions used, damage to the rubber from the CO(2) laser radiation used for the channel engraving was not observed. Correlation maps of the surface were obtained in order to spatially evaluate the modification inside and outside the channels. The correlations between the methacryloxypropyl-modified poly(dimethylsiloxane) rubbers and MPTMS (spectral range of 1800-1550 cm(-1)) and PDMS (spectral range of 820-670 cm(-1)) precursors were higher than 0.95 and 0.99, respectively. In addition, Raman imaging spectroscopy allows monitoring the topography of the fabricated microchannel.10067-7

Synthesis and Characterization of Semi-Interpenetrating Networks Based on Poly(dimethylsiloxane) and Poly(vinyl alcohol)

Semi-interpenetrating networks (Semi-IPNs) with different compositions were prepared from poly(dimethylsiloxane) (PDMS), tetraethylorthosilicate (TEOS), and poly (vinyl alcohol) (PVA) by the sol-gel process in this study. The characterization of the PDMS/PVA semi-IPN was carried out using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and swelling measurements. The presence of PVA domains dispersed in the PDMS network disrupted the network and allowed PDMS to crystallize, as observed by the crystallization and melting peaks in the DSC analyses. Because of the presence of hydrophilic (-OH) and hydrophobic (Si-(CH(3))(2)) domains, there was an appropriate hydrophylic/hydrophobic balance in the semi-IPNs prepared, which led to a maximum equilibrium water content of similar to 14 wt % without a loss in the ability to swell less polar solvents. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 115: 158-166, 2010FAPEMIGCNPqCAPE