Polyvinylidene Fluoride
Mostrando 1-12 de 30 artigos, teses e dissertações.
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1. Hot Pressing of Electrospun PVdF-CTFE Membranes as Separators for Lithium Batteries: a Delicate Balance Between Mechanical Properties and Retention
A systematic investigation of the effect of hot-pressing on polyvinylidene fluoride (PVdF) - chlorotrifluoroethylene (CTFE) electrospun membranes, intended as separators and substrate for the electrolyte of lithium batteries, has been carried out by means of dynamic mechanical analysis. Absorption and desorption gravimetric measurements and infrared spectros
Mat. Res.. Publicado em: 11/10/2018
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2. Application of a composite ultrafiltration membrane for biodiesel purification
ABSTRACT This study was carried out to investigate the potentialities of the application of membrane technology in biodiesel purification without need of the decantation step. A new composite UF membrane was prepared from poly(vinylidene fluoride) casting solution (17 wt%) containing a sulfonated Carbon (20 wt%). The assays were performed in a dead-end filtr
Matéria (Rio J.). Publicado em: 19/07/2018
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3. Elastic modulus of PVDF with bentonite or LiNbO3 using deformation energy
Abstract Polyvinylidene fluoride (PVDF) is valued for its properties of transparency to light, lightness, flexibility, mechanical strength, chemical stability, ease of processing, and low-cost production. Ceramics have low mechanical strength and poor processability, but have excellent piezo- and pyroelectric characteristics. The deficiencies of ceramics can
Polímeros. Publicado em: 21/09/2017
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4. MICROFILTRATION AND ULTRAFILTRATION OF Bacillus thuringiensis FERMENTATION BROTH: MEMBRANE PERFORMANCE AND SPORE-CRYSTAL RECOVERY APPROACHES
Abstract Recovery of spores and crystals from the fermentation broth of Bacillus thuringiensis (Bt) was studied using the membrane separation technology. Four types of polymeric membranes, with different characteristics, in the range of microfiltration (MF) and ultrafiltration (UF) were used for evaluating their permeate flux and spore-crystal recovery capac
Braz. J. Chem. Eng.. Publicado em: 2016-12
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5. EFFECT OF POLY (N- VINYPYRROLIDONE) ON THE NON-ISOTHERMAL CRYSTALLIZATION KINETICS AND VISCOELASTIC PROPERTIES OF PVDF FILMS
Abstract Poly(vinylidene fluoride) (PVDF) and PVDF blends with various molecular weights of poly (N- vinylpyrrolidone) (PVP) films were prepared in dimethyl formamide through the solution casting method. Non-isothermal melt crystallization studies of PVDF films were carried out by cooling the molten samples at different temperatures using differential scanni
Braz. J. Chem. Eng.. Publicado em: 2016-12
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6. P(VDF-TrFE)/ZrO2 Polymer-Composites for X-ray Shielding
Poly(vinylidene fluoride – tryfluorethylene) [P(VDF-TrFE)] copolymers were mixed with zirconia nanoparticles. The investigation was conducted with the intention to produce nanocompounds with potential to be used as protective patient shielding in radiological procedures. Polymer based nanocomposites with 1, 2, 3, 5 and 10 wt% of ZrO2 nanoparticles were pre
Mat. Res.. Publicado em: 26/02/2016
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7. Fouling behavior and performance of microfiltration membranes for whey treatment in steady and unsteady-state conditions
Whey pretreatment for protein purification is one of the main applications of cross-flow microfiltration before an ultrafiltration process. In this paper, the effects of the operating pressure and crossflow velocity on the membrane performance and the individual resistances in microfiltration of whey for both unsteady and steady-state conditions were investi
Braz. J. Chem. Eng.. Publicado em: 2014-06
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8. Clay nanoparticles effects on performance and morphology of poly(vinylidene fluoride) membranes
In this study, a comparison between neat poly(vinylidene fluoride) (PVDF) membrane and composite (PVDF-Nanoclay and PVDF-PVP-Nanoclay) membranes is presented. All membranes were synthesized by the phase inversion process, using 18% PVDF, n-methylpyrrolidone as solvent and water as the non-solvent. Demineralized water cross-flow permeation tests were conducte
Braz. J. Chem. Eng.. Publicado em: 2014-03
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9. Ultrafiltration performance of PVDF, PES, and cellulose membranes for the treatment of coconut water (Cocos nucifera L.)
Ultrafiltration (UF) inhibits the enzymatic activity which is responsible for color changes of coconut water without the need for heat treatment. In the present study, UF performance in terms of the permeate flux and enzymatic retention of the coconut water was evaluated at laboratory unit (LU) and pilot unit (PU). The membranes studied were polyethersulfone
Food Sci. Technol. Publicado em: 2013-12
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10. Correlation between morphological properties and ionic conductivity in an electrolyte based on poly(vinylidene fluoride) and poly (2-hydroxyethyl methacrylate)
Materials based on a mixture of poly(vinylidene fluoride) (PVDF), poly(2-hydroxyethyl methacrylate) (PHEMA) and LiClO4 were produced to evaluate their ionic behavior and morphological structure to determine if they can be used as an electrolyte in electrical devices. FTIR chemical analysis results indicated the presence of interactions between PVDF, PHEMA an
Mat. Res.. Publicado em: 27/09/2013
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11. Sulfonation and characterization of styrene-indene copolymers for the development of proton conducting polymer membranes
The aim of this work is to obtain polymer precursors based on styrene copolymers with distinct degrees of sulfonation, as an alternative material for fuel cell membranes. Acetyl sulfate was used to carry out the sulfonation and the performance of the polyelectrolyte was evaluated based on the content of acid polar groups incorporated into the macromolecular
Polímeros. Publicado em: 30/10/2012
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12. Modificação de poli(fluoreto de vinilideno) induzida por radiação gama para aplicação como compósito ionomérico de metal-polímero / Poly(vinylidene fluoride) modification induced by gamma irradiation for application as ionic polymer-metal composite
Gamma-radiation-induced grafting of styrene into poly(vinylidene fluoride) (PVDF) films with 0.125 mm thickness at doses from 1 to 100 kGy in the presence of a styrene/N,N- dimethylformamide (DMF) solution (1:1, v/v) and styrene/toluene (1:1, v/v) at dose rate of 5 kGy h-1 was carried out by simultaneous method under nitrogen atmosphere at room temperature,
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 25/07/2011