Cellulose Derivatives
Mostrando 1-12 de 50 artigos, teses e dissertações.
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1. AVALIAÇÃO DO PERFIL DE LIBERAÇÃO DO FÁRMACO IBUPROFENO EM MEMBRANAS SIMÉTRICAS E ASSIMÉTRICAS DE ACETATO DE CELULOSE: EFEITO DA MORFOLOGIA
Cellulose derivatives still receive special attention in today biomedical applications due to their biocompatibility, ability to form resistant membranes and compatibility with various bioactive agents. In this work, cellulose acetate (CA) was used to prepare membranes with different morphologies aiming to evaluate the release profile of the drug ibuprofen (
Quím. Nova. Publicado em: 21/10/2019
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2. Influence of Ionizing Radiation on Biodegradable Foam Trays for Food Packaging Obtained from Irradiated Cassava Starch
ABSTRACT Biodegradable polymers, such as starch, cellulose, and derivatives thereof, are being studied to produce innovative packaging in the most diverse shapes (films, bags, trays, bottles, etc.) to attend this current market trend. The aim of this work was to produce foam trays from cassava starch for food packaging via extrusion followed by thermoforming
Braz. arch. biol. technol.. Publicado em: 29/10/2018
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3. Soil Biodegradation of PLA/CNW Nanocomposites Modified with Ethylene Oxide Derivatives
Due to its ester bonds, poly(lactic acid) (PLA) undergoes biodegradation in humid environments, attracting market attention. The goal of this work was to observe the biodegradation in garden soil of PLA nanocomposites with neat (PLA/CNW) and surfactant modified cellulose nanowhiskers (PLA/CNW/S). Three types of surfactants were tested: poly(ethylene glycol)
Mat. Res.. Publicado em: 01/03/2018
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4. Hydrolysis of cellulose using heteropoly salts derivatives from H3PW12O40 with different redox properties as catalysts
ABSTRACT Heteropoly salts containing different numbers of vanadium atoms (K4[PVW11O40] - KPWV1 and K6[PV3W9O40] - KPWV3) were synthesized from the heteropoly acid H3PW12O40 (HPW), and used as catalysts in hydrolysis of cellulose reactions in order to change the redox properties and verify whether the cluster of catalysts are involved in mechanism reaction. T
Matéria (Rio J.). Publicado em: 10/08/2017
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5. PYROLIGNEOUS LIQUOR PRODUCED FROM ACACIA MEARNSII DE WILD WOOD UNDER CONTROLLED CONDITIONS AS A RENEWABLE SOURCE OF CHEMICALS
Acacia mearnsii de Wild (black wattle) is one of the most important trees planted in Southern Brazil for tannin extraction and charcoal production. The pyrolysis of the black wattle wood used for obtaining charcoal is performed in brick ovens, with the gas fraction being sent directly into the environment. The present study examines the condensable compounds
Quím. Nova. Publicado em: 2015-09
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6. Synthesis and characterization of methylcellulose from cellulose extracted from mango seeds for use as a mortar additive
Methylcellulose was produced from the fibers of Mangifera indica L. Ubá mango seeds. MCD and MCI methylcellulose samples were made by heterogeneous methylation, using dimethyl sulfate and iodomethane as alkylating agents, respectively. The materials produced were characterized for their thermal properties (DSC and TGA), crystallinity (XRD) and Degree of Sub
Polímeros. Publicado em: 14/02/2012
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7. Preparação de blendas de poli(3-hidroxibutirato) com derivados de celulose / Preparation of blends of poly(3-hidroxibutirate) and cellulose derivatives
O poli(3-hidroxibutirato), ou PHB, é um poliéster de grande importância tecnológica por ser biodegradável, proveniente de fontes renováveis e possuir muitas das propriedades típicas de poliésteres derivados do petróleo. No entanto, sua baixa disponibilidade e seu perfil de cristalização fazem com que o polímero ainda apresente muitos desafios par
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 11/07/2011
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8. Aplicações da celulose de palha de cana-de-açúcar: obtenção de derivados partindo de celulose branqueada e de biocompósitos com poliuretana obtida a partir de óleo de mamona (Ricinus communis L.) / Applications of sugarcane straw cellulose: obtainment of derivatives from bleached cellulose and biocomposites with polyurethane obtained from castor oil (Ricinus communis L.)
The sugarcane processing generates various agricultural byproducts such as bagasse and straw, which is considered one of the main waste generated due to the mechanization of the harvest in Brazil. Thus, the availability and composition of sugarcane straw have driven a great effort to develop technologies that provide its effective utilization. This study aim
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 11/04/2011
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9. Studies on anionic surfactant structure in the aggregation with (hydroxypropyl)cellulose
Abstract: Fluorescence probing, viscosity and light scattering measurements have been combined to study the aggregation of different anionic surfactants mainly in dilute solutions (0.5% w/v) of (hydroxypropyl)cellulose (HPC MW 173,000), in moderate ionic strength (NaCl 0.1 mol.L-1). The set of surfactants includes natural cholesterol derivatives, sodium chol
Publicado em: 2010
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10. Modificações da Celulose Kraft Branqueada de Eucalipto por Tratamento Térmico e de Radiação Ultravioleta
Cellulose is used like raw material on many products, it may be found in native form (cellulose I) or on its modified forms (cellulose II, III1, III2, IV1, and IV2). Cellulose is obtained by many processes and raw materials being, alkaline pulping of woods (hardwood/softwood) is most frequent. In time function cellulose products are modified since hydrolysis
Publicado em: 2009
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11. CELLULOSE SUBSTRATE ROOM-TEMPERATURE PHOSPHORIMETRY FOR THE DETERMINATION OF 2 METHYL INDOL E 7 METHYL INDOL: METHOD DEVELOPMENT, VALIDATION AND CRITICAL EVALUATION OF THE APPLICABILITY OF THE TECHNIQUE / FOSFORIMETRIA EM TEMPERATURA AMBIENTE EM SUBSTRATO DE CELULOSE PARA A DETERMINAÇÃO DE 2 METIL INDOL E 7 METIL INDOL: DESENVOLVIMENTO DE MÉTODO, VALIDAÇÃO E AVALIAÇÃO CRÍTICA DA APLICABILIDADE DA TÉCNICA
In this work, room-temperature phosphorimetry using cellulose substrates was evaluated as analytical technique for the determination of two indol derivatives (2 methyl indol and 7 methyl indol). The phosphorescence from both analytes were studied in a univaried way in function of several experimental parameters such as the phosphorescence decay rate; type an
Publicado em: 2008
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12. Sintese e Caracterização de Derivados da Celulose Modificada com Anidridos Orgânicos : adsorção e Termodinamica de Interação com Cations Metalicos / Synthesis and characterization of cellulose derivatives with organic anhydrides : adsorption and interation thermodynamic metallic cations
Cellulose is a widely available biopolymer in nature and its draws considerable chemical interest due its various useful applications. The polysaccharide modification is primarily based on their hydroxyl group reactivity, which determines the carbohydrate chemistry and their related structures. The chemical modification of cellulose was carried out in a solv
Publicado em: 2007