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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Cellulose carboxylate/tosylate mixed esters: Synthesis, properties and shaping into microspheres

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Autor(es):
Ferreira, Daniela C. ; Bastos, Gustavo S. ; Pfeifer, Annett ; Heinze, Thomas ; El Seoud, Omar A.
Número total de Autores: 5
Tipo de documento: Artigo Científico
Fonte: Carbohydrate Polymers; v. 152, p. 79-86, NOV 5 2016.
Citações Web of Science: 2
Resumo

Cellulose carboxylate/tosylate mixed esters (Cel-Carboxy/Ts) were synthesized with constant degree of tosylation, DSTs = 0.98 and variable degree of acylation, DScarboxy; acetate, butanoate, and hexanoate. The tosylate (Cel-Ts) was prepared by reacting cellulose with tosyl chloride in presence of trimethylamine. The mixed esters were obtained by reacting Cel-Ts with carboxylic acid anhydride. The dependence of the following on DScarboxy was investigated: IR data, including v(co), v(so) and peak area (-C=0); empirical polarity of the films, determined by an adsorbed perichromic dye. We employed these parameters to determine DScarboxy. Relative to ester saponification, these spectroscopic methods are convenient, expedient, and require much less sample. Mixed esters prepared physically from cellulose tosylate and tosylate/acetate behave only qualitatively similar to (Cel-Carboxy/Ts). The mixed esters were dissolved in acetone and regenerated in water as homogeneous microspheres. (C) 2016 Elsevier Ltd. All rights reserved. (AU)

Processo FAPESP: 14/22136-4 - Uso de solventes verdes e suas misturas na otimização de processos químicos
Beneficiário:Omar Abou El Seoud
Modalidade de apoio: Auxílio à Pesquisa - Temático