Kinetic studies of the thermal degradation of cellulose acetate/niobium and chitosan/niobium composites

被引:31
作者
Faria, Elaine A. [1 ]
Prado, Alexandre G. S. [1 ]
机构
[1] Univ Brasilia, Inst Quim, BR-70904970 Brasilia, DF, Brazil
关键词
cellulose; chitosan; niobium; thermal analysis; SEM;
D O I
10.1016/j.reactfunctpolym.2007.04.003
中图分类号
O69 [应用化学];
学科分类号
081704 ;
摘要
Composites based on cellulose acetate/niobium and chitosan/niobium have been obtained by a new synthetic hydrothermal route with different amounts of Nb2O5 (0.0%; 3.7%; 5.8%; 6.7% and 10.9%, incorporated on cellulose acetate fibers and 0.0%; 3.0%; 9.3% and 13.9%, attached on chitosan surface). Thermodecomposition studies were carried on 30-800 degrees C range at rate of 10 degrees C min(-1). Kinetic parameters like activation energy, pre-exponential factor, Gibbs energy, enthalpy and entropy of activation were determined by using Coats-Redfern equation. The activation energy (E) of degradation presented a decreasing with the incorporation of niobium on cellulose acetate, whereas all kinetic parameters maintained constant with the incorporation of niobium, for chitosan what resulted in a more stable that hybrid chitosan/Nb2O5 composites. (c) 2007 Elsevier Ltd. All rights reserved.
引用
收藏
页码:655 / 661
页数:7
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