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Indian Journal of Chemical Technology (IJCT) >
IJCT Vol.18 [2011] >
IJCT Vol.18(6) [November 2011] >
| Title: | Thermal analysis of cellulose esters prepared from different molecular weight fractions of high  -cellulose pulp |
| Authors: | Tosh, Biranchinarayan |
| Keywords: | Cellulose esters
Coats and Redfern equation
Differential thermogravimetric analysis
Esterification
Fractionation
Regeneration technique
Thermal stability
Thermogravimetric analysis |
| Issue Date: | Nov-2011 |
| Publisher: | NISCAIR-CSIR, India |
| Abstract: | High -cellulose has been dissolved in two
non-degrading solvent systems like dimethyl sulfoxide/paraformaldehyde
(DMSO/PF) and N,N-dimethyl acetamide/lithium chloride (DMAc/LiCl) and then
fractionated to different molecular weight fractions by regeneration technique.
Esters of the different molecular weight fractions of cellulose have been
prepared having substitution chain length of C2-C5 using
pyridine as catalyst. The esters are characterized by IR and 1H-NMR
spectroscopy. Thermal characterization of the esters is done by
thermogravimetric and differential thermogravimetric analysis and the kinetic
parameters of thermal degradation are measured by using Coats and Redfern
equation. It is found that the temperature of active decomposition decreases with
the increase in substitution chain length and also with the decrease in
molecular weight of the fractions. The mechanism of thermal degradation has
also been studied. Cellulose acetate prepared in DMSO/PF solvent system shows
higher temperature of active decomposition (367.5°C) than that prepared in
DMAc/LiCl solvent system (350°C). This is due to the formation of methylol
cellulose ester in DMSO/PF solvent system. |
| Page(s): | 451-457 |
| CC License: |  CC Attribution-Noncommercial-No Derivative Works 2.5 India |
| ISSN: | 0975-0991 (Online); 0971-457X (Print) |
| Source: | IJCT Vol.18(6) [November 2011]
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