THERMAL-BEHAVIOR OF SOME HOMOGENEOUSLY ESTERIFIED PRODUCTS OF HIGH ALPHA-CELLULOSE PULPS OF FAST-GROWING PLANT-SPECIES

High alpha-cellulose pulps obtained from fast growing plant species Le ucaena leucocephala and Hibiscus cannabinus were esterified with trime llitic anhydride (TMA), phthalic anhydride (PTA) and trimethyl acetic anhydride (TMAA), following a homogeneous reaction procedure. The degr ee of substitution achieved was found to vary, up to 2.56, depending o n the reaction conditions. Thermal decomposition was studied by a diff erential thermogravimetry at three heating rates 5, 10 and 20-degrees- C min-1 in static air. The kinetic parameters were evaluated using the generalized equation of Coats and Redfern. The thermal stabilities of the esters were found to vary in the order TMA > PTA > TMAA. The deco mposition process was found to conform to first order weight loss kine tics, and the activation energies of the respective esters at 5-degree s-C min-1 heating rate were 308.11, 194.98 and 213.00 kJ mol-1 respect ively.