Studies upon the synthesis of cellulose stearate under microwave heating

The possibility of obtaining cellulose stearate by transesterification of methylstearate with low-molecular microcrystalline cellulose under microwave heating was studied. The influence of different parameters such as the molar ratio of the initial substances, quantity of catalyst, duration of reactions and power of the microwave heating upon the degree of esterification were established. The suitable conditions for carrying out transesterification under microwave heating are: molar ratio (cellulose: methylstearate)=1:3, catalyst quantity 0.25x10(-2) Mol p-toluene sulphonic acid per mol cellulose, 600 W-power of the microwave heating and the reaction time-10 min. The resultant cellulose stearate containing 65% combined stearic acid and 0.95 degree of substitution of hydroxyl groups. The influence of the reaction time, the temperature and the quantity of methylstearate upon the degree of destruction of cellulose under microwave heating was studied. The destruction of microcrystalline cellulose under these conditions is described by an equation of the second order. (C) 2004 Elsevier Ltd. All rights reserved.