A study of the reactivity of sodium ions in etherification reaction of cellulose

Abstract

The reactivity of sodium ions in etherification reaction of cellulose was studied and the experiments were conducted under various reaction conditions. Sodium chloroacetate immediately obtained from the reaction of sodium hydroxide and monochloroacetic acid, was used as etherifying agent. The extent of the reactivity of sodium ions was studied at various tem.peratures, reaction times and reaction media. In this work, the laboratory experiments were conducted at 26 + 2°C and at 44 + 2°C for 1, 3, 5 and 7 days and by using non-polar (benzene, toluene, n-hexane and cyclohexane) and polar organic solvents (methyl ethyl ketone, acetone, iso-propyl alcohol, n-propyl alcohol and ethyl alcohol) as reaction media. The degrees of substitution (D.S.is) of etherification products after 1, 3, 5 and 7 days were determined. The D.S.'s of the first day were used as reference for considering the extent of the reactivity of sodium ions whereas those of third, fifth and seventh days as indicators of the inducing tendency or promotion for further etherification of cellulose. From this experiment, the extent of the reactivity of sodium ions was found to be affected by temperature, reaction time and by the nature of reaction media and of cellulose. By comparison, the most satisfactory result was obtained by using methyl ethyl ketone as a reaction medium. Methyl ethyl ketone is, thus, considered as an excellent reaction medium with high reactivity of sodium ions and with the preferred promotion for further etherification under the reaction conditions of this investigation.