A facile method to prepare methylcellulose from annual plants and wood using iodomethane

Abstract

A novel facile method was developed to prepare methylcellulose from miscanthus, cardoon and eucalyptus. Pulps were obtained by the impregnation rapid steam pulping process (IRSP). A total-chlorine-free (TCF) method was used to bleach the pulps with hydrogen peroxide. Bleached pulps were mercerized in 40% NaOH solution for one hour at ambient temperature. Mercerized cellulose reacted with iodomethane in 2-propanol slurry at 60°C for 22 h. Mercerization and methylation were repeated. Intrinsic viscosities of methylcellulose were measured in 4% NaOH solution. Super-molecular substitution patterns of methylcellulose were determined by 13C NMR. Molecular weights of methylcellulose were measured in dimethyl sulfoxide by gel permeation chromatography. Pulping severity is a key factor influencing the properties of the methylcellulose prepared.