A METHOD OF PRODUCING OXIDIZED OR MICROFIBRILLATED CELLULOSE

摘要

The invention relates to a method of producing oxidized or microfibrillated cellulose (MFC). According to the invention there is provided an aqueous pulp suspension with a consistency of at least 15 %, and at least one oxidant is added to the suspension to oxidize cellulosic hydroxyl groups in the suspension under mechanical mixing or shearing. The oxidized suspension, washed and diluted to a lower consistency, is subjected to homogenization to yield gel-like MFC. Alkali hypochlorite may be used as oxidant, and preferred mediating oxidation catalysts are AZADO and TEMPO. Alkali bromide may be used as a cocatalyst. The MFC product, which as a suspension has an increased viscosity, is suitable as a means of regulating viscosity or for production of films and composites.