Process for the derivatization of cellulose

A process for derivatization of cellulose comprising:

• a) mixing cellulose with a viscosity below 900 ml/g with an aqueous solution to obtain a liquid, wherein said liquid is selected from the group consisting of a solution of cellulose, and a combination of a solution of cellulose and a colloid system comprising cellulose comprising cellulose particles having a diameter of 200 nm or less, wherein cellulose which has not been dissolved and/or suspended to a particle size with an average diameter of between 5-200 nm is removed, wherein particles of cellulose in the liquid have an average diameter of between 5-200 nm and wherein the aqueous solution has a temperature below 20° C., and a pH above 12;
• b) subjecting the liquid to at least one step selected from the group consisting of
• i) decreasing the pH of the liquid by at least 1 pH unit, and
• ii) increasing the temperature of the liquid by at least 20° C.;
• and
• c) derivatization of the cellulose in the liquid.