Cellulose suspension, method for the production and use thereof
AssigneeLenzing Aktiengesellschaft
InventorsJohann Männer, Martina Opietnik, Josef Innerlohinger, Gerhard Reiter, Markus Hager
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Abstract
The present invention relates to a phase-stable suspension of cellulose II in water, having a high water retention capacity and a cellulose concentration between 0.1 and 5.0% by weight, a method of its preparation, and its use.
Claims13
A phase-stable suspension of cellulose II in water, having a high water retention capacity, wherein said suspension has a cellulose concentration between 0.1 and 5.0% by weight and wherein the viscosity (in [Pa*s] at a shear rate of 50 s−1) and the water retention capacity (in %) as a function of the cellulose concentration x (in % by weight, related to the total quantity of the suspension) of said suspension have the following relationship:
- (viscosity at 50 s−1/WRC)*10000<0.4038*x2.8132
A method for preparing a phase-stable suspension of cellulose II in water, having a high water retention capacity, comprising the following steps:
- a. preparing a spinning dope with 10 to 15% by weight of cellulose according to the lyocell process,
- b. precipitating the cellulose, whereby a material containing NMMO and cellulose is obtained,
- c. washing the material until it is substantially NMMO-free,
- d. enzymatic treatment of the moist material which has been washed substantially free of NMMO,
- e. comminution in a comminution unit, whereby a coarse cellulose suspension is obtained, and
- f. microcomminution in a high pressure homogenizer into a stable microsuspension.
Dependencies are inferred from the claim text.