| 摘要 |
Cellulose ethers which are in the form of water-swollen flakes are converted into a filamentary or fibrous form by extruding them while in a water-swollen state through holes whose diameter does not exceed 2 mm. into air and the filaments or fibres thereby formed are then dried. The dried filaments or fibres thus formed may be cut into short lengths to form pellets. The cellulose ethers to be extruded may contain 20 to 70% of water. The invention is applicable to any cellulose ether which is soluble in an organic solvent such as methanol or acetone, or in water or aqueous solutions of sodium hydroxide. The ether may be methyl, ethyl, hydroxyethyl carboxymethyl or cyanoethyl cellulose. The cellulose ethers are made in a conventional manner and may be neutralized, washed and otherwise purified before extrusion. The extrusion may be effected at room temperature or at temperatures up to 80 DEG C. Cellulose ethers which have been converted into filamentary or pellet form according to the invention dissolve more rapidly in their appropriate aqueous or organic solvents than do cellulose ethers in the form of powder produced by pulverizing flakes of the cellulose ether.
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