| 摘要 |
<p>#CMT# #/CMT# - Improving transportability of a water-moist cellulose ether composition (I) in a conveying unit, comprises: (a) providing a starting material having a water-moist cellulose ether or a cellulose ether mixture having a moisture content of 25-75 wt.%; (b) optionally adding and mixing in of water and/or optionally adding and mixing in of further additives, (except for water-soluble polymeric additive which contains anionic groups (WSAP)), to the starting material, and (c) adding 0.001-2 wt.% of WSAP or WSAP mixture to the composition obtained in step (a) or in steps (a) and (b), to obtain (I). #CMT# : #/CMT# Improving transportability of a water-moist cellulose ether composition (I) in a conveying unit, comprises: (a) providing a starting material comprising a water-moist cellulose ether or a cellulose ether mixture having a moisture content of 25-75 wt.%, based on the total mass of the starting material; and (b) optionally adding and mixing in of water and/or optionally adding and mixing in of further additives, (except for water-soluble polymeric additive which contains anionic groups (WSAP)), to the starting material, and (c) adding 0.001-2 wt.% of WSAP or WSAP mixture, based on the dry mass of the cellulose ether composition to be prepared, to the composition obtained in step (a) or in steps (a) and (b), to obtain (I) having a moisture content of 45-85 wt.% based on the total mass of the cellulose ether composition. #CMT#USE : #/CMT# The process is useful for: improving transportability of a water-moist cellulose ether composition; and hold-up and distribution of a feedstock. #CMT#ADVANTAGE : #/CMT# The process: avoids comminuting tools, kneaders or extruders; requires low energy and low cost of apparatus; provides high availability; avoids ecologically and toxicologically unsafe substances; uses single conveyor screws or screw cascades of low drive power; and does not require positively conveying units. #CMT#INSTRUMENTATION AND TESTING : #/CMT# Preferred Components: The conveying unit is conveying screw. #CMT#POLYMERS : #/CMT# Preferred Process: The WSAP or the WSAP mixture is added as an aqueous solution or in powder form in step (c), with exclusion of comminuting tools, kneaders or extruders, so that mixing of the WSAP into the granular particles and/or lumps of the cellulose ether composition is avoided. The WSAP or WSAP mixture is distributed in homogeneously in the obtained (I), namely between the granular particles and/or lumps of the water-moist cellulose ether composition or on the respective surface of it, and less than 50% of the WSAP present in the composition is present within the granular particles and/or lumps. In the process: starch, starch ether, guar, guar ether and xanthan are not added in an amount of 0.1-10 wt.%, based on the dry cellulose ether or cellulose ether mixture; and starch, starch ether, guar, guar ether and xanthan is not being present in (I). The process further comprises: (d) drying (I); (e) milling, or combining steps (d) and (e) to take place in one step as combined milling/drying; and (f) optionally further milling steps. (I) is distributed over at least two milling, drying or combined milling/drying plants. Preferred Components: The WSAP or WSAP mixture is water-soluble homo and copolymers based on maleic acid, acrylic acid, methacrylic acid, vinylsulfonic acid, vinylphosphonic acid, styrenesulfonic acid, 2-(meth)acrylamide-2-methylpropanesulfonic acid, 2-(meth)acryloylethanesulfonic acid, 2-(meth)acryloylpropanesulfonic acid and the salts and its esters, including copolymers of the acids with monomers comprising acrylamide, vinyl acetate or vinyl alcohol. The WSAP is an anionic polyacrylamide having an acrylate content of less than 20 wt.% and having a viscosity of less than 1000 mPa.s, measured at a concentration of 1 wt.% in 10% strength by weight of sodium chloride solution at 25[deg] C. The cellulose ether derivative or derivatives is methylcelluloses, hydroxyalkylcelluloses, or carboxymethylcelluloses and its derivatives.</p> |
