| 摘要 |
In the papermaking process, a polyampholyte coagulant is used as a retention/drainage/formation aid in a papermaking process; is used to treat coated broke where the white pitch or stickies and pigments are affixed to the long fibers and fiber fines; and is used to clarify the process water where the solids from the white water are either settled out or floated for their removal from the water. As a retention/drainage formation aid, the polyampholyte coagulant polymer is added to the papermaking cellulosic slurry prior to the first or after the last shearing stage, and, optionally, a flocculant may be added either before the addition of the polyampholyte coagulant or before the first or the last shearing stage. The polyampholyte coagulant has a weight average molecular weight from 10 thousand to 20 million, is in emulsion or solution form, and may comprise a copolymer of acrylic acid (anionic) and diallyl dimethyl ammonium chloride (cationic) in a weight percentage ratio range of from about 1:999 to about 99:1 based on the dry weight of the polyampholyte, or may comprise a terpolymer of acrylamide (nonionic), acrylic acid (anionic), and diallyl dimethyl ammonium chloride (cationic).
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