| 摘要 |
Disclosed is a method of preparing a modified diallyl-N,N-disubstituted ammonium halide polymer having a cationic charge of about 1 to about 99 mole percent and a RSV of from about 0.2 to about 12 dL/g and a charge density of less than about 7 milliequivalents/g polymer comprising: (a) preparing an aqueous solution comprising one or more diallyl-N,N-disubstituted ammonium halide monomers, about 35 to about 85 percent of the total acrylamide monomer, about 0.1 to about 150,000 ppm based on monomer of one or more chain transfer agents (such as sodium formate or sodium hypophosphite), and optionally about 1 to about 30,000 ppm based on monomer of one or more cross-linking agents (such as N,N-methylenebisacrylamide); (b) initiating polymerization of the monomers; (c) allowing the polymerization to proceed to at least about 5 percent diallyl-N,N-disubstituted ammonium halide monomer conversion and at least about 20 percent acrylamide monomer conversion; and (d) adding the remaining acrylamide monomer and allowing the polymerization to proceed to the desired endpoint. Also disclosed is a method of increasing retention and drainage in a papermaking furnish comprising adding to the furnish an effective amount of a modified diallyl-N,N-disubstituted ammonium halide polymer prepared according to the above method and an effective amount of one or more high molecular weight, water-soluble cationic, anionic, nonionic, zwitterionic or amphoteric polymer flocculants.
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