| 摘要 |
PROBLEM TO BE SOLVED: To provide methods for producing vinyllactam copolymers, which comprise causing radical polymerization of water-soluble N-vinyllactam and hydrophobic comonomers in an organic solvent in the presence of an initiator. SOLUTION: The following process measures are combined appropriately and comprise (i) performing polymerization under reflux, (ii) adding at least 5 mol% of N-vinyllactam to the polymerization mixture if at least 70 mol% of the total amount of hydrophobic monomer used have completely reacted, (iii) returning the condensate formed in the reflux from below to the polymerization mixture, (iv) introducing the initiator in the form of a solution in an organic solvent from below into the polymerization mixture, (v) adding N-vinyllactam to the reflux, (vi) distilling off a portion of the solvent and continuing polymerization following conversion of 70 to 99% by weight of the N-vinyllactam used, (vii) introducing at least one monomer from below into the polymerization mixture, and (viii) performing polymerization under pressure so as to avoid vaporization of the component. COPYRIGHT: (C)2008,JPO&INPIT
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