Cationic polymer dispersions, method for producing said dispersions and use thereof

摘要

The invention relates to water-in-water polymer dispersions containing a polymer A with a cationic monomer fraction of up to 60 wt. % and at least one polymer dispersant B, based on cationised dialkylaminoalkyl (meth)acrylamides with an average molecular weight of between 75,000 and 350,000 g/mol. The invention also relates to a method for producing said dispersions and to the use of the latter.

主权项

1. A method of producing a cationic water-in-water polymer dispersion comprising the step of free-radically polymerizing one or more monomers in an aqueous dispersion of a polymeric cationic dispersant B to form a cationic polymer A wherein the monomers comprise
(a) from 1 to 60 wt. % based on the weight of the cationic polymer A of cationized N-alkyl- or N,N-dialkylaminoalkyl (meth)acrylates and/or cationized N-alkyl- or N,N-dialkylaminoalkyl(meth)acrylamides, and (b) from 40 to 99 wt. % by based on the weight of the cationic polymer A of nonionic monomers, and the cationic polymeric dispersant B has an average molecular weight Mw of from 75,000 to 350,000 g/mol and is prepared from (c) from 30 to 100 wt. % based on the weight of the cationic polymeric dispersant B of cationized N-alkyl- or N,N-dialkylaminoalkyl(meth)acrylamides and/or cationized N-alkyl- or N,N-dialkyl(meth)acrylamides, and (d) from 0 to 70 wt. % by based on the weight of the cationic polymeric dispersant B of nonionic monomers, and wherein the free radical polymerization occurs in the presence of redox free radical initiators consisting of sodium peroxydisulfate, sodium disulfite and tert.-butylhydroperoxide.