Aqueous dispersions of water-soluble polymers of N-vinylcarboxamides contain,
based on 100 parts of water,
(A) from 5 to 80 parts by weight of water-soluble polymer containing N-vinylformamide
units and/or N-vinylacetamide units and having particle sizes of from 50 nm to
2 m and
(B) from 1 to 50 parts by weight of at least one polymeric dispersant which
is incompatible with the water-soluble polymers (A) in aqueous solution, which
dispersions are prepared by polymerizing
(A) from 5 to 80 parts by weight of N-vinylformamide and/or N-vinylacetamide,
if desired together with other monoethylenically unsaturated monomers which form
water-soluble polymers therewith, and
(B) from 1 to 50 parts by weight of at least one polymeric dispersant which
is incompatible with the polymers, formed from the monomers (A), in aqueous solution,
in 100 parts by weight of water, at from 30 to 95 C. in the presence of
from 0.001 to 5.0% by weight, based on the monomers used, and the aqueous dispersions
of water-soluble polymers are used as drainage aids, flocculants and retention
aids and as wet and dry strength agents and as fixing compositions in papermaking.
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