FINE-PARTICLED POLYMER DISPERSIONS CONTAINING STARCH

摘要

The invention relates to fine-particled polymer dispersions which contain starch and which are obtained by the radically initiated emulsion copolymerisation of: a) 30 to 60 % by weight of at least one optionally substituted styrene, acrylonitrile and/or methacrylonitrile, b) 5 to 50 % by weight of at least one acrylic acid -C1-C12-alkyl ester and/or a methacrylic acid -C1-C12-alkyl ester, c) 5 to 30 % by weight of at least one olefin, d) 0 to 10 % by weight of at least one other ethylenically unsaturated copolymerisable monomer, and e) 15 to 35 % by weight of a degraded starch. The total (a) + (b) + (c) + (d) + (e) = 100% and refers to the total content of solid material in an aqueous medium in the presence of at least one redox initiator. The invention also relates to a method for producing the aqueous polymer dispersions by the radical emulsion copolymerisation of components (a) to (e) in an aqueous medium in the presence of a redox initiator, to the use of the thus obtained fine-particled polymer dispersions containing starch as resizing agents for paper, paperboard and cardboard.