Abstract: Paper size mixtures which are prepared by mixing an aqueous suspension of a digested cationic starch with a finely divided, aqueous polymer dispersion which is the paper size and emulsifying the C.sub.14 -C.sub.22 -alkyldiketene in this mixture at not less than 70.degree. C. are used for engine and surface sizing of the paper.

Abstract: The printability of paper is improved by applying an aqueous coating agent consisting of(a) 100 parts by weight of a finely divided pigment,(b) from 5 to 70 parts by weight, based on solids, of a cationic aqueous polymer dispersion of a paper size and(c) from 0.01 to 10 parts by weight of a surfactant which interferes with the formation of the surface size and/or of a polymeric dispersantin an amount of from 0.5 to 4 g/m.sup.2 to one or both surfaces of the paper and drying the coated paper.

Abstract: Sizes for paper are based on finely divided aqueous dispersions of copolymers which are obtainable by copolymerization of from 10 to 56 parts by weight of a monomer mixture of(a) from 20 to 65% by weight of (meth)acrylonitrile,(b) from 35 to 80% by weight of one or more acrylates of monohydric, saturated C.sub.3 -C.sub.8 -alcohols and(c) from 0 to 10% by weight of other ethylenically unsaturated copolymerizable monomers by an emulsion polymerization method in 100 parts by weight of an aqueous solution of from 1.7 to 25% by weight of a degraded starch having a viscosity .eta..sub.i of from 0.12 to 0.50 dl/g, at from 40.degree. to 100.degree. C. in the presence of a peroxide-containing initiator.

Abstract: Sizing agents for paper are based on finely divided aqueous dispersions of copolymers obtainable by copolymerizing from 40 to 140 parts by weight of a monomer mixture of(a) from 20 to 65% by weight of (meth)acrylonitrile,(b) from 35 to 80% by weight of one or more acrylates of monohydric saturated C.sub.3 -C.sub.8 -alcohols and(c) from 0 to 10% by weight of other ethylenically unsaturated copolymerizable monomers,the weight percentages (a), (b) and (c) always adding up to 100, in the manner of an emulsion polymerization in 100 parts by weight of an aqueous solution containing in solution from 2.7 to 15% by weight of a degraded starch having a viscosity n.sub.i from 0.04 to less than 0.12 dl/g at from 40.degree. to 100.degree. C. in the presence of a peroxide initiator.

Abstract: Process for the manufacture of shaped articles of a mixture of polystyrene and a copolymer of ethylene with vinyl ester, acrylate or methacrylate. To this end, the said copolymers having a content of from 3 to 40% by weight of unsaturated ester are reacted with monomeric styrene in aqueous suspension in the presence of free-radical polymerization initiators. Whereas a portion of the styrene used is directly grafted onto the ethylene copolymer, the remainder of the polymerized styrene is present in a finely divided state as a homopolymer beside or within the grafted ethylene copolymer. There are obtained homogeneous shaped articles having a styrene content of more than 50% by weight.