Abstract: Hairsetting compositions comprise as film-formers copolymers based on tert-butyl acrylate or tert-butyl methacrylate having a K value of from 10 to 50 which are obtainable by free-radical polymerization of A) from 30 to 72% by weight of tert-butyl acrylate or tert-butyl methacrylate or a mixture thereof as monomer A, B) from 10 to 28% by weight of acrylic acid or methacrylic acid or a mixture thereof as monomer B, and C) from 0 to 60% by weight of a free-radically copolymerizable monomer or of a free-radically copolymerizable monomer mixture as monomers C, where at least one of the monomers C produces a homopolymer having a glass transition temperature of less than 30° C., the carboxyl groups of the copolymers being partially or completely neutralized.

Abstract: Process for preparing polymers which are water-soluble or water-dispersible or which, if consisting of monomers with neutralizable radicals, are soluble in water or dispersible in water in neutralized form, by subjecting (a) ethylenically unsaturated monomers to free-radical polymerization in the presence of (b) polyalkylene oxide-containing silicone derivatives.

Abstract: A process for preparing highly concentrated aqueous solutions of low molecular mass homopolymers of N-vinylpyrrolidone by free-radical solution polymerization in an aqueous medium with H2O2 as initiator comprises carrying out the polymerization in the presence of from 0.1 to 30% by weight, based on N-vinylpyrrolidone, of a polymerization regulator which is selected from the group consisting of C1-C6-alkanols, hydroxylamine salts and water-soluble compounds containing sulfur in bonded form.

Abstract: Hair setting lotion which are not subject to hydrolysis and which are made up ofA) 0.5-20% by weight of a nonionic or anionic homo- or copolymer of at least 70% by weight of N-vinylcaprolactam (polymer A), andB) 0.5-20% by weight of a further film-forming polymer (polymer B), selected from the group consisting of polyamides, polyurethanes, and homo- and copolymers of monoolefinically unsaturated monomers.

Abstract: An aqueous copolymer dispersion is prepared by free-radical emulsion co-polymerization of a monomer mixture ofi) from 10 to 70% by weight of at least one nonionic monomer A having a water-solubility of more than 60 g/l at 25.degree. C., and being selected from the group consisting of N-vinyllactams having from 6 to 8 carbon atoms, N-vinylformamide and N-methyl-N-vinylacetamide,ii) from 30 to 90% by weight of at least one monoethylenically unsaturated hydrophobic monomer B having a water-solubility of less than 60 g/l at 25.degree. C.,and optionally further comprisingiii) up to 5% by weight of at least one monoethylenically unsaturated monomer C which has at least one ionic and/or ionizable functional group,iv) up to 10% by weight of at least one monomer D which has at least 2 ethylenically unsaturated bonds,v) up to 20% by weight of at least one further monoethylenically unsaturated monomer E, which is different from the monomers A and C, and has a water-solubility of >60 g/l at 25.degree. C.

Abstract: The present invention relates to a novel process for preparing water-soluble copolymers of at least one water-soluble N-vinyllactam of the formula I ##STR1## where n=1 or 2, and at least one hydrophobic comonomer having a water-solubility of 1 to 85 g/l, by free-radical polymerization in aqueous solution.

Abstract: A process for the preparation of low-hydrazine polymers based on basic vinyl monomers by free-radical solution polymerization in aqueous medium in the presence, as compound which forms free radicals, of an azo compound which has alkoxycarbonyl groups on the carbon atoms adjacent to the azo group.

Abstract: Copolymers which have K values of from 30 to 50 are obtainable by free radical solution polymerization ofA) from 15 to 84.99% by weight of at least one monomer selected from the group consisting of N-vinylpyrrolidone, N-vinylcaprolactam and N-vinylimidazole,B) from 15 to 84.99% by weight of further monoolefinically unsaturated monomers capable of free radical copolymerization andC) from 0.01 to 2% by weight of at least one monomer capable of free radical copolymerization and having at least two non-conjugated olefinic double bondsin alcoholic solution.

Abstract: Chemical impurities contained in N-vinylpyrrolid-2-one are bound by a process in which the anhydride of an organic carboxylic acid is added to the crude N-vinylpyrrolid-2-one.