Abstract: Rubber-modified, impact-resistant molding materials contain, based on the sum of A, B1 and B2,A: from 70 to 98% by weight of a polymer matrix A formed by free radical polymerization of a mixture of from 60 to 90% by weight of styrene and from 10 to 40% by weight of acrylonitrile,B1: from 1 to 29% by weight of a particulate, first graft copolymer B1 which is distributed in the matrix A and consists of a grafting base of polybutadiene and grafts of a copolymer of styrene and acrylonitrile having a mean particle size of about 100-500 nm, andB2: from 1 to 29% by weight of a particulate, second graft copolymer B2 distributed in the matrix A and consisting of a grafting base of polybutadiene and grafts of a copolymer of styrene and acrylonitrile having a mean particle size of from 600 to 10,000 nm, as obtained if both graft copolymers have been prepared by solution and/or mass polymerization and have been incorporated in the polymer matrix in a conventional manner.

Abstract: A process for the continuous preparation of high-impact polystyrene-acrylonitrile (ABS) by free radical-initiated polymerization of a mixture of from 60 to 90% by weight of at least one vinylaromatic monomer and from 10 to 40% by weight of least one further ethylenically unsaturated monomer, in the presence of from 5 to 30% by weight, based on the sum of the monomers, of polybutadiene having a solution viscosity (5% strength by weight in styrene at 25.degree. C.) from 25 to 95 mPa.s and in the presence or absence of a solvent, in at least three consecutive reactors operated essentially without back-mixing, at from 50.degree. to 170.degree. C., phase inversion taking place in one of the reactors, involves carrying out the polymerization as far as phase inversion at 90.degree. C. or below and initiating the polymerization by free radicals from the decomposition of tert-butyl peresters whose half life period at 90.degree. C.

Abstract: Impact-resistant polystyrene acrylonitrile (ABS) is prepared by free radical polymernation of monomeric styrene and acrylonitrile or equivalents thereof in the presence of preformed, dissolved polbutadiene as a grafting base, the solvents used being in particular ethylbenzene and, at least from time to time, the monomers, and phase inversion taking place when the process has progressed to a certain point, in two or more reaction zones, by a continuous process in which the first reaction zone is present at least in duplicate and is in the form of a stirred kettle in each case, so that one stirred kettle is operated batchwise and alternately with the other in such a way that the reaction mixture is polymerized until phase inversion is complete or the initiator has been consumed, and the particular kettle content is then fed continuously to a second reaction zone in the form of a tube reactor.

Abstract: A rubber-modified, impactresistant acrylonitrile-butadiene-styrene (ABS) molding material, as obtained by polymerizing styrene and acrylonitrile in the presence of a preformed rubber, dissolved in monomeric styrene and acrylonitrile and, if necessary, a solvent, wherein the rubber is a styrene-butadiene block copolymer and at least one further polymer which is compatible with the styrene-butadiene block rubber or its polystyrene component and is incompatible with polystyrene-acrylonitrile.

Abstract: (Co)polymers which are composed of one or more monomers from the group comprising(a) the vinyl-aromatic monomers and(b) the ethylenically unsaturated monomersand furthermore contain one or more monomer components (a) or (b), or (a) and (b), as unreacted residual monomers are treated at above the glass temperature of the (co)polymer and in the presence of one or more assistants, which have been added to the (co)polymer. The assistant used is a bicyclic compound of the general formula I ##STR1## where X is a methylene, ethylene, 1,1-ethenyl, 1,2-ethenyl, carbonyl, azo, amino, ether or thioether group which is unsubstituted or substituted by halogen, alkyl, alkenyl, cycloalkyl, aryl, carboxyl, carboxyalkyl, an ether group or a thioether group, R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are each hydrogen, halogen, alkyl, alkenyl, cycloalkyl, aryl, carboxyalkyl or nitrile, R.sup.5 and R.sup.6 are each hydrogen, halogen, alkyl or carboxyalkyl, and R.sup.7 and R.sup.

Abstract: Thermoplastic molding masses comprise a styrene and/or .alpha.-methylstyrene-acrylonitrile copolymer and a polyamide based on piperazine.

Abstract: Thermoplastic molding masses based on the copolymerization of styrene and/or .alpha.-methylstyrene and acrylonitrile, which may be modified to be impact resistant with rubberlike polymers, are made antistatic by adding 0.01 to 1.5 percent by weight of a graft polyol which is a polyhydroxy-polyalkylene polyether modified with styrene-acrylonitrile copolymers.

Abstract: A process for the preparation of branched block copolymers of from 60 to 95% by weight of a monovinyl-aromatic monomer and from 40 to 5% by weight of a conjugated diene by polymerizing the monomers in an inert solvent in the presence of a monolithium-hydrocarbon as the initiator, wherein, in a first process stage (a), from 50 to 80, or where necessary at most 90, % by weight of the total amount of monovinyl-aromatic compound are polymerized to virtually complete conversion in the presence of a relatively small amount of the monolithium-hydrocarbon. This stage is carried out by starting with from 30 to 70% by weight of the vinyl-aromatic monomer and adding from 70 to 30% by weight in the feed, during the polymerization, in such a way that the polymerization temperature, which at the start of the polymerization is from 30.degree. to 40.degree. C., is kept at from 45.degree. to 70.degree. C., with use of reflux cooling. After all the monomer feed has been added, the reaction temperature is lowered to 30.degree.