Abstract: A thermoplastic molding composition having reduced gloss sensitivity and no unpleasant odor is produced from a graft copolymer and a thermoplastic polymer. The graft copolymer is produced from a soft elastomeric particulate graft base obtained by emulsion polymerization of a conjugated diene alone or with a small amount of a monoethylenically unsaturated monomer, using an inorganic radical generating substance and a limited amount of chain transfer agent, upon which is grafted a vinyl aromatic monomer and acrylonitrile and optionally another monoethylenically unsaturated monomer using an inorganic radical generating substance while the use of a chain transfer agent is excluded. The thermoplastic polymer is a copolymer of a vinyl aromatic monomer and acrylonitrile and optionally an additional monoethylenically unsaturated monomer. The thermoplastic molding composition has a low level of unpleasant odor coupled with reduced gloss sensitivity and good mechanical properties.

Abstract: Pelletized materials based on at least one thermoplastically processable polymer, where the pellets have less than 10% of concave regions and otherwise are convex in every other region, this being determined by means of incident-light interference-contrast spectroscopy, by taking the average value for the ratios of the outline area to the entire outline area for an assembly of pellets.

Abstract: An apparatus intended for extruding thermoplastics and having at least one devolatilization orifice and, if desired, also at least one dewatering orifice, which has been equipped with a metal-wire-mesh composite sheet, with a finely perforated metal sheet, or with a slit diaphragm.

Abstract: A polybutadiene latex is prepared by a process in which butadiene is polymerized by free radical emulsion polymerization in the presence of initiator and, if required, dispersants and further conventional assistants, the polymerization being carried out in the presence of reactive comonomers in such a way that the heat flow of 43 watt/kg solids content of the polymerization mixture is not exceeded. Owing to the presence of reactive comonomers, the reaction rate at the beginning of the reaction is increased, with the result that an overall flatter heat flow profile is obtained. A preferred reactive comonomer is styrene.

Abstract: Thermoplastic molding materials containing the following ingredients with regard to components A-F: A) 5-70 wt. % of at least one graft copolymer A) consisting of a rubber elastic base with a glass transition temperature below 0° and a grafted overlay made of a styrene compound and acrylonitrile or methacrylonitrile or mixture thereof in addition to, optionally, other monoethylenically unsaturated monomers, B) 29-90 wt. % of a hard copolymer made of at least one styrene compound, acrylonitrile or methacrylonitrile or mixtures thereof and, optionally, other monoethylenically unsaturated monomers, C) 0-5 wt. % of at least one three-block copolymer X-Y-X with a middle block Y propylenoxide units and terminal block X made of ethyleneoxide units, D) 0.01-5 wt. % of at least one butylated reaction product of cresol with dicyclopentadiene, E) 0.01-5 wt. % of at least one thiocarboxylic acid ester, F) 0.01-5 wt.

Abstract: Process for preparing rubber-containing thermoplastic molding compositions, by using polymerization to prepare at least one elastomeric polymer A and at least one thermoplastic polymer B, and mixing these with one another, the elastomeric polymer A being present in dispersed form in an aqueous phase after the polymerization, which comprises adding at least one pH-buffer system to the aqueous phase after the polymerization of component A has ended.

Abstract: The invention relates to a method for producing caoutchouc particles (K) by means of emulsion polymerisation in the presence of an emulsifier and a polymerisation initiator. Said particles contain A) 80 to 100 wt. % of one or more conjugated diene monomers (A) in relation to (K) and B) 0 to 20 wt. % of one or more monoethylenically unsaturated comonomers (B) in relation to (K) in the polymerised form. The inventive method is characterised in that 1) a mixture (M1) containing water and an emulsifier is provided, 2) a mixture (M2) containing one or more monomers in the monomer or polymerised form selected from styrole, &agr;-methylstyrole, butadiene, n-butylacrylate, MMA and acrylnitrile and optionally comonomers is added, 3) polymerisation of the obtained mixture starts in the presence of a polymerisation initiator at temperature of 5 to 95° C., 4) a mixture (M3) containing 0 to 100 wt. % of the comonomers (B) in relation to (B) and 0 to 25 wt.

Abstract: A polybutadiene latex is prepared by a process in which butadiene is polymerized by free radical emulsion polymerization in the presence of initiator and, if required, dispersants and further conventional assistants, the polymerization being carried out in the presence of reactive comonomers in such a way that the heat flow of 43 watt/kg solids content of the polymerization mixture is not exceeded.

Abstract: Thermoplastic molding compositions comprising, based on the components A) to F),

Abstract: The invention relates to a method for producing caoutchouc particles (K) by means of emulsion polymerisation in the presence of an emulsifier and a polymerisation initiator. Said particles contain A) 80 to 100 wt. % of one or more conjugated diene monomers (A) in relation to (K) and B) 0 to 20 wt. % of one or more monoethylenically saturated comonomers (B) in relation to (K) in the polymerised form The inventive method is characterised in that 1) a mixture (M1) containing water and an emulsifier is provided, 2) a mixture (M2) containing one or more monomers in the monomer or polymerised form selected from styrole, &agr;-methylstyrole, butadiene, n-butylacrylate, MMA and acrylnitrile and optionally comonomers is added, 3) polymerisation of the obtained mixture starts in the presence of a polymerisation initiator at temperature of 5 to 95° C., 4) a mixture (M3) containing 0 to 100 wt. % of the comonomers (B) in relation to (B) and 0 to 25 wt.

Abstract: Shear forces are used for essentially salt-free coagulation of plastics dispersions or rubber dispersions. For this, method of use is made of an apparatus with at least one shearing module which has a stator and a rotor arranged within the stator, where the surfaces facing toward one another in the stator and in the rotor are in each case smooth, or at least the rotor exhibits a structure formed on its surface and facing from this in the direction of the stator, and between the stator and the rotor there is a gap of predetermined gap width. The process is carried out by passing the dispersion to be coagulated through the gap between stator and rotor and precipitating the dispersion by rotation of the rotor with predetermined shear rate and shear deformation.

Abstract: In a process for precipitating microsuspension polymers from a suspension comprising them, a polymer dispersion prepared by emulsion polymerization is added to the suspension.

Abstract: A thermoplastic molding composition having little intrinsic color is produced from a graft copolymer and a thermoplastic polymer. The graft copolymer is produced from a soft elastomeric particulate graft base obtained by polymerization of a conjugated diene alone or with a small amount of a monoethylenically unsaturated monomer, upon which is grafted a vinylaromatic monomer and acrylonitrile and optionally another monoethylenically unsaturated monomer. The thermoplastic polymer is a copolymer of a vinylaromatic monomer and acrylonitrile and optionally an additional monoethylenically unsaturated monomer. The thermoplastic molding composition has a low level of intrinsic color coupled with good mechanical properties and can be processed by, for example, extrusion, injection molding, calendaring, blow molding, compression molding, or sintering.

Abstract: A process for preparing thermoplastics or polymer blends comprising (A) from 5 to 95% of a water-moist elastomer component containing up to 60% of residual water, (B) from 5 to 95% of a thermoplastic polymer, (C) from 0 to 95% of a further polymer, and (D) from 0 to 70% of additives, said process comprising mixing the components A to D in an extruder with mechanical dewatering of component A, wherein the extruder has at least two rotating screws and, in the conveying direction, is essentially composed of a metering section into which component A is fed, a squeeze section which serves for dewatering component A and contains a retarding element and an associated dewatering orifice which is present upstream of the retarding element by a distance corresponding to at least one screw diameter, a feed section in which the thermoplastic polymer B is introduced as a melt into the extruder, a plastication section with mixing or kneading elements, a devolatilization section with an orifice and in which the remaining wat

Abstract: Toughened thermoplastics are prepared by mechanically dewatering a water-moist elastomer component A containing up to 50% by weight of residual water and mixing the resulting dewatered elastomer component A' with a thermoplastic polymer B in a mixing unit, by a process in which the elastomer component A is fed to a twin-screw extruder which has corotating screws and essentially includes, in the transport direction,one unheated metering section in which the elastomer component A is fed to the extruder by a metering means,at least one unheated squeeze section which serves for dewatering and contains at least one retarding element and in each case at least one associated dewatering orifice,at least one section in which the thermoplastic polymer B is introduced as a melt into the extruder,at least one section provided with mixing, kneading or other plasticating elements or combinations of these elements,at least one devolatilization section which is provided with at least one devolatilization orifice and in which

Abstract: Toughened thermoplastics are prepared by mechanically dewatering a water-moist elastomer component A containing up to 60% by weight of residual water and mixing the resulting dewatered elastomer component A' with a thermoplastic polymer B in an extruder, by a process in which the elastomer component A is fed to a twin-screw extruder which has corotating, in each case double-flight, screws and essentially includes, in the transport direction,a metering section in which the elastomer component A is fed to the extruder by a metering means,at least one squeeze section which serves for dewatering and contains at least one retarding element and in each case at least one associated dewatering orifice,at least one section provided with a conveying screw or at least one section provided with mixing, kneading or other plasticating elements or combinations of these elements,at least one section in which the thermoplastic polymer B is introduced as a melt into the extruder,at least one section provided with mixing, knead

Abstract: Toughened thermoplastics are prepared by mixing a water-moist elastomer component A containing up to 60% by weight of residual water with a thermoplastic polymer B and further polymers C and additives D in an extruder with mechanical dewatering of the elastomer component A, by a process in which the components A, B, C and D are fed to a twin-screw extruder which has corotating screws and essentially comprises, in the transport direction,at least one metering section in which the elastomer component A is fed to the extruder by a metering means,at least one squeeze section which serves for dewatering the component A and contains at least one retarding element and in each case at least one associated dewatering orifice,at least one section in which the thermoplastic polymer B is introduced as a melt into the extruder,at least one section provided with mixing, kneading or other plasticating elements or combinations of these elements,at least one devolatilization section which is provided with at least one devolat

Abstract: Polyphenylene ethers are prepared from monohydric phenols by oxidative coupling with oxygen-containing gases in the presence of an oxidation catalyst in an organic solvent by carrying out the polycondensation in the presence of a defoamer.

Abstract: A process for preparing polyphenylene ethers from monohydric phenols which have alkyl substituents in both ortho positions and possibly also in one meta position but not in the para position, by oxidative coupling with oxygen-containing gases in the presence of an oxidation catalyst and of an electrically conducting compound which counteracts the electrostatic charge in the reaction mixture, in organic solution, comprises using as electrically conducting compound a salt of a carboxamide derivative of the formula I ##STR1## or mixtures of such salts, where R.sup.1 is a saturated or singly or multiply unsaturated aliphatic group which can have a terminal phenyl group and which contains a total of 8-30 carbon atoms, it also being possible for these carbon atoms to be interrupted by isolated oxygen atoms,R.sup.2 is hydrogen or C.sub.1 -C.sub.4 -alkyl,A is an aliphatic, araliphatic or cycloaliphatic or aromatic bridge of up to 10 carbon atoms,n and m are each 1 to 3,Q.sup..sym.

Abstract: Vinyl ester resins possess unsaturated terminal groups and are based on polyphenols of the formulaC(ArOH).sub.m (R').sub.p --(CR.sub.2).sub.n --C(ArOH).sub.m (R").sub.p (I)or(ArOH)--CH.sub.2 --Ar--CH.sub.2 --[(ArOH)--CH.sub.2 --Ar--CH.sub.2 ].sub.n --(ArOH) (II)wherein R, R' and R" may be identical or different and are each H or CH.sub.3, Ar is phenylene which is unsubstituted or substituted by methyl or methoxy, n is 0, 1 or 2, m is 1 or 2 and p is 3-m.