Abstract: The invention relates to a process for the production of thermoplastic moulding compounds, in particular for the production of acrylonitrile-butadiene-styrene (ABS), wherein at least a first reagent (11) and a second reagent (12) of the thermoplastic moulding compounds are fed to a loop conduit (29) which comprises a static mixer (36), wherein the reagents (11, 12) are pressed in loops through the loop conduit (29) and passing the static mixer (36), whereby the reagents (11, 12) are dispersed to form a dispersion (15) in the static mixer (36). The invention also relates to a thermoplastic moulding compound that is produced by the inventive process.

Abstract: The invention relates to a process for the production of thermoplastic moulding compounds, in particular ABS, wherein at least a first reagent (11) and a second reagent (12) of the thermoplastic moulding compounds are fed to a gear pump (10) which comprises a housing and at least a first gear wheel that is rotatable relative to the housing about a first axis, and a second gear wheel that is rotatable relative to the housing about a second axis, wherein a loop conduit (29) is provided, and wherein the reagents (11, 12) are pressed in a loop through the loop conduit (29) and passing the gear wheels, whereby the reagents (11, 12) are dispersed to form a dispersion (15) in the gear pump (10). The invention also relates to a thermoplastic moulding compound that is produced by the inventive process.

Abstract: The invention relates to a process for the production of thermoplastic moulding compounds, in particular for the production of acrylonitrile-butadiene-styrene (ABS), wherein at least a first reagent (11) and a second reagent (12) of the thermoplastic moulding compounds are fed to a loop conduit (29) which comprises a static mixer (36), wherein the reagents (11, 12) are pressed in loops through the loop conduit (29) and passing the static mixer (36), whereby the reagents (11, 12) are dispersed to form a dispersion (15) in the static mixer (36). The invention also relates to a thermoplastic moulding compound that is produced by the inventive process.

Abstract: The invention relates to a process for the production of thermoplastic moulding compounds, in particular ABS, wherein at least a first reagent (11) and a second reagent (12) of the thermoplastic moulding compounds are fed to a gear pump (10) which comprises a housing and at least a first gear wheel that is rotatable relative to the housing about a first axis, and a second gear wheel that is rotatable relative to the housing about a second axis, wherein a loop conduit (29) is provided, and wherein the reagents (11, 12) are pressed in a loop through the loop conduit (29) and passing the gear wheels, whereby the reagents (11, 12) are dispersed to form a dispersion (15) in the gear pump (10). The invention also relates to a thermoplastic moulding compound that is produced by the inventive process.

Abstract: A process of polymerization of a vinylic monomer uses a polymerization regulator/initiator that is a compound represented by Formula I.

Abstract: The invention provides a process for preparing expandable styrene polymers which comprises the steps of: (a) adding an aqueous phase comprising a suspension stabilizer and an organic phase comprising styrene and an initiator to a reactor, (b) commencing the addition of a blowing agent at a styrene conversion in the range from 40 to 70% and adding the blowing agent over a period ranging from 30 to 60 minutes, (c) adding a stabilizer to stabilize the bead size distribution of the expandable styrene polymer at a styrene conversion in the range from 65 to 99%.

Abstract: Process for preparing polymers by controlled free-radical polymerization, wherein the polymerization of one or more free-radically polymerizable monomers of the general formula (I) where R1, R2, R3 are each H, C1-C4-alkyl, R4 is C(?O)0R5, C(?O)NHR15, C(?O)NR5R6, OC(?O)CH3, C(?O)OH, CN, aryl, hetaryl, C(?O)OR5OH, C(?O)OR5Si(OR5)3, halogen, NHC(O)H, P(?O)(OR7)2, R5 is C1-C20-alkyl, R15 is C1-C20-alkyl, R6 is C1-C20-alkyl, R7 is H, C1-C20-alkyl, in the presence of a. one or more catalysts comprising Cu in the form of Cu(0), Cu(I), Cu(II) or mixtures thereof, b. one or more initiators selected from the group consisting of organic halides or pseudohalides, c. one or more ligands, d. optionally one or more solvents, e. optionally one or more inorganic halide salts, and comprises the steps i) addition of the catalyst a., ii) optionally addition of monomers of the general formula (I), iii) optionally addition of solvent d., iv) addition of ligand c., v) addition of initiator b.

Abstract: The present invention provides a novel one-step process for preparing an aqueous polymer dispersion by the free radical aqueous emulsion polymerization comprising mixing at least water, a dispersant, and an oil-soluble initiator; raising a temperature from the starting to the end reaction temperature while metering at least ethylenically unsaturated monomers and a water-soluble initiator into a reaction vessel, conducting polymerization of the monomers in the presence of the water-soluble initiator at a temperature up to the end reaction temperature, and when the temperature has reached the end reaction temperature, conducting polymerization by the oil-soluble initiator. The oil-soluble initiator is inactive at the starting reaction temperature and becomes more active as a temperature approaches the end reaction temperature at which the oil-soluble initiator is fully active.

Abstract: The invention provides a process for preparing expandable styrene polymers which comprises the steps of: (a) adding an aqueous phase comprising a suspension stabilizer and an organic phase comprising styrene and an initiator to a reactor, (b) commencing the addition of a blowing agent at a styrene conversion in the range from 40 to 70% and adding the blowing agent over a period ranging from 30 to 60 minutes, (c) adding a stabilizer to stabilize the bead size distribution of the expandable styrene polymer at a styrene conversion in the range from 65 to 99%.

Abstract: The invention relates to a process for continuously preparing styrene polymers by anionic spray polymerization, which comprises i) styrene and the initiator solution being mixed in a dynamic or static mixer and then the mixture being sprayed, ii) the resultant droplets passing from the liquid monomer state to the melted polymer state during their free fall in the spraying tower, iii) the melt droplets being collected as a melt at the foot of the tower, the melt having a monomer content of below 1%, preferably below 0.1% (<1000 ppm), and being discharged by suitable means.

Abstract: An aqueous polymer dispersion is prepared by free radical aqueous emulsion polymerization of at least one ethylenically unsaturated compound (monomer) in the presence of at least one dispersant and at least one water-soluble and one oil-soluble free radical initiator by a process in which the polymerization temperature increases from the starting reaction temperature TS to the end reaction temperature TE in the course of the polymerization reaction.

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: The surfaces of apparatuses and apparatus parts for chemical plant construction, including, for example, apparatus, container and reactor walls, discharge apparatuses, fittings, pumps, filters, compressors, centrifuges, columns, heat exchangers, dryers, comminuting machines, internals, packings and mixing elements, are coated by a process wherein protuberances having a mean height of from 100 nm to 50 &mgr;m with a mean spacing of from 100 nm to 100 &mgr;m are produced on the surface to be coated and the coating is applied thereon by currentless deposition of a metal layer or of a metal-polymer dispersion layer with the aid of a plating bath which contains a metal electrolyte, a reducing agent and optionally a polymer or polymer blend to be deposited, in dispersed form.

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: The surfaces of apparatuses and apparatus parts for chemical plant construction, including, for example, apparatus, container and reactor walls, discharge apparatuses, fittings, pumps, filters, compressors, centrifuges, columns, heat exchangers, dryers, comminuting machines, internals, packings and mixing elements, are coated by a process wherein protuberances having a mean height of from 100 nm to 50 &mgr;m with a mean spacing of from 100 nm to 100 &mgr;m are produced on the surface to be coated and the coating is applied thereon by currentless deposition of a metal layer or of a metal-polymer dispersion layer with the aid of a plating bath which contains a metal electrolyte, a reducing agent and optionally a polymer or polymer blend to be deposited, in dispersed form.

Abstract: Catalyst systems of the type comprising the Ziegler-Natta catalysts contain, as active components,a) a titanium-containing solid component which contains titanium, magnesium, halogen and a carboxylic ester as an electron donor, and, as a cocatalyst,b) an aluminum compound andc) if required, a further electron donor, a compound of the following formula IR.sub.m.sbsb.1 Al--(OCOR.sup.1).sub.m.sbsb.2 (I)whereR and R.sup.1 are identical or different and are each hydrogen or C.sub.1 -C.sub.8 -alkyl andm.sub.1 and m.sub.2 are each 1 or 2 and sum to give 3, being used as aluminum compound b) in the preactivation of the titanium-containing soild compound a) with the cocatalyst.

Abstract: A novel process for the preparation of Ziegler-Natta catalyst systems containing, as active components,a) a titanium-containing solid component which contains titanium, magnesium, halogen and a carboxylic ester and, as a cocatalyst,b) an aluminum compound andc) if required, a further electron donor is described. Ziegler-Natta catalyst systems which are obtainable by this process, the preparation of polymers of propylene with the aid of these catalyst systems, the polymers obtainable thereby and films and moldings of these polymers are also described.

Abstract: Two absorbent layer materials for a sample liquid are connected with one another in such a way that the sample liquid can pass through from one layer into the other layer through the connecting surface between the layers a hot melt adhesive is applied to the first layer material in the form of a discontinuous coating and the second layer material is pressed on while the melt adhesive is still sufficiently hot. The amount of the melt adhesive and the pressing-on force are adjusted to one another with regard to the surface properties in such a manner that, even after the application and pressing on of the second layer material, a continuous liquid-permeable melt adhesive layer does not result.

Abstract: Catalyst systems of the Ziegler-Natta type contain, as active componentsa) a titanium-containing solid component in whose preparation a titanium compound, a compound of magnesium, a halogenating agent and an electron donor component are used,b) an aluminum compound andc) as a further electron donor component, an organosilicon compound of the formula (I)R.sup.1 R.sup.2 Si(OR.sup.3).sub.2 (I)where R.sup.1 is C.sup.1 -C.sub.10 -alkyl or C.sub.3 -C.sub.8 -cycloalkyl, excluding sec-butyl, R.sup.2 is sec-butyl and R.sup.3 is C.sub.1 -C.sub.8 -alkyl. The catalyst systems are particularly suitable for the preparation of polymers of C.sub.2 -C.sub.10 -alk-1-enes.

Abstract: High-flow propylene/ethylene copolymers which have a melt flow index of from 2 to 200 g/min under a load of 2.16 kg at 230.degree. C. and which may be produced from the gas phase by polymerization in two stages in an agitated fixed bed in the presence of hydrogen acting as chain stoppage regulator and using a Ziegler-Natta catalyst system comprising a titaniferous solid component which contains a magnesium compound on finely divided silicon oxide or on finely divided aluminum oxide or on a finely divided aluminum silicate having the empirical formula SiO.sub.2.aAl.sub.2 O.sub.3, where a stands for a value between 0.001 and 2, and an aluminum component, by means of a procedure comprisinga) a first polymerization stage in which propylene is polymerized under a pressure of from 20 to 40 bar and at a temperature of from 60.degree. to 90.degree. C.