Abstract: The invention relates to a process for production of expanded pellets from a polymer melt comprising a blowing agent, said process comprising the steps of: a) pressing the polymer melt comprising a blowing agent through a perforated disk controlled to a temperature between 150° C. and 280° C. and into a pelletizing chamber, b) using a cutting device to comminute the polymer melt pressed through the temperature-controlled perforated disk into individual expanding pellets, c) discharging the pellets from the pelletizing chamber using a liquid stream, wherein the blowing agent comprises CO2 or N2 or a combination of CO2 and N2 and the pelletizing chamber is traversed by a stream of liquid which is controlled to a temperature between 10° C. and 60° C. and the pressure of which is from 0.

Abstract: The invention relates to a process for production of expanded pellets from a polymer melt comprising a blowing agent, said process comprising the steps of: a) pressing the polymer melt comprising a blowing agent through a perforated disk controlled to a temperature between 150° C. and 280° C. and into a pelletizing chamber, b) using a cutting device to comminute the polymer melt pressed through the temperature-controlled perforated disk into individual expanding pellets, c) discharging the pellets from the pelletizing chamber using a liquid stream, wherein the blowing agent comprises CO2 or N2 or a combination of CO2 and N2 and the pelletizing chamber is traversed by a stream of liquid which is controlled to a temperature between 10° C. and 60° C. and the pressure of which is from 0.

Abstract: An apparatus suitable for producing shaped bodies comprising thermoplastic polymers from monomers which form such polymers in a batch process comprises a) at least one reactor suitable for the batchwise preparation of a melt of a thermoplastic polymer from monomers which form such a polymer, b) a piping system suitable as circulation line for the melt of the thermoplastic polymer and c) at least one apparatus suitable for the production of shaped bodies from the melt of a thermoplastic polymer, wherein the reactor or reactors a) is/are connected to the piping system b) and the apparatus or apparatuses c) is/are connected to the piping system b), and an apparatus for producing shaped bodies comprising thermoplastic polymers in such an apparatus.

Abstract: Polymeric material (I) comprising

Abstract: In the process and a correspondingly appropriate device for preparing homo- or copolymers of at least one of the, polymerizable monomers of the group consisting of styrene, butadiene, vinyl chloride, vinyl acetate, vinylidene chloride, alkyl (meth)acrylatc (meth)acrylic acid, (meth)acrylonitrile and (meth)acrylamide reaction is carried out at at least 40° C. in the presence of a dispersing auxiliary and of a free-radical polymerization initiator such that at least 85% by weight of the polymer is formed from these monomers.

Abstract: The invention relates to a process for the drying of coagulated water-containing rubber particles. These are treated with an aqueous solution of any desired substances in monodisperse solution in water in such a way that, at least for some period, the surface of the rubber particles is completely covered by the aqueous solution. It is preferable to use an aqueous solution of substances selected from the group consisting of salts, alcohols, acids and sugars. This method can reduce the internal water content between the particles resulting from coagulation, without major usage of energy or time.

Abstract: A method of on-line monitoring and control of monomer conversion in emulsion polymerization includes continuously balancing, as from an initialization time, the heat QIN, introduced into the reactor, the reaction enthalpy QRE introduced via the monomer feed, and the heat which has been removed from the reactor QOUT, and calculating an amount of heat which has not been removed QAD which would lead to an increase in the internal temperature and the internal pressure of the reactor in the event of a spontaneous adiabatic reaction. A check is carried out as to whether the potential adiabatic temperatures and pressures always lie below prescribed upper limits. If the upper limits are exceeded, the monomer feed to the reactor is throttled back or interrupted.

Abstract: In a process for the homopolymerization of vinylaromatic monomers or the copolymerization of vinylaromatic monomers and dienes, the monomers are polymerized in the presence of at least one alkali metal organyl, at least one magnesium organyl and at least one aluminum organyl. The invention also provides an initiator composition for carrying out the process.