Process for purification of unreacted vinyl acetate monomers comprising the steps of preliminarily loading an adsorbent agent bed with a mixture comprising an inert gas and fresh vinyl acetate; and feeding said adsorbent agent bed with unreacted vinyl acetate monomers to remove acetic acid.

Process for purification of unreacted vinyl acetate monomers comprising the steps of preliminarily loading an adsorbent agent bed with a mixture comprising an inert gas and fresh vinyl acetate; and feeding said adsorbent agent bed with unreacted vinyl acetate monomers to remove acetic acid.

The invention relates to a process for producing thermoplastic molding materials based on acrylonitrile-styrene-acrylate copolymers (ASA) having improved surface properties, in particular an improved stability of surface quality during storage in a hot and humid environment and a reduced content of residual monomers. The invention further relates to the use of a fluidized bed dryer and/or a flow dryer in the production of thermoplastic ASA molding materials for improving surface quality and the use of a fluidized bed dryer and/or a flow dryer in the production of thermoplastic ASA molding materials for reducing the content of residual monomers. The invention further provides ASA molding materials producible by means of the process according to the invention and also moldings.

A catalyst component for olefin polymerization includes magnesium, titanium, a halogen, an internal electron donor compound, and a precipitation aid. The precipitation aid includes a precipitation aid represented by general formula (I). The precipitation aid represented by general formula (I) includes isomers represented by general formula (I-a) and/or (I-b).

##STR00001##

Disclosed herein is a distributor comprising a first conduit; where the first conduit has an inlet port for charging a heating fluid into the distributor; a second conduit; where the first conduit lies inside the second conduit to define a first annular space therebetween; where the second conduit has an exit port for removing the heating fluid from the distributor; a plurality of plate stacks disposed around the second conduit to define a narrowing second annular space from top to bottom of the distributor; where each successive plate stack has smaller inner diameter than the plate stack located above it; where each plate stack comprises a plurality of plates; where the plurality of plates further define a plurality of conduits, each conduit having a varying width over its length and extending radially outwards from the central passage.

The present invention relates to a process for the production of a polymer using a compound comprising at least 2 unsaturated carbon-carbon bonds, wherein the process comprises a polymerization section and a purification section, wherein the product from the polymerization section is subjected in the purification section to a sequence of purification steps comprising: removal of the vapor phase from the product from the polymerization section by means of flash separation to obtain a first vapor phase and a polymerization product; subjecting the first vapor phase to a compression and condensation treatment to obtain a second vapor phase and a condensed monomer phase; wherein the purification steps are conducted in this order. Such process allows for the optimal utilisation of raw materials in the polymerization process.

The invention relates to an efficient process for the preparation and isolation of rubber particles formed in aqueous media and highly pure rubbers obtained thereby. The invention further relates to copolymer products comprising the same or derived therefrom.

The present invention relates to a process for the production of water and solvent-free hydrogenated nitrile rubber polymers, to the hydrogenated nitrile rubbers and the use thereof.

A process for producing superabsorbent particles, comprising drying of a polymer gel, removal of incompletely dried polymer particles, comminution of the polymer particles removed, recycling of the comminuted polymer particles and storage of the recycled polymer particles.

Provided is method of treating a collection of resin beads (a) comprising the steps of (a) providing the collection of resin beads (a), wherein the resin beads (a) comprise one or more vinyl polymers having quaternary ammonium groups; wherein 90 mole % or more of the quaternary ammonium groups are each associated with a chloride anion; (b) bringing the collection of resin beads (a) into contact with an aqueous solution (b) comprising one or more dissolved (M).sub.nX.sub.q to form a mixture (b), (c) separating water and compounds dissolved in the water from the mixture (b), to form resin beads (c) and waste solution (bw); (d) bringing resin beads (c) into contact with an aqueous solution (c) comprising dissolved (M3)(OH).sub.p, to form a mixture (d).