Abstract: Processes are described which comprise: (a) providing a mixture comprising a cyclic formal and water, wherein the mixture has a cyclic formal concentration and a water concentration; (b) bringing the mixture into contact with an aqueously selective membrane; (c) creating a pressure differential across the membrane; and (d) obtaining a permeate having a higher water concentration and a lower cyclic formal concentration than the mixture, and a retentate having a lower water concentration and a higher cyclic formal concentration than the mixture.

Abstract: Processes are described which comprise: (a) providing a mixture comprising a cyclic formal and water, wherein the mixture has a cyclic formal concentration and a water concentration; (b) bringing the mixture into contact with an organically selective membrane; (c) creating a pressure differential across the membrane; and (d) obtaining a permeate having a lower water concentration and a higher cyclic formal concentration than the mixture, and a retentate having a higher water concentration and a lower cyclic formal concentration than the mixture.

Abstract: The invention relates to a method of material separation, in which a material, which comprises at least a first material component and a second material component, is introduced, together with a washing fluid, into a container with at least one sedimentation chamber and is subjected to a gravitational field, under influence of the gravitational field in the sedimentation chamber, the first material component is enriched in a sedimentation zone, which is bounded by a base, and the material with the enriched first material component is evacuated from the sedimentation zone via an opening in the base, the material with the enriched first material component being evacuated as a sediment film through the opening in the base, washing fluid flowing transversely onto the sediment film and the washing fluid flowing through the sediment film and, in the process, an at least partial displacement of the remaining second material component taking place from the sediment film.

Abstract: The present invention relates to a process and an apparatus for separating separating polymeric from one or more by-products of preparation of the polymer and a first liquid phase, wherein the solid in a first liquid phase is brought into contact with a second liquid phase and the solid is transferred into the second liquid phase. The solid is washed in countercurrent and at least partial displacement washing takes place during the washing of the solid.

Abstract: Electrically conductive compositions and method for the production and use thereof

Abstract: The present invention relates to a process for preparing mixture from a large number of components, the concentrations of the components used being capable of continuous variation over prescribed ranges in a very simple manner. For this, the mixtures are continuously prepared in a mixing assembly and continuously converted into a form which can be subjected to further processing. By way of example, the invention may be used for producing substance libraries for high-throughput screening in the plastics industry, in particular of mixtures of polymers with one another and of mixtures of polymers with added materials.

Abstract: The invention relates to a device for separating substances by means of countercurrent washing, having a container with a first end region, at which a first inlet orifice for the ingress of a substance mixture and a first outlet orifice for the egress of a substance component to be separated from the substance mixture and of a washing fluid are provided, with a second end region which is located axially opposite the first end region and at which a second inlet orifice for the ingress of the washing fluid and a second outlet orifice for the egress of a further substance component of the substance mixture and of the washing fluid are provided, and with a displacement region which is provided between the first end region and the second end region, the displacement region merging into the second end region by a transitional cross section.

Abstract: The present invention relates to a process for separating a dissolved polymer from solids, wherein the solid is separated off by sedimentation and the sedimented solid is washed in countercurrent with a solvent. The present invention further relates to a process for preparing polymers in a solvent, wherein a) a polymer having a low molecular weight is prepared in solution, b) the solid which is undissolved in the reaction mixture is separated off by sedimentation and c) the mixture which has been freed of the solid is polymerized further until a particular molecular weight has been reached.

Abstract: The present invention relates to a process and an apparatus for separating solids from a first liquid phase, wherein the solid in a first liquid phase is brought into contact with a second liquid phase and the solid is transferred into the second liquid phase. The solid is washed in countercurrent and at least partial displacement washing takes place during the washing of the solid.

Abstract: The present invention relates to a process for preparing sulfur-containing polymers from at least one sulfide and from at least one aromatic dihalogen compound in at least one solvent, where a) a mixture made from a sulfide and from a solvent is prepared in a first reaction vessel, b) the sulfide and an aromatic dihalogen compound react in a second reaction vessel to form a sulfur-containing polymer, c) the pressure in the second reaction vessel is to some extent or completely released during the reaction, and the emanating vapor mixture is brought into contact with the mixture prepared in step (a).

Abstract: The process for preparing sulfur-containing polymers, in particular polyarylene sulfides, from at least one sulfide and at least one aromatic dihalogen compound, in a solvent, is carried out in the steps: a) a mixture of aromatic dihalogen compound and sulfide is polymerized, b) aromatic dihalogen compound and sulfide are added to the polymerized mixture and c) the reaction mixture is polymerized further. The sulfur-containing polymers prepared by the process are distinguished by high purity and good mechanical properties.

Abstract: The present invention relates to a method of triboelectric separation of organic polymers and salts, specially organic polymers containing sulfur, such as polyarylene sulfides and a halogenide or a carboxylate of alkaline metals, alkaline earth metals, ammonium or substituted ammonium wherein: a) the mixture to be separated is electrically charged; b) the charged particles are moved by an electric field, preferably perpendicular to the direction of the field, and c) the particles varyingly deviated in the electric field are separated and captured.

Abstract: Metallized cation-exchange membrane The present invention relates to a membrane/electrode composite comprising a membrane comprising a polymeric cation exchanger containing carboxylic acid, phosphonic acid or sulfonic acid groups, which cation exchanger is soluble in a solvent, where on at least one side of the membrane there are applied finely divided metals which catalyze the formation of water from H.sub.2 and O.sub.2. The part of the membrane covered with metal is porous, but contains no closed pores, and the metal can also be present in the pores.

Abstract: The present invention relates to a process for preparing sulfur-containing polymers from at least one sulfide and at least one aromatic dihalo compound in a solvent, which comprisesa) reacting the sulfide with a stoichiometric excess of aromatic dihalo compound,b) largely removing the excess aromatic dihalo compound andc) further polymerizing the mixture.

Abstract: In a process for preparing aromatic sulfur-containing polymers, the polymer is formed from a prepolymer having halogen end groups. During preparation of the prepolymers, an alkali equivalent and a sulfur equivalent in a ratio of 0.5 to 1:1 is employed in the reaction mixture. The two-step process is particularly suitable for preparing polyphenylene sulfide.

Abstract: Process for the preparation of polyether-amide solutions, steam-sterilizable dialysis membranes obtainable using the polyether-amide solutions, and a process for the production of these membranes.Polycondensation of one or more dicarboxylic acid derivatives of the formula I ##STR1## with one or more aromatic diamines of the formula II ##STR2## and, if appropriate, m-phenylenediamine, in aprotic polar solvents is known.As a result of passing ammonia, in an amount sufficient to neutralize the HCl formed, into the polymer solution obtained after the end of the polycondensation and filtering off the ammonium chloride formed, it is possible to prepare neutral, salt-free and particularly storage-stable polyether-amide solutions which can be further processed to membranes without isolation of the polymer. The resulting membranes are steam-sterilizable, chemically and thermally stable and show efficiency data in the region of that of good high-flux dialysis membranes.

Abstract: A semipermeable, porous, asymmetric membrane containing a polyetheramide which contains at least one or more dicarboxylic acid derivatives and aromatic diamines having a portion. The membrane is suitable for applications where contamination by glycerol or other platicizers or pore fillers must not be tolerated, may be dried without using a pore filler such as glycerol, does not collapse upon drying, and are sufficiently hydrophobic to be wetted again after complete drying.

Abstract: A macroporous, asymmetric, hydrophilic membrane is described, which contains a copolyamide which has the following recurring structural units:(A) --OC--Ar.sup.1 --CO--and also three different structural units of those mentioned below:(B) --NH--Ar.sup.2 --NH--(C) --NH--Ar.sup.3 --NH--(D, E, F) --NH--Ar.sup.2 --Z--Ar.sup.3 --NH--where the symbols Ar.sup.1, Ar.sup.2, Ar.sup.3 and Z have the following meaning:Ar.sup.1 is a 1,4-phenylene or another bivalent C.sub.6 -C.sub.r aromatic or heteroaromatic radical in which radical the bonds are in para or comparable coaxial or antiparallel position, Ar.sup.2 and Ar.sup.3 are 1, 2 phenylene, 1,3-phenylene or 1, 4-phenylene radicals and Z is one of the following bivalent radicals --O--, --CH.sub.2 --, --C(CH.sub.3).sub.2, --C(CF.sub.3).sub.2 --, --SO.sub.2 --, --NHCO--, or --O--Ar.sup.2 --O--.

Abstract: Semipermeable membranes of homogeneously miscible polymer alloys and a process for their preparation. In particular, semipermeable membranes of homogeneous polymer alloys which contain sulfonated, aromatic polyether ketones and at least one polyamide as the main constituents, wherein the polyamide is a completely aromatic polyamide.