Hoechst Aktiengesellschaft

Polyplastics Co., Ltd.

Ticona Gmbh

Dietrich Fleischer

Andreas Schleicher

Heinz Strutz

Jurgen Kulpe

Kaoru Yamamoto

Gerhard Reuschel

Johannes Brandrup

Toshiro Murao

Klaus Kohlhepp

Ju/ Rgen Kulpe

Michael Hoffmockel

Georg Frank

Karl-Friedrich Muck

Gunter Sextro

Helmut Schlaf

Shuichi Chino

Hans-Dieter Sabel

J Urgen Kulpe

Wolfram Busch

Eckhard Weber

Makoto Kamiya

Andreas Kirst

Peter Christ

Nagayoshi Maeda

Oxidation product of polyarylene sulfides comprising recurring units of the formula

Oxidized polyarylene sulfides

Filter material and method of removing oxides of nitrogen from gases and

Process for oxidizing a polymer containing thioether groups, in which the polymer in solid form in a suspension medium is oxidized with ozone. The polymer obtained is suitable for the production of functional parts on which high demands are made.

Oxidation of polyarylene sulfides

A filter material based on a polyarylene thioether having repeating units of the formula

Ter material and process for removing ozone from gases and liquids

In the process for the preparation, with simultaneous end group stabilization, of polyacetal copolymers in a homogeneous phase and working up thereof, cyclic formaldehyde oligomers are copolymerized with cyclic acetals in the presence of an initiator in a polymerization reactor and immediately thereafter the initiator is deactivated by addition of basic substances, the unstable chain ends being degraded down to 0.01% to 1% in the presence of residual monomer, the product losing the majority of the residual monomer at the reactor outlet by letting down into a pelletizing device and the residual monomer which remains and the impurities dissolved in the product being removed by extraction with solvents and the product being pelletized, after drying and stabilization.

Process for the preparation of polyacetal copolymers

A moulding composition based on linear polyoxymethylene copolymers and customary additives with a melt index MFI (2,16 kg, 190.degree. C.) of .ltoreq.0,8, preferably .ltoreq.0,5 and especially .ltoreq.0,2 g/10 min has an extraordinary high toughness, which eliminates an addition of elastomer modifiers. In its preparation Lewis acids or protonic acids are used as initiators.

Polyacetal molding materials having high impact resistance, a process

Process for preparing a polyarylene sulfone by oxidizing a polyarylene thioether in acetic acid with hydrogen peroxide, the reaction being carried out in the presence of catalytic amounts of concentrated sulfuric acid and/or with the addition of equilibrium per-acids. The reaction products are suitable for producing molded parts having high temperature resistance and high resistance to chemicals.

Process for oxidizing polyarylene compounds containing thioether groups

Polyarylene thioethers having recurring units of the formula

Two-stage oxidation of polyarylene sulfides

A process for efficiently producing a hollow molding or a sheet- or rod-shaped molding includes subjecting a composition containing a polyoxymethylene copolymer resin having substantially a linear molecular structure and a melt flow index (MI) value (190.degree. C., 2160 g load) of 0.1 to 2.0 g/10 min to blow -molding or extrusion-molding operations. The preferred polyoxymethylene copolymer is prepared by copolymerizing trioxane as the principle monomer with a cyclic ether or cyclic formal comonomer in the presence of 1.times.10.sup.-3 to 1.times.10.sup.-2 molar % of a boron trifluoride catalyst or a coordination compound thereof, while regulating the chain-terminating or chain-transferring impurities in the reaction system to 1.times.10.sup.-2 molar % or less, and then cooling the product obtained to a temperature of 45.degree. or below within 30 seconds so as to deactivate the catalyst.

Method of blow or extrusion molding polyoxymethylene resin

Filter material and process for removing ozone from gases and liquids

A polyacetal molding composition comprising, as the active additive, at least one a) ester of long-chain monocarboxylic acids (C.sub.22 to C.sub.34) with mono- or polyhydric alcohols (C.sub.2 to C.sub.8), in the presence or absence of alkali metal and/or alkaline earth metal salts of the carboxylic acids mentioned, and/or b) polyethylene wax, is distinguished by a reduced tendency toward melt fracture. Such molding compositions can advantageously be employed in the production of shaped articles which show no undesirable defects in the surface.

Polyacetal molding compositions and their use

A thermoplastic molding composition comprising (A) from 20 to 70% by weight of polyphenylene sulfide, (B) from 5 to 20% by weight of ultrahigh-molecular-weight polyethylene, (C) from 10 to 40% by weight of a fibrous reinforcing agent, (D) from 10 to 40% by weight of an inorganic filler, and (E) from 0 to 1% by weight of a lubricant and/or other additives is used to produce moldings, fibers and films having particularly good wear properties.

Polyphenylene sulfide-based thermoplastic molding composition of high

Processes for producing a polyoxymethylene copolymer includes forming a crude polyoxymethylene copolymer by subjecting a reaction system containing trioxane, a cyclic ether or cyclic formal comonomer, and a catalyst (e.g., boron trifluoride or a coordination compound thereof) to copolymerization reaction conditions. During copolymerization, both the total content of impurities and catalyst in the copolymerization reaction system are adjusted. In this regard, the impurities content (i.e., those compounds which form unstable end groups in the polyoxymethylene copolymer and/or those compounds having a chain-terminating or chain-transfer function) in the copolymerization reaction system is adjusted to 1.times.10.sup.-2 mole percent or less based on the total monomer amount, while the the content of the catalyst in the copolymerization reaction system to between 1.times.10.sup.-3 to 1.times.10.sup.-2 mole percent based on the total monomer amount. Immediately after copolymerization has been completed, the crude polyoxymethylene copolymer is quenched to a temperature of 45.degree. C. or less within 30 seconds after completion of copolymerization. Quenching of the crude polyoxymethylene copolymer is preferably simultaneously accompanied by deactivation of the catalyst by bringing the crude polyoxymethylene copolymer immediately following completion of copolymerization into contact with a cold liquid which contains a catalyst deactivator.

Process for producing polyoxymethylene copolymer having reduced amount

Thermoplastic molding composition composed of A) 50 to 95% by weight of polyoxymethylene, B) 5 to 50% by weight of a rubber-elastic graft copolymer and optionally customary additives, in which the component B) is composed of a rubber-elastic core based on at least one polydiene, which is at least partially crosslinked, and at least one hard graft shell and has a bimodal particle size distribution. Monomers for formation of the graft shell are styrene, (meth)acrylonitrile and/or methyl methacrylate. The moldings produced from the molding compositions possess good tough fracture characteristics even at low temperatures.

Thermoplastic polyoxymethylene molding composition of high toughness and

The invention provides finely dispersed, agglomeration-free chloropolyethylene having good rubber and anti-blocking properties. The invention provides furthermore a process for the manufacture of such a chloropolyethylene, according to which chlorination of the starting polyethylene is carried out in the presence of a dispersing agent system of poly-N-vinylprrolidone and hydrophobic silicic acid. This process allows also the use of polyethylene types having a pronounced tendency to agglomeration.

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Darmstadt, Germany

Dietrich Fleischer