Abstract: A method for introducing gases into liquids, wherein a stirred kettle is used which has the form of a cylindrical vessel in which the length/diameter ratio should be at least 1; and wherein the stirred kettle is filled to a level of more than 70% with the liquid into which gas is to be introduced, the gas feed rate is adapted to the absorption capacity of the liquid, and the stirrer speed is adjusted such that the largest coherent amount of gas is 10% of the volume of the stirred kettle.

Abstract: A process for the purification of hydrochloric acids contaminated with C.sub.1 -chlorinated hydrocarbons involves the controlled use of a distillator column. The contaminants are removed by stripping with HCl gas, the stripping being performed in a bubble column.

Abstract: A polyurethane coating composition comprising:(a) a synthetic organic polymer containing at least two hydroxyl groups,(b) a polyisocyanatoisocyanurate having the formula: ##STR1## wherein the R groups may be the same or different and are selected from the group consisting of divalent hydrocarbon radicals having the formulas: ##STR2## and n represents a whole or a fractional number from 1 to 5, and (c) optionally, conventional auxiliary agents selected from the group consisting of solvents, dispersing agents, pigments, fillers, and spreading agents, can be subjected to cold or hot curing, and provides a cured coating composition having good resistance to thermal oxidation, good solvent resistance and good mechanical film properties.

Abstract: The invention relates to a process for introducing gases into liquids, a stirred kettle being used which has the form of a cylindrical vessel in which the length/diameter ratio should be at least 1. The stirred kettle is filled to a level of more than 70% with the liquid into which gas is to be introduced, the gas feed rate is adapted to the absorption capacity of the liquid, and the stirrer speed is adjusted such that the largest coherent gas space amounts, as a maximum, to 10% of the volume of the stirred kettle.

Abstract: The invention relates to a process for purifying polyphenylene oxides obtained by interruption of the copper-amine catalyzed polycondensation of di-ortho-substituted phenols, where in said process the reaction mixture is subjected to a "reaction-extraction" (i.e., an extraction which is accompanied by reaction) with water or stream, at a temperature of 60.degree. to 150.degree. C. It is particularly advantageous if the starting mixture in the inventive process comprises a solution of the polyphenylene oxide wherein the reaction has been interrupted by water and CO.sub.2, which solution is mixed into a toluene/water mixture; and further if the "reaction-extraction" is carried out in the presence of an alkanolamine and a stabilizer.

Abstract: The invention relates to thermoplastic compositions comprising mixtures of(A) 100 parts by wt. polyphenylene ethers;(B) 2-40 parts by wt. polyoctenylene; and(C) the following additives in amounts given as wt. % of the overall molding or forming composition:up to 50 wt. % reinforcing and filling materials;up to 60 wt. % condensation polymers;up to 15 wt. % flame retardants; andup to 5 wt. % other additives.The invention further relates to methods for producing such mixtures in the molten state and in solution.

Abstract: The separation of homozeotropic mixtures of a paraffin or paraffins of 6-14 carbon atoms and an alcohol or alcohols of 4-8 carbon atoms is conducted in two rectification steps. In a first step, rectification is carried out in the presence of water as the azeotropic agent, and the resultant distillate, after condensation, is separated into two liquid phases. The thus-obtained organic phase is rectified in a further step without the addition of water, and the head product consisting of an alcohol/paraffin mixture is recycled into the first step. The paraffin or paraffins and the alcohol or alcohols are obtained in the lower section of the individual rectifying step or steps. The water which may be present in the starting mixture is removed from the cycle. Low-boiling paraffins and/or low-boiling alcohols are suitable as additional azeotropic agents.

Abstract: One-component baking enamels of polyesters, containing hydroxyl groups, and polyisocyanates, wherein the polyisocyanate component consists of 2-methyl-1,5-diisocyanatopentane (MPDI) having the formula (I): ##STR1## which is blocked totally or partially by .epsilon.-caprolactam or acetoxime, or a mixture of the same with 2-ethyl-1,4-diisocyanatobutane (EBDI) having the formula (II): ##STR2## which is blocked totally or partially by .epsilon.-caprolactam or acetoxime, wherein the diisocyanate mixture of (I) and (II) has about 88 to 99% by weight of (I) and about 12 to 1% by weight of (II) and the free isocyanate (NCO) content is up to about 10% by weight.The one-component baking enamels are suitable for application to metal, glass and plastic objects and exhibit excellent flexibility and weather resistance.

Abstract: Thermoplastic compositions comprised of the following components:(A) Polyphenylene ether, in the amount of 20-90 parts by weight;(B) Styrene resins, in the amount of 5-70 parts by weight;(C) Polyoctenylenes, in the amount of 2-20 parts by weight;(D) Copolymers based on styrene and butadiene, in the amount of 0-20 parts by weight; and(E) Optionally, other additives;are disclosed.

Abstract: Decomposable organic compounds can, at times, be contained in the feedwater for steam generators; these decomposable compounds can stem from the untreated water supply or from the recondensate if the steam is utilized as heating steam for chemical plants and the condensate is recycled into the steam generator. The decomposition products can lead to damage to the material in the steam generator during long-term exposure.A partial stream of the feedwater is continuously examined for such compounds; as soon as these occur, they are disintegrated in the partial stream by UV light. The decomposition products are detected by measuring conductivity and/or by means of ion-sensitive electrodes. This measuring process works very rapidly and is highly sensitive, making it possible to consistently recognize contaminated water quantities and then to remove same in a controlled fashion from the feedwater stream for the steam generator or to process same into unobjectionable feedwater.

Abstract: The present invention relates to a method of manufacturing sealing compositions for electric wires, wherein one mixes together a filler (comprised chiefly of an alkaline earth carbonate), a binder component, and possibly additives of the type common in the art.The binder component is a combination of two binders: binder I is a homopolymer of 1,3-butadiene or a copolymer which is essentially obtained from 1,3-butadiene; and binder II is a polymer based on 1,3-butadiene and having laterally extending succinic anhydride groups.The sealing compositions are distinguished by good processibility and high dielectric strength.

Abstract: A process for controlling bead size in the production of expandable styrene polymers by suspension polymerization is carried out by adding protective colloids to the aqueous phase before polymerization begins, such protective colloids being used which are homogeneously soluble in water over the entire temperature range from 25.degree. to 125.degree. C. and in which the concentration range being employed shall not lower the boundary surface tension water/styrene below 18 N/mm.sup.2. Lastly, the protective colloids are selected according to their molecular weight and the weight ratio of aqueous to organic phase lies in the range of 0.9:1 to 1:1.25, preferably in the range of 1:1. A grain spectrum is maintained predominantly greater than 0.41 to less than 2.5 mm by varying the molecular weights of the protective colloids.

Abstract: The invention relates to a headlamp reflector for an automobile vehicle manufactured by injection molding according to the coinjection process using poly(alkylene terephthalate) having a viscosity number (DIN 16,779) of between 60 and 180 cm.sup.3 /g. It is characterized by the fact that the core contains some 15 to 75% by weight of hematite, at least 75% of the hematite having a particle size less than 70 .mu.m. Good mechanical strength and good behavior in respect of temperature.

Abstract: A herbicidal compound, and a method of use therefor, for the selective treatment of useful plant cultures, having a broad spectrum of activity against weeds and noxious grasses in pre-emergence and/or post-emergence periods having the formula: ##STR1## wherein R.sub.1 is a straight-chain or branched-chain alkyl, alkoxy, alkoxyalkyl, or alkylol radical having less than a total of 15 oxygen and carbon atoms combined, or a hydrogen atom; (R) is a lower alkyl group; A is --CH.sub.2 -- or --CH.sub.2 CH.sub.2 --; with the proviso that n is 0-6, when A is --CH.sub.2 --, and n is 3-6, when A is --CH.sub.2 CH.sub.2 --; and wherein the substituents (R) on the cycloalkyl ring are identical to or different from each other.

Abstract: A method of separating pyromellitic acid dianhydride from the reaction gas obtained from the gas phase oxidation of 1,2,4,5-tetraalkylbenzene with an oxygen bearing gas in a closed gas circulatory system, comprising, (a) desublimating pyromellitic acid dianhydride by contacting the product gas obtained from said gas phase oxidation reaction with a cold, oxygen bearing gas, (b) catalytically burning the byproducts in the waste gas obtained from the desublimation step, and (c) recirculating a proportionate amount of the byproduct free waste gas to the oxidation reactor for the gas phase oxidation reaction.

Abstract: In a direct-current-operated, gas-vortex stabilized high-voltage arc furnace with hollow electrodes and a vortex chamber, the gas to be heated is blown in tangentially to the common axis of the electrodes. In the hollow electrodes, the ratio of the internal diameter of the cathode to that of the anode is 1.6 to 2.5, and the spacing between the electrodes is 0.9 to 0.7 times the internal diameter of the cathode. In the method of operation of the arc furnace, the momentum flow of gas to be heated is at least 10 kg m/s.sup.2, the gas entering into the vortex chamber is at a gas velocity of at least 10 m/s and pressures in the vortex chamber range from 1.5 to 10 bar (absolute).

Abstract: Block copolyester amides having improved properties are applied as thermoplastic adhesives to textiles. Their melting points are between 80.degree. and 135.degree. C. and the block copolyester amides are prepared by polycondensing:(A) 60 to 95% by weight of a block polyester having terminal hydroxy groups and consisting of at least 50 molar % of the acid proportion of terephthalic acid and 40 to 90 molar percent of an alcohol proportion of 1.4-butanediol and 60 to 10 molar percent of 1.6-hexanediol, wherein up to 10 molar percent referred to 1,6-hexanediol can be replaced by aliphatic diols with longer chains; and(B) 40 to 5% by weight of a block polyamide dicarboxylic acid having a mean molecular weight M.sub.n between 1,000 and 8,000 and obtained from omega-amino-carboxylic acids or lactams having 6 to 12 carbon atoms or their mixtures with aromatic or aliphatic dicarboxylic acids.

Abstract: The catalytic cobalt compound used in the reaction of olefins with carbon monoxide and water or alkanols which employs an oxidizing treatment is reprocessed according to the present invention. This reprocessing includes in a first embodiment treating the cobaltic residue obtained as the distillation sump product with water and a carboxylic acid having 1 to 4 C atoms. The phases generated are separated and cobalt is recovered from the carboxylic acid/water phase in the form of the corresponding carboxylic acid salt. Where appropriate, the corresponding carboxylic acid salt is transformed into another carboxylic-acid salt.A second embodiment includes the steps of hydrogenating the cobalt containing residue obtained as the distillation sump product, separating the metallic cobalt which is obtained, reacting the metallic cobalt with an acid and where appropriate converting the cobalt salt so obtained into another cobalt salt.

Abstract: A separation of mixtures of water and 2,6-dimethylmorpholine is carried out by rectifying the mixtures at a pressure at the head of the column between 6 and 150 mbars. The separated 2,6-dimethylmorpholine has a maximum water content of 500 ppm by weight and it is possible to achieve for a corresponding design of the rectification water contents of less than 1 ppm by weight of dimethylmorpholine.

Abstract: Copolyamides based on dicarboxylic acids, diamines and omega amino carboxylic acids or lactams are used as thermoplastic adhesives to heat-seal especially siliconized textiles. The copolymers used consist of 20 to 80% by weight of one or more aliphatic omega amino carboxylic acids or lactams having 6 to 12 carbon atoms in the chain and 80 to 20% by weight of equimolar mixtures of one or more aliphatic dicarboxylic acids having 6 to 12 carbon atoms and aliphatic alpha-omega diamines and possibly cycloaliphatic diamines having 6 to 12 carbon atoms, at least 30% by weight of these diamines consisting of singly branched aliphatic diamines having 6 carbon atoms.