Abstract: The reaction off-gas from the synthesis of melamine consists, after separating off the melamine, mainly of ammonia and carbon dioxide, with traces of hydrogen cyanide, isocyanic acid, urea and residual melamine. To remove these trace components, the off-gas is passed over a catalyst, containing copper oxide and/or iron oxide, in the presence of steam at from 100.degree. to 500.degree. C.

Abstract: In a process for the continuous preparation of adipic acid by hydrolysis of C.sub.1 -C.sub.4 -alkyl adipates with water at an elevated temperature in the presence of a strongly acidic ion exchanger, the improvement that the esters and excess water are fed to the middle section of a column, reaction mixture is taken off at a plurality of trays of the column below the feed point, passed over a strongly acidic ion exchanger and recycled, alkanols or alkanol/water mixtures are taken off at the top of the column and an aqueous solution of adipic acid is taken off at the bottom of the column.

Abstract: N-Methyl-N-silyl-carbamates of the formula ##STR1## where R.sup.1 denotes hydrogen or unsubstituted or halogen-substituted alkyl of a maximum of 4 carbon atoms, R.sup.2, R.sup.3 and R.sup.4 are identical or different and each denotes alkyl of a maximum of 4 carbon atoms, and R.sup.5 denotes alkyl of a maximum of 4 carbon atoms or phenyl, processes for their manufacture, and their use for combating pests.

Abstract: A process for the preparation of N-(D)-ribityl-2-phenylazo-4,5-dimethylaniline (I), wherein1. in the case of pure or virtually pure (D)-ribose (III)(a) the latter is reacted with 3,4-dimethylnitrobenzene (IVa) or 3,4-dimethylaniline (IVb) and with hydrogen in the presence of a hydrogenation catalyst,(b) the resulting solution is reacted, in a conventional manner, with an acid phenyldiazonium salt solution (VI) and(c) the resulting product is isolated by crystallization, in a conventional manner, or2. in the case of crude ribose, ie.

Abstract: Amphoteric surfactant gels containing a polyoxybutylene-polyoxyethylene block copolymer which maintain their gel characteristics at temperatures below about 20.degree. C.

Abstract: 2-(N-Aryl,N-1,2,3-thiadiazolylcarbonyl)-aminobutyrolactones of the formula ##STR1## where R.sup.1 is alkyl, R.sup.2 is hydrogen, alkyl or halogen, R.sup.3 is hydrogen, alkyl or halogen, R.sup.4 is unsubstituted or substituted 1,2,3-thiadiazolyl and R.sup.5, R.sup.6 and R.sup.7, independently of one another, are hydrogen or methyl, and fungicides containing these compounds.

Abstract: Copolymers of acetylene are prepared by catalytic polymerization of mixtures of acetylene and heteroalkynes with Ziegler catalysts. The polymers may be used as pigments or as colored coatings on metal, glass or plastic.

Abstract: Pantolactone is extracted from its aqueous solutions using methyl tert.-butyl ether as the extractant.

Abstract: Certain polyoxybutylene-polyoxyethylene block copolymers and their mono or diesters are useful in a diet as hypocholesterolaemic agents.

Abstract: A process for the preparation of ethylene homopolymers, and ethylene copolymers with minor amounts of higher .alpha.-monoolefins, by polymerizing the monomer or monomers by means of a supported catalyst (1) containing a chromium-hydrocarbon complex (1.2) on an inorganic oxide carrier (1.1), wherein (1) a supported catalyst is employed which contains (1.2) a chromium-hydrocarbon complex of the formula RCrACrR, where R is a cyclic and/or open-chain hydrocarbon, or hydrocarbon radical, of 2n and 2n+1 carbon atoms respectively and having from 1 to n non-cumulated double bonds, n being from 2 to 10, Cr is chromium and A is cyclooctatetraene, a divalent n-octatetraene radical or alkyl-substituted homologs thereof, on (1.1) a particular inorganic oxide carrier, with or without (2) a co-catalyst chosen from a particular group of alkyl-aluminum compounds. The process gives polymers having a particularly broad molecular weight distribution.

Abstract: Polyisocyanurate polymers are prepared by the polymerization of organic polyisocyanates in organic solvents employing trimerization catalysts. After deactivation of the catalysts and removal of the solvents, these polymers may be dispersed in polyols which are employed for the preparation of cellular and non-cellular polyurethane products displaying improved load bearing properties.

Abstract: Polyisocyanurate polymers are prepared by polymerization of polyisocyanates in organic solvents employing trimerization catalysts. The polyisocyanates are reacted with monofunctional active hydrogen compounds prior to polymerization or subsequent to the polymerization. These polymers may be dispersed in polyols for the preparation of cellular and non-cellular polyurethane products having improved physical properties.

Abstract: The subject matter of this invention pertains to polyurethane sealant compositions which are flexible, strong, and resistant to shrinkage. The sealants are prepared by reacting a mixture of polyether polyol and inorganic filler with a polyisocyanate. The polyurethane sealants are useful for making castings, for patching, and as heat barriers.

Abstract: Fluorinated anthranilic acid and anthranilonitrile, and a novel process for their preparation by reacting 2,6-difluorobenzonitrile with ammonia and, if the acid is required, hydrolyzing the resulting 6-fluoroanthranilonitrile with a basic compound.The two novel end products are valuable intermediates for the preparation of compounds which are useful for controlling various animal pests and plant pests.

Abstract: The present invention relates to a process for the preparation of stable graft polymer dispersions having improved dispersibility by a free radical polymerization of an ethylenically unsaturated monomer under conditions of no-reflux or alternatively under conditions that do not return the evaporated monomer to the dispersion. Polyurethane foams may be prepared from these polymer dispersions.

Abstract: p-Substituted aromatic amines are prepared by reacting a p-substituted, aromatic carbamic acid ester with an aromatic amine in the presence of an aliphatic or cycloaliphatic alcohol. The aromatic amines obtainable by the process according to the invention are antiseptics and valuable starting materials for the preparation of dyes, resins, finishes, plastics, pesticides and drugs.

Abstract: Aqueous low-emulsifier dispersions of emulsion copolymers which contain, as copolymerized units,(a) from 35 to 55% by weight of butadiene,(b) from 35 to 60% by weight of styrene,(c) from 1 to 3% by weight of .alpha.,.beta.-monoolefinically unsaturated monocarboxylic acids and/or dicarboxylic acids of 3 to 6 carbon atoms,(d) from 1 to 3% by weight of amides of .alpha.,.beta.-monoolefinically unsaturated monocarboxylic acids and/or dicarboxylic acids of 3 to 5 carbon atoms,(e) from 1 to 4% by weight of N-methylolamides of .alpha.,.beta.-monoolefinically unsaturated monocarboxylic acids and/or dicarboxylic acids of 3 to 5 carbon atoms, or their alkyl ethers, and(f) from 1 to 3% by weight of acrylic acid and/or methacrylic acid monoesters of alkanediols of 2 to 6 carbon atoms,the emulsion containing, as emulsifier, from 0.1 to 0.

Abstract: An improved process for the preparation of cyclocitrals of the general formula I ##STR1## via the novel N-methylaldimines of the general formula II ##STR2## and the novel N-methylaldimines of the formula II. The cyclocitrals of the formula I are obtained in yields of 80-90%, based on citral employed. The compounds I and II are important intermediates for the preparation of fragrances and carotinoids, such as vitamin A, and products related thereto.

Abstract: The generation of tape tension, based on the capacity for elastic flow of elastomeric incompressible layers, in a tape transport apparatus employing at least one capstan in contact with supply and take-up reels of tape is accomplished by producing a higher compressive force at the point of contact between the take-up reel and the resiliently deformable peripheral portion of the capstan than at the point of contact between the supply reel and the capstan. The difference in compressive forces is brought about by an additional force which is produced by means of a drivable rotating body and is transmitted to the tape reel carriers by means of a cable which is guided over this rotating body.

Abstract: A process for coating electrically conductive objects comprisingA. immersing said object as the anode of an electric current in an aqueous polyurethane dispersion prepared by(1) forming a polyurethane solution by reacting an organic polyisocyanate in the presence of an organic solvent with(a) an acrylic ester diol having a molecular weight of between 146 and 3,000;(b) an organic polyhydroxyl compound other than (a) having a molecular weight between 400 and 5,000 selected from the group consisting of polyester, polyols, polyether polyols, polycarbonates, polylactones, and mixtures thereof; and(c) a chain extender selected from the group consisting of diols, triols, diamines, aminoalcohols, having a molecular weight between 62 and 400, water, and mixtures thereof;(2) forming an anionic polyurethane addition product by reacting said polyurethane solution with a mercaptocarboxylic acid salt in the presence of a solvent;(3) adding water; and(4) removing the organic solvent, andB.