Abstract: A method for producing a polyaddition product of isophorone diisocyanate and diols which comprises, reacting a uretidione group-containing dimer of isophoronediisocyanate, which is decomposable by heat into 98% isophorone diisocyanate, with a diol, wherein the ratio of NCO to OH groups is such that the final polyaddition product has free terminal NCO groups, or free terminal OH groups.

Abstract: The process relates to the formation of diaphragms, for example those used for alkali chloride electrolysis in an aqueous solution. The formation of a layer-type diaphragm, accreted on a hollow diaphragm support from a slurry having a high solids content of diaphragm material, is made uniform.During the accretion step, the diaphragm support is periodically lifted and lowered in the slurry (frequency 0.1-10 min.sup.-1 ; amplitude 10-100 cm; velocity 2-20 cm/sec); its topside, at the upper reversal point of the oscillating motion, has a certain spacing (10-25 cm) from the constantly measured height of the level of slurry in the accretion tank and its underside cannot reach below a minimum distance (30 cm) from the bottom of the basin. The suction pressure of the slurry through the hollow diaphragm support is maintained at a constant value and is controlled (10-500 mbar below the atmospheric pressure of the surroundings).

Abstract: Polyisocyanatoisocyanurates of the formula ##STR1## wherein the R groups may be the same or different and are aliphatic divalent radicals selected from the group consisting of divalent aliphatic radicals having the formulas ##STR2## and n is a whole or fractional number from 1 to 5, are useful as isocyanate hardeners in polyurethane resin coatings.

Abstract: The invention relates to a process for removing heavy metal ash from an aqueous soot suspension like that found in the production of synthetic gas through partial gasification of heavy oils. This soot suspension is treated initially in the standard manner with adjuvants suitable for the separation of soot and which are not miscible in water followed by separation of the aqueous phase. The process is characterized by the fact that ash components in the aqueous phase, are brought to a sedimentation stage for settling and are subsequently removed from the water circulation system.

Abstract: In a process for the trimerization of diisocyanates in the presence of a catalyst comprising quaternary ammonium salts of organic acids having the formula: ##STR1## wherein X represents the same or different radicals selected from the group consisting of C.sub.1 -C.sub.20 alkyl, C.sub.3 -C.sub.8 cycloalkyl, and C.sub.2 -C.sub.20 aralkyl; two X radicals taken together with at least one other heteroatom forming a hetero-ring and three X radicals taken together with the quaternary nitrogen atoms forming a hetero-ring through a common hetero-atom such that said heterocyclic ring structure is selected from the group consisting of triethylene diamine, methyl triethylene diamine, quinuclidine, N-methylmorpholine, N-ethylmorpholine, and N,N'-dimethylpiperazine; R is alkyl, cycloalkyl or aralkyl, R" is R or hydrogen; R+R" together form a C.sub.1 -C.sub.12 alkyl radical; R' is hydrogen, hydroxyl or a C.sub.1 -C.sub.12 alkyl radical, optionally containing a CH.sub.(3-b) Z.sub.

Abstract: Modified polyvinyl chloride is produced by suspension polymerization in the presence of monomersoluble catalysts and conventional protective colloids. After polymerization, there is added to the polymerized mixture, 0.1 to 3% by weight, based on the amount of polyvinyl chloride of the latex of a copolymer of 75-95% by weight of methyl methacrylate, 0-20% by weight of styrene, and 5-25% by weight of an acrylic acid ester of 4-8 carbon atoms in the alcohol component. Precipitation of the latex is then effected under continued agitation. Precipitation can be accomplished, for example, thermally or using coagulants. The thus-modified suspension polymer is subsequently obtained by ordinary removal by filtration and drying.

Abstract: Fine particulate expandable flame retardant styrene polymers having an improved minimum mold dwell time and reduced block shrinkage are prepared by:(a) mixing together styrene monomer or a mixture of styrene and a copolymerizable monomer with an organic halogen compound and an expanding agent in an aqueous dispersion;(b) adding before or during polymerization to the mixture of (a) from 0.0001 to 0.1% by weight of an expoxidation product of an aliphatic hydrocarbon of which the epoxidated aliphatic chain comprises from 6 to 18 C atoms, this epoxidation product being soluble in the monomers;(c) carrying out a polymerization in the aqueous suspension of (a) and (b) using radical forming initiators at temperatures of 80.degree. C.-130.degree. C. to form expandable particles;(d) pre-forming the expandable particles resulting from (c);ageing the pre-formed particles of (d); and(f) molding the pre-formed and aged particles of (e) in a pressure resistant mold.

Abstract: A process for producing a 3,3-dimethyl-2-alkoxyoxirane comprises oxidizing a 1-alkoxy-2-methylpropene with molecular oxygen in the liquid phase, at a temperature of 25.degree.-70.degree. C., optionally in the presence of an alkaline compound.

Abstract: The level of radioactivity in gypsum produced from phosphate rock can be reduced by adding to the slurry of acid and phosphate rock in the conventional process for producing phosphoric acid a combination of concentrated nitric acid or hydrochloric acid and an ammonium salt, especially ammonium nitrate or ammonium phosphate, before the precipitation of the calcium sulfate.

Abstract: A flow-promoting device in combination with a heated box tray open at the top in a reaction and degasification column in which a viscous or highly viscous liquid is flowing from an inlet end to an outlet end of the tray and in which a heating tube register is located to be completely covered by the liquid. The tube register includes a plurality of heating tubes spaced from each other, and the flow-promoting device has a bottom heating unit for the box tray positioned outside and along the bottom of the tray, a siphon plate mounted on the tray at a liquid inlet end of the tray and closely in front of the tube register, with the siphon plate having a bottom end extending to the underside of the tube register, and a weir positioned at the liquid outlet end of the box tray. The weir has a top edge extending at least to the topside of the tube register, and the spacing of the weir from the tube register is larger than the spacing of the siphon plate at the inlet end from the tube register.

Abstract: A process for producing a shelf-stable ethylene-.alpha.-olefin (diene) elastomer powder which comprises a release agent, comprising grinding crumbs or preliminarily comminuted particles of an ethylene-.alpha.-olefin (diene) elastomer having a green strength of 5-20 MPa and a Mooney viscosity ML (1+4) 100.degree. C. of 50-150, and, prior to, during or after the grinding step, adding 0.5-10 parts by weight per 100 parts by weight of the ethylene-.alpha.-olefin (diene) elastomer, of a release agent which is(a) polyethylene of a density of 0.910-0.975 g/cm.sup.3, a viscosity number of 50-330 cm.sup.3 /g and a melt index of 0.2-50 g/10 min, polypropylene of a density of 0.90-0.910 g/cm.sup.3, a viscosity number of 100-1000 cm.sup.3 /g and a melt index of 0.1-50 g/10 min, polybutene-1 of a density of 0.910-0.975 g/cm.sup.3, a viscosity number of 100-1000 cm.sup.3 /g and a melt index of 0.1-100 g/10 min, polyvinyl chloride of a viscosity number of 50-200, all having an average secondary particle size of 5-50 .mu.

Abstract: Cyclic imides of the formula: ##STR1## in which R represents a saturated or unsaturated, optionally alkyl- or alkenyl-substituted alkylene or cycloalkylene radical having 2-120 C-atoms and R' represents hydrogen or a substituent selected from the group consisting ofan alkyl radical having 1-20 C-atoms,an alkenyl radical having 3-5 C-atoms,an aralkyl radical having 7-12 C-atoms,--CH.sub.2 --CH.sub.2 --CN,--CH.sub.2 --CH.sub.2 --COO--alkyl,--CH.sub.2 --CH.sub.2 (CH.sub.3)--COO-alkylan acyl radical or--(CH.sub.2 --CH.sub.2 O).sub.n H, wherein n is 1-10are stabilizers for synthetic resins especially for polyolefins.

Abstract: Powdered coating compositions having good storage stability and particle size smaller than 0.25 mm, particularly 0.02 and 0.06 mm, based on polyesters which contain hydroxyl groups and melt between 40.degree.-120.degree. C., .epsilon.-caprolactam blocked isophorondiisocyanate adducts, and catalysts, if necessary, and customary additives, wherein isophoronediisocyanate adducts partially blocked with .epsilon.-caprolactam are used as curing agents.Methods for producing the above mentioned powdered coating compositions, wherein the polyesters containing hydroxyl groups are reacted in the melt or in solvents at temperatures of 0.degree.-150.degree. C., particularly 80.degree.-120.degree. C., with an isophorondiisocyanate adduct blocked with .epsilon.-caprolactam which contains 0.1 to 1 mole of free NCO-groups per mole of adduct and 0.4-1.1 NCO-equivalents separate to OH equivalent.

Abstract: A process for removing troublesome precipitates of condensable gases in a heat exchanger of a continuously operated low temperature installation in which gas to be cooled, such as air, which contains condensable gases at ambient temperature is passed from a warm end to a cold end of the exchanger through a storage material and over heat exchange surfaces--maintained at a temperature ranging from -165.degree. C. to -160.degree. C. at the cold end--and cold regenerator gas free of condensable gases is alternately passed from the cold end to the warm end over the storage material and heat exchanger surfaces to remove precipitates of the condensable gases therefrom in a cyclic operation, without total shut-down of the installation, involves the further step of introducing warm gas which is at a temperature of between 0.degree. C. and +110.degree. C.

Abstract: A copolymer derived from maleic anhydride and dicyclopentadiene, containing hydroxyl groups, having the formula: ##STR1## wherein R and R' may be the same or different, selected from the group consisting of H, C.sub.1 -C.sub.14 alkyl-isobutyronitrile, phenyl which is optionally substituted by halogen, C.sub.1 -C.sub.8 alkyl-substituted phenyl, C.sub.1 -C.sub.14 alkoxy-, C.sub.1 -C.sub.14 acyloxy- or halogen-substituted benzoyl, and n=3-10. The copolymer is useful for the sizing of paper.

Abstract: A process for the continuous separation of methanol and water from a feed mixture containing predominantly tetrahydrofuran admixed with water, methanol and small amounts of additional compounds, in a rectifying apparatus having at last two rectifying columns, of which two are operated at different pressures which involves feeding the raw material into a first column operated under lower pressure, and introducing the distillate from the column operated under a lower pressure to a second column operated under a higher pressure, while a product stream from the second column operated under a higher pressure is reintroduced into the first column operated under a lower pressure.

Abstract: The invention relates to a method of preventing smoldering decomposition of multiple-nutrient fertilizers containing ammonium nitrate at elevated temperatures by treatment of the granulated, dried and screened fertilizer with ammonia.

Abstract: A process of producing storage-stable urethane acryls which comprises:(A) forming a prepolymer by reacting one isocyanate group of a cycloaliphatic diisocyanate having two isocyanate groups of substantially different reactivity, with a single NCO reactive hydroxy group-containing acrylic compound which is additionally polymerizable;(B) reacting said prepolymer with a multifunctional polyol to thereby obtain a substantially NCO-free urethane acryl. Acryl urethanes produced can be used as hot melts or in mixtures with reactive diluents for coatings of plastics, metals, wood, pressboards, glass, leather, concrete, and the like.

Abstract: A method for producing a catalyst comprising phosphoric acid and a carrier, for the hydration of olefins with 2-3 carbon atoms to the corresponding alcohols, the method comprising:contacting a clay, containing essentially montmorillonite, contaminated by no more than 3% accompanying minerals and containing up to 0.5% by weight K.sub.2 O, or a mineral of the montmorillonite group, containing no potassium, but having the montmorillonite crystalline lattice, with an acid until it has an Al.sub.2 O.sub.3 content of 13-18% by weight and a surface area of 200-400 m.sup.2 /g;admixing the so-treated clay with 5-15% by weight, based on the total dry admixture, of one or more oxides of metals of Group VI of the Periodic System;adjusting the water content of the admixture to 20-35% by weight;pressing the admixture into a desired shape and calcining at 500.degree.-800.degree. C.;treating the so-formed carrier material with an acid until it has an Al.sub.2 O.sub.

Abstract: Herbicidal-substituted .alpha.-(trimethylcycloalkenyl)-N-alkylacetamides of the formula ##STR1## wherein R is a linear or branched alkyl or alkoxyalkyl radical with 1-6 carbon atoms or an allyl radical, optionally substituted with C.sub.1 -C.sub.4 alkylene groups, and X is a substituent from the group consisting of hydrogen, methyl, chlorine and bromine, in any combination, the free valences signify hydrogen and two of the methyl groups on the ring are attached to the same carbon atom, are useful pre- and post-emergent herbicides for weed control in crops.