Abstract: Allophanate-modified MDI which is a storage stable liquid at 25.degree. C. is produced by reacting a monoisocyanate and an organic material having at least two hydroxyl groups and a molecular weight of from about 60 to about 6,000 to form a urethane. The urethane is then reacted with and isomeric mixture of MDI in an amount such that the product isocyanate will have an NCO content of from about 12 to about 30%. The isomeric mixture of MDI is composed of 4,4'-diphenylmethane diisocyanate containing from 0 to about 60% by weight 2,4'-MDI and less than 6% by weight of the 2,2'-MDI. This allophanate-modified MDI is further reacted with an organic isocyanate-reactive material to produce an allophanate-modified MDI prepolymer containing urethane, urea and/or biuret groups having an NCO content which is generally from about 5 to about 29% by weight. The prepolymers of this invention are particularly useful in reaction injection molding processes because they give molded articles having improved flex modulus.

Abstract: Allophanate-modified 1,3-phenylene diisocyanates or 1,1-biphenyl diisocyanates or 1,1'-oxy-bis-(isocyanato benzenes) which are storage stable liquid at 25.degree. C. are made by reacting the diisocyanate and a mono-alcohol to form an isocyanate containing urethane groups. The urethane groups in the diisocyanate are then converted to allophanate groups. The resultant product which has an isocyanate group content of from about 10 to about 40% may be further reacted with isocyanate-reactive compounds to produce an allophanate-modified diisocyanate prepolymer containing urethane or urea groups having an isocyanate group content of from about 5 to about 40.0%. The liquid, storage-stable, allophanate-modified diisocyanates produced by these processes are particularly useful in the production of elastomers and flexible foams.

Abstract: Low-boiling by-products are removed from diurethanes prepared by a phosgene-free process by carrier vapor distillation using alcohol vapor, preferably the vapor of the basic alcohol found in the diurethane, as the carrier vapor. The diurethanes freed of low-boiling by-products in this manner may be thermally decomposed to produce diisocyanates.

Abstract: A process and device for foaming casings, particularly refrigerator casings, with a blowing agent which can form an explosive mixture with atmospheric oxygen during evaporation which reduce the risk of explosion by introducing inert gas into the space in which the foam is to be formed by means of a servo-controlled inlet valve.

Abstract: The present invention relates to a process for the production of hydroxyl-group-containing compounds suitable for the polyisocyanate polyaddition process from polyurea and/or polyurethane polyurea wastes by treating polyurea and/or polyurethane polyurea wastes with diols and/or polyols at temperatures from 160.degree. to 260.degree. C., the water present in the reaction vessel preferably being removed by distillation during the heating-up phase, characterized in that 1,3-dicarbonyl compounds are added to the reaction mixture before or during the reaction.

Abstract: Triisocyanates are produced by gas phase phosgenation of the corresponding (cyclo)aliphatic triamines having three primary amine groups.

Abstract: An azeotropic composition made up of from about 58 to about 77% by weight of dimethoxymethane and from about 23 to about 42% by weight of cyclopentane is used as a blowing agent in a process for the production of polyurethane foams.

Abstract: High functionality, low viscosity, light colored sucrose-based polyethers are prepared by reacting a starter mixture containing i) approximately 100 parts by weight of sucrose, ii) from about 30 to about 1000 parts by weight of a low molecular weight, relatively high valency alcohol and/or an alkoxylation product of such an alcohol and iii) an alkali metal hydroxide which has been prepared at a temperature of from about 20.degree. to about 110.degree. C. with an alkylene oxide at a temperature of from about 90.degree. to about 130.degree. C. and at a pressure of from about 0.3 to about 4 bar excess nitrogen pressure. These polyether polyols are particularly useful for the production of polyurethanes, particularly rigid polyurethane foams.

Abstract: Block copolymers represented by the formula ##STR1## are formed by contacting an ester group containing poly(aryl ether ketone) composed of the recurring units ##STR2## with a liquid crystalline polyester represented by the formula ##STR3## in which R.sub.1, R.sub.2 X.sub.2, X, Z, E.sup.1, E.sup.2 E.sup.5, w, x, y, z a, b and n each represent specified groups or values under conditions such that a transesterification reaction will occur.

Abstract: An aromatic compound is polynitrated in a continuous process in a single apparatus under adiabatic conditions in an emulsion as the reaction medium. From 1.3 to 3.5 mol of HNO.sub.3 per mol of aromatic compound are introduced in the form of a nitronium ion solution into the reactor with the aromatic compound under conditions such that an emulsion forms. The emulsion, which has a tendency to coalesce, is maintained by repeated dispersion. The first dispersion of the liquid streams to produce the emulsion takes place in less than one second. At least 20% of the total amount of HNO.sub.3 to be used should generally be present during this first dispersion. It is preferred, however, that the total amount of nitronium ion solution to be used be present at the time the aromatic compound and nitronium ion solution are first dispersed.

Abstract: A process for the decomposition of polyurethane plastic waste materials in which a compound containing at least two isocyanate-reactive hydrogen atoms (e.g., glycol) and polyurethane plastic, together with 2 to 20 times the amount of previously regenerated material, are treated in a mixing and comminution device.

Abstract: Azeotropic compositions made up of (a) from about 73 to about 88% by weight perfluorohexane and (b) one compound selected from (1) about 14 to about 27% by weight 2-methyl pentane or (2) about 13 to about 25% by weight 3-methyl pentane or (3) about 12 to about 23% by weight, provided that the sum of the weight percent (a) plus weight percent (b) is 100 percent are suitable blowing agents for the production of foams.

Abstract: A vaccine effective against S. zooepidemicus-caused infections is made by enzymatic digestion of S. zooepidemicus and subsequent detergent treatment of the product of this digestion. The antigenic material thus obtained is then combined with an appropriate adjuvant.

Abstract: Isocyanates or isocyanate mixtures which contain no appreciable amounts of color causing materials are produced by phosgenating the amine corresponding to the desired isocyanate and treating the isocyanate-containing phosgenation mixture with hydrogen in the presence of a supported catalyst. The supported catalyst is in a form such that its shortest dimension is from about 0.3 to about 3.0 mm. This catalyst has a BET surface of from about 0.5 to about 150 m.sup.2 /g. No alkali material can be present in the catalyst. These isocyanates are particularly useful for the production of light-colored foams.

Abstract: An azeotropic composition made up of from about 73 to about 87% by weight of 1,1,1,4,4,4-hexafluorobutane and from about 13 to about 27% by weight of n-pentane is used as a blowing agent in a process for the production of polyurethane foams.

Abstract: Azeotropic compositions made up of from about 65 to about 81% by weight of 1,1,1,3,3-pentafluoropropane and from about 19 to about 35% by weight of 2-methyl butane have been found to be particularly useful as blowing agents for the production of polyurethane foams.

Abstract: Aromatic diamines and polyamines are produced by a continuous process for the catalytic hydrogenation of the corresponding dinitro and polynitro compounds at elevated temperature. Heat removed from the reaction mixture may be used to produce steam with an overpressure of .gtoreq.2 bar.

Abstract: Diisocyanates containing carboxylic acid ester groups corresponding to the formula: ##STR1## in which R and R.sup.1 represent specified groups are produced by phosgenation of the corresponding diamines, optionally present in the form of an ammonium salt. These diisocyanates are useful as starting materials in the production of plastics containing urethane and/or urea groups and as starting materials for the production of intermediate products used for the production of such plastics.

Abstract: Catalysts useful for the removal of volatile sulfur compounds from industrial gases composed of an inorganic, abrasion-resistant, incombustible support which is uniformly impregnated with either (a) an oxide or hydroxide of niobium or tantalum or (b) an oxide or hydroxide of manganese and an oxide or hydroxide of hafnium, lanthanum or an element in the Lanthanide Series of Elements.