Abstract: The present invention relates to a process for the preparation of preparation ?-alkyl-2-(trifluoromethyl)-benzyl alcohol.

Abstract: The present invention relates to a process for the preparation of 4-cyanobenzoyl chlorides of formula I through reaction of compounds of formula II with a chlorinating agent.

Abstract: The present invention relates to a process for the preparation of ?-methyl-[4-(nitro)-2-(trifluoromethyl)]-benzyl nitrate and to the ?-methyl-[4-(nitro)-2-(trifluoromethyl)]-benzyl nitrate.

Abstract: A description is given of a stabilizer composition comprising A) at least one nitrogen compound having a molecular weight of at least 150, selected from a secondary amine in which all substituents positioned ? to the amine nitrogen atom are different than hydrogen, or, derived from the secondary amine, a tertiary amine, hydroxylamine, alkoxyamine or amide; and B) at least one iron compound. The stabilizer composition optionally comprises nitroxyl radicals. It is suitable for stabilizing nonliving organic material, especially polyolefins or homopolymers or copolymers of styrene, against the effects of light, heat or oxygen.

Abstract: A process for preventing undesired polymerization is conducted by maintaining an effective concentration of a stabilizer which comprises N-oxyl radicals in a mixture containing ethylenically unsaturated compounds, wherein (i) an electronic signal which correlates with the concentration of the N-oxyl radicals in the mixture is obtained periodically or continuously, (ii) the electronic signal is compared with a reference value, and (iii) addition of a stabilizer to the mixture is controlled according to the comparison (ii). The signal is preferably obtained by ESR measurement. The process permits efficient use of the stabilizer.

Abstract: The use of amidoximes for stabilisation of ethylenically-unsaturated compounds against undesired radical polymerisation is disclosed. Combinations of amidoximes with phenol and/or phenothiazine compounds have a synergistic effect. Preferred amidoximes are nitrilotris(acetamidoxime) and nitrilotris(propionamidoxime).

Abstract: An inhibitor mixture containing, as components, a) at least one nitroxyl radical (derivative), b) at least one phenol (derivative) and c) at least one chemical compound which contains at least one phosphorus atom which has the oxidation state +3 is preferably used for stabilizing compounds capable of free radical polymerization.

Abstract: (Meth)acrylic acid is worked up in the presence of at least one stabilizer by a process in which a stabilizer-containing mixture originating from the working-up and substantially freed from (meth)acrylic acid is passed into a distillation apparatus and a stabilizer-containing low boiler stream obtained from said apparatus is recycled to the working-up.

Abstract: A process of free-radically initiated aqueous emulsion polymerization, in which monomers are polymerized in the presence of a N-oxyl radical and by means of special free-radical polymerization initiators at more than 100° C. and at pressures above the vapor pressure of the polymerization mixture.

Abstract: Styrene is recovered continuously from a styrene-containing mixture by distillation of the mixture in a cascade of n distillation columns, where

Abstract: The present invention provides a process for the free radical polymerization of one or more ethylenically unsaturated monomers, said process comprising polymerizing one or more ethylenically unsaturated monomers in the presence of one or more N-oxyl radicals of formula II, wherein X is S, NR5, O, SO or SO2, R5 is C1-C20-alkyl or C5-C8-cycloalkyl and R3 and R4 independently of one another, are C1-C4-alkyl, phenyl, naphthyl or an aromatic five-membered ring, or R3 and R4 together are —(CH2)o— and p and o, independently of one another, are an integer from 2 to 7.

Abstract: Cosmetic or dermatological preparations for avoiding or reducing skin damage by peroxides or hydroperoxides formed as a result of endogenous or exogenous factors, with a content of

Abstract: An inhibitor mixture containing, as components, a) at least one nitroxyl radical (derivative), b) at least one phenol (derivative) and c) at least one chemical compound which contains at least one phosphorus atom which has the oxidation state +3 is preferably used for stabilizing compounds capable of free radical polymerization.

Abstract: In a process for the polymerization or copolymerization of ethylenically unsaturated monomers in the presence of polymerization initiators which decompose to form free radicals in a continuously operated polymerization apparatus comprising a fresh gas feed line, a precompressor, a postcompressor, a reactor, a pressure maintenance valve, a high-pressure circuit having a high-pressure product separator and a high-pressure circulation gas return line, a product valve and a low-pressure circuit having a low-pressure product separator and a low-pressure circulation gas return line, nitrogen monoxide or oxygen is introduced as inhibitor into the high-pressure circuit, into the low-pressure circuit and/or the precompressor.

Abstract: A description is given of a stabilizer composition comprising

Abstract: In a process for stabilizing chemical compounds having at least one ethylenically unsaturated bond to undesired free radical polymerization, a nitroxyl radical and a chemical compound containing phosphorus in chemically bonded form are added to the unsaturated compound present as pure substance or as a component of a mixture.

Abstract: The invention relates to a method for polymerizing or copolymerizing ethylenically unsaturated monomers in the presence of radically decomposing polymerization initiators in a continuously operating polymerization device. Said polymerization device is composed of a fresh gas supply, a pre-compressor, a post-compressor, a reactor, a pressure maintaining valve, of a high-pressure circuit, which is provided with a high-pressure product separator and with a high-pressure circuit gas return, and of a product valve and a low-pressure circuit, which is provided with a low-pressure product separator and with a low-pressure circuit gas return. The inventive method is characterized in that nitrogen monoxide or oxygen is added in a dosed manner as an inhibitor into the high-pressure circuit, into the low-pressure circuit and/or into the pre-compressor.

Abstract: A mixture contains one or more vinyl-containing compounds as component (A) and, as a further component, a stabilizer (B) which contains one or more readily volatile nitroxyl compounds as component (b1), one or more sparingly volatile nitroxyl compounds as component (b2), if required one or more aromatic nitro compounds as component (b3) and, if required, one or more iron compounds as component (b4). Stabilizers (B) contain the components (b1) and (b2), (b1) and (b2) and (b3), (b1) and (b2) and (b4), and (b1), (b2), (b3) and (b4), and the premature polymerization of vinyl-containing compounds during their purification or distillation is inhibited by a process in which a stabilizer (B) is added or the components of stabilizer (B) are added as individual substances or in at least two groups of the components.

Abstract: An article having a metallic surface treated with polymeric complexing agent is described. Particularly suitable polymeric complexing agents are phosphonoalkylated polyethyleneimines and/or carboxyalkylated polyethyleneimines and/or vinylimidazole polymers. As a rule, the treated metallic surface forms the total inner surface or a part of the inner surface of a process apparatus or of a container. The surface is protected by the treatment, in particular from the adhesion of polymer.

Abstract: An inhibitor mixture containing, as components, a) at least one nitroxyl radical (derivative), b) at least one phenol (derivative) and c) at least one chemical compound which contains at least one phosphorus atom which has the oxidation state +3 is preferably used for stabilizing compounds capable of free radical polymerization.