Abstract: The subject of the invention is a conveyor belt comprising an outer polyamide layer and an inner layer of a thermoplastic block polymer, intended to be used in particular in the food or agri-foodstuff industry.

Abstract: The invention relates to the preparation of alkanesulphonic acids by photo-oxidation of dialkyl disulphides.The procedure is carried out in solution in an alcohol using a light source irradiating between 200 and 320 nm.

Abstract: Disclosed are elastomer-coated mineral particles which are characterized by being in the form of individual granules. The disclosure also relates to a process for preparing the said particles, the said process being characterized in that it consists of the following: a) Causing the mineral particles to react with at least one binding agent which includes at least one polyoxyethylenic sequence, and with at least one elastomer latex; b) Separation of the liquid phase from the particles; c) Drying of the said particles. The utilization of the said particles for the reinforcement of thermoplastic polymers and thermoplastic polymers reinforced with the mineral particles according to this invention are likewise disclosed.

Abstract: The invention relates to reinforcing compositions for thermoplastic polymers which have improved anticaking and flow properties, which include an impact additive and a synergic combination including a micronized silica and at least one calcium salt.These compositions are very particularly suitable for the reinforcement of PVC.

Abstract: Gamma-aluminum oxynitride ground powders, white in color and well suited for conversion into optically transparent ceramic shaped articles, 100% of the particles of which being less than 10 .mu.m in size and exhibiting a transmittance of at least 8%, are prepared by grinding particulate gamma-aluminum oxynitride agglomerates having a porosity of greater than 75%, such agglomerates themselves being produced by interreacting dry powdery admixture of aluminum nitride, alpha-alumina, and an alumina of high specific surface area or precursor thereof.

Abstract: An initiation system for the anionic polymerization of (meth)acrylic monomers and, optionally, nonacrylic vinyl monomers is disclosed. The initiation system comprises (1) a functional initiator and (2) an alkali metal alcoholate having the formula R'OM', in which M' is an alkali metal and R' is a group R.sup.1 (OR.sup.2).sub.m where R.sup.1 is a C.sub.1 -C.sub.6 alkyl or arylalkyl radical, R.sup.2 is a C.sub.2 -C.sub.4 alkylene radical and m is equal to 1, 2 or 3. The initiation system is applied to the formation of (meth)acrylic homopolymers and block copolymers of (meth)acrylic monomers and, optionally, nonacrylic vinyl comonomers.

Abstract: Separation of 1,1-dichloro-1-fluoroethane (141b) from lower boiling components contained in a crude 141b feed stream mixture by adding the feed stream mixture, and, based upon the weight of 141b in the feed stream mixture, between 100 and 300 ppm of a component that will inhibit formation of 1,1-difluoro-1-chloroethane into a feed line of a distillation column operated at between 3 and 165 psig pressure with a temperature between 100.degree. F. and 250.degree. F. in the bottom reboiler section of the column.

Abstract: Poly(alkyl (meth)acrylates) are inexpensively prepared, even on an industrial scale, by anionically polymerizing at least one alkyl (meth)acrylate monomer in the presence of a lithium-based initiator and in a liquid solvent medium in which the solubility parameter .delta. is less than 20, said initiator comprising an alcoholate having the formula ROLi, wherein R has the formula R.sup.1 (OR.sup.2).sub.m, in which R.sup.1 is a linear or branched alkyl radical having from 2 to 4 carbon atoms, R.sup.2 is a linear or branched alkylene radical having from 2 to 4 carbon atoms, and m is 1, 2 or 3.

Abstract: The invention relates to the purification of pentafluoroethane (F125) containing chloropentafluoroethane (F115) by vapor-phase catalytic hydrogenolysis.A catalyst based on palladium deposited on aluminium trifluoride is employed.

Abstract: A diblock copolymer obtained by polymerizing acrylic, methacrylic or nonacrylic vinyl monomers in the presence of a polymerization initiating amount of an initiation system including (1) at least one functional initiator and (2) an alkali metal alcoholate. The alcoholate has the formula:R'OM'in which M' is an alkali metal and R' has the formula:R.sup.1 (OR.sup.2).sub.min which R.sup.1 is a linear or branched alkyl radical containing from 1 to 6 carbon atoms or an arylalkyl radical, R.sup.2 is a linear or branched alkylene radical containing from 2 to 4 carbon atoms, and m is the integer 1, 2 or 3.

Abstract: The invention relates to a continuous process for the preparation of aluminum nitride by the carbonitriding of alumina. According to this process, a reaction that uses alumina, carbon, and a resin that generates carbon by pyrolysis is performed in a methodical reactor. The invention relates to a continuous process for the preparation of aluminum nitride by the carbonitriding of alumina.

Abstract: Bifunctional primer naphthalene compounds having the formula: ##STR1## wherein M" is an alkali metal, preferably sodium or lithium, and R.sup.1 and R.sup.2 are, e.g., alkyl radicals, are prepared from corresponding 1,5-diethenylnaphthalene derivatives, and are well suited for the improved anionic polymerization of diene, vinylaromatic and/or (meth)acrylic monomers.

Abstract: The invention relates to a translucent and flexible polyamide-based composition, which is easy to process, in particular by extrusion, comprising: (A) from 50 weight-% to 95 weight-% 1) of at least one polyamide resin (I), 2) of various additives (IV) such as stabilizers, mould-release agents, lubricants, crystallization accelerators, pigments, organic and/or inorganic fillers or dyes, or antioxidizing agents, 3) optionally of at least one plasticizing agent (V), and (B) from 5 weight-% to 50 weight-%: (a) of at least one ethylene-alkyl (meth)acrylate-unsaturated dicarboxylic acid anhydride terpolymer (II), (b) of at least one ethylene-alkyl (meth)acrylate copolymer (III) with 1/30.ltoreq.(b)/(a).ltoreq.2. In accordance with the present invention, the flexural modulus of the composition, measured according to ISO standard 178, is less than or equal to 2/3 of the flexural modulus of the PA resin (I) alone and is strictly less than 750 MPa.

Abstract: Anionic waterborne polyurethane dispersions made using hydroxyl terminated polybutadiene resins and use of the dispersions to make films and adhesives.

Abstract: This process for the preparation of isobornyl (meth)acrylate by reaction of (meth)acrylic acid with camphene consists in blending the reactants in a blending tank and in placing the mixture in contact with the catalyst in a cartridge which is separate from the blending tank.Single figure.

Abstract: The aldolization is characterized by the use of a solid basic catalyst which has the following general formula?(Mg.sup.2+).sub.1-x (Al.sup.3+).sub.x (OH.sup.-).sub.2 !.sup.+x ?(OH.sup.-).sub.x (H.sub.2 O).sub.n !.sup.-x (II)wherein 0.20.ltoreq.x.ltoreq.0.33 and n has a value of less than 1. This catalyst has a defined crystal structure similar to that of hydrotalcite or, alternatively, of meixnerite. Also disclosed are processes for the preparation of the catalyst.

Abstract: The invention relates to the gas-phase hydrogenolysis of chlorofluorocarbons or of chlorofluorohydrocarbons in the presence of a palladium-based catalyst deposited on a support in which sulfur is incorporated into the catalyst in order to stabilize the catalytic activity.

Abstract: This invention relates to compositions resulting from the reaction, in aqueous phase, of aluminum hydroxide, of alkali metal cation hydroxide and of calcium or strontium hydroxide. The addition of such a composition to PVC resins or to olefinic resins from Ziegler catalysis prevents the degradation of these resins under the effect of light or of heat, in particular during extrusion.

Abstract: The invention concerns the anionic polymerization of alkyl methacrylate in the presence of a priming system. The priming system comprises an organolithium primer and an organic compound of aluminum and pyridine. This priming system allows better polymerization control.

Abstract: Living random (meth)acrylic copolymers, facilely converted into random co(meth)acrylates and block copolymers thereof, comprise the anionic copolymerizates of at least one comonomer A with at least one comonomer B selected from among the (meth)acrylates and maleimides, at least one of the comonomers A and B comprising a (meth)acrylate, in the presence of (i) at least one alkali or alkaline earth metal, mono- or difunctional initiator and (ii) at least one ligand, for example a nonnitrogenous macrocyclic complexant, e.g., a crown ether, or an alkali metal alcoholate.