Abstract: Compositions based on ?-caprolactone polymer, comprising at least one ?-caprolactone polymer and calcium carbonate. Process for preparing these compositions, which are used for manufacturing articles, in particular films, preferably obtained by extrusion blow-moulding or by flat-die extrusion.

Abstract: Process for producing polyolefins, comprising the following steps: a) grafting of acid groups onto polyolefins by means of a graftable monomer bearing at least one functional group chosen from a carbonyl and an acid anhydride, optionally in the presence of another graftable monomer bearing a vinyl unsaturated group and, optionally, one or more aromatic rings; b) purification, consisting in removing at least some of the graftable monomer bearing at least one functional group chosen from a carbonyl and an acid anhydride that has not reacted with the polyolefins; c) neutralization of the acid groups by at least one neutralizing agent. Polyolefin obtained.

Abstract: The dialkyl peroxydicarbonates with short alkyl chains, preferably diethyl and diisopropyl peroxydicarbonates, are used for the aqueous suspension polymerization of vinyl chloride, in the form of a solution in a dialkyl alkanedicarboxylate which is liquid and insoluble in water. The preferred solvents are hexanedicarboxylates (adipates) derived from adipic acid and from C6-C10alkanols. The peroxydicarbonate concentration of the said solutions is generally 15-40% by weight. The process according to the invention produces vinyl chloride polymers of improved quality resulting in shaped articles exhibiting markedly fewer fisheyes. The invention also relates to a two-stage process for the manufacture of a solution of dialkyl peroxydicarbonates with short alkyl chains which is particularly suited for the aqueous suspension polymerization of vinyl chloride.

Abstract: The present invention relates to a water-based polymer composition, comprising: at least one polymer (P) comprising recurring units (R1), from 0 to at most 25% mol of said recurring units (R1) comprising a carboxylic acid group (in acid or salt form); at least one aromatic polyamic acid (A) comprising recurring units, more than 50% mol of said recurring units comprising at least one aromatic ring and at least one amic acid group and/or imide group [recurring units (R2)], more than 50% mol of recurring units (R2) comprising at least one amic acid group, part or all of the amic acid groups being neutralized by at least one basic compound (B); water; optionally, at least one organic solvent (S) of the aromatic polyamic acid (A), in an amount of less than 20% wt with respect to the weight of the aromatic polyamic acid. The polymer (P) is preferably a fluoropolymer; it can be either a partially fluorinated fluoropolymer, such as ECTFE, or a perfluorinated fluoropolymer such as TFE polymers.

Abstract: Vinylidene fluoride polymers, characterized in that they are thermoplastic vinylidene fluoride/chlorotrifluoroethylene/hexafluoropropylene terpolymers and in that they contain at least 70% vinylidene fluoride, process for obtaining them and use thereof.

Abstract: Process for manufacturing hollow plastic bodies, especially motor-vehicle fuel tanks, from an extruded parison of closed cross section, in which at least one cut is made in the parison which is then formed by molding.

Abstract: Process for manufacturing an oxirane by reaction between an olefin and hydrogen peroxide in the presence of a catalyst and an organic diluent, according to which the hydrogen peroxide is an aqueous hydrogen peroxide solution obtained by extraction, with substantially pure water, of the mixture derived from the oxidation of at least one alkylanthrahydroquinone, without subsequent washing and/or purification treatment.

Abstract: 1,1-Difluoroethane containing less than 10 mg/kg of vinyl chloride is obtained by treatment, with hydrogen fluoride, of a crude 1,1-difluoroethane containing less than 1 mol of hydrogen chloride per mole of 1,1-difluoroethane.

Abstract: System and for sealing an opening of a plastic tank with a multilayer wall by means of a multilayer plate itself constituted by a polymer structure including at least one internal barrier layer and an exterior layer compatible with the exterior layer of the tank wall. The multilayer plate is welded over an opening in the tank and the plate and the wall of the tank are superimposed so that the number of superimposed layers is equal to the sum of the number of layers in the plate and the number of layers in the wall of the tank.

Abstract: Hydrofluorination catalyst based on a chromium oxide which is poor in ammonium salts.

Abstract: Process for manufacturing oxirane by reaction of an olefin with a peroxide compound in the presence of a catalyst and a solvent in at least two reactors arranged in series, each of which contains a portion of catalyst, according to which the peroxide compound is introduced only into the first reactor, the subsequent reactor(s) not being fed with fresh peroxide compound, but only with the peroxide compound which is present in the medium obtained from the preceding reactor and which was not consumed in this preceding reactor.

Abstract: Process for manufacturing an oxirane by reaction between an olefin and hydrogen peroxide in the presence of a catalyst and an organic diluent, according to which the hydrogen peroxide is an aqueous hydrogen peroxide solution obtained by extraction, with substantially pure water, of the mixture derived from the oxidation of at least one alkylanthrahydroquinone, without subsequent washing and/or purification treatment.

Abstract: Process for manufacturing a plastic fuel tank from two shells formed by molding, which are joined together, at least one shell being produced by compression-molding a portion of a plastic sheet between a mold and a punch and by the remaining portion of the sheet being blow-molded in the region not compression-molded.

Abstract: The invention relates to a process for the preparation of chloro-1-fluoroethane and 1,1-difluoroethane by reaction of vinyl chloride with hydrogen fluoride, in organic solvent consisting of at least one saturated halogen-containing hydrocarbon.

Abstract: Catalytic composition comprising copper chloride, magnesium chloride and potassium chloride deposited on an alumina, which may be used in particular for the oxychlorination of ethylene into 1,2-dichloroethane. In the processes for the oxychlorination of ethylene in oxygen in a fluid bed, this catalytic composition makes it possible to obtain an excellent yield of 1,2-dichloroethane without causing the deposition of soiling material on the surface of the bundle of tubes of the heat exchanger located in the reactor.

Abstract: The invention concerns thermoplastic aliphatic polyester compositions characterized by a melt flow index (RMFI) ranging between 1.1 and 2.5. The invention also concerns a method for preparing said compositions which are used for making films, foams, flasks or thermoformed products. The resulting films obtained from said compositions are used for making litter bags, films for agricultural use, packaging films, shrouds, diaper drawers and adhesive films.

Abstract: The invention relates to a process for the preparation of an aqueous dispersion of halogenated vinyl polymers by polymerization, according to which, after polymerization, a basic agent is added in an amount such that the pH of the aqueous dispersion is less than approximately 5. The invention also relates to the aqueous dispersion obtained, which can be coated onto polymeric substrates made of paper or of regenerated cellulose.

Abstract: Polymer compositions based on vinylidene fluoride resins which are particularly suitable for the manufacture of pipes for conveying hot hydrocarbons under pressure, comprising by weight; (A) from 60 to 80% of at least one PVDF homopolymer; (B) from 20 to 40% of at least one thermoplastic copolymer of vinylidene fluoride (VF2) and of at least one other fluoromonomer (for example hexafluoropropylene, chlorotrifluoroethylene or trifluoroethylene), containing approximately from 5 to 25% of this other monomer; and (C) a plasticizer, in proportions of 5 to 20% [relative to the total weight of the polymers (A) and (B)], preferably dibutyl sebacate or a polyester of molecular mass of between 1500 and 5000.

Abstract: Functional trifluorovinyl monomers, process for the copolymerization of trifluorovinyl monomers with fluoroolefins and use of these trifluorovinyl monomers in forming fluoroelastomers. Copolymers resulting from this copolymerization process and process for crosslinking these copolymers.

Abstract: Perfluorobutyl methyl ether forms azeotropic or pseudoazeotropic compositions with esters. These compositions can be used in particular as solvent for cleaning and defluxing electronic components, for degreasing metals, for removing water adsorbed at the surface of solids and for fixing a toner to a printing substrate.