Abstract: In a first stage, a heterocyclic oxygen compound is polymerized by an ionic route in a vinyl halide and, in a second stage, the vinyl halide, to which other unsaturated monomers capable of being polymerized by a radical route may be added if desired, is polymerized by a radical route in aqueous dispersion and in the presence of the polymerization mixture originating from the first stage.

Abstract: Polyacetal obtained by the polymerization of trioxane, for example, suspended in an organic solvent, in the presence of a comonomer (for example, ethylene oxide), is stabilized by hydrolysis in the heated state under pressure and then, after hydrolysis, the reaction mixture is depressurized to atmospheric pressure in order to release an aqueous phase containing the polymer and a vapor phase which contains formaldehyde and trioxane. According to the invention, the latter is recycled directly into the formaldehyde trimerization stage under reduced pressure.

Abstract: Process for the catalytic synthesis of nitrogen-containing organic compounds, comprising the reaction of carbon monoxide with at least one amino compound in a reaction mixture containing a catalyst based on selenium and a substituted pyridine. The process is particularly suitable for the synthesis of ureas and of their polymers.

Abstract: Process for the production of salt in which sodium chloride is crystallized in the form of spheres by evaporation of a sodium chloride brine and the spheres obtained are then broken up. The salt produced by the process is particularly suitable for the food industry.

Abstract: A metal alcoholate is treated with a quantity of water such that the molar ratio of the quantity of water to the quantity of metal alcoholate is lower than the valency of the metal in the alcoholate.

Abstract: A stabilized composition of 1,1,1-trichloroethane comprising an epoxide compound, a nitro compound, and a furan compound.

Abstract: Stabilized compositions of 1,1,1-trichloroethane containing a mixture of two dialkoxyalkanes such as dimethoxymethane and 1,2-dimethoxyethane and at least one acid acceptor such as epoxybutane, and, if appropriate, a nitrated derivative such as nitromethane.These compositions are well suited for degreasing metals and in the drycleaning of textiles.

Abstract: The tubular preform is injection moulded in an injection mould whose initially axially reduced injection cavity is progressively enlarged in the direction of the axis of the preform in step with its filling by the injected thermoplastic until a moulding cavity is obtained which corresponds to the volume and to the shape of the preform to be produced. To this end, the injection mould comprises external die-halves and a central core, which can be moved in relation to each other in the direction of their common lengthwise axis during the injection moulding cycle.

Abstract: Process for manufacturing oxymethylene copolymers stabilized against thermal degradation, comprising the heating of the copolymer in a medium containing water and a disubstituted cellulose ether.

Abstract: Pharmaceutical compositions containing a salt derived from 3-hydroxybutanoic acid, such as a sodium salt or alternatively a salt derived from an organic nitrogen base such as an amine; the amine can be an amino-acid of natural origin, such as arginine. The compositions according to the invention can be used for the prophylactic and curative treatment of cardiomyopathy of non-ischaemic and ischaemic origin.

Abstract: Device for drying moist air, comprising, in an enclosure (1) provided with openings (5, 6) for the admission and removal of air, a receptacle (10) for a solid desiccant and, under the latter, a layered structure (19) of superposed mats of a filter medium.

Abstract: The seeds are coated by means of a polyester the melting temperature of which is low.The process consists in treating the seeds by means of a solution of the polyester in an organic solvent or by means of the polyester in the liquid or molten state.

Abstract: The process enables peptides to be synthesized from amino acids with the participation of trialkylcyanosilanes.The peptides obtained by this synthesis route are used, in particular, in pharmaceutical applications.

Abstract: Polyetherpolyols corresponding to the general formula: ##STR1## in which: Y denotes oxyalkylene radicals derived from alkene oxides,m denotes a number such that 1.ltoreq.m.ltoreq.2 and n.sub.1 and n.sub.2 denote numbers such that 2.ltoreq.(n.sub.1 +n.sub.2).ltoreq.5.The brominated polyetherpolyols are prepared by the condensation of (m+1) moles of 2-butyne-1,4-diol with m moles of epichlorohydrin in the presence of m moles of a strong base, followed by the addition of (n.sub.1 +n.sub.2) moles of alkene oxide and, finally, by a partial bromination.These brominated polyetherpolyols may be employed, by themselves, or mixed with conventional unhalogenated polyetherpolyols, in the manufacture of rigid polyurethane foams.

Abstract: A process for extracting poly-beta-hydroxybutyrates from an aqueous suspension of microorganisms, in which an azeotropic distillation, and an extraction of the polymer by means of the solvent used, are carried out simultaneously.The poly-beta-hydroxybutyrates obtained can be used in medicine.

Abstract: Coating device whose coating vessel is driven simultaneously with a rotary motion on itself around an axis of rotation and with a planetary motion around this axis of rotation. The device makes it possible to coat various products, especially kernels, seed, fruit, confectionery products, dragees, sweets, pharmaceutical products, and the like.

Abstract: Phosphobrominated polyetherpolyols which contain in their molecule oxyalkylene radicals bound to phosphorus atoms in the phosphate or phosphonate state and 1,4-dioxy-2,3-dibromo-2-butylene radicals in which the ratio of the total number of oxyalkylene radicals to the total number of phosphorus atoms is equal to at least 7.These polyetherpolyols can be used as flame-retarding reactive additives in the manufacture of flame-retardant flexible polyurethane foams involving polyetherpolyols, the foams possessing good comfort-conferring properties.

Abstract: The thermoplastic structures incorporate an inner vinylidene chloride copolymer layer, each face of which is bonded to a vinyl chloride polymer (2) layer through the intermediacy of a separate intermediary vinyl chloride polymer (1) layer whose gel temperatrue and dynamic viscosity are lower than those of the adjacent vinyl chloride polymer (2).The thermoplastic structures with multiple coextruded polymeric layers may be in the form of sheets, plaques, tubes or rigid or semirigid hollow bodies, which can be employed in the field of packaging.

Abstract: An adjustable feed block for a coextrusion die is provided. The feed block comprises a main central channel for conveying a main stream of molten thermoplastic material towards a coextrusion die, and at least one secondary channel, substantially parallel to the central channel, for conveying a second molten thermoplastic intended to form a local coating layer on the main stream. The downstream end of each secondary channel is inclined relative to the central channel and connected to a portion of the periphery of the said channel. The connection between the central channel and each secondary channel is laterally delimited by the ends of two adjustable slides which can be moved at right angles to the axis of the central channel. These slides make it possible to adjust, during operation, the position and width of the streams of thermoplastic deposited on the main stream.

Abstract: Copolymers containing oxymethylene and 2-fluoromethoxyethylene repeat units. These copolymers, of improved heat stability, may be prepared by copolymerizing trioxane with a derivative of a cyclic ether whose molecule contains at least two adjacent carbon atoms and in which an oxymethylene group carries a fluoromethyl substituent, especially epifluorohydrin.