Abstract: Process for drying wet F32, which comprises placing a stream of the said F32 in continuous contact with a feed stock of a composition comprising a molecular sieve chosen from a 3A type sieve, at a temperature of between 5 and 78° C. and at a pressure of between 0.5 and 25 atm.
Abstract: The invention relates to a process for the polymerization of at least one monomer which can be polymerized via a radical route, in the presence of a stable free radical and of a polymerization initiator, such that, per 100 mol of monomer, the molar amounts of stable radical (SFR) and of initiator (INIT) are such that [(SFR)×FSFR]/[(INIT)×FINIT]<0.15 and FSFR×(SFR)<0.2 mol, in which FSFR represents the functionality of the stable free radical and FINIT represents the functionality of the initiator. The process according to the invention has advantageous kinetics, allows the production of grafted or block copolymers and can be carried out in an extruder.
Abstract: A thermoplastic material composite panel, comprising a transparent thermoplastic base layer, light conducting, having a thickness generally in the range 3-40 mm, and a light diffusing layer, having a thickness generally in the range 10-1500 micron, placed on one face of the base layer, said diffusing layer being characterized in that it contains barium sulphate in amount by weight, expressed as per cent ratio on the total weight of the diffusing layer, in the range 0.01-2%, the barium sulphate having average particle sizes in the range 0.1-50 micron, the composite sizes being-greater than or equal to 10 cm.
Abstract: A drying composition according to the invention is composed of a solution of a surface-active agent in a mixture of a fluorinated hydrocarbon and of a polyfluorinated alcohol of formula: Rf—(CH2)n—OH??(I) in which n is equal to 1 or 2 and Rf represents a linear perfluoroalkyl radical containing from 2 to 8 carbon atoms.
Abstract: Composite plastic compositions based on the dispersion of selected cross-linked polymers in certain thermoplastic matrices are disclosed. The composite compositions are readily formed and processed by thermal extrusion processes versus conventional casting processes. Preferred composite plastics compositions based on cross-linked poly(alkyl (meth)acrylate) polymers and modified poly(alkyl (meth)acrylate) thermoplastics are especially useful in the preparation of synthetic architectural materials having a mineral-like appearance, such as that of granite.
Abstract: Activator solid support for metallocenes as catalysts in the polymerization of olefins, characterized in that it consists of a group of support particles for a solid catalytic component, which are formed from at least one porous mineral oxide, the said particles having been modified in order to carry, on the surface, aluminum and/or magnesium Lewis-acid sites of formula:
groups coming from a functionalization agent having reacted with —OH radicals carried by the base particles of the support, the functionalization reaction having been followed by a fluorination reaction. The catalytic system according to the invention comprises (a) a metallocene catalyst, which has, if required, been subjected to a prealkylation treatment; (b) a cocatalyst; and (c) an activator solid support for metallocene, as defined above, it being possible for the cocatalyst (b) to be absent if the metallocene catalyst (a) has been prealkylated.
Type:
Grant
Filed:
April 1, 2003
Date of Patent:
August 24, 2004
Assignee:
Elf Atochem S.A.
Inventors:
Thierry Saudemont, Roger Spitz, Jean-Pierre Broyer, Jean Malinge, Nathalie Verdel
Abstract: A composition based on dimethyl disulphide (DMDS) with a masked smell according to the invention comprises, by weight, at least 95% of DMDS, less than 500 ppm of methyl mercaptan, less than 100 ppm of dimethyl sulphide and up to 1% of at least one odor-masking agent.
Abstract: A latex which forms a film by evaporation at a temperature of less than 40° C. is based on hydrophobic polymer particles having a core/shell structure. The particles consist of 70 to 90% by weight of at least one polymer with a soft character having a glass transition temperature of less than 20° C. forming the core, and 10 to 30% by weight of at least one polymer with a hard character having a glass transition temperature of greater than 50° C. forming the shell. When applied to any surface and after drying at low temperature, the latex, without the use of any coalescents or volatile organic compounds, provides a continuous film which is homogeneous, has no surface tack and has good mechanical integrity.
Type:
Grant
Filed:
April 30, 2002
Date of Patent:
April 20, 2004
Assignee:
Elf Atochem S.A.
Inventors:
Xavier Drujon, Pascale Fabre, Ludwik Leibler, Gilles Meunier, Fabrice Domingues Dos Santos
Abstract: Bifunctional primer naphthalene compounds having the formula:
wherein M″ is an alkali metal, preferably sodium or lithium, and R1 and R2 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 continuous process for the preparation of pivaloyl chloride and of aroyl chloride, in particular of benzoyl chloride, which consists in reacting pivalic acid with a trichloromethylated aromatic compound in the presence of a catalyst at a temperature of between 60° C. and 180° C. under reduced pressure. The products formed are continuously removed from the reaction region, the hydrogen chloride formed being treated in a washing region in which a trichloromethylated compound moves countercurrentwise.
Abstract: A method of producing modified polyester moulded articles which is characterized in that, when producing moulded articles from a modified polyester composition comprising a polyester composed of an acid component chiefly consisting of aromatic dicarboxylic acid and glycol component chiefly consisting of aliphatic diol, and a modified polyolefin, there is incorporated an ethylene-acrylate copolymer; together with the moulded articles produced thereby.
Abstract: Multilayered article including a functionalized and vulcanized elastomer adherent by itself to a thermoplastic chosen from polyamides, PBT, mixtures containing polyvinylidene fluoride and ethylene/vinyl alcohol and ethylene/tetrafluoroethylene copolymers.
Composite tubular article made up of an outer sheath of vulcanized elastomer adherent to a hydrocarbon-barrier thermoplastic or associated with an inner layer for producing imperviousness.
Type:
Grant
Filed:
October 19, 1995
Date of Patent:
June 10, 2003
Assignee:
Elf Atochem S.A.
Inventors:
Martine Cerf, Olivier Denizart, Christian Dousson
Abstract: The objective of the present invention lies in providing a resin composition which enables water vapor permeability to be controlled over a broad range while maintaining a high gas permeability, together with molded articles or packaging materials comprising said composition, in particular a packaging material for foodstuffs like fruit and vegetables. A thermoplastic resin composition which is characterized in that a polymer (A) containing polyether chains as structural units, polyethylene (B) of density as specified in JIS K6760 of less than 0.91 g/cm3 and a compatibilizing agent (C) are blended together in proportions by weight of A/B/C=99.5 to 0.5/0.5 to 99.5/0 to 30 (where A+B+C=100); and molded articles comprising said composition, in particular a packaging material for vegetables and fruit cultivation or foodstuffs storage.
Abstract: Process for drying wet F32, which comprises placing a stream of the said F32 in continuous contact with a feed stock of a composition comprising a molecular sieve chosen from a 3A type sieve, at a temperature of between 5 and 78° C. and at a pressure of between 0.5 and 25 atm.
Abstract: The invention concerns a composition comprising an ethylene/alpha-olefin metallocene copolymer of density less than 0.900 g/cm3 and an ethylene/alkyl (meth)acrylate radical copolymer. The invention also concerns films obtained from said composition, in particular a stretchable adhesive film, and a high temperature extrusion method.
Abstract: The invention concerns a composition comprising an ethylene/alpha-olefin metallocene copolymer and an ethylene/alkyl (meth)acrylate radical copolymer, the ratio of their secant moduli being greater than 1. The invention also concerns films obtained from said composition, in particular a stretchable adhesive film, and a high temperature extrusion method.
Abstract: The present invention relates to a process for the preparation of products of formula (1):
in which R denotes H or an alkyl group containing from 1 to 10 carbon atoms, it being possible for this alkyl group to be substituted by one or more aryl, heteroaryl, hydroxyl or alkenyl groups, in which process hydrazine is reacted with a deficiency of carboxylic acid RCOOH and then the water of reaction and optionally the water of dilution of the hydrazine and of the acid is removed.
It is particularly useful for preparing 4-amino-1,2,4-triazole.
Abstract: In order to replace 1,1,2-trichloro-1,2,2-trifluoroethane and 1,1-dichloro-1-fluoroethane in compositions for treating solid surfaces (in particular defluxing), the invention proposes the use of a quasi-azeotropic mixture containing, by weight, from 75 to 95% of 1,1,1,3,3-pentafluorobutane, from 1 to 15% of methylene chloride and from 1 to 10% of methanol.
Abstract: Aqueous alkali metal chloride solutions, typically destined for electrolysis for the production of chlorine and containing a contaminating amount of iodine values in other than the periodate state, are purified by oxidizing the iodine values therein to the periodate oxidation state of +7 and then separating such periodate values therefrom. The starting alkali metal chloride solutions may also contain contaminating amounts of ammonium values, which in turn are oxidized, preferably simultaneously, to molecular nitrogen and degassed therefrom.
Abstract: The present invention relates to the manufacture of a dialkylaminoalkyl (meth)acrylate by transesterification of methyl or ethyl (meth)acrylate with an amino alcohol. The transesterification catalyst is chosen from tetrabutyl, tetraethyl and tetra(2-ethylhexyl) titanates. The reaction is carried out in a stirred reactor at 90-120° C., after which the crude reaction mixture is sent to a tailing column (C1), the flow from the top of this column is sent to a topping column (C2) and the flow from the bottom of this column si then sent to a final rectification column (C3). A dialkylaminoalkyl (meth)acrylate of high purity is obtained in this way.
Type:
Grant
Filed:
April 21, 1999
Date of Patent:
August 20, 2002
Assignee:
Elf Atochem S.A.
Inventors:
Patrice Hurtel, Charles Hazan, Norbert Richard