Abstract: The present invention relates to a process for grafting an unsaturated monomer onto a fluoropolymer, having the steps of: a) melt blending the fluoropolymer with the unsaturated monomer; b) forming the blend obtained in a) into films, sheets, granules or powder; c) exposing the products from step b), in the absence of air, to photon (y) or electron (?) irradiation with a dose of between 1 and 15 Mrad; and d) optionally treating the product obtained at c) in order to remove all or part of the unsaturated monomer that has not been grafted onto the fluoropolymer. Structures made with these materials are barriers to many fluids and in particular to petrol and to air-conditioning fluids and may be formed into bottles, tanks, containers, pipes, hoses and vessels of all sorts. They may also be converted into films with which packaging is made.

Abstract: The present invention relates to a composition coextrudable with PVDF and comprising: 30 to 50 parts of PVDF; 70 to 50 parts of a copolymer comprising, by weight, 90 to 50% of methyl methacrylate (MMA) per 10 to 50% of an alkyl (meth)acrylate respectively, the alkyl having from 2 to 24 carbon atoms; 1 to 4 parts of a UV absorber; the total making 100 parts. The invention also relates to coextruded films consisting of this composition as the adhesive layer and a PVDF-based layer of 50 to 100 parts of PVDF per 50 to 0 parts of PMMA respectively. These films possess mechanical properties sufficient to allow them to be used as a coating transparent to visible light but opaque to UV radiation.

Abstract: The present invention relates to a hose having a layer consisting of a fluoropolymer onto which an unsaturated monomer has been irradiation-grafted and, a polyolefin outer layer. The hose is useful for transporting petrol in a service station. In one embodiment a fluoropolymer, preferably PDVF, layer is placed beside the irradiation-grafted fluoropolymer. The hose may consist of a irradiation-grafted fluoropolymer inner layer and a polyolefin outer layer, or multilayer hose with either a central irradiation-grafted fluoropolymer layer and polyolefin inner and outer layers, or a polyolefin central layer and irradiation-grafted fluoropolymer inner and outer layers. The irradiation-grafted fluoropolymer layer may be replaced with a layer of a blend of a fluoropolymer, preferably PVDF, and of an irradiation-grafted fluoropolymer. It may also be covered with a fluoropolymer.

Abstract: The present invention relates to the use for storing or transporting chemicals of a structure comprising an inner layer in contact with the fluid to be stored or transported, consisting of a fluoropolymer onto which an unsaturated monomer has been grafted by irradiation and, directly attached to the latter, a polyolefin outer layer. According to a variant, the structure comprises a fluoropolymer, preferably PDVF, layer placed beside the radiation-grafted fluoropolymer. The invention also relates to a structure having a central layer consisting of a radiation-grafted fluoropolymer and, directly attached to the latter, a polyolefin outer layer and a polyolefin inner layer. The polyolefin inner layer is the layer in contact with the chemicals. According to a variant, the radiation-grafted fluoropolymer layer is replaced with a layer of a blend of a fluoropolymer, preferably PVDF, and of a radiation-grafted fluoropolymer.

Abstract: The present invention relates to a thermoformable multilayer film comprising in succession: an optional protective layer (A); a layer (B) comprising (the total being 100% by weight) 0 to 30% of a fluoropolymer (B1) and 100 to 70% of a functionalized polymer (B2) essentially consisting of alkyl (meth)acrylate units; a layer (C) based on an ethylene/alkyl (meth)acrylate/unsaturated epoxide copolymer; a polyolefin tie layer (D); the layers adhering to one another in their respective contact regions. This film is obtained by coextrusion or coating of the various layers, the layer (A) possibly being laminated using the standard technique for thermoplastics. This film is then used to cover various substrates, for example by injecting the substrate in the melt onto the multilayer film deposited in the bottom of an injection mould, the layer (B) or the optional layer (A) of the film being placed against the wall of the mould. The present invention also relates to the substrates coated with these films.

Abstract: The present invention relates to a structure comprising, in succession: a metal layer L1, optionally a fluorinated primer L2, which is a blend comprising, by weight, 1 to 100% of at least one modified fluoropolymer per 0 to 99% of fluoropolymer, respectively, and a layer of a fluoropolymer L3; such that, if the primer layer L2 is absent, the fluoropolymer L3 is a blend comprising, by weight, 1 to 100% of at least one modified fluoropolymer per 0 to 99% of fluoropolymer, respectively; the said modified fluoropolymer being chosen from: fluoropolymers grafted with an unsaturated monomer, the grafting being carried out in the absence of oxygen by irradiation of the unsaturated monomer and of the fluoropolymer that are melt-blended beforehand, and fluoropolymers irradiated in the presence of oxygen (also referred to as oxidized fluoropolymers). The structure is useful as a positive electrode for a lithium-ion battery.

Abstract: The present invention relates to a composition comprising, by weight, the total being 100%: A) 40 to 80% of PVDF; B) 10 to 40% of PMMA; and C) 10 to 40% of a conductive filler. This composition has a PTC effect and is advantageously used in the form of a film (paint) covering a substrate. The composition of the invention is dissolved in a solvent and then spread over a substrate and the solvent evaporated. The metal terminals for connection to the electrical circuit may be placed at the ends of the coating before or after application. The invention also relates to a composite, namely the substrate covered with the PTC composition described above.

Abstract: The present invention relates to a process for oxidizing a fluoropolymer, comprising the steps of: a) forming a fluoropolymer is into a film, a sheet, granules or powder; b) exposing the products from step a), in the presence of oxygen, to photon (?) or electron (?) irradiation with a dose of between 1 and 15 Mrad; and c) optionally treating the product obtained in b) in order to remove all or some of the by-product impurities. The oxidized fluoropolymer thus obtained may be used as such or in a blend with at least one polymer. Structures comprising at least one layer of this oxidized fluoropolymer and at least one layer of another material may be formed into bottles, tanks, containers, pipes, hoses and vessels of all sorts. They may also be converted into films with which packaging is made. The invention also relates to the oxidized fluoropolymer.

Abstract: The present invention relates to a multilayer structure comprising the following successive layers: a polyamide or HDPE (high-density polyethylene) layer; a tie layer; an impact-modified EVOH layer; optionally, a tie layer; and a polyamide or polyamide/polyolefin blend or polyolefin layer, the latter layer possibly containing fillers in order to make it antistatic; and such that the impact-modified EVOH layer is a blend based on EVOH and at least one modifier chosen from: a) functionalized ethylene/alkyl (meth)acrylate copolymers; b) products resulting from the reaction of (i) a copolymer of ethylene and of an unsaturated monomer X grafted or copolymerized with (ii) a polyamide; c) blends of a) and b); d) polyamides, preferably PA-6; e) blends of a) and d); f) elastomers, preferably EPR, EPDM and NBR, these elastomers possibly being functionalized; g) S-B-M triblocks; h) triblocks formed from a poly(butyl acrylate) block between two PMMA blocks; and i) linear or star S-B-S block copolymers, these optionally b

Abstract: The present invention relates to a multilayer tube comprising, in its radial direction from the outside inwards: an outer layer formed from a polyamide, a layer formed from a copolyamide, a layer formed from an EVOH, a layer formed from a copolyamide, an inner layer formed from a polyamide, the layers being successive and adhering to one another in their respective contact region. Advantageously, the inner layer is formed by a compound based on a polyamide and electrically conducting carbon black, producing a surface resistivity of less than 106 ?/?. The outside diameter of these tubes may range from 6 to 110 mm and the wall thickness may be from 0.5 to 5 mm. Advantageously, the petrol tube according to the invention has an outside diameter ranging from 6 to 12 mm and a total wall thickness of 0.36 mm to 1.

Abstract: The present invention relates to a PTC composition comprising, by weight, the total being 100%: A) 40 to 80% of PVDF; B) 0 to 40% (advantageously 10 to 40%) of an acrylic or styrene polymer; C) 0 to 40% of an epoxy resin; D) 0 to 60% of at least one metal oxide; E) 0 to 25% of a carbonaceous conductive filler D+E being equal to at least 10%. To prepare the composition of the invention, the various constituents are blended in such a way that (A) is in the melt state, then the product obtained is extruded, moulded or injection-moulded or else deposited on a substrate. Once the composition has been converted into an article, for example into a sheet or bar, it is provided with at least two electrodes that serve as the power lead-in and return, respectively. The composition may also be placed between two conducting plates that serve as the power lead-in and return, respectively.

Abstract: The present invention concerns a microcomposite powder comprising: flat graphite particles GLP having sides from 50 to 1000 &mgr;m and a thickness from 5 to 50 &mgr;m, consisting of agglomerates of more elementary graphite particles joined together and superimposed so that their principal planes are mutually parallel, said particles being covered with particles of a fluoropolymer from 0.1 to 0.5 &mgr;m in size.

Abstract: The present invention relates to a microcomposite powder comprising particles from 1 um to 300 um of an electrically conductive product, which are coated with particles from 0.1 &mgr;m to 0.5 &mgr;m of a fluoropolymer. According to one advantageous form of the invention the microcomposite powder comprises a product (A) which is a polymer or an oligomer which can be dissolved with a solvent which is not a solvent for the fluoropolymer or for the electrically conductive product. The present invention also relates to objects consisting of this powder. These objects may be bipolar plates for fuel cells, or supercapacitor components.

Abstract: A composition coextrudable with PVDF comprises in parts by weight: 20 to 40 parts of PVDF; 40 to 60 parts of PMMA; 5 to 18 parts of an acrylic elastomer; 1 to 4 parts of a UV absorber; the total making 100 parts. Coextruded films comprise a layer of the above coextrudable composition directly attached to the latter; and a PVDF-based layer comprising, as main constituents, 50 to 100 parts of PVDF per 50 to 0 parts of PMMA respectively. The PVDF layer may be in the form of two layers: one placed against the coextrudable layer and comprising, as main constituents, 50 to 90 parts of PVDF per 50 to 10 parts of PMMA respectively; and the other (also called the outer layer) comprising, as main constituents, 75 to 100 parts of PVDF per 25 to 0 parts of PMMA respectively. The resultant products are generally applied to substrates, e.g. as protective films.

Abstract: The present invention relates to the use of films, formed from an adhesive layer and a layer (A), for coating articles made of a thermoset, the adhesive layer comprising, by weight: 0 to 60 parts of PVDF, 10 to 100 parts of functionalized PMMA, 0 to 50 parts of an acrylic elastomer and 0 to 4 parts of a UV absorber, the total making up 100 parts, the layer (A) comprising, as main constituents, 0 to 100 parts of PVDF per 100 to 0 parts of PMMA, respectively.

Abstract: The present invention relates to a conductive composition comprising (i) a fluoropolymer, (ii) an electrically conductive product and (iii) a triblock copolymer ABC, the three blocks A, B and C being linked together in this order, each block being either a homopolymer or a copolymer obtained from two or more monomers, block A being linked to block B and block B to block C by means of a covalent bond or an intermediate molecule linked to one of these blocks via a covalent bond and to the other block via another covalent bond, and such that: block A is compatible with the fluoropolymer, block B is incompatible with the fluoropolymer and is incompatible with block A, block C is incompatible with the fluoropolymer, block A and block B. The invention also relates to the components manufactured with the above composition. These components may be plates, films, tubes, rods, centrifugal pump components and containers.

Abstract: A composition coextrudable with PVDF comprises in parts by weight: 20 to 40 parts of PVDF; 40 to 60 parts of PMMA; 5 to 18 parts of an acrylic elastomer; 1 to 4 parts of a UV absorber; the total making 100 parts. Coextruded films comprise a layer of the above coextrudable composition directly attached to the latter; and a PVDF-based layer comprising, as main constituents, 50 to 100 parts of PVDF per 50 to 0 parts of PMMA respectively. The PVDF layer may be in the form of two layers: one placed against the coextrudable layer and comprising, as main constituents, 50 to 90 parts of PVDF per 50 to 10 parts of PMMA respectively; and the other (also called the outer layer) comprising, as main constituents, 75 to 100 parts of PVDF per 25 to 0 parts of PMMA respectively. The resultant products are generally applied to substrates, e.g. as protective films.

Abstract: The present invention relates to a thermoformable multilayer film comprising in succession: a protective layer (A); a transparent layer (B) comprising (by weight the total amount being 100%) 0 to 100% of a fluoropolymer (B1) and 100 to 0% of a polymer (B2) essentially consisting of alkyl (meth)acrylate units; a layer (C) based on a polyamide with amine terminal groups; a layer (D) consisting of a polyolefin functionalized by an unsaturated carboxylic acid anhydride; a bonding layer (E) made of a polyolefin, said film being obtained by coextruding the various layers, said film being used to cover various substrates, for example by injection-moulding the substrate in the melt onto the multilayer film placed in the bottom of an injection mould, the layer (A) of the film being placed against the wall of the mould.

Abstract: The invention describes the use of compositions containing at least one thermoplastic polymer and an epoxy resin modified by at least one aromatic polyamine to coat surfaces, especially pipes through which oil is transported. The polymer compositions used contain at least one thermoplastic polymer which is preferably amorphous selected from the group formed by polysulphones, polyetherimides and polyphenylene esters and at least one epoxy resin modified by at least one aromatic polyamine containing at least two primary amine groups in its molecule. Different layers of polymers are deposited on different types of surface, more particularly as internal and external coatings for conduits. The invention also provides a surface coating comprising such compositions. Multi-layer coatings are also produced.

Abstract: The present invention relates to a conductive composition comprising (i) a fluoropolymer, (ii) an electrically conductive product and (iii) a triblock copolymer ABC, the three blocks A, B and C being linked together in this order, each block being either a homopolymer or a copolymer obtained from two or more monomers, block A being linked to block B and block B to block C by means of a covalent bond or an intermediate molecule linked to one of these blocks via a covalent bond and to the other block via another covalent bond, and such that: