Abstract: The present invention relates to a method for radiation grafting a compound by irradiation, that can be grafted onto a fluoropolymer, so as to prevent destabilization of the fluorinated polymer. Said method comprises the following steps: a) the fluoropolymer is mixed in the melted state thereof with a graftable compound; b) the mixture obtained in a) is converted into films, plates, granulates or powder; c) the products from step b) are subjected to photonic (?) or electronic (?) irradiation in a dose of between 0.5 and 15 Mrad; and d) optionally, the products from step c) are washed and/or a degassed. According to said method, a stabilizing agent is added to the fluorinated polymer. Said stabilizing agent can be an antioxidant, a graftable metal salt, or a combination of the two. The invention also relates to structures comprising at least one layer of said mixtures and at least one layer of another material, and to the use of said structures to obtain a barrier effect.

Abstract: The invention relates to a multilayer tube comprising (in the order from the inside to the outside of the tube), layers arranged one on top of the other: an optional layer L1 comprising at least one fluorinated polymer, preferably a PVDF; a layer L2 comprising at least one functionalized PVDF, obtained by radiation-grafting of at least one unsaturated polar monomer onto a PVDF; an optionally layer L3 of an adhesion binder; a layer L4 comprising at least one polyolefin optionally mixed with at least one functionalized polyolefin; an optional barrier layer L5; an optional layer L6 comprising at least one polyolefin, optionally in a mixture with at least one functionalized polyolefin; characterized in that the PVDF onto which the unsaturated polar monomer is grafted is a VDF copolymer those weight content is at least 50%, preferably at least 75%, and at least one monomer copolymerizable with the VDF, having the following characteristics: a crystallization temperature Tc (measured by DSC as per the ISO Standard 1

Abstract: The invention relates to a copolymer of VDF and at least one monomer that is copolymerizable with VDF, having a VDF weight content of at least 50%, preferably at least 75%, onto which at least one unsaturated polar monomer is radiation grafted, characterized in that the VDF copolymer has, before grafting, the following characteristics: a crystallization temperature Tc (measured by DSC according to the standard ISO 11357-3) ranging from 50 to 120° C., preferably from 85 to 110° C.; a yield strength ?Y ranging from 10 to 40 MPa, preferably from 10 to 30 MPa; and a melt viscosity ? (measured with a capillary rheometre at 230° C. and 100 s?1) ranging from 100 to 1500 Pa·s, preferably from 400 to 1200 Pa·s. The invention also relates to a blend comprising this modified copolymer and a PVDF. This modified copolymer or the blend may be combined with a thermoplastic polymer, an elastomer or an inorganic material.

Abstract: The present invention relates to a method for the radiation grafting of a compound that can be grafted onto a fluoropolymer, so as to prevent destabilization of the fluoropolymer, comprising the following steps: a) the fluoropolymer is melt-blended with a graftable compound; b) the blend obtained at a) is formed into films, sheets, granules or powder; c) the products from step b) are subjected to photon (?) or electron (?) irradiation with a dose of between 0.5 and 15 Mrad; and d) optionally, the products from step c) are subjected to a washing and/or a degassing operation, and in which a stabilizer is blended into the fluoropolymer. The stabilizer may be an antioxidant, a graftable metal salt or else a combination of the two. The invention also relates to structures comprising at least one layer of these blends and at least one layer of another material. The invention also relates to the use of these structures in order to obtain a barrier effect.

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 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.