Fluorinated elastomers with low glass transition temperatures based on vinylidene fluoride and free of tetrafluoroethylene or siloxane group
OwnerBruno Michel Ameduri, Michel Armand +2inventors
InventorsBruno Michel Ameduri, Michel Armand, Mario Boucher, Bernard Leon Boutevin
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Abstract
The present invention describes synthesis of new fluorinated elastomers presenting very low glass transition temperatures, a good resistance to bases, petroleum and fuels and good properties for forming. These elastomers contain, by way of example, from 90 to 50 mole % of vinylidene fluoride (VDF) and from 10 to 50 molar % of perfluoromethyl vinyl ether (PMVE). In this precise case, they are prepared by radical copolymerisation of VDF and with PMVE in presence of various organic initiators such as for example the peroxides, the peresters or the diazo compounds.
Claims31
Process for fluorinated elastomers preparation by copolymerisation of vinylidene fluoride with at least one perfluorinated vinyl ether and optionally with at least one fluorinated alkene, characterized in that the preparation is conducted by a radical copolymerisation with an organic initiator at a temperature between 20 and 200° C., for a period of time between 3 and 15 hours, at an initial pressure between 2 and 100 bars, and an initial pressure that is allowed to drop progressively as the monomers are consumed.
Fluorinated elastomers comprising a vinylidene fluoride copolymer of vinylidene, at least one perfluorinated vinyl ether and optionally a fluorinated alkene, characterised in that it comprises neither tetrafluoroethylene, nor siloxane groups and presents low glass transition temperatures (Tg) between −35 and −42° C.
Dependencies are inferred from the claim text.