摘要:
The present invention pertains to a fluoropolymer [polymer (F)] comprising: recurring units derived from vinylidene fluoride (VDF), and from 0.01% to 5% by moles of recurring units derived from at least one (meth)acrylic monomer [monomer (MA)] having formula (I) here below: wherein: R1, R2 and R3, equal to or different from each other, are independently selected from a hydrogen atom and a C1-C3 hydrocarbon group, and ROH represents a hydrogen atom or a C1-C5 hydrocarbon moiety comprising at least one hydroxyl group, said polymer (F) comprising end groups having formula —CF2H and/or —CF2CH3 in an amount of at least 30 mmoles per Kg of vinylidene fluoride (VDF) recurring units. The invention also pertains to a process for the manufacture of said polymer (F) and to use of said polymer (F) as binders for the manufacture of electrodes or for the manufacture of membranes.
摘要:
Use in LAN cable applications, as materials for the coating of the primary cable and for the external jacket, of TFE thermoprocessable perfluoropolymers comprising perfluoroalkylvinylethers in the following amounts, expressed as percent by weight on the total of the monomers: a) 0-5.5% of perfluoromethylvinylether (PMVE); b) 0.4-4.5% of perfluoroethylvinylether (PEVE) and/or perfluoropropylvinylether (PPVE); when a) is present, then a)+b) ranges from 1.5% to 5.5% by weight on the total of the monomers; optionally c) 0-6% of hexafluoropropene (HFP); the TFE amount being the complement to 100% by weight.
摘要:
Compositions containing fluorinated thermoplastic elastomers with different moelcular weight and with different plastomeric phase/elastomeric phase ratio, essentially formed by: (a) 30-80% by weight, preferably 50-80%, of a fluorinated thermoplastic elastomer, having a block structure of A-B-A type, wherein A is a plastomeric segment and B is an elastomeric segment; (b) 10-50% by weight, preferably 20-40% of a fluorinated thermoplastic elastomer having a block structure of A-B-A type; (c) 0-30% by weight, preferably 0-15%, of a fluorinated plastomer preferably of the same kind as that contained in the component (a) and/or (b).
摘要:
New fluoroelastomers are described, comprising monomeric units deriving from a bis-olefin having general formula: ##STR1## wherein: R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, equal or different from each other, are H or alkyls C.sub.1 -C.sub.5 ; Z is an alkylene or cycloalkylene radical C.sub.1 -C.sub.18, linear or branched, optionally containing oxygen atoms, preferably at least partially fluorinated, or a (per)fluoropolyoxyalkylene radical.Such products are endowed with improved processability, especially during calendering of the vulcanization mixture, along with superior mechanical and workability properties during extrusion and injection molding, with a very good mold release.
摘要:
A polyvinylidenefluoride (PVDF) having high mechanical properties both at room temperature and at high temperatures, having very good processability and high thermochemical resistance to dehydrofluorination, is prepared by means of a polymerization process of vinylidenefluoride in aqueous emulsion at a temperature comprised between 95.degree. and 120.degree. C., in the presence of a chain transfer agent. In this way it is possible to obtain, using non-hazardous peroxidic initiators (for instance diterbutylperoxide), a PVDF particularly suitable for applications where high mechanical and thermochemical resistance properties are required, such as for instance the manufacture of articles for chemical industry (pipes, valves, fittings, tanks, heat exchangers, membranes, flanges, etc.).
摘要:
Fluoroelastomeric copolymers exhibiting high resistance to bases and alcohols, as well as high mechanical properties and low-temperature resistance, comprising, in moles:4-75% of units of vinylidene fluoride;12-40% of units of hexafluoropropene and/or perfluorovinylether and/or hydropentafluoropropene and/or chlorotrifluoroethylene;2-35% of units of an olefin containing up to 4 carbon atoms;2-60% of units of tetrafluoroethylene, provided that, when the sum of the olefin units and the perfluorovinylether units is equal to or greater than 70%, such copolymers possess a molecular weight sufficiently high to exhibit good mechanical characteristics.
摘要:
Use of perfluoropolyethers having perfluoroalkyl end groups with a molecular weight ranging from 500 to 1500, in amounts from 0.5 to 3 parts by weight per 100 parts by weight of elastomer and, optimally, in combination wit polytetrafluoroethylene having a molecular weight lower than about 200,000, as additives to the polymerization latex of rubbers vulcanizable by means of peroxides in order to improve the detachability of the vulcanizate from forming molds.
摘要:
The present invention pertains to an aqueous composition comprising: (A) an aqueous latex comprising at least one vinylidene fluoride (VDF) polymer [polymer (F)] comprising recurring units derived from vinylidene fluoride (VDF) and at least one (meth)acrylic monomer (MA) having formula (I) here below: wherein: —R1, R2 and R3, equal to or different from each other, are independently selected from a hydrogen atom and a C1-C3 hydrocarbon group, and —ROH is a hydrogen atom or a C1-C5 hydrocarbon moiety comprising at least one hydroxyl group, (B) at least one powdery electrode material, and (C) optionally, less than 10% by weight, based on the total weight of the aqueous composition, of at least one organic solvent (S), wherein the polymer (F) in the aqueous latex is under the form of primary particles having an average primary particle size of less than 1 μm, as measured according to ISO 13321. The present invention also pertains to a process for manufacturing an electrode using said aqueous composition, to an electrode comprising a metal substrate coated on at least one surface with said aqueous composition and to use of said electrode for manufacturing a non-aqueous-type electrochemical device.
摘要:
The present invention pertains to a process for the manufacture of a grafted fluorinated polymer comprising at least one grafted side chain comprising one or more glycosidic recurring units [polymer (F)], said process comprising polymerizing: vinylidene fluoride (VDF), optionally, one or more other fluorinated monomers [monomers (F)], and optionally, one or more (meth)acrylic monomers [monomers (MA)], in the presence of at least one polysaccharide derivative [derivative (P)], said polysaccharide derivative having a dynamic viscosity of less than 15 mPa×s, as measured according to ASTM D445 at 20° C. in an aqueous solution at a concentration of 2% by weight, and by further providing novel polymers (F) as defined above.
摘要:
A process for manufacturing a dispersion of a vinylidene fluoride (VDF) thermoplastic polymer [polymer (F)], said process comprising polymerizing VDF in an aqueous phase comprising from 0.5 to 1.5 g/l of at least one surfactant of formula F—(CF2CF2)3—CH2CH2—SO3Xa, wherein Xa is H, a alkali metal or a NRH4 group, with RH being H or a C1-C6 hydrocarbon group [surfactant (T)] and an organic oxidizing agent [agent (O)] as polymerization initiator.