Abstract:
A process for reducing the number of unstable end-groups in a fluorinated polymer is disclosed, said process comprising reacting a fluorinated polymer comprising unstable end-groups with fluorine in the presence of at least one (per)haloolefin comprising at least one carbon-carbon double bond and having at least one fluorine or chlorine atom on either one of the carbon atoms of said double bond. The fluorinated polymer may be selected from those polymers comprising recurring units derived from at least one ethylenically unsaturated fluorinated monomer or from fluorinated polyethers.
Abstract:
Process for producing a thermoplastic polymer powder, which comprises the steps of: (i) compression-molding a powdery raw material of a thermoplastic polymer to form tablets, by means of a tablet press; and, (ii) comminuting the tablets to form the thermoplastic polymer powder. Further disclosed is a polymer powder obtained by said process, which typically has an average particle size ranging from 1 to 100 μm, and is further characterized by a combination of attributes which are in favour of powder coating application.
Abstract:
A poly-[1-4]-D-glucosamine derivative comprising [1-4]-D-glucosamine recurring units and comprising a fluoropolyether chain bound to the nitrogen atom in the C-2 position of at least one of the [1-4]-D-glucosamine recurring units.
Abstract:
The invention pertains to a tetrafluoroethylene (TFE) copolymer comprising recurring units derived from at least one perfluoroalkyl(oxy)vinylether of formula CF2═CF—O—Rf, wherein Rf is a C1-C6 perfluoroalkyl radical possibly comprising one or more ethereal oxygen atoms [monomer (F)], in an amount of 0.005 to 0.025% moles, with respect to the total moles of the copolymer, wherein a particular relation between monomer content and amorphous index is satisfied, and to a process for its manufacture by emulsion polymerization in the presence of certain cyclic surfactants.
Abstract:
The present invention provides a fluorinated ionomer [polymer (I)] comprising recurring units derived from at least the following monomers: (i) 5 to 50% by weight of a fluorinated monomer [monomer (A)] containing at least one —SO2X functionality, preferably having the formula of CF2═CF—O—(CF2CF(CF3)O)m—(CF2)mSO2X (I) wherein m is 0 or 1, n is an integer between 0-10, and X is selected from F, OH, and O−Me+, wherein Me+ indicates an alkali metal ion or an ammonium cation of formula NR4− where each R independently represents a hydrogen atom or a monovalent organic radical selected from aliphatic radicals having from 1 to 8 carbon atoms and arylic or alicyclic radicals having from 3 to 8 carbon atoms; (ii) a non-functional fluorinated monomer [monomer (B)] having at least one ethylene unsaturation; and (iii) a fluorinated polyfunctional compound having the general formula: (CR1R2═CFCF2—O)a—Rf—((O)c—CF═CR3R4)b (II) wherein: a is an integer equal to or larger than 1, preferably a is 1, 2, or 3; b is 0 or 1 and the sum of a and b is an integer equal to or larger than 2; c is 0 or 1; R1, R2, R3 and R4 are independently selected from F, H, alkyl, alkoxy, polyoxy alkyl, perfluoroalkyl, perfluoroalkoxy or perfluoropolyoxy alkyl, preferably F; and Rf represents a hydrocarbon or fluorocarbon group having at least two carbon atoms. The low-EW perfluorinated ionomers made of polymer (I) are adapted to be processed into thin films, which are found to have superior physical stability than the existing products and are thus well suited for low humidity or high temperature electrochemical applications. Moreover, these low-EW ionomers are melt processable and have limited loss of volatile substances at their melt processing temperatures.
Abstract:
A process for reducing the amount of soluble polymeric fractions in a sulfonyl fluoride polymer. The process comprises contacting the sulfonyl fluoride polymer with a fluorinated fluid followed by separation of the polymer from the fluid. The fluorinated fluid is selected from hydrofluoroethers and hydrofluoropolyethers. The invention further relates to sulfonyl fluoride polymers obtainable by the process and having a heat of fusion not exceeding 4 J/g and containing less than 15% by weight of polymeric fractions having an average content of monomeric units comprising a sulfonyl functional group exceeding 24 mole %. The sulfonyl fluoride polymers so obtained are particularly suitable for the preparation of ionomeric membranes for use in electrochemical devices.
Abstract:
The present invention pertains to a process for manufacturing a fluoropolymer hybrid organic/inorganic composite, said process comprising: (i) providing a mixture comprising: (a) at least one fluoropolymer comprising recurring units derived from at least one fluorinated monomer and at least one comonomer [comonomer (MA)] comprising at least one hydroxyl group [polymer (F)]; (b) at least one metal compound [compound (M)] of formula (I): X4-mAYm, (I) wherein m is an integer from 1 to 4, and, according to certain embodiments, from 1 to 3, A is a metal selected from the group consisting of Si, Ti and Zr, Y is a hydrolysable group, X is a hydrocarbon group, optionally comprising one or more functional groups; (c) a liquid medium comprising at least one compound selected from the group consisting of a diester of formula (IIde) and an ester-amide of formula (IIea): R1—OOC—Zde—COO—R2 (IIde) R1—OOC—Zea—CO—NR3R4 (IIea) wherein: R1 and R2, equal to or different from each other, are independently selected from the group consisting of C1-C20 hydrocarbon groups, R3 and R4, equal to or different from each other, are independently selected from the group consisting of hydrogen, C1-C36 hydrocarbon groups, possibly substituted, being understood that R3 and R4 might be part of a cyclic moiety including the nitrogen atom to which they are bound, said cyclic moiety being possibly substituted and/or possibly comprising one or more than one additional heteroatom, and mixtures thereof, Zde and Zea, equal to or different from each other, are independently a linear or branched C3-C10 divalent alkylene group; and (d) optionally, at least one electrolytic salt (ES); (ii) reacting at least a fraction of hydroxyl groups of said comonomer (MA) of said polymer (F) with at least a fraction of the hydrolysable groups Y of said compound (M), so as to obtain a grafted fluoropolymer [polymer (Fg)] comprising one or more pendant groups of formula —Ym-1AX4-m; and (iii) hydrolysing and/or polycondensing said compound (M) and/or said pendant groups of formula —Ym-1AX4-m to yield a liquid mixture comprising the fluoropolymer hybrid organic/inorganic composite and incorporating said liquid medium.
Abstract:
The present invention pertains to a cable comprising: —at least one conductor coated by an insulation coating layer, —a first protective layer surrounding said insulation coating layer, said first protective layer at least comprising, but preferably being made of a tetrafluoroethylene (TFE) copolymer comprising from 0.8% to 2.5% by weight of recurring units derived from at least one perfluorinated alkyl vinyl ether having formula (I) here below: CF2═CF—O—Rf, wherein Rf is a linear or branched C3-C5 perfluorinated alkyl group or a linear or branched C3-C12 perfluorinated alkyl group comprising one or more ether oxygen atoms, said TFE copolymer having a melt flow index comprised between 1.0 and 6.0 g/10 min, as measured according to ASTM D1238 at 372° C. under a load of 5 Kg [polymer (F)]; —optionally, a second protective layer surrounding said first protective layer, and —an armor shell surrounding said first or second protective layer. The invention also pertains to use of the cable in downhole wells.
Abstract:
The present invention relates (per)fluoropolyether compounds comprising a (per)fluoropolyether chain (Rf) having at least two chain ends, wherein at least one of said chain ends have a bi- or ter-phenyl group bearing at least one nitro group and, optionally one or more further substituents. The invention also relates to processes for the preparation of such compounds and to their use for the preparation of lubricant compositions in the form of oils or greases.
Abstract:
A process for reducing the number of unstable end-groups in a fluorinated polymer is disclosed, said process comprising reacting a fluorinated polymer comprising unstable end-groups with fluorine in the presence of at least one (per)haloolefin comprising at least one carbon-carbon double bond and having at least one fluorine or chlorine atom on either one of the carbon atoms of said double bond. The fluorinated polymer may be selected from those polymers comprising recurring units derived from at least one ethylenically unsaturated fluorinated monomer or from fluorinated polyethers.