摘要:
Core-shell particles having a core of at least one tetrafluoroethylene (TFE) polymer and having an average primary particle size of less than 50 nm; and a shell of at least one acrylic polymer having recurring units, more than 50% by moles of which being derived from at least one ethylenically unsaturated monomer having directly bonded to one of the sp2 carbon atoms of the ethylenic unsaturation at least one group of formula: Process for manufacturing core-shell particles. Use as ingredients/additives in polymer compositions, polymer composition and articles containing the same.
摘要:
The invention relates to core-shell particles, said particles comprising: a core consisting essentially of at least one tetrafluoroethylene (TFE) polymer [polymer (F)], said core having an average primary particle size of less than 100 nm a shell consisting essentially of at least one high performance polymer [polymer (HPP)], wherein the polymer (HPP) is chosen among polycondensation polymers that have a heat deflection temperature (HDT) of above 80° C. under a load of 1.82 MPa when measured according to ASTM D648. The core-shell particles of the invention advantageously allow obtaining molded articles with homogeneous properties, both when used alone and when used as additive, as they generally do not undergo segregation phenomena.Still objects of the inventions are the process for manufacturing said core-shell particles, the use of said particles as additives, the composition and the articles thereof.
摘要:
A process to substantially remove the fluorinated anionic surfactants from fluoropolymer dispersions comprising the following steps: a) addition to the fluoropolymer dispersion of an anionic polyelectrolyte; b) contact of the dispersion with an anionic exchanger; c) separation of the dispersion from the anionic exchanger and recovery of the dispersion substantially fluorinated anionic surfactant free.
摘要:
The invention relates to an aromatic sulfone polymer composition comprising at least one aromatic sulfone polymer [polymer (P)]; from 0.02 to less than 10 wt %, based on the total weight of the composition, of a tetrafluoroethylene (TFE) polymer [polymer (F)] under the form of nanoparticles, wherein said nanoparticles have an average primary particle size of less than 100 nm. The compositions of the invention advantageously display an unexpected combination of excellent mechanical properties, excellent chemical resistance, excellent optical properties (transparency and/or colorability) and low flammability.Still an object of the invention is a process for manufacturing aromatic sulfone polymer compositions. According to a preferred embodiment, said process comprises a co-coagulating step of an aromatic sulfone polymer solution with TFE nanoparticles. Still objects of the invention are the articles comprising the composition as above specified.
摘要:
The invention pertain to a process for purifying a fluoropolymer dispersion, said process comprising: (i) providing an aqueous dispersion (D) of at least one fluoropolymer [polymer (F)]comprising at least one fluorinated surfactant [surfactant (FS)], having a solids content (SC) of 15% by weight or more; (ii) adding to said aqueous dispersion (D) at least one non-ionic non-fluorinated surfactant [surfactant (NS)]; (iii) adjusting said solid content (SC) to less than 10% by weight, to obtain a diluted aqueous dispersion (dD); (iv) contacting said diluted aqueous dispersion (dD) with at least one adsorbing material, so as to obtain an aqueous dispersion of polymer (F) having a content of the fluorinated surfactant (FS) of less than 1 ppm based on the total weight of solids. Still an object of the invention is an aqueous fluoropolymer dispersion comprising less than 1 ppm of fluorinated surfactant.
摘要:
The invention pertain to a process for purifying a fluoropolymer dispersion, said process comprising: (i) providing an aqueous dispersion (D) of at least one fluoropolymer [polymer (F)] comprising at least one fluorinated surfactant [surfactant (FS)], having a solids content (SC) of 15% by weight or more; (ii) adding to said aqueous dispersion (D) at least one non-ionic non-fluorinated surfactant [surfactant (NS)]; (iii) adjusting said solid content (SC) to less than 10% by weight, to obtain a diluted aqueous dispersion (dD); (iv) contacting said diluted aqueous dispersion (dD) with at least one adsorbing material, so as to obtain an aqueous dispersion of polymer (F) having a content of the fluorinated surfactant (FS) of less than 1 ppm based on the total weight of solids. Still an object of the invention is an aqueous fluoropolymer dispersion comprising less than 1 ppm of fluorinated surfactant.
摘要:
A process to substantially remove the fluorinated anionic surfactants from fluoropolymer dispersions comprising the following steps: a) addition to the fluoropolymer dispersion of an anionic polyelectrolyte; b) contact of the dispersion with an anionic exchanger; c) separation of the dispersion from the anionic exchanger and recovery of the dispersion substantially fluorinated anionic surfactant free.
摘要:
The invention pertains to a process for manufacturing a (per)fluoropolymer, said process comprising polymerizing one or more fluorinated monomers in the presence of a multi-phase medium, said medium comprising: (A) a water phase [phase (W)]; (B) at least one fluorinated surfactant [surfactant (FS)] having formula (I) here below: Rf—(OCF2CF2)k-1—O—CF2—COOXa (I) wherein Rf is a C1-C3 perfluoroalkyl group comprising, optionally, one or more ether oxygen atoms, k is 2 or 3 and Xa is a selected from a monovalent metal and an ammonium group of formula NRN4, wherein RN, equal or different at each occurrence, is a hydrogen atom or a C1-C3 alkyl group; (C) an oil phase [phase (O)] comprising: at least one non-functional (per)fluoropolyether (non-functional PFPE) comprising at least one (per)fluoropolyoxyalkylene chain [chain (RF)] and at least one functional (per)fluoropolyether (functional PFPE) comprising at least one (per)fluoropolyoxyalkylene chain [chain (R′F)] and having a number average molecular weight of at least 1000 and a solubility of less than 1% by weight in water at 25° C.
摘要:
The invention pertains to a method for making a fluoropolymer comprising an aqueous emulsion polymerization of one or more fluorinated monomers wherein said aqueous emulsion polymerization is carried out in the presence of at least one cyclic fluorocompound of the following formula (I): wherein X1, X2, X3, equal or different from each other are independently selected among H, F, and C1-6 (per)fluoroalkyl groups, optionally comprising one or more catenary or non-catenary oxygen atoms; L represents a bond or a divalent group; RF is a divalent fluorinated C1-3 bridging group; Y is a hydrophilic function selected among anionic functionalities, cationic functionalities and non-ionic functionalities.
摘要:
The invention pertains to a polymerization process including polymerizing at least one fluorinated monomer in the presence of a radical initiator and a surfactant in a polymerization medium containing carbon dioxide to provide a polymer product, characterized in that the surfactant is a functional (per)fluoropolyether, which is a polymer comprising recurring units (R1) and at least one functional group having a heteroatom other than fluorine, said recurring units having at least one ether linkage in the main chain and at least one fluorine atom (fluoropolyoxyalkene chain).