Abstract: The invention relates to the field of chemistry and relates to radically coupled PTFE polymer powders that can be used, for example, as tribomaterials, and a method for the production thereof. There is disclosed radically coupled PTFE polymer powders which, when incorporated into a matrix as PTFE polymer compound, exhibit improved wear resistance, and furthermore a simple and efficient method for the production thereof. There is provided radically coupled PTFE polymer powders comprising radiation-chemically and/or plasma-chemically modified PTFE powders, onto the particle surface of which homopolymers, copolymers or terpolymers are radically coupled via a reaction in dispersion or in solid.

Abstract: An inorganic oxide dispersion containing an organic solvent, and inorganic oxide particles surface-treated with at least one of a hydrolyzate and a partial condensate of an organosilane compound represented by formula (I), the inorganic oxide particles being dispersed in the organic solvent: (R10)m—SI(X)4-m (I) as defined herein, the surface treatment of the inorganic oxide particles being carried out in a presence of at least one of: (a) an acid catalyst; and (b) a metal chelate compound having Zr, Ti or Al as a center metal and at least one of an alcohol represented by formula: R3OH in which R3 represents an alkyl group having 1 to 10 carbon atoms, and a compound represented by formula: R4COCH2COR5 as defined herein, as a ligand.

Abstract: To provide an amorphous fluorinated polymer which is soluble in a fluorinated solvent having a boiling point of at most 70° C., and a fluorinated polymer composition containing it. An amorphous fluorinated polymer characterized by having a fluorine content of at least 50 mass % and an intrinsic viscosity of at least 0.03 g/dL and less than 0.05 dL/g as measured in perfluoro(2-butyltetrahydrofuran) at 30° C.

Abstract: Hydrophobic coating compositions are provided as are processes to coat articles with the compositions. Extremely hydrophobic coatings are provided by the compositions. Durable, weatherable and scratch-resistant coatings are provided by compositions comprising a trifluoromethyl-containing component and a hardenable material. Weatherable coatings are also provided by compositions comprising a mobile non-volatile fluorinated component and a hardenable material. Processes are also provided for forming hydrophobic coatings on articles.

Abstract: An emulsion polymerization process for the production of non-elastomeric fluoropolymers is disclosed wherein at least one fluorosurfactant is employed as dispersant, said fluorosurfactant being a fluoroalkylphosphoric acid ester of the formula X-Rf-(CH2)n—O—P(O)(OM)2, wherein n is 1 or 2, X?H or F, M=a univalent cation, and Rf is a C4-C6 fluoroalkyl or fluoroalkoxy group. Optionally, a second dispersing agent may be employed in the polymerization, said second agent being a perfluoropolyether having at least one endgroup selected from the group consisting of carboxylic acid, a salt thereof, sulfonic acid and a salt thereof, phosphoric acid and a salt thereof.

Abstract: To provide a method for producing a water/oil repellent composition which can impart water/oil repellency to a surface of an article and has excellent durability (wash durability and heavy-rain durability) and an article which has water/oil repellency and is less susceptible to deterioration of water/oil repellency when it is washed or in heavy rain. A method for producing a water/oil repellent composition which comprises polymerizing a monomer component comprising the following monomer (a) in coexistence with the following compound (x) in a medium in the presence of a surfactant and a polymerization initiator: monomer (a) is a compound of the formula (Z—Y)nX wherein Z is a C1-20 polyfluoroalkyl group or the like, Y is a bivalent organic group or a single bond, n is 1 or 2, and X is a polymerizable unsaturated group; and the compound (x) is a compound having at least two groups of —(CH2)a—CHR1—(CH2)b—SH, wherein R1 is a methyl group or an ethyl group, a is an integer of from 0 to 2, and b is 0 or 1.

Abstract: A polymer comprising recurring units of formula (1) and having a solubility in alkaline developer which increases under the action of an alkaline developer is provided. The polymer has transparency to radiation of up to 200 nm and improved water repellency, water slip, acid lability and hydrolysis and is useful as an additive polymer to formulate a resist composition. R1 is H, F, methyl, or trifluoromethyl, R2 is a monovalent fluorinated hydrocarbon group, An is a (n+1)-valent hydrocarbon or fluorinated hydrocarbon group, and n is 1, 2 or 3.

Abstract: Photopolymer-based dielectric materials are provided with methods for preparing the same. Composites and electronic devices including such dielectric materials also are provided.

Abstract: A process for polymerizing at least one fluorinated monomer in an aqueous polymerization medium in the presence of initiator and polymerization agent to form an aqueous dispersion of particles of fluoropolymer having a fluoropolymers solids content of at least about 10% by weight. The polymerization agent is a combination of fluoropolyether acid or salt thereof and siloxane surfactant. The aqueous polymerization medium contains less than about 300 ppm of perfluoroalkane carboxylic acid or salt fluorosurfactants.

Abstract: A repellent agent composition including an aqueous continuous phase and a graft copolymer dispersed in the aqueous continuous phase. The graft copolymer has a water soluble polymer trunk having hydroxyl groups and branches having fluorinated groups bonded to the polymer trunk at a carbon atom substituted with a hydroxyl group. Also disclosed is a method of making the graft copolymer and a substrate treated with the repellent composition.

Abstract: A fluorinated monomer has formula (1) wherein R1 is H, F, methyl or trifluoromethyl, R2 is a monovalent hydrocarbon group which may have halogen or oxygen, A is a divalent hydrocarbon group, and k1 is 0, 1 or 2. A polymer derived from the fluorinated monomer may be endowed with appropriate water repellency, water slip, acid lability and hydrolysis and is useful as an additive polymer in formulating a resist composition.

Abstract: A radiation-sensitive resin composition for liquid immersion lithography includes a resin component, a photoacid generator and a solvent. The resin component includes an acid-dissociable group-containing resin in an amount of more than 50% by mass. The acid-dissociable group-containing resin includes a repeating unit that includes a fluorine atom and an acid-dissociable group in a side chain of the repeating unit.

Abstract: A composition which provides surface effects to substrates comprising a polymer containing at least one urea linkage prepared by (i) reacting (1) at least one organic diioscyanate, polyisocyanate, or mixture thereof, and (2) at least one fluorochemical compound of Formula I Rf—O(CF2CF2)r(CH2CH2)q(R1)sXH??Formula (I) ?wherein Rf is a linear or branched C1 to C7 perfluoroalkyl optionally interrupted by one to three oxygen atoms, r is 1 to 3, q is 1 to 3, s is 0 or 1, X is O, S, or NR2 wherein R2 is H, or C1 to C6 alkyl, and R1 is a divalent radical selected from —S(CH2)n—, p is 1 to 50, and R3, R4 and R5 are each independently H or C1 to C6 alkyl; (ii) and then reacting with (3) water, a linking agent, or a mixture thereof.

Abstract: Photoresist additive polymers and photoresist formulations that can be used in immersion lithography without the use of an additional topcoat. The resist compositions include a photoresist polymer, at least one photoacid generator, a solvent; and a photoresist additive polymer. Also a method of forming using photoresist formulations including photoresist additive polymers.

Abstract: A polymerization initiator, a first polymerizable compound, and a second polymerizable compound are poured into a hollow of a first member (12). The first and second polymerizable compounds are copolymerized to produce a second member (16). The second member (16) is produced by forming a first layer (21) on an inner wall of the first member (12) and sequentially forming a layer over a precedingly formed layer. To form each layer, the first and second polymerizable compounds are put in the hollow of the first member (12), satisfying 1/99?W2/(W1+W2)?? when W1 is a weight of the first polymerizable compound, and W2 is a weight of the second polymerizable compound. The first and second polymerizable compounds are mixed such that the value of W2/(W1+W2) increases from the first layer (21) toward an nth layer.

Abstract: Copolymers prepared by copolymerization of at least one fluorinated vinyl ether are provided. In one embodiment, the at least one fluorinated vinyl ether comprises ethylene directly substituted at an olefinic carbon atom with a moiety —OR* and optionally substituted with one, two, or three additional nonhydrogen substituents, wherein R* comprises a fluorinated alkyl moiety substituted with a protected or unprotected hydroxyl group, and further wherein an atom within R* may be (i) taken together with one of the additional nonhydrogen substituents, if present, or (ii) directly bound to an olefinic carbon atom, to form a ring. The polymers are useful, for example, in lithographic photoresist compositions, particularly chemical amplification resists. In a preferred embodiment, the polymers are substantially transparent to deep ultraviolet (DUV) radiation, and are thus useful in DUV lithographic photoresist compositions.

Abstract: A porous membrane of vinylidene fluoride resin excellent in hydrophilicity and having a good balance among strength, elongation and water permeation rate, which is thus useful as a microfiltration membrane or a separator of battery. The porous membrane is formed from a copolymer of 100 mols of a vinylidene fluoride monomer and 0.01-10.0 mols of a hydrophilic monomer having at least one species of hydrophilic group selected from epoxy group, hydroxy group, carboxy group, ester group, amide group and acid anhydride group.

Abstract: The present invention provides a fluorinated polymer excellent in the crosslinking reactivity, crosslinked rubber physical properties and chemical resistance, and its crosslinked rubber. A fluorinated polymer comprising repeating units (a) based on at least one monomer selected from the group consisting of ethylenic unsaturated compounds each having a hydroxyphenyl group, repeating units (b) based on at least one fluoromonomer selected from the group consisting of tetrafluoroethylene, hexafluoropropylene, vinylidene fluoride, 3,3,3-trifluoropropene, 1,3,3,3-tetrafluoropropene, 1,1,2-trifluoroethylene, vinyl fluoride, 1,2-difluoroethylene and CF2?CF—O—Rf (wherein Rf is a C1-8 saturated perfluoroalkyl group or a perfluoro(alkoxyalkyl) group) and, if necessary, repeating units (c) based on at least one hydrocarbon monomer selected from the group consisting of ethylene, propylene and CH2?CH—O—R1.

Abstract: Disclosed is a method for producing a fluorine-containing copolymer composition wherein a fluorine-containing copolymer is produced by polymerizing 1-99 weight % of a monomer mixture (A) containing a polymerizable monomer having a fluoroalkyl group and a polymerizable monomer having a hydrophilic group in the presence of 1-99 weight % of a surfactant (B) containing a surfactant having an oxyalkylene group. The total amount of the monomer mixture (A) and the surfactant (B) is not less than 80 weight % of the polymerization system.

Abstract: The invention relates to a fluorine-containing compound represented by the formula 1, where R1 is a methyl group or trifluoromethyl group, each of R2 and R3 is independently a hydrogen atom or a group containing (a) a hydrocarbon group having a straight-chain, branched or ring form and having a carbon atom number of 1-25 or (b) an aromatic hydrocarbon group, the group optionally containing at least one of a fluorine atom, an oxygen atom and a carbonyl bond, l is an integer of from 0 to 2, each of m and n is independently an integer of 1-5 to satisfy an expression of m+n?6, and when at least one of R1, R2 and R3 is in a plural number, the at least one of R1, R2 and R3 may be identical with or different from each other.

Abstract: A process comprising polymerizing at least one fluorinated monomer in an aqueous medium containing initiator and polymerization agent to form an aqueous dispersion of particles of fluoropolymer, the polymerization agent comprising fluoropolyether acid or salt thereof having a number average molecular weight of at least about 800 g/mol; and fluoropolyether acid or salt surfactant.

Abstract: An FEP pellet having a volatile content of 0.2% by weight or less. The FEP pellet satisfies the following requirements (i) and (ii) when used to form a insulating material coating a core wire by extrusion coating at a coating speed of 2,800 ft/min.: (i) an adhesive strength between the insulating material and said core wire of 0.8 kg or more; and (ii) an average number of cone-breaks in the insulating material of one or less per 50,000 feet of the coated core wire.

Abstract: A surface-treating agent comprises a fluoropolymer comprising (A) repeating units derived from a fluorine-containing monomer of the formula: (B) repeating units derived from a monomer free from a fluorine atom, and (C) optionally, repeating units derived from a crosslinkable monomer. The surface treating agent is excellent in water repellency, oil repellency and unsusceptibility to fouling even when the side chains are C4 or lower fluoroalkyl groups.

Abstract: Embodiments of the present invention relate generally to non-self imagable and imagable norbornene-type polymers useful for immersion lithographic processes, methods of making such polymers, compositions employing such polymers and the immersion lithographic processes that make use of such compositions. More specifically the embodiments of the present invention are related to norbornene-type polymers useful for forming imaging layer and top-coat layers for overlying such imaging layers in immersion lithographic process and the process thereof.

Abstract: Disclosed is a fluorine-containing polymer compound containing first and second repeating units respectively represented by formulas (a-1) and (a-2), wherein R3 represents a fluorine atom or fluorine-containing alkyl group, each of W and W1 independently represents a bivalent linking group, R2 represents an acid-labile protecting group, each of R4, R5 and R6 independently represents a hydrogen atom, fluorine atom or monovalent organic group, and at least two of R4, R5, R6 and W or W1 may be combined to form a cyclic structure in formula (a-1) or (a-2). This polymer compound has a weight-average molecular weight of 1,000 to 1,000,000 and can provide a resist composition capable of forming a pattern with no swelling and no pattern falling down.

Abstract: A polymerization medium having small ozone depletion potential and small global warming potential and having a small chain transfer constant is used, to efficiently produce a fluoropolymer having a high molecular weight and having excellent heat resistance, solvent resistance, chemical resistance, etc. A process for producing a fluoropolymer, which comprises polymerizing a fluoromonomer having a carboxylic acid type functional group and a fluoroolefin using a hydrofluorocarbon as a medium, wherein the hydrofluorocarbon as the medium has 4 to 10 carbon atoms and has a ratio (molar basis) of the number of hydrogen atoms/the number of fluorine atoms (H/F ratio) of from 0.05 to 20.

Abstract: Melt-processible, thermoplastic poly(tetrafluoroethylene) (PTFE) compositions are disclosed and methods for making and processing same. Additionally, products comprising these compositions are described.

Abstract: A fluorine-containing polymer comprising a fluoroalkyl alcohol (meth)acrylic acid derivative represented by a general formula, CnF2n+1(CH2CF2)a(CF2CF2)b(CH2CH2)cOCOCR?CH2 (in the formula, R is a hydrogen atom or a methyl group, n is an integer of 1 to 6, preferably 2 to 4, a is an integer of 1 to 4, b is an integer of 0 to 3, and c is an integer of 1 to 3) containing in 5 to 100 wt % as a polymerization unit. A organic solvent solution or aqueous dispersion of the fluorine-containing polymer is effectively used as, for example, a surface-modifying agent such as a water- and oil-repellent or an oil barrier.

Abstract: Provided are functionalized nanodiamonds. Also provided are methods for fabricating such functionalized nanodiamonds. Also provided are composites including nanodiamonds and polymers. Also provided are methods for fabricating such composites including nanodiamonds and polymers. Also provided are electrospun fibers including nanodiamonds and polymers. Also provided are methods for fabricating such electrospun fibers including nanodiamonds and polymers.

Abstract: A method of polymerizing poly(cyclic)olefin monomers encompassing (a) combining a monomer composition containing the poly(cyclic)olefin monomers, a non-olefinic chain transfer agent and an activator compound to form a mixture; (b) heating the mixture; and (c) adding a polymerization catalyst containing Ni and/or Pd. The non-olefinic chain transfer agent includes one or more compounds selected from H2, alkylsilanes, alkylalkoxysilanes, alkylgermanes, alkylalkoxygermanes, alkylstannanes, and alkylalkoxystannanes. The activator is characterized as having an active hydrogen with a pKa of at least 5. The resulting poly(cyclic)olefin polymers can be used in photoresist compositions.

Abstract: To provide a copolymer which can impart sufficient dynamic water repellency, after air-drying water repellency and friction durability to a surface of an article, and which has low impact on the environment, a method for producing the same, a water repellent composition and an article excellent in dynamic water repellency, after air-drying water repellency and friction durability.

Abstract: This invention relates to a process comprising contacting an polymerization reactor effluent with a fluorinated hydrocarbon and thereafter recovering olefin polymer, where the fluorinated hydrocarbon is present at 5 volume % to 99 volume % based upon the volume of the effluent and the fluorinated hydrocarbon, and where the polymerization is a continuous polymerization of at least 75 mole % of hydrocarbon monomers, based upon the total moles of monomer present in the reactor.

Abstract: The invention pertains to a multi-phase thermoplastic fluoropolymer composition, comprising a thermoplastic fluoropolymer and discrete domains of melt-processable perfluoropolymer, to the articles therefrom and to a process for manufacturing thermoplastic fluoropolymer compositions. The multi-phase thermoplastic fluoropolymer composition comprises: —at least one thermoplastic fluoropolymer (A); and —from 0.1 to 10% by weight of (A) of at least one melt-processible perfluoropolymer (B), and is characterized in that the polymer (B) is present in the composition in phase-separated domains in a continuous phase mainly comprising (A), at least 75% by volume of said domains having maximal dimension not exceeding 1 ?m. The process of the invention comprises mixing: (i) a thermoplastic fluoropolymer (A); (ii) a melt-processible perfluoropolymer (B) under the form of particles having an average primary particle size not exceeding 300 nm; (iii) and optionally other additives or filling materials.

Abstract: A composition comprises a copolymer comprising repeating units derived from at least one co-reactant comprising two or more acrylate groups and repeating units derived from a fluoroacrylate comprising the reaction product of: (a) at least one fluorochemical alcohol represented by the formula: C4F9—X—OH wherein: R=hydrogen or an alkyl group of 1 to 4 carbon atoms, m=2 to 8, Rf?CnF2n+1, n=1 to 5, y=0 to 6, and q=1 to 8; (b) at least one unbranched symmetric diisocyanate; and (c) at least one hydroxy-terminated alkyl (meth)acrylate or 2-fluoroacrylate monomer having 2 to about 30 carbon atoms in its alkylene portion; wherein the composition is coatable.

Abstract: The liquid immersion lithography process is configured so that the resist pattern resolution is improved by exposing a resist film to the lithographic exposure light under the conditions in which the predetermined thickness of the liquid for liquid immersion lithography, of which the refractive index is higher than that of air and smaller than that of the resist film is intervened at least on the resist film in a path of the lithography exposure light reaching the resist film, a protective film is formed on the surface of the resist film to be used. Therefore, when various immersion liquid, water being the representative example is used in the liquid immersion lithography process can be formed, the deterioration of the resist film and the immersion liquid to be used are simultaneously prevented, and the number of the process steps are not increased, and then the resist pattern having higher resolving ability.

Abstract: There is provided a curable surface modifier comprising a resin which is soluble in a general purpose solvent and comprises a fluorine-containing ethylenic polymer containing, in at least a part of its side chain, a moiety A having a long polyfluoropolyether chain and/or a moiety B having a self-crosslinkable functional group, in which the resin contains both of the moieties A and B. The curable surface modifier improves properties of surfaces of various coating films, especially antireflection films, such as surface sliding property (decrease in a friction coefficient), surface hardness, abrasion resistance, chemical resistance and stain removability by wiping, thus being capable of imparting modified properties to the surfaces of original coating films.

Abstract: The invention provides a fluorinated surfactant having the general formula: [Rf—(O)t—CHF—(CF2)n—COO—]iXi+??(I) wherein Rf represents a partially or fully fluorinated aliphatic group optionally interrupted with one or more oxygen atoms, t is 0 or 1 and n is 0 or 1, Xi+ represents a cation having a valence i and i is 1, 2 or 3. The surfactant can be used in emulsion polymerization of fluoromonomers to prepare fluoropolymers.

Abstract: VDF-based curable fluorelastomers, having a glass transition temperature from ?10° C. to ?35° C., comprising: B) monomer of formula: CF2?CFOCF2OCF3 (a), C) one or more comonomers selected from: tetrafluoroethylene (TFE), per-fluoromethylvinylether (PMVE), perfluoropropene (HFP), and an amount of —COF end groups in the polymer lower than the sensitivity limit of the method which uses the FT-IR spectroscopy described in the present application.

Abstract: Improved expanded PTFE materials and improved gasket materials made therefrom, the gaskets being capable of forming a seal with greater bolt load retention than is possible with existing PTFE gaskets. The expanded PTFE membranes of the invention can be tailored to exhibit a matrix tensile strength in at least one direction of at least 25,000 psi, a matrix tensile strength ratio in two orthogonal directions of between 0.25 and 4, an orientation index of 50° or less, and a density of 2.0 g/cc or less. The improved gaskets exhibit improved mechanical properties such as high bolt load retention, low creep, high tensile strength, low stress to seal and high crystallinity index.

Abstract: Improved expanded PTFE materials and improved gasket materials made therefrom, the gaskets being capable of forming a seal with greater bolt load retention than is possible with existing PTFE gaskets. The expanded PTFE membranes of the invention can be tailored to exhibit a matrix tensile strength in at least one direction of at least 25,000 psi, a matrix tensile strength ratio in two orthogonal directions of between 0.25 and 4, an orientation index of 50° or less, and a density of 2.0 g/cc or less. The improved gaskets exhibit improved mechanical properties such as high bolt load retention, low creep, high tensile strength, low stress to seal and high crystallinity index.

Abstract: Fluoroelastomer gum or crumb is isolated from fluoroelastomer dispersions by the addition of a water-soluble polymeric coagulating agent to the dispersion. This coagulating agent comprises either a homopolymer of ethylene oxide (CH2CH2O—) or a copolymer of ethylene oxide. Specific examples of such copolymers include, but are not limited to ethylene oxide-propylene oxide copolymers and ethylene oxide-butylene oxide copolymers. The viscosity average molecular weight (Mv), determined by rheology, of the coagulant polymer must be at least 500,000 and preferably greater than 2,000,000.

Abstract: The current invention relates to a fluorinated elastomer latex containing an aqueous medium, a fluorinated elastomer dispersed in the aqueous medium in an amount of from 10 to 60 mass % and a fluorinated emulsifier represented by the formula (1): C2F5O(CF2CF2O)mCF2COOA (wherein A is a hydrogen atom, an alkali metal or NH4, and m is an integer of from 1 to 3), which employs no perfluorooctanoate emulsifier and which is excellent in dispersion stability of the fluorinated elastomer.

Abstract: Disclosed is a water-repellent oil-repellent antifouling agent containing a fluorine-containing polymer for a treatment for providing water repellency, oil repellency and antifouling property. The fluorine-containing polymer has a repeating unit (A) derived from a fluorine-containing acrylate monomer, and a repeating unit (B) derived from at least one non-fluorine acrylate monomer selected from the group consisting of a monomer (B1) having a cyclic hydrocarbon group and a monomer (B2) having a short chain hydrocarbon group. This water-repellent oil-repellent antifouling agent has good solubility in solvents, and exhibits excellent effects on various bases, especially on masonries.

Abstract: A process for reducing the fluorosurfactant content of an aqueous fluoropolymer dispersion by filling a shipping container with fluoropolymer dispersion and contacting the dispersion with a fluorosurfactant sorbent in the shipping container.

Abstract: Polymer ion-exchange membranes having outstanding electrical conductivity, water retention and oxidation resistance are produced by the steps of uniformly mixing an organic high-molecular weight resin with functional inorganics having the abilities to promote graft polymerization of polymerizable monomers, adsorb water and conduct protons, irradiating the resulting functional inorganics/polymer membrane to initiate graft polymerization or graft copolymerization of polymerizable monomers having functional groups, and then introducing sulfonic acid groups into the graft chains.

Abstract: The present invention provides an aqueous emulsion polymerization of fluorinated monomers including gaseous fluorinated monomers using a perfluoro ether surfactant as an emulsifier. The perfluoro ether surfactants correspond to formula (I) Rf—O—CF2CF2—X??(I) wherein Rf represents a linear or branched perfluoroalkyl group having 1, 2, 3 or 4 carbon atoms and X represents a carboxylic acid group or salt thereof. In a further aspect, the invention also provides an aqueous fluoropolymer dispersion comprising the perfluoro ether surfactant and the use of such dispersion in the coating or impregnation of substrates.

Abstract: The present invention relates to, for example, a fluorine-containing cyclic compound represented by the following general formula (1). In the general formula (1), R1a is a C1-C25 cyclic alkyl group, cyclic alkenyl group or cyclic alkynyl group; each of R2 and R3 is independently a hydrogen atom, a halogen atom, or a C1-C25 straight-chain, branched or cyclic alkyl group; and each of R1a, R2 and R3 may contain fluorine atom, oxygen atom, sulfur atom, nitrogen atom or an atomic group containing a carbon-carbon double bond.

Abstract: VDF curable fluoroelastomers, ionically cured, having a compression set after a time of 24 h (ASTM D 39/B) at ?10° C. lower than 60%, preferably lower than 50% and at ?25° C. lower than 90%, preferably lower than 75%, comprising hexafluoropropene (HFP) in amounts higher than 10% by moles and one vinylether of formula: CF2?CFOCF2OCF3 (a), an amount of —COF and groups in the polymer lower than the sensitivity limit of the method using the FT-IR spectroscopy described in the present application.

Abstract: VDF-based curable fluoroelastomers, having a glass transition temperature lower than ?49° C., preferably lower than ?50° C., and having the following composition, as percent moles: A) from 25% to 50%, preferably from 30% to 45%, of the monomer of formula: CF2?CFOCF2OCF3 (a); B) one or more (per)fluorinated comonomers having at least one unsaturation of ethylene type in amounts from 75% to 50%; preferably from 70% to 55%; said one or more comonomers comprising vinylidene fluoride (VDF) in amounts from 50% to 75% on the total of the monomer moles; the sum of the molar percentages of the monomers being 100%; said fluoroelastomers containing an amount of —COF end groups in the polymer lower than the sensitivity limit of the method reported in the description.

Abstract: A method of controlling the molecular weight of poly(cyclic)olefin (norbornene-type) polymers and activating the polymerization thereof with a single material is provided. Such method include adding a chain transfer/activating agent to a mixture of monomer(s), catalyst, solvent and an optional cocatalyst and polymerizing the mixture to form a polymer. It is shown that the amount of chain transfer/activating agent in the mixture can serve to control the molecular weight of the resulting polymer, its percent conversion or both, and in some embodiments the optical density of the resulting polymer.