摘要:
The present invention provides a process for preparing a fluorine-containing polymer having few branched chains and little weight change in high temperatures, which is a new process wherein composition distribution substantially does not occur. The fluorine-containing polymer is prepared by a batch copolymerization process conducted under conditions of reduced temperature of at least 0.95 and reduced pressure of at least 0.80 of the critical constant calculated from critical temperature, critical pressure and composition ratio of each monomer in the gaseous phase of the reaction vessel using the Peng-Robinson formula; wherein when the number of monomer components in the target polymer is represented as n (n is an integer of 2 or larger), the name of each monomer component is represented as A1, A2, . . . An, the weight percentage of each monomer component A1, A2, . . . An of the target polymer composition is represented as a1, a2, . . . an (%) (a satisfies ∑ n a n = 100 ) , the weight percentage of each monomer component of the initial monomer composition is represented as a′1, a′2 . . . a′n (%) (a′ satisfies ∑ n a n ′ = 100 and a′1, a′2, . . . a′n is determined in a constant manner depending on predetermined polymerization conditions) and specific gravity of the gaseous phase monomers when polymerizing/specific gravity of the target polymer is represented as B, the composition weight ratio of additional monomers is calculated for each monomer from the formula (a1−a′1×B):(a2−a′2×B) . . . (an−a′n×B) in the order of components A1, A2, . . . An, and additional monomers containing additional monomers in the composition weight ratio of additional monomers are added.
摘要:
There is provided a method of end-chlorination of a fluorine-containing compound which can easily provide a fluorine-containing monomer having a functional group such as nitrile group at relatively low cost. The method of chlorinating an end of a fluorine-containing compound having iodine atom at an end thereof comprises reacting a fluorine-containing organic compound having iodine atom at a molecular end thereof and represented by the formula (I): RfCX2I (I) wherein Rf is an organic residue having fluorine atom, X is hydrogen atom or chlorine atom, with a chlorine gas at a temperature of from 150° C. to 180° C. under irradiation with light to cleave the C—I bond and replace iodine atom with chlorine atom.
摘要:
To provide a solid fluoroelastomer having nitrile group at the end which gives a crosslinked product being excellent in heat resistance, solvent resistance, chemical resistance, compression set and cleanliness, and an economical process for preparation thereof. The process for preparing a nitrile group-containing fluoroelastomer by converting amide group contained in a polymer molecular chain of a solid fluoroelastomer into nitrile group in the presence of a dehydrating agent.
摘要:
The present invention relates to a ceramics composite including an inorganic material which includes: a matrix phase including a translucent ceramics; and a phosphor phase including YAG containing Ce, in which a content of the phosphor phase is from 22% by volume to 55% by volume based on the whole phase including the matrix phase and the phosphor phase, a content of Ce in the YAG is 0.005 to 0.05 in terms of an atomic ratio of Ce to Y (Ce/Y), and the ceramics composite has a thickness in a light outgoing direction of 30 μm to 200 μm.
摘要:
The present invention relates to a ceramics composite including an inorganic material which includes: a matrix phase including a translucent ceramics; and a phosphor phase including YAG containing Ce, in which a content of the phosphor phase is from 22% by volume to 55% by volume based on the whole phase including the matrix phase and the phosphor phase, a content of Ce in the YAG is 0.005 to 0.05 in terms of an atomic ratio of Ce to Y (Ce/Y), and the ceramics composite has a thickness in a light outgoing direction of 30 μm to 200 μm.
摘要:
The present invention provides a process for preparing a fluorine-containing polymer having few branched chains and little weight change in high temperatures, which is a new process wherein composition distribution substantially does not occur. The fluorine-containing polymer is prepared by a batch copolymerization process conducted under conditions of reduced temperature of at least 0.95 and reduced pressure of at least 0.80 of the critical constant calculated from critical temperature, critical pressure and composition ratio of each monomer in the gaseous phase of the reaction vessel using the Peng-Robinson formula.
摘要:
The present invention provides a process for selectively separating HF and like acids present along with water-unstable organic acid fluorides. In particular, the invention provides a process for separating an acid from a system in which the acid and an organic acid fluoride are present, the organic acid fluoride being represented by formula (I): RCOF (I) wherein R is a fluorine atom; a C1-20 linear, branched or cyclic alkyl or halogenated alkyl group that may contain a heteroatom; or a C6-20 aryl or halogenated aryl group that may contain a heteroatom; the process comprising using as a deacidifying agent an aromatic heterocyclic compound having a boiling point of at least 50° C. and having one or more nitrogen atoms as heteroatom.
摘要:
The present invention provides a process for preparing a fluorine-containing elastomer in a high productivity comparable to that of non-iodine transfer polymerization process by carrying out an iodine transfer polymerization at high pressure. The present invention also provides a fluorine-containing elastomer prepared by this process, and fluorine-containing molded articles. The process is a batch copolymerization process conducted under conditions that the reduced temperature of the critical constant is at least 0.95 and the reduced pressure of the critical constant is at least 0.80 wherein the reduced temperature and the reduced pressure are calculated using the Peng-Robinson formula from the critical temperature, the critical pressure and the composition ratio of each of the monomers in the gaseous phase in a reaction vessel, in which ethylenically unsaturated compounds containing at least one fluoroolefine are copolymerized in the presence of a compound having the formula: Rf1.Ix wherein Rf1 is a saturated or unsaturated fluorohydrocarbon or chlorofluorohydrocarbon group having 1 to 16 carbon atoms, and x is the number of bonds of Rf1 and an integer of 1 to 4.
摘要:
To provide a novel crosslinking system of fluorine-containing elastomer giving a crosslinked product particularly having improved mechanical strength and compression set at high temperature. A fluorine-containing rubber composition comprising a fluorine-containing elastomer having carboxyl group and/or alkoxycarbonyl group at an end of a trunk chain and/or branched chain as a crosslinkable group.
摘要:
The present invention provides the process for preparing a fluorine-containing polymer which can easily and efficiently separate a fluorine-containing polymer and water from an aqueous dispersion of a fluorine-containing polymer, and the fluorine-containing polymer obtained by the mentioned preparation process. Further the present invention provides the molded article obtained by crosslinking a curable composition comprising the above-mentioned fluorine-containing polymer and a crosslinking agent. The preparation process is a process for preparing a fluorine-containing polymer comprising a step for heat-treating an aqueous dispersion of a fluorine-containing polymer having a concentration of 3 to 70% by weight to obtain the fluorine-containing polymer having a water content of not more than 1% by weight.