摘要:
This invention concerns functional fluorine-containing copolymers compositions and ionomers derived therefrom. The ionomers formed are useful in electrochemical applications such as batteries, fuel cells, in exchange membranes, sensors and the like.
摘要:
A fluorocopolymer which comprises (A) polymerized units based on tetrafluoroethylene, (B) polymerized units based on ethylene and (C) polymerized units based on a compound represented by CH2═CX(CF2)2Y (wherein each of X and Y which are independent of each other, is a hydrogen atom or a fluorine atom), wherein the molar ratio of (A)/(B) is from 20/80 to 80/20, and the molar ratio of (C)/((A)+(B)) is from 1/1000 to 15/100, and which has a volume flow rate of from 1 to 1000 mm3/sec. The fluorocopolymer has a low fuel permeability coefficient and is excellent in the fuel barrier properties.
摘要:
This invention is directed to optical adhesives useful in light transmitting devices, and more particularly to fluorosubstituted monoacrylate based adhesives having low refractive index. The optical adhesive of the present invention is soluble in organic solvents, and in particular, in non-fluorinated organic solvents. The polymer of the optical adhesive of the present invention has a low glass transition temperature and has the ability to bond well with substrates, including glass substrates and polyethylene terephthalate polyester film substrates typically used in optical devices. The invention is further directed to transfer tapes comprised of at least one layer of a fluorosubstituted monoacrylate based adhesive.
摘要:
Chain transfer agents that are chlorine-free and liquid under polymerization conditions, useful for fluoromonomer polymerization, have the following formula: R1—O—R2. They are superior to common chain transfer agents such as chloroform in being safer and environmentally benign. They are also superior to gaseous chain transfer agents such as ethane because they do not enter the fluoromonomer gas recycle streams and so do not complicate the analysis and purification of those streams.
摘要:
A fluoropolymer having a reduced amount of polar end groups. The fluoropolymer is produced by free radical polymerization of fluorinated monomers and the initiation of the polymerization is carried out in the presence of a chloride salt. Polar end groups include hydroxy groups and ionized or ionizable end groups. Examples of ionized or ionizable end groups include acid groups and salts thereof such as sulfonic acid and salts thereof, —CH2—OSO3H groups, sulfates and carbonyl containing end groups such as carboxylic and carboxylate groups. Due to the presence of chloride salt at the initiation of the free radical polymerization, CF2Cl end groups are formed instead of the polar end groups. As a result, a fluoropolymer is obtained that has improved processibility and heat resistance.
摘要:
Functional trifluorovinyl monomers, process for the copolymerization of trifluorovinyl monomers with fluoroolefins and use of these trifluorovinyl monomers in forming fluoroelastomers. Copolymers resulting from this copolymerization process and process for crosslinking these copolymers.
摘要:
A fluorochemical composition for rendering a fibrous substrate oil and/or water repellent which comprises a solution or dispersion of a fluoropolymer having a partially or fully fluorinated backbone and comprising one or more repeating units corresponding to the general formula: wherein Rf represents a perfluorinated organic group having a chain length of at least 2 atoms and having at least one carbon atom and optional auxiliary components.
摘要:
A process for preparing a fluoropolymer by polymerizing one or more radically polymerizable monomers comprising at least one fluoroolefin monomer in the presence of a radical polymerization initiator and as case demands, an inactive fluorocarbon and chain transfer agent in a reaction field where at least one of components forming the reaction field is in a supercritical state. According to the preparation process, generation of unstable end groups of the polymer, a decrease in a purity and complicated post-treatment can be eliminated.
摘要:
A fluorine-containing elastomer composition comprising a terpolymer of tetrafluoroethylene, perfluoro(lower alkyl vinyl ether) and perfluoro(&ohgr;-cyanoalkyl vinyl ether) and a bisaminophenyl compound represented by the following general formula as a curing agent: wherein A is an alkylidene group having 1 to 6 carbon atoms, a perfluoroalkylidene group having 1 to 10 carbon atoms, a SO2 group, an O group, a CO group, or a carbon-carbon bond capable of directly coupling two benzene rings; and X and Y each are a hydroxyl group or an amino group can give a rubbery vulcanization product with a good processability and good physical properties by a commercially available cross-linking agent free from any safety problem.
摘要:
Melt-processible, thermoplastic poly(tetrafluoroethylene) (PTFE) compositions are disclosed and methods for making and processing same. Additionally, products comprising these compositions are described.