摘要:
A transparent thermoplastic molding compound consisting of 40 to 90% by weight of units derived from tetrafluoroethylene, and 60 to 10% by weight of units derived from compounds of formula I or II:CF.sub.2 .dbd.CF--O--(CF.sub.2 --CF(CF.sub.3)--O).sub.m --(CF.sub.2).sub.n --CF.sub.3 (I)CF.sub.2 .dbd.CF--O--(CF.sub.2 --CF(CF.sub.3)--O).sub.p --(CF.sub.2).sub.q --COO--R (II)is particularly suitable for manufacturing the sheath of beam waveguides whose core has a higher transparency than polymethyl methacrylate.
摘要:
Fluorinated carboxylic acid fluorides of the formula I ##STR1## can be prepared from fluorinated vinyl ethers of the formula II ##STR2## by reacting the vinyl ethers with an oxygen-containing gas in the presence of a catalytic amount of a Lewis acid. Perfluorinated carboxylic acids and derivatives thereof can be prepared from the carboxylic acid fluorides by secondary reactions, for example hydrolysis, esterification or aminolysis.
摘要:
The invention relates to solutions of fluoropolymers which preferably contain carbonate groups, in solvents of the general formula (I) ##STR1## These solutions are suitable, in particular, for the production of membranes for liquid permeation processes, such as electrolysis.
摘要:
A trifluoroacrylate has been prepared by reacting hexafluoropropene with halogen fluorosulfate (halogen X:Cl, Br or I), eliminating the fluorosulfate CF.sub.3 --CFX--CF.sub.2 --OSO.sub.2 F to give the acid fluoride CF.sub.3 --CFX--COF, esterifying the acid fluoride and dehalogenating the product using a metal component.
摘要:
Solutions of copolymers of the tetrafluoroethylene/ethylene typeCopolymer solutions comprising tetrafluoroethylene, ethylene and, as appropriate, further .alpha.-olefinic monomers in low-molecular-weight polymers of chlorotrifluoroethylene are described. They can be used for coatings, impregnations, cast films and for the production of fibers and filaments by gel spinning.
摘要:
Process for the preparation of fluorinated carboxylic acid fluoridesFluorinated carboxylic acid fluorides of the Formula I ##STR1## can be prepared from fluorinated vinyl ethers of the Formula II ##STR2## by heating the vinyl ethers to a temperature of 100.degree. to 350.degree. C.Perfluorinated carboxylic acids and derivatives thereof can be prepared from the carboxylic acid fluorides by secondary reactions, for example hydrolysis, esterification or aminolysis.
摘要:
Described herein is a composition comprising: a polymer derived from (a) a fluorinated olefin monomer; (b) a highly fluorinated sulfur-containing monomer of the formula: CX1X2═CX3[(CX4X5)w—O—R1—SO2Y] where X1, X2, X3, X4, and X5 are independently selected from H, Cl, or F; w is 0 or 1; R1 is a non-fluorinated or fluorinated alkylene group; and Y is selected from F, Cl, Br, I, or OM, where M is a cation; and (c) a polyfunctional monomer comprising at least two functional groups, wherein the functional groups are selected from the group consisting of: (i) a fluorovinyl ether group, (ii) a fluoroallyl ether group, (iii) a fluorinated olefinic group, and (iv) combinations thereof; articles thereof; and a method of making such polymers.
摘要:
The present disclosure describes fluoropolymers having long chain branches and methods of making these fluoropolymers. These fluoropolymers may have improved melt processing properties. Shaped articles containing these fluoropolymers are also provided.
摘要:
A method for preparing fluorinated carboxylic acids and theirs salts is described comprising subjecting a fluorinated to at least one first and at least one second oxidizing agent to produce a highly fluorinated carboxylic acid or their salts. The first oxidizing agent is a compound that can be converted, by action of the second oxidizing agent, into a reactive species capable of oxidizing the fluorinated alcohol.