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.
摘要:
A method for preparing fluorinated carboxylic acids and theirs salts is described comprising subjecting a fluorinated alcohol of the general formula (A): A-CH2—OH to at least one first and at least one second oxidizing agent to produce a highly fluorinated carboxylic acid or their salts of the general formula (B): A-COO M+, wherein M+ represents a cation and wherein A in formulas (A) and (B) is the same and A represents the residue: Rf-[0]p-CX″Y″-[0]m-CX′Y′-[0]n-CXY— wherein Rf represents a fluorinated alkyl residue which may or may not contain one or more catenary oxygen atoms, p, m and n are independently from each other either 1 or O, X, X′, X″, Y, Y′ and Y″ are independently from each other H, F, CF3, or C2F5 with the proviso that not all of X, X′, X″, Y, Y′ and Y″ are H; or A represents the residue: R—CFX— wherein X and R are independently selected from a hydrogen, a halogen, or an alkyl, alkenyl, cycloalkyl, or aryl residue, which may or may not contain one or more fluorine atoms and which may or may not contain one or more catenary oxygen atoms; wherein said at least one 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.
摘要:
The present invention provides a curable fluoroelastomer composition comprising: (a) a fluoroelastomer comprising a cure site component having a halogen capable of participation in a peroxide cure reaction; (b) an organic peroxide; and (c) a siloxane or silazane comprising one or more —SiH groups. The curable fluoroelastomer compositions generally show improved processing and the resulting cured fluoroelastomers generally have improved mechanical and physical properties.
摘要:
A composition and method for making a fluoroelastomer is disclosed. The composition comprises a fluoroelastomer containing chlorine and an organic compound containing at least an hydride function. The hydride function has the formula MH where M is Si, Ge, Sn or Pb.
摘要:
The present invention provides a curable composition comprising a fluoropolymer comprising interpolymerized units derived from (i) CF2═CF—Rf, wherein Rf is fluorine or a C1-C8 perfluoroalkyl, (ii) at toast about 10 mole percent of a hydrogen-containing C2-C9 olefin, based on the total moles of said CF2═CFRf and said olefin, (iii) an average of two or more bromine atoms including one or more terminal bromine atom(s) per fluoropolymer chain, (iv) optionally CX2═CX—R, wherein each X is independently H, F, or Cl and R is a halogen or a C1-C8 alkyl or alkenyl group that may include one or more ether linkage(s), (v) optionally a bromine-containing cure site monomer; (b) optionally, a peroxide curing agent; and (c) optionally, a crosslinking co-agent. The invention also provides methods of making and using such fluoropolymer compositions.
摘要:
Method of making fluoropolymers by emulsion polymerization of one or more fluorinated monomers in an aqueous phase in the presence of a fluorinated emulsifier, said method comprises adding a doping agent in a weight ratio with respect to the emulsifier of from about 1:2 to about 1:20, said doping agent has a melting point of equal or less than 30° C. and a boiling point of at least about 100° C. and is selected from the group consisting of fluorinated cyclic hydrocarbons, fluorinated polyoxyalkenes, fluorinated alkenes and fluorinated polyoxyalkenes.
摘要:
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.
摘要翻译:本发明提供具有以下通式的氟化表面活性剂:[Rf-(O)t-CHF-(CF 2)n -CO 2 - ] i X i +(I)其中R f表示部分或完全氟化的脂族基团,任选被一个或多个氧 原子,t为0或1,n为0或1,Xi +表示i为i且i为1,2或3的阳离子。表面活性剂可用于含氟单体的乳液聚合以制备含氟聚合物。
摘要:
The invention provides a method for recovery of a fluorinated anionic surfactant from a basic anion exchange resin having quaternary ammonium groups, the method comprising eluting the anion exchange resin with a composition comprising an ammonium salt and a water miscible organic solvent. The method according to the invention may provide one or more of the following advantages. For example, the method can be designed to allow for recovery of substantially all of the fluorinated surfactant from a basic anion exchange resin having quaternary ammonium groups. Also, the liquid used for recovering the surfactant from the anion exchange resin is a simple liquid that can be readily and cost effectively manufactured. Further the process may be carried out in a convenient and easy manner. Furthermore, the method generally does not require large amounts of the eluting composition.
摘要:
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.
摘要:
A process comprising polymerizing tetrafluoroethylene in an aqueous emulsion in the presence of a non-telogenic surfactant having an anionic portion with the general formula (I): Rf—O-L-CO2— (I) wherein Rf is selected from a partially fluorinated alkyl group, a perfluorinated alkyl group, a partially fluorinated alkyl group interrupted by one or more oxygen atoms, and a perfluorinated alkyl group interrupted by one or more oxygen atoms, wherein Rf has from 1 to 10 carbon atoms; and L is an alkylene group having the general formula (CX2)n wherein each X is independently selected from Rf, fluorine, and hydrogen and n is selected from 1 to 5, with the proviso that the surfactant contains at least one unit selected from a —CH2— unit and a —CHF— unit. Also provided are aqueous dispersions comprising these surfactants and methods of coating substrates with the aqueous dispersions.