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 method of making a fluoropolymer dispersion by first providing a fluoropolymer dispersion comprising fluoropolymer particles and one or more fluorinated surfactants selected from fluorinated carboxylic acids or salts thereof having the general formula: [Rf—O-L-COO−]iXi+ (I) wherein L represents a linear partially or fully fluorinated alkylene group or an aliphatic hydrocarbon group, Rf represents a linear partially or fully fluorinated aliphatic group or a linear partially or fully fluorinated aliphatic group interrupted with one or more oxygen atoms, Xi+ represents a cation having the valence i and i is 1, 2 or 3; then adding one or more non-fluorinated surfactants selected from anionic and non-ionic surfactants followed by reducing the total amount of the one or more fluorinated surfactants to an amount of not more than 500 ppm, for example not more than 250 ppm based on the total weight of the dispersion while maintaining or increasing the amount of solids in the dispersion.
摘要翻译:首先提供含氟聚合物颗粒和一种或多种选自氟化羧酸或其盐的含氟表面活性剂的含氟聚合物分散体的制备方法,所述含氟聚合物分散体具有以下通式:[Rf-OL-COO-] iXi +(I)其中L表示 线性部分或完全氟化的亚烷基或脂族烃基,Rf表示直链部分或完全氟化的脂族基团或被一个或多个氧原子间隔的线性部分或全部氟化脂族基,X i +表示具有i价和 我是1,2或3; 然后加入一种或多种选自阴离子和非离子表面活性剂的非氟化表面活性剂,然后将一种或多种氟化表面活性剂的总量减少至不超过500ppm,例如不超过250ppm,基于 分散体的总重量,同时保持或增加分散体中固体的量。
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.
摘要:
A coating composition having (i) an aqueous dispersion of fluoropolymer particles comprising a non-melt processible polymer of tetrafluoroethylene, (ii) a fluorinated surfactant, (iii) a non-ionic non-fluorinated surfactant and (iv) a non-fluorinated polymer, wherein the fluorinated surfactant is selected from fluorinated carboxylic acids or salts thereof of the general formula (I): [Rf—O-L-COO−]iXi+ (I) wherein L represents a linear partially or fully fluorinated alkylene group or an aliphatic hydrocarbon group, Rf represents a linear partially or fully fluorinated aliphatic group or a linear partially or fully fluorinated aliphatic group interrupted with one or more oxygen atoms, Xi+ represents a cation having the valence i and i is 1, 2 or 3.
摘要:
A process for the recovery of fluorinated carboxylic acid or derivative thereof from adsorbent particles on which fluorinated carboxylic acid or a salt thereof is adsorbed. The process includes contacting the adsorbent particles with a liquid composition capable of removing at least part of the fluorinated carboxylic acid or salt thereof from the adsorbent particles. The fluorinated carboxylic acid or salt thereof is selected from the group consisting of fluorinated carboxylic acids or salts thereof that correspond to the general formula: [RfO-L-COO−]iXi+ (I) wherein L represents a linear partially or fully fluorinated alkylene group or an aliphatic hydrocarbon group, Rf represents a linear partially or fully fluorinated aliphatic group or a linear partially or fully fluorinated aliphatic group interrupted with one or more oxygen atoms, Xi− represents a cation having the valence i and i is 1, 2 or 3.
摘要:
The present invention provides a process for oligomerization of hexafluoropropylene oxide, the process comprising polymerizing a mixture of hexafluoropropylene oxide and hexafluoropropene in the presence of an aprotic organic solvent using KF as a catalyst.
摘要:
The present invention provides a method of removing a fluorinated surfactant from waste water comprising fluoropolymer particles. The method comprises (i) adding a non-fluorinated surfactant to the waste water (ii) contacting the thus obtained waste water with adsorbent particles to adsorb at least a portion of the fluorinated surfactant to the adsorbent particles and (iii) separating the waste water and the adsorbent particles.