Fluoropolymer compositions and purification methods thereof
Described herein is a composition comprising an aqueous polymerization reaction product of fluorinated monomers and wherein the polymerization is initiated (i) in the absence of a fluorinated emulsifier and whereby no fluorinated emulsifier is added during polymerization or (ii) in the presence of an fluorinated emulsifier selected from: [R f —O-L-COO-] i X i+ (I) wherein L represents a linear or branched, non-fluorinated, partially fluorinated, or fully fluorinated alkylene group, R f represents a linear or branched partially or fully fluorinated aliphatic group or a linear or branched partially or fully fluorinated aliphatic group interrupted with at least one oxygen atom, X i+ represents a cation having the valence i and i is 1, 2 or 3; wherein the reaction product and/or the resulting aqueous phase are substantially free of di- and tri-alkylamines and substantially free of low molecular weight fluoroorganic compounds and methods thereof.
1. A method of purifying a product comprising the following steps
(i) providing a fluoropolymer latex substantially free of a fluorinated emulsifier, wherein the fluoropolymer latex comprises at least 0.1% by weight solids and at least one low molecular weight fluoroorganic compound wherein the low molecular weight fluoroorganic compound is fluorinated and comprises a polar group and/or a reactive group;
(ii) contacting the fluoropolymer latex with a radical-forming process to degrade the at least one low molecular weight fluoroorganic compound into carbon dioxide, water, fluorine ions, and optionally cations; and
(iii) optionally, removing the fluorine ions and cations.
2. The method of claim 1 , wherein the low molecular weight fluoroorganic compound is an inert fluorinated liquid.
3. The method of claim 1 , wherein the radical forming process is an electrochemical process.
4. The method of claim 3 , wherein the electrochemical process comprises a hydroxy radical-generating electrode.
5. The method of claim 4 , wherein the hydroxy radical-generating electrode is selected from a boron doped diamond coated electrode, a lead oxide electrode, or a diamond particle electrode doped with boron.
6. The method of claim 5 , wherein the boron of the boron doped diamond coated electrode is doped at 0.05 ppm to 10000 ppm.
7. The method of claim 1 , wherein the potential used in the electrochemical process is 3 to 15 volts.
8. The method of claim 1 , further comprising removing the fluorine ions and cations, wherein the fluorine ions are removed via a precipitation process or an ion exchange process.
9. The method of claim 1 , wherein the low molecular weight fluoroorganic compound comprises a reactive group and the reactive group is selected from at least one of: an olefin, a halide, and an alkyl group comprising at least one of a bromine or iodine atom.
10. The method of claim 1 , wherein the fluoropolymer latex comprises at least 1% by weight solids.
11. The method of claim 1 , wherein the fluoropolymer latex comprises at least 10% by weight solids.
12. The method of claim 1 , wherein the polar group is selected from at least one of: an ether, an ester, and an acid.
13. A method of purifying a product comprising the following steps
(i) providing a fluoropolymer latex substantially free of a fluorinated emulsifier, wherein the fluoropolymer latex comprises at least 0.1% by weight solids and at least one low molecular weight fluoroorganic compound wherein the low molecular weight fluoroorganic compound is fluorinated and comprises a polar group and/or a reactive group;
(ii) contacting the fluoropolymer latex with a radical-forming process to degrade the at least one low molecular weight fluoroorganic compound into carbon dioxide, water, fluorine ions, and optionally cations; and
(iii) removing the fluorine ions and cations via a precipitation process or an ion exchange process.
14. The method of claim 13 , wherein the polar group is selected from at least one of: an ether, an ester, and an acid.
15. The method of claim 13 , wherein the low molecular weight fluoroorganic compound is an inert fluorinated liquid.
16. The method of claim 13 , wherein the radical forming process is an electrochemical process.
17. The method of claim 16 , wherein the electrochemical process comprises a hydroxy radical-generating electrode is selected from a boron doped diamond coated electrode, a lead oxide electrode, or a diamond particle electrode doped with boron.
18. The method of claim 13 , wherein the low molecular weight fluoroorganic compound comprises a reactive group and the reactive group is selected from at least one of: an olefin, a halide, and an alkyl group comprising at least one of a bromine or iodine atom.
19. The method of claim 13 , wherein the low molecular weight fluoroorganic compound is a fluorinated emulsifier.
20. The method of claim 13 , wherein the fluoropolymer latex comprises at least 1% by weight solids.