Method of sequestering metals using thiosulfate polymers
View Patent ↗A thiosulfate polymer composition includes an electron-accepting photosensitizer component, either as a separate compound or as an attachment to the thiosulfate polymer. The thiosulfate polymer composition can be applied to various articles, or used to form a predetermined polymeric pattern after photothermal reaction to form crosslinked disulfide bonds, removing non-crosslinked polymer, and reaction with a disulfide-reactive material. Such thiosulfate polymer compositions can also be used to sequestering metals.
1. A method of sequestering metal in a polymeric composition, the method comprising:
providing a polymeric layer comprising a non-crosslinked thiosulfate polymer that also comprises pendant organic charged groups,
photochemically reacting the non-crosslinked thiosulfate polymer to provide polymer layer areas comprising a crosslinked polymer having disulfide groups in a predetermined pattern in the polymeric layer, and polymeric layer areas outside the predetermined pattern comprising non-crosslinked thiosulfate polymer,
optionally washing the polymeric layer to remove the non-crosslinked thiosulfate polymer while leaving the crosslinked polymer in the predetermined pattern,
treating the polymeric layer with a metal ion solution to incorporate ions of a metal in the predetermined patterns comprising the crosslinked polymer having disulfide groups,
converting the incorporated metal ions to metal nanoparticles of the corresponding metal, and
electroless plating the metal nanoparticles to obtain a coating of the corresponding metal.
2. The method of claim 1 , wherein the polymeric layer further comprises an electron-accepting photosensitizer component.
3. The method of claim 1 , comprising treating the polymeric layer with silver, palladium, nickel, gold, or copper ions and reacting the silver, palladium, nickel, gold, or copper ions, to provide nanoparticles of the corresponding metal.
4. The method of claim 1 , wherein photochemically reacting of the non-crosslinked thiosulfate polymer is carried out in predetermined pattern through a mask using actinic radiation.
5. The method of claim 1 , wherein washing the polymeric layer to remove the non-crosslinked thiosulfate polymer is carried out using an aqueous solution.
6. The method of claim 1 , wherein the polymeric layer further comprises an electron-accepting photosensitizer component that is a covalently-connected component of the non-crosslinked thiosulfate polymer.
7. The method of claim 1 , wherein the non-crosslinked thiosulfate polymer is a copolymer comprising, in random order: (a) recurring units comprising thiosulfate groups, and (b) recurring units comprising an electron-accepting photo sensitizer component.
8. The method of claim 7 , wherein the copolymer further comprises, in random order, (c) recurring units other than the (a) and (b) recurring units, in an amount of at least 0.1 mol %, based on the total recurring units in the copolymer.
9. The method of claim 8 , wherein the (c) recurring units comprise a pendant carboxy, carboxylate, phospho, phosphonate, phosphate, sulfo, sulfonate, or sulfite group.
10. The method of claim 9 , wherein the copolymer further comprises (d) recurring units that have a total neutral charge and are present in an amount of at least 1 mol % and up to and including 49 mol %, based on the total recurring units in the copolymer.
11. The method of claim 10 , wherein the molar ratio of the (a) recurring units to the (d) recurring units in the copolymer is from 1:3 to 3:1.
12. The method of claim 1 , wherein the polymeric layer further comprises an electron-accepting photosensitizer component that is present in an amount of at least 0.1 mol % and up to and including 10 mol %, in relation to the molar amount of thiosulfate groups present in the polymeric layer.
13. The method of claim 1 , wherein the polymeric layer further comprises an electron-accepting photosensitizer component that is a compound separate from the non-crosslinked thiosulfate polymer.
14. The method of claim 1 , wherein the polymeric layer further comprises an electron-accepting photosensitizer component that is an organic photosensitizer N-containing heterocyclic compound.
15. The method of claim 1 , wherein the polymeric layer further comprises an electron-accepting photosensitizer component that is an inorganic salt or complex.
16. A method for sequestering metal ion in a polymeric composition, the method comprising:
providing a polymeric layer comprising a non-crosslinked thiosulfate polymer and a redox active metal ion,
photochemically reacting the non-crosslinked thiosulfate polymer to provide polymeric layer areas comprising a crosslinked polymer having disulfide groups in a predetermined pattern in the polymeric layer, and also to provide polymeric layer areas outside the predetermined pattern comprising non-crosslinked thiosulfate polymer,
optionally washing the polymeric layer to remove the non-crosslinked thiosulfate polymer in the polymeric layer areas outside the predetermined pattern,
contacting the polymeric layer with a metal ion solution to carry out a redox reaction and to incorporate metal nanoparticles on the areas comprising the crosslinked polymer, and
electroless plating the metal nanoparticles to obtain a predetermined pattern of the metal nanoparticles,
wherein the non-crosslinked thiosulfate polymer is a copolymer comprising, in random order: (a) recurring units comprising thiosulfate groups, (b) recurring units comprising an electron-accepting photosensitizer component, and (c) recurring units other than the (a) and (b) recurring units, in an amount of at least 0.1 mol %, based on the total recurring units in the copolymer, and the (c) recurring units comprise a pendant carboxy, carboxylate, phospho, phosphonate, phosphate, sulfo, sulfonate, or sulfite group.