IODINE REVERSE TRANSFER POLYMERIZATION METHOD AND COMPOSITIONS THEREOF

Abstract

The reverse iodine transfer polymerization of an ethylenically unsaturated monomer comprising (meth)acrylic acid, a salt thereof, or a combination thereof, in the presence of a radical polymerization initiator, an oxidant, an iodide salt, and a solvent, is a useful method for manufacturing (meth)acrylic acid polymers. The amounts of components used can range from 5 to 500 equivalents of the ethylenically unsaturated monomer comprising (meth)acrylic acid, a salt thereof, or a combination thereof, in the presence of 1 to 3 equivalents of the radical polymerization initiator, 0.2 to 1 equivalent of the oxidant, and 1 equivalent of the iodide salt. (Meth)acrylic acid polymer solutions are prepared by these methods. (Meth)acrylic polymers are useful as dispersants.

Claims

Having described the invention as above, the following claims are claimed as property:

1. A method for preparing a (meth)acrylic acid polymer, characterized in that it comprises the reverse iodine transfer polymerization of an ethylenically unsaturated monomer comprising (meth)acrylic acid, a salt thereof or a combination thereof, in the presence of: a radical polymerization initiator generating carbon-centered radicals; an oxidant; an iodide salt; and a solvent.

2. The method according to claim 1, characterized in that the ethylenically unsaturated monomer comprises a combination of (meth)acrylic acid and a salt thereof.

3. The method according to claim 1 or 2, characterized in that the acrylic (met) salt and the iodide salt are each, independently, an alkali metal salt, an alkaline earth metal salt, an ammonium salt, a quaternary ammonium salt or a combination comprising at least one of the above salts.

4. The method according to any of claims 1 to 3, characterized in that the ethylenically unsaturated monomer further comprises one or more other (meth)acrylic or vinyl monomers.

5. The method according to any of claims 1 to 4, characterized in that the solvent is an aqueous solvent comprising 50 to 100 percent by volume of water, based on the total volume of the solvent.

6. The method according to any of claims 1 to 5, characterized in that the radical polymerization initiator is an azo polymerization initiator.

7. The method according to any of claims 1 to 6, characterized in that the oxidant is a peroxide.

8. The method according to any of claims 1 to 7, characterized in that the polymerization is carried out from 0 to 140 °C for 1 minute to 48 hours.

9. The method according to any of claims 1 to 8, characterized in that the solvent comprises water, and the ethylenically unsaturated monomer is present as a 10 to 90 percent by volume solution in the solvent, based on the total volume of the ethylenically unsaturated monomer and solvent.

10. The method according to any of claims 1 to 9, characterized in that it comprises the reverse iodine transfer polymerization of 5 to 500 equivalents of the ethylenically unsaturated monomer comprising (meth)acrylic acid, a salt thereof or a combination thereof, in the presence of 1 to 3 equivalents of the radical polymerization initiator, 0.2 to 1 equivalent of the oxidant and 1 equivalent of the iodide salt.

11. The method according to any of claims 1 to 10, characterized in that it comprises the reverse iodine transfer polymerization of 2.5 to 250 equivalents of (meth)acrylic acid and 2.5 to 250 equivalents of a (meth)acrylic acid salt, in the presence of 1 to 3 equivalents of the radical polymerization initiator, 0.2 to 1 equivalent of the oxidant, and 1 equivalent of the iodide salt.

12. The method according to any of claims 1 to 11, characterized in that the (meth)acrylic polymer or copolymer is predominantly linear and has a molar mass (Mn) of 1 to 100 kg / mol and a dispersion of 1 to 5, as measured by chloroform size exclusion chromatography against polystyrene standards after trimethylsilyl diazomethane methylation.

13. A method for manufacturing a (meth)acrylic polymer or copolymer, characterized in that it comprises the reverse iodine transfer polymerization of 2.5 to 250 equivalents of acrylic acid and 2.5 to 250 equivalents of sodium acrylate, both dissolved in water to form a 40 to 60 percent by volume solution, based on the total volume of acrylic acid, sodium acrylate and water, in the presence of: 1 to 2 equivalents of an azo polymerization initiator; 0.4 to 1 equivalent of a persulfate; and 1 equivalent of an alkali metal iodide.

14. A (meth)acrylic polymer or copolymer solution characterized in that it is prepared by the method according to any one of claims 1 to 11, wherein the (meth)acrylic polymer or copolymer has less than or equal to 5% branching, calculated from 13C-NMR data as described in the Examples section in Materials and Methods, and has a molar mass (Mn) of 1 to 100 kg / mol and a dispersion (D) of 1 to 5, measured by chloroform size exclusion chromatography against polystyrene standards after trimethylsilyl diazomethane methylation.

15. The (meth)acrylic polymer or copolymer solution according to claim 14, characterized in that it comprises an aqueous solution of 10 to 90 percent by volume of the (meth)acrylic polymer or copolymer, based on the total volume of the (meth)acrylic polymer or copolymer and water.

16. The (meth)acrylic polymer or copolymer solution according to claim 14 or 15, prepared by reverse iodine transfer polymerization of 5 to 500 equivalents of the ethylenically unsaturated monomer, characterized in that it comprises (meth)acrylic acid, a salt thereof or a combination thereof, in the presence of 1 to 3 equivalents of the azo polymerization initiator, 0.2 to 1 equivalent of the oxidant and 1 equivalent of the iodide salt.

17. The (meth)acrylic polymer or copolymer solution according to any of claims 14 to 16, characterized in that it is prepared by copolymerization of 2.5 to 250 equivalents of acrylic acid and 2.5 to 250 equivalents of sodium acrylate.