Microencapsulated nitrification inhibitor composition
View Patent ↗The present invention relates to an improved nitrification inhibitor composition and its use in agricultural applications.
1. A microcapsule suspension formulation, comprising:
(a) a suspended phase, the suspended phase including a plurality of microcapsules, the microcapsules having a volume median particle size of from about 1 to about 10 microns, wherein the microcapsules comprise:
(1) a microcapsule wall produced by an interfacial polycondensation reaction between a polymeric isocyanate and a polyamine to form a polyurea shell having a weight percentage of about 0.2 to about 40 percent of a total weight of the microcapsule suspension formulation, and
(2) a substantially liquid core, the substantially liquid core is encapsulated within the polyurea shell, wherein the substantially liquid core includes about 60 weight percent 2-chloro-6-(trichloromethyl)pyridine of the entire microcapsule and wherein at a temperature of at least 15° C. the substantially liquid core includes no more than 1.0 weight percent solid 2-chloro-6-(trichloromethyl)pyridine; and
(b) an aqueous phase, wherein the aqueous phase includes at least about 1.0 weight percent aromatic solvent of a total weight of the microcapsule suspension formulation.
2. The microcapsule suspension formulation according to claim 1 , further including:
at least one ionic stabilizer present in the aqueous phase.
3. The microcapsule suspension formulation according to claim 1 , wherein the aromatic solvent present in the aqueous phase is at least one compound selected from the group consisting of: light aromatics, naphthalene depleted light aromatics, heavy aromatics, and naphthalene depleted heavy aromatics.
4. The microcapsule suspension formulation according to claim 3 , wherein the aromatic solvent present in the aqueous phase is naphthalene depleted heavy C10-13aromatics.
5. The microcapsule suspension formulation according to claim 4 , wherein the aromatic solvent present in the aqueous phase comprises between about 1% by weight and about 10% by weight naphthalene depleted heavy C10-13 aromatics.
6. The microcapsule suspension formulation according to claim 4 , wherein the aromatic solvent present in the aqueous phase, comprises between about 2% by weight and about 5% by weight naphthalene depleted heavy C10-13 aromatics.
7. The microcapsule suspension formulation according to claim 4 , wherein the aromatic solvent present in the aqueous phase comprises between about 2.5% by weight and about 3.0% by weight naphthalene depleted heavy C10-13 aromatics.
8. The microcapsule suspension formulation according to claim 3 , wherein the aromatic solvent present in the aqueous phase is heavy C10-13 aromatics.
9. The microcapsule suspension formulation according to claim 8 , wherein the aromatic solvent present in the aqueous phase comprises between about 1% by weight and about 10% by weight heavy C10-13 aromatics.
10. The microcapsule suspension formulation according to claim 8 , wherein the aromatic solvent present in the aqueous phase comprises between about 2% by weight and about 5% by weight heavy C10-13 aromatics.
11. The microcapsule suspension formulation according to claim 8 , wherein the aromatic solvent present in the aqueous phase comprises between about 2.5% by weight and about 3.0% by weight heavy C10-13 aromatics.
12. The microcapsule suspension formulation according to claim 1 , wherein the microcapsules have a volume median particle size of from about 1 to about 5 microns.
13. The microcapsule suspension formulation according to claim 1 , wherein the ratio of the suspended phase a) to the aqueous phase b) is from about 1:0.75 to about 1:100.
14. The microcapsule suspension formulation according to claim 1 , wherein the ratio of the suspended phase a) to the aqueous phase b) is from about 1:1 to about 1:7.
15. The microcapsule suspension formulation according to claim 1 , wherein the ratio of the suspended phase a) to the aqueous phase b) is from about 1:1 to about 1:4.
16. The microcapsule suspension formulation according to claim 1 , wherein the polymeric isocyanate is polymethylene polyphenylisocyanate.
17. A fertilizer composition comprising: a nitrogen fertilizer and the microcapsule suspension formulation according to claim 1 .
18. The fertilizer composition according to claim 17 , wherein the nitrogen fertilizer is urea ammonium nitrate.
19. A method of suppressing the nitrification of ammonium nitrogen in growth medium comprising the steps of applying the microcapsule suspension formulation of claim 1 to a plant growth medium.
20. The method according to claim 19 , wherein the formulation is applied in combination with a pesticide or sequentially with a pesticide.