Microcapsule comprising a polyester-urethane shell and a hydrophobic core material

Patent metadata

Field	Value
Publication number	US-11077417-B2
Application number	US-201615778305-A
Country	US
Kind code	B2
Filing date	Nov 8, 2016
Priority date	Nov 23, 2015
Publication date	Aug 3, 2021
Grant date	Aug 3, 2021

Abstract

Disclosed herein are microcapsules as core-shell-particles, including a polymeric shell, a method of making them, a dispersion of those microcapsules in a liquid medium and use thereof. The microcapsules include a core that contains a hydrophobic component.

First claim

The invention claimed is:

1. A microcapsule comprising a capsule core and a polymeric shell, wherein the core comprises only hydrophobic components and the shell comprises in polymerized form:
A) at least one poly(ester-urethane) comprising at least 2 isocyanate groups, obtainable by reacting at least one polyester-polyol comprising at least 2 OH groups with at least one polyisocyanate comprising at least 2 NCO groups, and;
B1) at least one polymeric polyamine selected from the group consisting of polyaminosaccharides, polyamidoamines, polyesteramines, polyaminoacids and combinations thereof, having an average molecular weight of between about 375 g/mol and about 2500 g/mol, and comprising at least 3 amino groups reactive towards NCO groups.

2. The microcapsule according to claim 1 , wherein the poly(ester-urethane) is a reaction product of the polyester-polyol with the polyisocyanate which is selected from the group consisting of hexamethylene diisocyanate, tetramethylene diisocyanate, dicyclohexylmethane-4,4′-diisocyanate, isophoronediisocyanate, 2,4- and 2,6-toluylene diisocyanate and isomer mixtures thereof, 2,4′- and 4,4′-diphenylmethane diisocyanate and isomer mixtures, biurets, allophanates and/or isocyanurates or mixtures thereof.

3. The microcapsule according to claim 1 , wherein the polyester-polyol is a polylactonepolyol which comprises 2 or 3 OH groups.

4. The microcapsule according to claim 1 , wherein the polyester-polyol is a compound of the formulae (2), (5), or mixtures thereof

wherein
R a is selected from linear or branched C 1 -C 10 -alkylene group and C 3 -C 20 -cycloaliphatic radicals having 3 to 10 ring carbon atoms,
R b is a linear or branched C 1 -C 10 -alkantriyl group,
l, m and n are independently an integer of 1 to 100,
with the proviso that
in the formula (2) n+m is an integer of 2 to 100,
in the formula (5) n+m+1 is an integer of 2 to 100.

5. The microcapsule according to claim 1 , wherein the polyester-polyol has a weight-average molecular weight of from 200 to 3000 g/mol.

6. The microcapsule according to claim 1 , wherein the shell comprises in polymerized form a component B1) which comprises at least one polyamidoamine.

7. The microcapsule according to claim 6 , wherein the at least one polyamidoamine is polylysine and wherein the polylysine has an average molecular weight of 375 to 2500 g/mol.

8. The microcapsule according to claim 1 , wherein a core-shell ratio (w/w) of the microcapsule is 20:1 to 1:1.

9. The microcapsule according to claim 1 , wherein a mean particle size of the microcapsule d(0.5) is in the range from 0.5 μm to 50 μm.

10. The microcapsule according to claim 1 , wherein the hydrophobic components comprise a pesticide.

11. The microcapsule according to claim 1 , wherein the hydrophobic components comprise a pesticide and an oil body selected from the group consisting of vegetable oils, modified vegetable oils, synthetic (tri)glycerides, fatty acid alkyl esters, fatty acid alkyl esters based on C6-C22 fatty acids, mineral oils, hydrocarbons, saturated or unsaturated C6-C30-fatty acids, aromatic compounds, esters of linear C6-C22-fatty acids and mixtures thereof.

12. A microcapsule dispersion comprising at least one microcapsule according to claim 1 .

13. A process for the preparation of the microcapsule according to claim 1 , wherein the capsule core is obtainable by
a) providing a premix (Ib) comprising the hydrophobic component(s) to be encapsulated (Cb), and at least one component (A) as defined in claim 1 , and
b) mixing the premix (Ib) provided in step a) with a hydrophilic medium comprising at least one hydrophilic protective colloid, at least one component (B1) as defined in claim 1 , and reacting a resulting mixture to form microcapsules dispersed in the hydrophilic medium.

14. A method of controlling phytopathogenic fungi and/or undesired plant growth and/or undesired insect or mite attack and/or for regulating the growth of plants, wherein the microcapsule according to claim 1 , where the hydrophobic components comprise a pesticide, is allowed to act on the respective pests, their environment or the crop plants to be protected from the respective pest, on the soil and/or on undesired plants and/or on the crop plants and/or on their environment.

15. The microcapsule according to claim 8 , wherein the core-shell ratio (w/w) of the microcapsule is 10:1 to 2:1.

16. The microcapsule according to claim 15 , wherein the core-shell ratio (w/w) of the microcapsule is 6:1 to 3:1.

17. The microcapsule according to claim 9 , wherein the mean particle size of the microcapsule d(0.5) is in the range from 0.7 μm to 30 μm.

18. The microcapsule according to claim 10 , wherein the hydrophobic components further comprise an oil body.

19. The process according to claim 13 , wherein said providing a premix comprises providing the premix further comprising a hydrophobic medium that is liquid at 20° C. and 1023 mbar different from the (Cb).

20. The microcapsule according to claim 1 , wherein the microcapsule further comprises
B2) at least one compound different from B1) which comprises at least 2 terminal groups which are reactive towards isocyanate-groups and which are selected from OH, NHR, or SH, wherein R is selected from the group consisting of hydrogen, alkyl, cycloalkyl, and aryl.

Assignees

• Basf Se

Inventors

• Fuchs Yannick
• Witteler Helmut
• Bratz Matthias

Classifications

• A01N25/28 Primary

  Microcapsules {or nanocapsules} · CPC title

• A61K9/5089

  Processes · CPC title

• A61K8/87

  Polyurethanes · CPC title

• A61K8/11

  Encapsulated compositions · CPC title

• A61K9/5031

  obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds, e.g. polyethylene glycol, poly(lactide-co-glycolide) · CPC title