PLA / PHA biodegradable coatings for seeds and fertilizers
AssigneeDanimer IPCo, LLC
InventorsJoe B. Grubbs, III, Jason John Locklin
Life of this patent
Estimating the term…
Abstract
A granular composition for agricultural is disclosed. The granular composition is made up of a plurality of granulates having a biodegradable coating applied over the granulates. The granulates are selected from the group consisting of seeds, fertilizers, and pesticides. The biodegradable coating is made up of polylactic acid and polyhydroxyalkanoates. A method for making the coated granular composition and a method for controlled release of the granular material in the field are also disclosed.
Claims24
A granular composition for agricultural use comprising:
- a plurality of granulates having a biodegradable coating applied over the granulates,
- wherein the granulates comprise a material selected from the group consisting of seeds, fertilizers, and pesticides, and
- wherein the biodegradable coating comprises from about 5 to about 75 weight percent polylactic acid and from about 25 to about 95 weight percent polyhydroxyalkanoates,
- wherein the biodegradable coating is annealed at 150-170° C. or exposed to solvent vapors after application to form a continuous phase of polylactic acid having globules of the polyhydroxyalkanoates homogeneously dispersed within the continuous phase, wherein the globules have an average size of from about 2 nm to about 10 micron.
A method for making a coated granular composition, comprising the steps of:
- mixing polylactic acid and a polyhydroxyalkanoate, optionally in the presence of a solvent, at a temperature from about 25° C. to about 180° C. to provide a coating mixture;
- applying the coating mixture over outer surfaces of a plurality of granulates comprising a material selected from the group consisting of seeds, fertilizers, and pesticides;
- solidifying the coating mixture to create a biodegradable coating over the outer surfaces of the plurality of granulates, and
- annealing the biodegradable coating in order to form a continuous phase of polylactic acid having globules of the polyhydroxyalkanoates homogeneously dispersed within the continuous phase, wherein the globules have an average size of from about 2 nm to about 10 micron, wherein the annealing comprises thermal annealing at 150-170° C. or solvent annealing by exposing the biodegradable coating to solvent vapors.
Dependencies are inferred from the claim text.