Biodegradable delivery particles
A biodegradable delivery particle having a benefit agent containing core and a shell.
1 . A delivery particle comprising a core and a wall encapsulating said core, wherein:
the core comprises a benefit agent and a partitioning modifier;
the wall is formed by a radical polymerization reaction between:
a) a water soluble hydroxyl containing linear carbon-chain polymer comprising 1,2-diol and/or 1,3-diol functionality;
b) a multifunctional (meth)acrylate monomer and/or oligomer;
c) optionally, a mono- and/or di-functional monomer and/or oligomer;
d) at least one water soluble thermal free radical initiator;
e) at least one oil soluble thermal free radical initiator;
wherein at least one of the water-soluble initiators is a persulfate and the water soluble hydroxyl containing linear carbon-chain polymer forms carbon/carbon and/or oxygen/carbon bonds with the multifunctional (meth)acrylate monomer and/or oligomer.
2 . The delivery particle of claim 1 , wherein the benefit agent is a fragrance.
3 . The delivery particle of claim 1 , wherein the partitioning modifier is selected from the group consisting of isopropyl myristate, vegetable oil, modified vegetable oil, mono-, di-, and tri-esters of C4-C24 fatty acids, dodecanophenone, lauryl laurate, methyl behenate, methyl laurate, methyl palmitate, methyl stearate, and mixtures thereof.
4 . The delivery particle of claim 1 , wherein the water soluble hydroxyl containing polymer has a degree of hydrolysis from about 55% to about 99%.
5 . The delivery particle of claim 1 , wherein the water soluble hydroxyl containing linear carbon-chain polymer is partially acetylated.
6 . The delivery particle of claim 1 , wherein the wall further comprises a polysaccharide.
7 . The delivery particle of claim 6 , wherein the polysaccharide has at least one amine moiety.
8 . The delivery particle of claim 6 , wherein the polysaccharide is selected from the group consisting of pectin, carrageenan, cellulose, chitosan, chitin, xanthan gum, tara gum, konjac gum, alginate, hyaluronic acid, amylase, lignin, diutan gum, and mixtures thereof.
9 . The delivery particle of claim 1 , wherein the water soluble hydroxyl containing linear carbon-chain polymer is at least 20 weight percentage of the total wall.
10 . The delivery particle of claim 1 , wherein the polysaccharide is at least 2% weight percentage of the total wall.
11 . The delivery particle of claim 1 , wherein the water soluble hydroxyl containing linear carbon-chain polymer and/or the polysaccharide has a molecular weight from about 30 kDa to about 500 kDa.
12 . The delivery particle of claim 1 , wherein the water soluble hydroxyl containing linear carbon-chain polymer and/or polysaccharide has a biodegradability above 30% CO 2 in 60 days following OECD 301B test.
13 . The delivery particle of claim 1 , wherein the multifunctional (meth)acrylate monomer and/or oligomer is selected from group consisting of tri-functional (meth)acrylate, tetra-functional (meth)acrylate, penta-functional (meth)acrylate, hexa-functional (meth)acrylate, hepta-functional (meth)acrylate, and mixtures thereof.
14 . The delivery particle of claim 1 , wherein the multifunctional (meth)acrylate monomers and/or oligomer comprises a hexafunctional aromatic urethane acrylate.
15 . The delivery particle of claim 1 , wherein the multifunctional (meth)acrylate monomer and/or oligomer comprises a multifunctional aliphatic urethane acrylate.
16 . The delivery particle of claim 1 , wherein the multifunctional (meth)acrylate monomer and/or oligomer is at least 5%.
17 . The delivery particle of claim 1 , wherein the mono- and/or di-functional monomer and/or oligomer are independently selected from the group consisting of:
wherein
R1, R2, RS, R6, R7, R8, R9 and RIO are independently selected from the group consisting of a hydrogen (*—H) and a methyl group (*—CH3);
a, b, c and dare integers independently selected from 1 to 10,
R3 and R4 are independently selected from the group consisting of
h and i are integers independently selected from 0 to 10;
R 11 is selected from the group consisting of hydroxyl (*—OH), hydrogen (*—H), and methyl group (*—CH 3 ).
18 . The delivery particle of claim 1 , wherein the water soluble thermal free radical initiator is selected from the group consisting of ammonium persulfate, potassium persulfate, sodium persulfate and mixtures thereof.
19 . The delivery particle of claim 1 , wherein the oil soluble thermal free radical initiator is an azo-based initiator.
20 . The delivery particle of claim 15 , wherein the azo-based initiator is selected from the group consisting of 2,2′-azobis(isobutylnitrile), 2,2′-azobis(2,4-dimethylpentanenitrile), 2,2′-azobis(2,4-dimethylvaleronitrile), 2,2′-azobis(2-methylpropanenitrile), 2,2′-azobis(2-methylbutyronitrile), 1,1′-azobis (cyclohexanecarbonitrile), 1,1′-azobis(cyanocyclohexane) and mixtures thereof.
21 . The delivery particle of claim 1 , wherein the water soluble hydroxyl containing polymer and/or polysaccharide is fragmented by the water soluble initiator prior to form carbon/carbon, oxygen/carbon, and/or nitrogen/carbon bonds with the multifunctional (meth)acrylate monomer and/or oligomer.
22 . The delivery particle of claim 1 , wherein the water soluble hydroxyl containing polymer and/or polysaccharide forms carbon/carbon bonds with the multifunctional (meth)acrylate monomer and/or oligomer.
23 . The delivery particle of claim 1 , wherein the delivery particle is prepared at a pH from about 3 to about 7.
24 . The delivery particle of claim 1 , wherein the wall has a biodegradability above 30% CO 2 in 60 days following OECD 301B test.
25 . The delivery particle according to claim 1 , wherein the wall of the delivery particles further comprises a coating material selected from the group consisting of poly(meth)acrylate, poly(ethylene-maleic anhydride), polyamine, wax, polyvinylpyrrolidone, polyvinylpyrrolidone co-polymers, polyvinylpyrrolidone-ethy-acrylate, polyvinylpyrrolidone-vinyl acrylate, polyvinylpyrrolidone methacrylate, polyvinylpyrrolidone/vinyl acetate, polyvinyl acetal, polyvinyl butyral, polysiloxane, poly(propylene maleic anhydride), maleic anhydride derivatives, co-polymers of maleic anhydride derivatives, polyvinyl alcohol, styrene-butadiene latex, gelatine, gum arabic, carboxymethyl cellulose, carboxymethyl hydroxyethyl cellulose, hydroxyethyl cellulose, other modified celluloses, sodium alginate, chitosan, chitin, casein, pectin, modified starch, polyvinyl acetal, polyvinyl butyral, polyvinyl methyl ether/maleic anhydride, polyvinyl pyrrolidone and its CO polymers, poly(vinyl pyrrolidone/methacrylamidopropyl trimethyl ammonium chloride), polyvinylpyrrolidone/vinyl acetate, polyvinyl pyrrolidone/dimethylaminoethyl methacrylate, polyvinyl amines, polyvinyl formamides, polyallyl amines, copolymers of polyvinyl amines, and mixtures thereof.
26 . An article of manufacture incorporating the microcapsules according to claim 1 .
27 . The article of manufacture according to claim 26 , wherein the article is selected from the group consisting of an agricultural formulation, a slurry encapsulating an agricultural active, a population of dry microcapsules encapsulating an agricultural active, an agricultural formulation encapsulating an insecticide, and an agricultural formulation for delivering a preemergent herbicide.
28 . The article of manufacture according to claim 27 wherein the agricultural active is selected from the group consisting of an agricultural herbicide, an agricultural pheromone, an agricultural pesticide, an agricultural nutrient, an insect control agent and a plant stimulant.