US4985064A
Expired / Lapsed
US
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Microsuspension process for preparing solvent core sequential polymer dispersion
Assignee: Rohm and Haas Co
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Filing: 1986-12-16
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Granted: 1991-01-15
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Expires: 2006-12-16
Abstract
Abstract The present invention relates to a sequential polymerization process for preparing a water-insoluble dispersion of core/shell particles. In one embodiment the process may be employed to produce a particulate dispersion useful in making water-based coating compositions wherein on drying the particulate dispersion serves as an opacifying agent. In another embodiment the process may be employed to microencapsulate a hydrophobic target material, such as a biocide or herbicide.
Inventors
- 👤 George H. Redlich
- 👤 Ronald W. Novak
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 09:38
CPC Classifications
C; C08; C08J; C08J3/00; C08J3/12; C08F; C08F2/00; C08F2/12; C08F2/16; C08F2/22; A; A01; A01N; A01N25/00; A01N25/26; A01N25/28; C08F285/00; C08F291/00; C08F8/00; C08F8/30; C08F8/32; C08F8/44; C08J3/126; C09; C09D; C09D5/00; C09D5/02; C09D5/024; C09D5/028; C09D7/00; C09D7/40; C09D7/45; C09D7/65; C09D7/70; C08J2333/00; C08J2333/04; C08J2333/06; C08J2333/10; C08J2333/12; Y; Y10; Y10S; Y10S525/00; Y10S525/902; Y10S525/911; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982; Y10T428/2984; Y10T428/2985; Y10T428/2987; Y10T428/2989; Y10T428/2991; Y10T428/2998
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
155 words
A process for encapsulating at least one organic target material in water-insoluble core/shell particles comprising (a) preparing core emulsion by emulsifying in water at high shear constituents comprising (1) organic target material to be encapsulated, (2) at least one hydrophilic solvent, (3) initial monomer comprising at least two polymerizable mono-alpha, beta-ethylenically unsaturated compounds wherein said initial monomer includes from about 2 to 4 percent by weight, based on total weight of said initial monomer, of alpha, beta-ethylenically unsaturated carboxylic acid monomer, (4) hydrophobic anionic surfactant, (5) water-insoluble emulsion stabilizer, (6) water-insoluble thermal polymerization initiator, and wherein said organic target material and hydrophilic solvents are non-solvents for polymer prepared by polymerizing said initial monomer, (b) heating said core emulsion to polymerize said initial monomer thereby forming core particles, and (c) adding at least one base selected from the group consisting of ammonia and the non-nucleophilic organic amines thereby neutralizing polymerized carboxylic acid and forming core/shell particles.
Claim 2
Dependent Claim
155 words
A process for encapsulating at least one organic target material in water-insoluble core/shell particles comprising (a) preparing core emulsion by emulsifying in water at high shear constituents comprising (1) organic target material to be encapsulated, (2) at least one hydrophilic solvent, (3) initial monomer comprising at least two polymerizable mono-alpha, beta-ethylenically unsaturated compounds wherein said initial monomer includes from about 2 to 4 percent by weight, based on total weight of said initial monomer, of alpha, beta-ethylenically unsaturated carboxylic acid monomer, (4) hydrophobic anionic surfactant, (5) water-insoluble emulsion stabilizer, (6) water-insoluble thermal polymerization initiator, and wherein said organic target material and hydrophilic solvents are non-solvents for polymer prepared by polymerizing said initial monomer, (b) heating said core emulsion to polymerize said initial monomer thereby forming core particles, and (c) adding at least one base selected from the group consisting of ammonia and the non-nucleophilic organic amines thereby neutralizing polymerized carboxylic acid and forming core/shell particles.
Claim 3
Dependent Claim
33 words
The process of claim 1 wherein said core emulsion is prepared from constituents additionally comprising at least one hydrophobic solvent which is a non-solvent for the polymer prepared by polymerizing said initial monomer.
Claim 4
Dependent Claim
20 words
The process of claim 2 additionally comprising adding additional monomer whereby said additional monomer is polymerized on the core/shell particles.
Claim 5
Dependent Claim
26 words
The process of claim 48 wherein the additional monomer is selected to yield a polymer having a calculated glass transition temperature greater than about 70° C.
Claim 6
Dependent Claim
16 words
The process of claim 4 wherein aid additional monomer comprises at least one multi-alpha,beta-ethylenically unsaturated monomer.
Claim 7
Dependent Claim
24 words
The process of claim 5 wherein said multi-alpha, beta-ethylenically unsaturated monomer comprises no more than about 5 percent by weight of said additional monomer.
Claim 8
Dependent Claim
27 words
The process of claim 4 wherein said additional monomer comprises at least 80% by weight, based on the total weight of said additional monomer, of methyl methacrylate.
Claim 9
Dependent Claim
25 words
The process of claim 2 wherein the initial monomer is selected to yield polymer having a calculated glass transition temperature greater than about 70° C.
Claim 10
Dependent Claim
38 words
The process of claim 8 wherein the initial monomer comprises at least 80% by weight, based on the total weight of said initial monomer, of monomer selected from the group consisting of methyl methacrylate, styrene, and mixtures thereof.
Claim 11
Dependent Claim
63 words
The process of claim 9 wherein the hydrophobic solvent is selected from the group consisting of the acyclic paraffinic hydrocarbons, mixtures of the acyclic paraffinic hydrocarbons and cyclic paraffinic hydrocarbons, and mixtures of acyclic paraffinic hydrocarbons, cyclic paraffinic hydrocarbons and aromatic hydrocarbons wherein said mixtures contain less than about 10% by weight, based on the total weight of the mixture, of aromatic hydrocarbon.
Claim 12
Dependent Claim
29 words
The process of claim 10 wherein the hydrophilic solvent is selected from the group consisting of the isomers of butanol, pentanol, hexanol, and methyl isobutyl carbinol, and mixtures thereof.
Claim 13
Dependent Claim
22 words
The process of claim 11 wherein the 50% distillation temperature of said hydrophobic solvent is from about 150° C. to 200° C.
Claim 14
Dependent Claim
42 words
The process of claim 2 wherein said initial monomer comprises up to about 10 percent by weight, based on the total weight of said initial monomer, of nonionizable monomer selected from the group consisting of ethyl acrylate and acrylonitrile and mixtures thereof.
Claim 15
Dependent Claim
12 words
The process of claim 13 wherein said nonionizable monomer is ethyl acrylate.
Claim 16
Dependent Claim
39 words
The process of claim 2 wherein the anionic surfactant is selected from the group consisting of the alkali metal salts of the di(C 7 c 25 )alkyl sulfosuccinates and the alkyl aryl polyalkoxy sulfonates and alkyl aryl polyalkoxy phosphates.
Claim 17
Dependent Claim
28 words
The process of claim 15 wherein the anionic surfactant is selected from the group consisting of the alkali metal salts of dioctyl sulfosuccinate and of dodecyl benzene sulfonate.
Claim 18
Dependent Claim
34 words
The process of claim 2 wherein the water-insoluble emulsion stabilizer is an organic compound having a molecular weight of less than about 500 and a water solubility of less than about 10 -4 g/l.
Claim 19
Dependent Claim
57 words
The process of claim 17 wherein said water-insoluble emulsion stabilizer is selected from the group consisting of di(C 4 -C 10 )alkyl phthalates, dibutoxyethyl phthalate, n-butyl benzyl phthalate, dimethyl cyclohexyl phthalate, dicyclohexyl phthalate, diphenyl phthalate, dipropylene glycol dibenzoate, diethylene glycol dibenzoate, triethylene glycol di(2-ethyl butyrate), di(2-ethylhexyl)adipate, di-isooctyl azelate, di-(2-ethylhexyl) azelate, di-n-butyl sebacate, 1-chlorododecane, hexadecane, and mixtures thereof.
Claim 20
Dependent Claim
26 words
The process of claim 17 wherein said water-insoluble emulsion stabilizer comprises at least about 0.25 percent by weight of the organic phase of the core emulsion.
Claim 21
Dependent Claim
29 words
The process of claim 2 wherein the ratio of the weight of water-insoluble thermal polymerization initiator to the total weight of initial monomer is from about 0.1:100 to 5:100.
Claim 22
Dependent Claim
30 words
The process of claim 20 wherein the ratio of the weight of said water-insoluble thermal polymerization initiator to the total weight of initial monomer is from abut 2.5:100 to 4.0:100.
Claim 23
Dependent Claim
14 words
The process of claim 20 wherein said water-insoluble thermal polymerization initiator is lauryl peroxide.
Claim 24
Dependent Claim
21 words
The process of claim 2 wherein the hydrophobic organic target compound to be encapsulated has at least one isocyanate functional group.
Claim 25
Dependent Claim
19 words
The process of claim 2 wherein said organic target compound to be encapsulated has at least one epoxy group.
Claim 26
Dependent Claim
16 words
The process of claim 1 wherein the organic target material to be encapsulated has biocidal activity.
Claim 27
Dependent Claim
20 words
An encapsulated biocide comprising an aqueous dispersion of the water-insoluble core/shell particles prepared according to the process of claim 25.
Claim 28
Dependent Claim
22 words
The process of claim 1 wherein the organic target material is selected from the group consisting of 2-n-octyl-3-isothiazolone, oxyfluorfen and mixtures thereof.
Claim 29
Dependent Claim
13 words
The process of claim 27 wherein said hydrophobic organic target compound is oxyfluorfen.
Claim 30
Dependent Claim
21 words
A coating composition comprising core/shell particles produced according to the process of claim 27 pigments, extenders and vinyl addition latex polymer.
Claim 31
Dependent Claim
18 words
A sprayable agricultural herbicide composition comprising herbicidally effective target material encapsulated according to the process of claim 1.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1994-01-14 | 1994-07-16 | 1995-01-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-01-14 | 1998-07-16 | 1999-01-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-01-14 | 2002-07-16 | 2003-01-15 | $7700.00 | Window Closed / Lapsed |