US4515914A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Crosslinked latexes encapsulated with linear polymers
Assignee: Dow Chemical Co
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Filing: 1983-10-19
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Granted: 1985-05-07
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Expires: 2003-10-19
Abstract
Abstract Highly coalescence-capable and deformable latexes have a controlled crosslinking density. For example, a styrene/butadiene core is prepared using conventional emulsion polymerization techniques and at a point at which much of the butadiene is converted to polymer a second stage monomer mixture comprising monovinyl monomers is contacted with the initial mixture to yield a latex having a shell region comprising essentially linear polymers which are partially covalently bonded to said core region.
Inventors
- 👤 Michio Tsurumi
- 👤 Do I. Lee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 06:12
CPC Classifications
C; C08; C08F; C08F279/00; C08F279/02; C08F257/00; C09; C09D; C09D151/00; C09D151/04
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
159 words
A process for preparing coalescence-capable and deformable aqueous polymer latexes having controlled crosslinking density wherein the dispersed polymer particles are heterogeneous, which process comprises: (a) preparing by emulsion polymerization a core domain comprising the polymerization product of a portion of a first stage monomer mixture comprising at least one monovinyl aromatic monomer and at least one open chain conjugated diene monomer and (b) contacting said first stage monomer mixture at a point at which said mixture is partially polymerized with a second stage monomer mixture comprising at least one monovinyl monomer and substantially noncrosslinkable monomers wherein said second stage monomer mixture is introduced when the rate of conversion of monomer to polymer is such that (1) the latex particles so formed are not highly crosslinked, and (2) the second stage monomer mixture is polymerized to yield essentially noncrosslinked linear polymers to encapsulate the core domain as a shell and is partially covalently bonded to the partially polymerized core domain.
Claim 2
Dependent Claim
159 words
A process for preparing coalescence-capable and deformable aqueous polymer latexes having controlled crosslinking density wherein the dispersed polymer particles are heterogeneous, which process comprises: (a) preparing by emulsion polymerization a core domain comprising the polymerization product of a portion of a first stage monomer mixture comprising at least one monovinyl aromatic monomer and at least one open chain conjugated diene monomer and (b) contacting said first stage monomer mixture at a point at which said mixture is partially polymerized with a second stage monomer mixture comprising at least one monovinyl monomer and substantially noncrosslinkable monomers wherein said second stage monomer mixture is introduced when the rate of conversion of monomer to polymer is such that (1) the latex particles so formed are not highly crosslinked, and (2) the second stage monomer mixture is polymerized to yield essentially noncrosslinked linear polymers to encapsulate the core domain as a shell and is partially covalently bonded to the partially polymerized core domain.
Claim 3
Dependent Claim
35 words
A process of claim 1 comprising from about 60 to about 90 weight parts of said first stage monomer mixture and from about 10 to about 40 weight parts of said second stage monomer mixture.
Claim 4
Dependent Claim
39 words
A process of claim 1 wherein said second stage monomer mixture is contacted with said first stage monomer mixture at a point at which about 60 to about 90 weight percent of said diene monomer is converted to polymer.
Claim 5
Dependent Claim
36 words
A process of claim 1 wherein said first stage monomer mixture comprises from about 30 to about 70 weight percent monovinyl aromatic monomer and from about 30 to about 70 weight percent of said diene monomer.
Claim 6
Dependent Claim
39 words
A process of claim 1 wherein said second stage monomer mixture comprises from about 30 to about 100 weight percent monovinyl aromatic monomer and from about 0 to about 70 weight percent of at least one other monovinyl monomer.
Claim 7
Dependent Claim
18 words
A coalescence-capable and deformable latex having controlled crosslinking density which is prepared using the process of claim 1.
Claim 8
Dependent Claim
17 words
A latex of claim 6 having an average diameter of from about 0.1 to about 0.3 micrometer.
Claim 9
Dependent Claim
16 words
A latex of claim 6 comprising a styrene/butadiene core domain and a styrene/n-butyl actylate shell domain.
Claim 10
Dependent Claim
21 words
The process of claim 1 wherein said second stage monomer mixture consists of monovinyl monomers or other noncrosslinkable monomers or agents.
References Cited (Backward Citations)
US3256233A
Cited
US3296176A
Cited
US3804881A
Cited
US3970725A
Cited
US4187202A
Cited
US4150005A
Cited
JPS54131013A
Cited
US4156669A
Cited
JPS54151606A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-05-06 | 1988-11-05 | 1989-05-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-05-06 | 1992-11-05 | 1993-05-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-05-06 | 1996-11-05 | 1997-05-07 | $7700.00 | Window Closed / Lapsed |