US4200708A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for sequentially dispersing and saponifying ethylene-vinyl acetate copolymer
Assignee: Millennium Petrochemicals Inc
•
Filing: 1978-08-17
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Granted: 1980-04-29
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Expires: 1998-08-17
Abstract
Abstract Finely divided saponified ethylene-vinyl acetate copolymer particles are prepared by forming an aqueous dispersion of the copolymer without effecting any appreciable saponification of the dispersed copolymer and thereafter saponifying the dispersed copolymer to the extent desired.
Inventors
- 👤 Dorothee M. McClain
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 00:53
CPC Classifications
C; C08; C08F; C08F8/00; C08F8/12; C08F2810/00; C08F2810/50
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
99 words
A process for obtaining finely divided saponified ethylene-vinyl acetate copolymer particles which comprises the sequential steps of: (a) dispersing the copolymer in an aqueous dispersion medium containing a dispersing agent for EVA copolymer under such conditions of time and/or temperature that no appreciable saponification of the dispersed copolymer can occur, the resulting dispersion being made up of particles of an average diameter of from about 20 to about 500 microns; and, (b) saponifying the dispersed copolymer employing a strong base as the saponifying agent under such conditions of time and/or temperature that saponification to a predetermined extent is achieved.
Claim 2
Dependent Claim
99 words
A process for obtaining finely divided saponified ethylene-vinyl acetate copolymer particles which comprises the sequential steps of: (a) dispersing the copolymer in an aqueous dispersion medium containing a dispersing agent for EVA copolymer under such conditions of time and/or temperature that no appreciable saponification of the dispersed copolymer can occur, the resulting dispersion being made up of particles of an average diameter of from about 20 to about 500 microns; and, (b) saponifying the dispersed copolymer employing a strong base as the saponifying agent under such conditions of time and/or temperature that saponification to a predetermined extent is achieved.
Claim 3
Dependent Claim
21 words
The process of claim 1 wherein the ethylene-vinyl acetate copolymer contains up to about 15% by weight of combined vinyl acetate.
Claim 4
Dependent Claim
25 words
The process of claim 1 wherein the ethylene-vinyl acetate copolymer contains from above about 15% up to about 35% by weight of combined vinyl acetate.
Claim 5
Dependent Claim
20 words
The process of claim 1 wherein the ethylene-vinyl acetate copolymer contains above about 35% by weight of combined vinyl acetate.
Claim 6
Dependent Claim
33 words
The process of claim 2 wherein the dispersing agent is a combination of a soap of an alkali metal having an atomic weight of at least 23 and a water-soluble substantially neutral salt.
Claim 7
Dependent Claim
33 words
The process of claim 3 wherein the dispersing agent is a combination of a soap of an alkali metal having an atomic weight of at least 23 and a water-soluble substantially neutral salt.
Claim 8
Dependent Claim
24 words
The process of claim 4 wherein the dispersing agent is a soap of an alkali metal having an atomic weight of at least 23.
Claim 9
Dependent Claim
17 words
The process of claim 5 wherein the soap is sodium stearate and the salt is sodium chloride.
Claim 10
Dependent Claim
17 words
The process of claim 6 wherein the soap is sodium stearate and the salt is sodium chloride.
Claim 11
Dependent Claim
11 words
The process of claim 7 wherein the soap is sodium stearate.
Claim 12
Dependent Claim
19 words
The process of claim 1 wherein the dispersing agent is a lithium soap of a higher saturated fatty acid.
Claim 13
Dependent Claim
11 words
The process of claim 11 wherein the soap is lithium behenate.
Claim 14
Dependent Claim
65 words
The process of claim 1 wherein the dispersing agent is selected from the group of surface active agents consisting of the sulfates, sulfonates, sarcosinates, and sodium salts of organophosphate esters, fatty amide phosphates, polymeric acrylates, fatty amide derivatives, higher alkyl amines, amido amines, substituted imidazolines, substituted betaines, N-alkyl beta amino acid salts, protein derivatives, polyaminocarboxylic acid salts, cationic polyamines, alkyl amides and ethoxylated alkylol amides.
Claim 15
Dependent Claim
15 words
The process of claim 1 wherein the saponifying agent is present during the dispersing step.
Claim 16
Dependent Claim
12 words
The process of claim 14 wherein the saponifying agent is sodium hydroxide.
Claim 17
Dependent Claim
22 words
The process of claim 1 wherein the saponifying agent is added to the dispersed copolymer at the commencement of the saponifying step.
Claim 18
Dependent Claim
17 words
The process of claim 1 wherein the saponified copolymer particles are recovered from the aqueous dispersion medium.
References Cited (Backward Citations)
US4100335A
Cited
US4104453A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-04-29 | 1983-10-29 | 1984-04-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-04-29 | 1987-10-29 | 1988-04-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-04-29 | 1991-10-29 | 1992-04-29 | $7700.00 | Window Closed / Lapsed |