US4340723A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the preparation of a copolymer of α-methylstyrene
Assignee: Stamicarbon BV
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Filing: 1980-12-19
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Granted: 1982-07-20
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Expires: 2000-12-19
Abstract
Abstract An improved process for the preparation of copolymers of alpha -methylstyrene and other co-monomers such as acrylonitrile styrene, methyl methacrylate and the like, wherein a substantially water-immiscible softener is employed, particularly prior to coagulation of the latex formed of the copolymer, whereby an improved product of higher bulk density and easier to employ in a subsequent processing is obtained.
Inventors
- 👤 Wilhelmus G. Duyzings
- 👤 Jozef L. M. van der Loos
- 👤 Jan Tijssen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-10 01:41
CPC Classifications
C; C08; C08F; C08F6/00; C08F6/14; C08F6/22
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
97 words
In processes for the preparation of copolymers of α-methylstyrene and at least one other monomer of the group acrylonitrile, methacrylonitrile, methyl-methacrylate, ethylacrylate and styrene, by aqueous emulsion copolymerization, to form a copolymer latex, and followed by coagulating the latex and recovering and drying the polymer thereby formed, the improvement in combination with said copolymerization wherein said coagulation is effected in the presence of a softener agent for said copolymer of α-methylstyrene, said softener being a solvent for said copolymer and substantially immiscible with water, and having a boiling point below that of the boiling point of α-methylstyrene.
Claim 2
Dependent Claim
97 words
In processes for the preparation of copolymers of α-methylstyrene and at least one other monomer of the group acrylonitrile, methacrylonitrile, methyl-methacrylate, ethylacrylate and styrene, by aqueous emulsion copolymerization, to form a copolymer latex, and followed by coagulating the latex and recovering and drying the polymer thereby formed, the improvement in combination with said copolymerization wherein said coagulation is effected in the presence of a softener agent for said copolymer of α-methylstyrene, said softener being a solvent for said copolymer and substantially immiscible with water, and having a boiling point below that of the boiling point of α-methylstyrene.
Claim 3
Dependent Claim
30 words
The process according to claim 1, wherein said softener, a compound is selected from the group of monocyclic aryl and alkaryl hydrocarbons, lower cycloalkyls, and lower saturated aliphatic chlorinated hydrocarbons.
Claim 4
Dependent Claim
25 words
The process according to any one of the claims 1 or 2, wherein the softener is added to the latex prior to effecting the coagulation.
Claim 5
Dependent Claim
31 words
The process according to any one of the claims 1 or 2, wherein the contact time of the softener and the latex prior to coagulation is between 0.1 and 600 seconds.
Claim 6
Dependent Claim
27 words
The process according to any one of claims 1 or 2, wherein from 0.1 to 5% by volume of softener in relation to the latex is added.
Claim 7
Dependent Claim
27 words
The process according to any one of claims 1 or 2, wherein from 0.25 to 5% by volume of softener in relation to the latex is added.
Claim 8
Dependent Claim
27 words
The process according to any one of claims 1 or 2, wherein from 0.25 to 2% by volume of softener in relation to the latex is added.
References Cited (Backward Citations)
US3108983A
Cited
US3668195A
Cited
US3761455A
Cited
US3875104A
Cited
US4025711A
Cited
US4001486A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-07-19 | 1986-01-18 | 1986-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-07-19 | 1990-01-18 | 1990-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-07-19 | 1994-01-18 | 1994-07-20 | $7700.00 | Window Closed / Lapsed |