US4237257A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing low molecular weight styrene series polymers
Assignee: NOF Corp
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Filing: 1978-07-07
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Granted: 1980-12-02
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Expires: 1998-07-07
Abstract
Abstract Styrene-type monomers are polymerized, or mixtures of styrene-type monomers and other vinyl type monomers and copolymerized, at 50°-120° C. using 1-10 wt%, based on the weight of the monomers, of an organic peroxide polymerization initiator whose decomposition temperature at 10 hours of halflife is 40° C. to 70° C. whereby colorless low molecular weight styrene series polymers are obtained at a high yield, using polymerization apparatus of simple structure.
Inventors
- 👤 Yasuo Moriya
- 👤 Takeshi Komai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 23:53
CPC Classifications
C; C08; C08F; C08F12/00; C08F12/02; C08F12/04; C08F12/06; C08F12/08
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
114 words
A process for preparing a polymer having a number average molecular weight of less than 5000, which consists essentially of polymerizing styrene monomer and up to less than 50 mole percent of a different vinyl monomer which is copolymerizable with said styrene monomer, in the presence of from 3 to 10 percent by weight, based on the weight of said monomers, of organic peroxide polymerization initiator whose decomposition temperature for 10 hour half-life in 0.1 molar solution in benzene is from 40° to 70° C., at a polymerization temperature which is from 20° to 30° C. higher than said decomposition temperature of said initiator, until said polymer is formed, and then recovering said polymer.
Claim 2
Dependent Claim
114 words
A process for preparing a polymer having a number average molecular weight of less than 5000, which consists essentially of polymerizing styrene monomer and up to less than 50 mole percent of a different vinyl monomer which is copolymerizable with said styrene monomer, in the presence of from 3 to 10 percent by weight, based on the weight of said monomers, of organic peroxide polymerization initiator whose decomposition temperature for 10 hour half-life in 0.1 molar solution in benzene is from 40° to 70° C., at a polymerization temperature which is from 20° to 30° C. higher than said decomposition temperature of said initiator, until said polymer is formed, and then recovering said polymer.
Claim 3
Dependent Claim
17 words
A process as claimed in claim 1 in which the polymerizing step is performed by bulk polymerization.
Claim 4
Dependent Claim
17 words
A process as claimed in claim 1 in which the polymerizing step is performed by suspension polymerization.
Claim 5
Dependent Claim
19 words
A process as claimed in claim 2 or claim 3 in which said initiator consists of an organic peroxydicarbonate.
Claim 6
Dependent Claim
27 words
A process as claimed in claim 2 or claim 3 in which said initiator is selected from the group consisting of diisopropyl peroxydicarbonate, di-n-propyl peroxydicarbonate and di(2ethoxy-ethyl)peroxydicarbonate.
Claim 7
Dependent Claim
20 words
A process as claimed in claim 2 or claim 3 in which said initiator consists of an organic peroxy ester.
Claim 8
Dependent Claim
25 words
A process as claimed in claim 2 or claim 3 in which said initiator is selected from the group consisting of tert-butyl peroxydodecanoate and tert-butylperoxypivalate.
Claim 9
Dependent Claim
20 words
A process as claimed in claim 2 or claim 3 in which said initiator consists of an organic peroxydiacyl compound.
Claim 10
Dependent Claim
31 words
A process as claimed in claim 2 or claim 3 in which said initiator is selected from the group consisting of di(3,5,5-trimethyl hexanoyl) peroxide, di-lauroyl peroxide, di-propionyl peroxide and di-acetyl peroxide.
Claim 11
Dependent Claim
39 words
A process as claimed in claim 1 in which said vinyl monomer is selected from the group consisting of α-methylstyrene, vinyl toluene, bromostyrene, methyl methacrylate, butyl methacrylate, methyl acrylate, dimethyl itaconate, dimethyl maleate, acrylonitrile, vinyl acetate, butadiene and butene.
Claim 12
Dependent Claim
29 words
A process as claimed in claim 1 in which the amount of said initiator is from 3 to 8 percent by weight, based on the weight of said monomers.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-12-02 | 1984-06-02 | 1984-12-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-12-02 | 1988-06-02 | 1988-12-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-12-02 | 1992-06-02 | 1992-12-02 | $7700.00 | Window Closed / Lapsed |