US4144153A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Radiation process for producing 1,2-polybutadiene foamed products
Assignee: Takiron Co Ltd
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Filing: 1976-10-01
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Granted: 1979-03-13
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Expires: 1996-10-01
Abstract
Abstract A process for producing a photodegradable rubber foamed products of excellent softness, which comprises mixing 1,2-polybutadiene with 0.1 to 3.0% of a photosensitizer and with a thermally decomposable foaming agent, irradiating with ultraviolet ray of a wavelength of 240 to 400 mμ for 10 minutes or less to form a cross-linked material having a gel fraction of 30 to 80% (in boiling toluene; 7 hours), and heating to 150 to 230° C. to form a foamed product. In particularly preferred embodiments of this invention, the foaming agent is p,p'-oxybis (benzenesulfonylhydrazide).
Inventors
- 👤 Yasuo Shikinami
- 👤 Ryuichi Kimura
- 👤 Yoshinobu Yoshikawa
- 👤 Kosuke Iida
- 👤 Kunihiro Hata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 04:46
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/0014; C08J9/0023; C08J2309/00; Y; Y10; Y10S; Y10S260/00; Y10S260/43; Y10S521/00; Y10S521/915; Y10S521/916
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
128 words
A process for producing a photodegradable rubber foam product which comprises, in sequence: mixing essentially 1,2-polybutadiene with 0.1 to 3% of a photosensitizer and with a thermally decomposable foaming agent, said 1,2-polybutadiene having about 70% or more 1,2-bonds, a molecular weight of not less than 100,000, a degree of crystallinity of about 10 to about 50% and 20% or more of a syndiotactic stero specific structure; irradiating the resulting mixture with ultraviolet irradiation of a wavelength of 240 to 400 mμ for about 10 minutes or less to form a cross-linked material having a gel fraction of 30 to 80% (in boiling toluene; 7 hours); and heating the resulting cross-linked material to 150° to 230° C. to decompose the foaming agent and produce a photodegradable rubber foam product.
Claim 2
Dependent Claim
128 words
A process for producing a photodegradable rubber foam product which comprises, in sequence: mixing essentially 1,2-polybutadiene with 0.1 to 3% of a photosensitizer and with a thermally decomposable foaming agent, said 1,2-polybutadiene having about 70% or more 1,2-bonds, a molecular weight of not less than 100,000, a degree of crystallinity of about 10 to about 50% and 20% or more of a syndiotactic stero specific structure; irradiating the resulting mixture with ultraviolet irradiation of a wavelength of 240 to 400 mμ for about 10 minutes or less to form a cross-linked material having a gel fraction of 30 to 80% (in boiling toluene; 7 hours); and heating the resulting cross-linked material to 150° to 230° C. to decompose the foaming agent and produce a photodegradable rubber foam product.
Claim 3
Dependent Claim
20 words
A process of claim 1, wherein said photosensitizer is an aromatic ketone, an aromatic aldehyde or a quinone aromatic compound.
Claim 4
Dependent Claim
33 words
The process of claim 2 wherein said photosensitizer is benzophenone, p,p'-dimethoxybenzophenone, p,p'-dichlorobenzophenone, p,p'-dimethylbenzophenone, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin butyl ether, methyl-O-benzoyl benzoate, benzil, fluorenone, terephthalaldehyde or methyl anthraquinone.
Claim 5
Dependent Claim
30 words
The process of claim 1 wherein said foaming agent is added in an amount of about 0 to about 20 parts by weight per 100 parts by weight of 1,2-polybutadiene.
Claim 6
Dependent Claim
15 words
The process of claim 4 wherein said foaming agent is azodicarbonamide, dinitrosopentamethylenetetramine, p-toluenesulfonylhydrazide or p,p'-oxybis(benzenesulfonylhydrazide).
Claim 7
Dependent Claim
11 words
The process of claim 5 wherein said foaming agent is p,p'-oxybis(benzenesulfonylhydrazide).
Claim 8
Dependent Claim
18 words
The process of claim 1 wherein the irradiating with ultraviolet rays is for at least about 15 seconds.
Claim 9
Dependent Claim
15 words
The process of claim 1 whereby a photodegradable rubber foamed product can be continuously produced.
Claim 10
Dependent Claim
13 words
The process of claim 1 which consists essentially of the steps recited therein.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-03-12 | 1982-09-11 | 1983-03-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-03-12 | 1986-09-11 | 1987-03-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-03-12 | 1990-09-11 | 1991-03-13 | $7700.00 | Window Closed / Lapsed |