US4228246A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Manufacture of fluorocarbon expanded polystyrene
Assignee: Honeywell International Inc
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Filing: 1975-11-26
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Granted: 1980-10-14
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Expires: 1995-11-26
Abstract
Abstract Improved polyolefin foams, particularly polystyrene foams, and improved extrusion processability thereof are obtained by employing as blowing agent a mixture of from about 3 to about 70 weight percent monochloromonofluoromethane and from about 97 to about 30 weight percent of dichlorodifluoromethane.
Inventors
- 👤 Bernard Taub
- 👤 Daniel F. Harnish
- 👤 Philip E. Jones
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 18:02
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/04; C08J9/12; C08J9/14; C08J9/143; Y; Y10; Y10S; Y10S264/00; Y10S264/05; Y10S521/00; Y10S521/91
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
67 words
In the process for the preparation of polyolefin foams comprising blending a thermoplastic polyolefin with a nucleating agent and a volatile foaming agent, and extruding said composition into a region of lower pressure to cause foaming; the improvement which comprises employing as the volatile foaming agent, a mixture comprising from about 3 to about 70 weight percent monochloromonofluoromethane and from 97 to about 30 weight percent dichlorodifluoromethane.
Claim 2
Dependent Claim
67 words
In the process for the preparation of polyolefin foams comprising blending a thermoplastic polyolefin with a nucleating agent and a volatile foaming agent, and extruding said composition into a region of lower pressure to cause foaming; the improvement which comprises employing as the volatile foaming agent, a mixture comprising from about 3 to about 70 weight percent monochloromonofluoromethane and from 97 to about 30 weight percent dichlorodifluoromethane.
Claim 3
Dependent Claim
51 words
The process according to claim 1 in which the polyolefin is a monovinyl aromatic compound of the formula Ar--CH═CH 2 wherein Ar is an aromatic hydrocarbon radical of the benzene series or an aromatic halohydrocarbon of the benzene series with up to 10 weight percent of another readily copolymerizable olefinic compound.
Claim 4
Dependent Claim
11 words
The process according to claim 2 wherein the polyolefin is polystyrene.
Claim 5
Dependent Claim
29 words
The process according to claim 3 in which the volatile foaming agent comprises from about 5-50 weight percent monochloromonofluoromethane and from about 95 to about 50 weight percent dichlorodifluoromethane.
Claim 6
Dependent Claim
25 words
The process according to claim 4 wherein the volatile foaming agent comprises from about 10-35 weight percent monochloromonofluoromethane and from about 90-55 weight percent dichlorodifluoromethane.
Claim 7
Dependent Claim
25 words
The process according to claim 5 wherein the volatile blowing agent comprises from about 10-22 weight percent monochloromonofluoromethane and from about 90-78 weight percent dichlorodifluoromethane.
References Cited (Backward Citations)
US3900433A
Cited
US3914191A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-10-14 | 1984-04-14 | 1984-10-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-10-14 | 1988-04-14 | 1988-10-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-10-14 | 1992-04-14 | 1992-10-14 | $7700.00 | Window Closed / Lapsed |