US4298702A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the manufacture of flame retardant polystyrene foams
Assignee: BASF SE
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Filing: 1980-08-04
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Granted: 1981-11-03
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Expires: 2000-08-04
Abstract
Abstract This invention relates to a process of making flame-retardant polystyrene foams by an extrusion process in which a stabilizer of a dialkyl-tin carboxylate or a mixture of a dialkyl tin carboxylate and a barium and/or cadmium carboxylate is added to the extrusion melt.
Inventors
- 👤 Klaus Hahn
- 👤 Klaus Hinselmann
- 👤 Klaus Halbritter
- 👤 Walter Rebafka
- 👤 Heinz Weber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:12
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/0014; C08J9/0052; C08J2325/00; C08J2325/02; C08J2325/04; Y; Y10; Y10S; Y10S260/00; Y10S260/24; Y10S521/00; Y10S521/907
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
122 words
In a process for the manufacture of a flame-retardant polystyrene foam by melting polystyrene in an extruder, mixing the polystyrene at a temperature over 180° C. with 5 weight percent to 20 weight percent, based on the weight of polystyrene, of a volatile blowing agent and 0.5 weight percent to 10 weight percent, based on the weight of polystyrene, of an organic halogen compound extruding the mixture into the surrounding atmosphere, and subsequently cooling the foam, the improvement which comprises adding from 0.01 weight percent to 5 weight percent, based on the weight of polystyrene, of a dialkyl-tin carboxylate, and 0.01 weight percent to 5 weight percent, based on the weight of polystyrene, of a barium and/or cadmium carboxylate to the mixture.
Claim 2
Dependent Claim
122 words
In a process for the manufacture of a flame-retardant polystyrene foam by melting polystyrene in an extruder, mixing the polystyrene at a temperature over 180° C. with 5 weight percent to 20 weight percent, based on the weight of polystyrene, of a volatile blowing agent and 0.5 weight percent to 10 weight percent, based on the weight of polystyrene, of an organic halogen compound extruding the mixture into the surrounding atmosphere, and subsequently cooling the foam, the improvement which comprises adding from 0.01 weight percent to 5 weight percent, based on the weight of polystyrene, of a dialkyl-tin carboxylate, and 0.01 weight percent to 5 weight percent, based on the weight of polystyrene, of a barium and/or cadmium carboxylate to the mixture.
Claim 3
Dependent Claim
13 words
The process of claim 1 in which the dialkyl-tin carboxylate is dibutyltin dilaurate.
Claim 4
Dependent Claim
13 words
The process of claim 1 in which the dialkyl-tin carboxylate is dibutyltin maleate.
Claim 5
Dependent Claim
13 words
The process of claim 1 in which the cadmium carboxylate is cadmium stearate.
Claim 6
Dependent Claim
13 words
The process of claim 1 in which the barium carboxylate is barium stearate.
Claim 7
Dependent Claim
13 words
The process of claim 1 in which the cadmium carboxylate is cadmium palmitate.
Claim 8
Dependent Claim
13 words
The process of claim 1 in which the barium carboxylate is barium palmitate.
Claim 9
Dependent Claim
47 words
The process of claim 1 in which 0.05 weight percent to 1 weight percent, based on the weight of polystyrene, of the dialkyl tin carboxylate, and 0.05 weight percent to 1 weight percent, based on the weight of polystyrene of a barium and/or cadmium carboxylate is added.
Claim 10
Dependent Claim
42 words
The process of claim 1 in which about 0.1 to 0.3 weight percent dialkyltin carboxylate, 0.03 to 0.07 weight percent of a cadmium carboxylate and 0.03 to 0.07 weight percent of a barium carboxylate are added to the mixture as a stabilizer.
Claim 11
Dependent Claim
22 words
The process of claim 1 in which about 0.3 weight percent dialkyltin carboxylate and about 0.1 weight percent cadmium carboxylate is added.
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) | 1984-11-02 | 1985-05-04 | 1985-11-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-11-02 | 1989-05-04 | 1989-11-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-11-02 | 1993-05-04 | 1993-11-03 | $7700.00 | Window Closed / Lapsed |