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US4029613A
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Antilumping expanding styrene polymers
Assignee: Atlantic Richfield Co
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Filing: 1975-12-29
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Granted: 1977-06-14
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Expires: 1995-12-29
Abstract
Abstract Expandable styrene polymer particles are surface-coated with calcium polysilicate to prevent the particles from lumping together during expansion. The coating is applied by adding 0.02-0.05 part of calcium polysilicate to an aqueous suspension containing 100 parts of polymer particles subsequent to impregnating the mixture with a blowing agent, or by dry-blending polymer particles with the polysilicate.
Inventors
- 👤 John J. Quinlan
- 👤 James J. Garland
- 👤 Jose E. Granda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 13:59
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/22; C08J9/224; C08J2325/00; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982; Y10T428/2991; Y10T428/2998
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
67 words
Expandable styrene polymer particles which will not lump during pre-expansion, comprising styrene polymer particles containing a blowing agent and having on their surface from 0.02 to 0.05 percent by weight based on polymer of hydrated calcium polysilicate consisting of 73-83 percent by weight of silicon dioxide, less than 1 percent by weight aluminum oxide, 3-7 percent by weight of calcium oxide, and 9-20 percent by weight water.
Claim 2
Dependent Claim
67 words
Expandable styrene polymer particles which will not lump during pre-expansion, comprising styrene polymer particles containing a blowing agent and having on their surface from 0.02 to 0.05 percent by weight based on polymer of hydrated calcium polysilicate consisting of 73-83 percent by weight of silicon dioxide, less than 1 percent by weight aluminum oxide, 3-7 percent by weight of calcium oxide, and 9-20 percent by weight water.
Claim 3
Dependent Claim
11 words
The composition of claim 1 wherein said styrene polymer is polystyrene.
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) | 1980-06-13 | 1980-12-13 | 1981-06-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-06-13 | 1984-12-13 | 1985-06-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-06-13 | 1988-12-13 | 1989-06-14 | $7700.00 | Window Closed / Lapsed |