Patent US4748215A successfully refreshed from Google Patents.
US4748215A
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Diorganosiloxane polymer powder
Assignee: Bayer AG
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Filing: 1986-09-22
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Granted: 1988-05-31
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Expires: 2006-09-22
Abstract
Abstract The invention relates to pulverulent diorganosiloxane polymers and a process for the preparation of such powders.
Inventors
- 👤 Christian Lindner
- 👤 Wolfgang Grape
- 👤 Hans-Jurgen Kress
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 17:45
CPC Classifications
C; C08; C08F; C08F283/00; C08F283/12; C08F283/124
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
82 words
Process for the preparation of diorganosiloxane polymers in powder form having particles with an average diameter of 0.01-10 mm, wherein an emulsion of a diorganosiloxane polymer is completely broken to form a suspension of diorganosiloxane polymer particles, 2-20% by weight, based on the siloxane polymer, of vinyl monomers which form polymers with glass transition temperatures above 25° C. are then introduced into the suspension and are then polymerized onto the siloxane polymer particles, optionally after addition of catalysts which form free radicals.
Claim 2
Dependent Claim
82 words
Process for the preparation of diorganosiloxane polymers in powder form having particles with an average diameter of 0.01-10 mm, wherein an emulsion of a diorganosiloxane polymer is completely broken to form a suspension of diorganosiloxane polymer particles, 2-20% by weight, based on the siloxane polymer, of vinyl monomers which form polymers with glass transition temperatures above 25° C. are then introduced into the suspension and are then polymerized onto the siloxane polymer particles, optionally after addition of catalysts which form free radicals.
Claim 3
Dependent Claim
57 words
A diorganosiloxane polymer in powder form having particles with an average diameter of 0.01-10 mm comprising a diorganosiloxane polymer having a molecular weight of at least 30,000 and having polymerized thereon from 2 to 20% by weight, based on the diorganosiloxane polymer, of a polymer or copolymer of styrene, acrylonitrile, methacrylonitrile, and alkyl methacrylate or combinations thereof.
Claim 4
Dependent Claim
57 words
A diorganosiloxane polymer in powder form having particles with an average diameter of 0.01-10 mm comprising a diorganosiloxane polymer having a molecular weight of at least 30,000 and having polymerized thereon from 2 to 20% by weight, based on the diorganosiloxane polymer, of a polymer or copolymer of styrene, acrylonitrile, methacrylonitrile, and alkyl methacrylate or combinations thereof.
Claim 5
Dependent Claim
15 words
Diorganosiloxane polymers according to claim 2 wherein the diorganosiloxane polymers are at least partly crosslinked.
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) | 1991-05-31 | 1991-11-30 | 1992-05-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-05-31 | 1995-11-30 | 1996-05-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-05-31 | 1999-11-30 | 2000-05-31 | $7700.00 | Window Closed / Lapsed |