Patent US5026745A successfully refreshed from Google Patents.
US5026745A
Expired / Lapsed
US
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Biodeteriable plastics and blends
Assignee: Sunoco Inc R&M
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Filing: 1989-06-12
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Granted: 1991-06-25
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Expires: 2009-06-12
Abstract
Abstract Improved mechanical properties have been obtained in a biodeteriable polypropylene by mixing starch with a polypropylene modified with maleic anhydride.
Inventors
- 👤 Richard C. Weil
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 07:03
CPC Classifications
C; C08; C08L; C08L3/00; C08L3/02; C08L51/00; C08L51/06
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
30 words
A biodeteriable composition comprising a blend of (1) a graft-copolymer of maleic anhydride and polypropylene and (2) about 1% to about 50% by weight starch based on the total composition.
Claim 2
Dependent Claim
30 words
A biodeteriable composition comprising a blend of (1) a graft-copolymer of maleic anhydride and polypropylene and (2) about 1% to about 50% by weight starch based on the total composition.
Claim 3
Dependent Claim
12 words
Composition of claim 1 wherein the copolymer is made by reaction extrusion.
Claim 4
Dependent Claim
18 words
Composition of claim 1 wherein the ratio of polypropylene to maleic anhydride is about 1000:1 to about 100:1.
Claim 5
Dependent Claim
23 words
Composition of claim 1 in the form of a film or sheet having a thickness of about 1 mil to about 50 mil.
Claim 6
Dependent Claim
42 words
Method of making a biodeteriable film or sheet comprising blending about 6 wt% to about 50% starch with a polypropylene/maleic anhydride copolymer at a temperature of about 365 to about 440° F., and forming the resulting blend into a film or sheet.
Claim 7
Dependent Claim
42 words
Method of making a biodeteriable film or sheet comprising blending about 6 wt% to about 50% starch with a polypropylene/maleic anhydride copolymer at a temperature of about 365 to about 440° F., and forming the resulting blend into a film or sheet.
Claim 8
Dependent Claim
18 words
Method of claim 5 wherein the polypropylene/maleic anhydride copolymer contains about 0.1 to about 1.0 wt% maleic anhydride.
Claim 9
Dependent Claim
25 words
Composition of claim 1 wherein the starch has the formula (C 6 H 10 O 5 ) n , where n is greater than 1000.
Claim 10
Dependent Claim
10 words
A biodeteriable article formed from the composition of claim 4.
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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) | 1994-06-24 | 1994-12-24 | 1995-06-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-06-24 | 1998-12-24 | 1999-06-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-06-24 | 2002-12-24 | 2003-06-25 | $7700.00 | Window Closed / Lapsed |