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US4502972A
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Lubricating oil composition containing a dialkyl dithiocarbamate-modified EPDM viscosity index improver
Assignee: Ethyl Corp
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Filing: 1982-06-25
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Granted: 1985-03-05
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Expires: 2002-06-25
Abstract
Abstract The viscosity index and wear inhibiting properties of lubricating oil are improved by adding an effective amount of a 20,000-300,000 molecular weight olefin copolymer to which are grafted di-C1-20 alkyl dithiocarbamate groups.
Inventors
- 👤 Bryan T. Davis
- 👤 Jackson C. Chen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 16:25
CPC Classifications
C; C10; C10M; C10M143/00; C08; C08F; C08F8/00; C08F8/34; C10M2221/00; C10M2221/04; C10M2221/041; C10M2225/00; C10M2225/04; C10M2225/041
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
84 words
A viscosity index improving additive having wear inhibiting properties, said additive comprising a polymeric backbone containing ethylene, propylene and non-conjugated diene units to which is bonded a di-C 1-20 alkyl dithiocarbamate group, said additive being made by the process of reacting a halogen with a copolymer of ethylene, propylene and a non-conjugated diene to form a halogen-substituted copolymer, said copolymer having an average molecular weight of about 20,000 to 300,000 and then reacting said halogen-substituted copolymer with an alkali metal di-C 1-20 alkyl dithiocarbamate.
Claim 2
Dependent Claim
84 words
A viscosity index improving additive having wear inhibiting properties, said additive comprising a polymeric backbone containing ethylene, propylene and non-conjugated diene units to which is bonded a di-C 1-20 alkyl dithiocarbamate group, said additive being made by the process of reacting a halogen with a copolymer of ethylene, propylene and a non-conjugated diene to form a halogen-substituted copolymer, said copolymer having an average molecular weight of about 20,000 to 300,000 and then reacting said halogen-substituted copolymer with an alkali metal di-C 1-20 alkyl dithiocarbamate.
Claim 3
Dependent Claim
10 words
An additive of claim 1 wherein said halogen is chlorine.
Claim 4
Dependent Claim
11 words
An additive of claim 2 wherein said alkali metal is sodium.
Claim 5
Dependent Claim
12 words
An additive of claim 2 wherein said dithiocarbamate group is dimethyl dithiocarbamate.
Claim 6
Dependent Claim
31 words
A lubricating oil composition containing an amount of an additive of claim 1 which will increase the viscosity index of said oil and improve the wear inhibiting properties of said oil.
Claim 7
Dependent Claim
31 words
A lubricating oil composition containing an amount of an additive of claim 4 which will increase the viscosity index of said oil and improve the wear inhibiting property of said oil.
References Cited (Backward Citations)
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US4207196A
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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) | 1988-03-04 | 1988-09-03 | 1989-03-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-03-04 | 1992-09-03 | 1993-03-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-03-04 | 1996-09-03 | 1997-03-05 | $7700.00 | Window Closed / Lapsed |