← Back to Patent Explorer
US4281081A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for graft copolymerization

Assignee: Roehm GmbH Darmstadt
•
Filing: 1979-02-01
•
Granted: 1981-07-28
•
Expires: 1999-02-01
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract What is disclosed are the method of making a lubricating-oil additive which improves the viscosity index and has a dispersing and detergent action, which method comprises graft copolymerizing, onto an oil-soluble base polymer, from 0.5 to 10 parts of a polymerizable lactam together with 0.1 to 3 parts of a polymerizable N-heterocyclic compound, said parts being by weight of said base polymer, and the lubricating-oil additives so produced.

Inventors

  • 👤 Heinz Jost
  • 👤 Hellmuth Knoell
  • 👤 Gerhard Markert
  • 👤 Horst Pennewiss

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 19:07
CPC Classifications
C; C10; C10M; C10M149/00; C10M149/02; C10M149/10; C08; C08F; C08F255/00; C08F255/02; C08F255/04; C08F265/00; C08F265/04; C10M2217/00; C10M2217/02; C10M2217/028; C10M2217/06

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 83 words
The method of making a lubricating-oil additive which improves the viscosity index and has a dispersing and detergent action, which method comprises graft copolymerizing 0.5 to 10 percent of N-vinyl pyrrolidone together with 0.1 to 3 percent of N-vinyl imidazole onto an oil-soluble base polymer selected from the group consisting of polyalkyl methacrylic acid esters of alcohols having at least 8 carbon atoms and mixtures of said polyalkyl methacrylic acid esters with a polyolefin, said percentages being by weight of said base polymer.
Claim 2
Independent Claim 83 words
The method of making a lubricating-oil additive which improves the viscosity index and has a dispersing and detergent action, which method comprises graft copolymerizing 0.5 to 10 percent of N-vinyl pyrrolidone together with 0.1 to 3 percent of N-vinyl imidazole onto an oil-soluble base polymer selected from the group consisting of polyalkyl methacrylic acid esters of alcohols having at least 8 carbon atoms and mixtures of said polyalkyl methacrylic acid esters with a polyolefin, said percentages being by weight of said base polymer.
Claim 3
Dependent Claim 16 words
A method as in claim 1 wherein said graft copolymerization is carried out in an extruder.
Claim 4
Dependent Claim 24 words
A method as in claim 1 wherein the ratio by weight of said N-vinyl pyrrolidone to said N-vinyl imidazole is from 2:1 to 5:1.
Claim 5
Dependent Claim 37 words
A method as in claim 1 wherein from 1 to 5 percent of N-vinyl pyrrolidone and from 0.2 to 2 percent of N-vinyl imidazole, by weight of said base polymer, are graft copolymerized onto said base polymer.
Claim 6
Dependent Claim 10 words
A lubricating-oil additive prepared by the method of claim 1.
Claim 7
Dependent Claim 10 words
A lubricating-oil additive prepared by the method of claim 2.

References Cited (Backward Citations)

US3089832A Cited
US3067163A Cited
GB1244435A Cited
US4146489A Cited
US4146489B1 Cited
US4098710A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-07-27 1985-01-26 1985-07-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-07-27 1989-01-26 1989-07-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-07-27 1993-01-26 1993-07-28 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag