Patent US3948843A successfully refreshed from Google Patents.
← Back to Patent Explorer
US3948843A Expired / Lapsed US ⏱️ 0.0 years remaining

Additives for oils

Assignee: Rhone Progil SA
•
Filing: 1974-03-28
•
Granted: 1976-04-06
•
Expires: 1994-03-28
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract Additives for oils prepared by polymerizing by an anionic process at least one vinyl aromatic compound and at least one conjugated diene in the presence of a solvent, followed by hydrogenation of the formed copolymer in the presence of the solvent, in which the solvent is a support oil having a viscosity within the range of 1 to 24 cst at 50°C, a flash point of at least 120°C and a pour point which is no greater than -10°C.

Inventors

  • 👤 Francoise Saint-Pierre
  • 👤 Bernard Chauvel

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 19:38
CPC Classifications
C; C10; C10M; C10M143/00; C10M143/12; C10M2203/00; C10M2203/06; C10M2205/00; C10M2205/02; C10M2205/026; C10M2205/06; C10M2215/00; C10M2215/086; C10M2215/24; C10M2215/28; C10M2219/00; C10M2219/08; C10M2219/082; C10M2219/087; C10M2219/088; C10M2219/089; C10M2223/00; C10M2223/02; C10M2223/04; C10M2223/042; C10M2223/045; C10N; C10N2020/00; C10N2020/01; C10N2040/00; C10N2040/08; C10N2070/00; C10N2070/02

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 147 words
A method for the preparation of an additive for oils which comprises polymerizing by an anionic process, in the presence of a catalyst consisting of an organo lithium compound at least one vinyl aromatic compound and of at least one conjugated diene in the presence of a solvent, the copolymer obtained having a mean molecular weight within the range of 25,000 to 125,000 and a weight ratio of vinyl aromatic compound to conjugated diene compound from 20/80 to 70/30, hydrogenating olefinic bonds of said polymer in the presence of the same solvent, the solvent being a support oil having a viscosity from 1 to 24 cst at 50°C, a flash point of at least 120°C and a pour point not greater than -10°C, and being employed in an amount such that the concentration of hydrogenated copolymer in said oil is within the range of 5-30% by weight.
Claim 2
Independent Claim 147 words
A method for the preparation of an additive for oils which comprises polymerizing by an anionic process, in the presence of a catalyst consisting of an organo lithium compound at least one vinyl aromatic compound and of at least one conjugated diene in the presence of a solvent, the copolymer obtained having a mean molecular weight within the range of 25,000 to 125,000 and a weight ratio of vinyl aromatic compound to conjugated diene compound from 20/80 to 70/30, hydrogenating olefinic bonds of said polymer in the presence of the same solvent, the solvent being a support oil having a viscosity from 1 to 24 cst at 50°C, a flash point of at least 120°C and a pour point not greater than -10°C, and being employed in an amount such that the concentration of hydrogenated copolymer in said oil is within the range of 5-30% by weight.
Claim 3
Dependent Claim 23 words
A method as claimed in claim 1, in which the support oil has a viscosity of from 3 to 24 cst at 50°C.
Claim 4
Dependent Claim 64 words
A method as claimed in claim 1, in which the support oil is selected from the group consisting of petroleum oils having a paraffinic tendency; fluid oils having a naphthenic tendency; hydrorefined oils; alkyl benzenes containing at least 10 carbon atoms in their alkyl chain, and saturated derivatives of these; branched paraffinic heavy solvents; and polyisobutenes of mean molecular weight from 300 to 500.
Claim 5
Dependent Claim 36 words
A method as claimed in claim 1, in which the vinyl aromatic compound is selected from the group consisting of styrene and the alkyl styrenes and the conjugated diene is isoprene, butadiene or a mixture thereof.
Claim 6
Dependent Claim 20 words
A method as claimed in claim 1, in which the copolymerization is performed at a temperature from 20° to 80°C.
Claim 7
Dependent Claim 21 words
A method as claimed in claim 5, in which the copolymerization is carried out at a temperature from 40° to 60°C.
Claim 8
Dependent Claim 37 words
A method as claimed in claim 1, in which the quantity of catalyst used is from 2 × 10.sup. -4 to 4 × 10.sup. -3 moles of lithium per 100 g of the monomers to be polymerized.
Claim 9
Dependent Claim 28 words
A method as claimed in claim 1, in which the copolymer is a statistical copolymer and the copolymerization is carried out in the presence of a polar solvent.
Claim 10
Dependent Claim 34 words
A method as claimed in claim 8, in which the polar solvent is tetrahydrofuran and is present in an amount from 0.1 to 5 parts by weight per 100 parts by weight of monomers.
Claim 11
Dependent Claim 29 words
A method as claimed in claim 1, in which hydrogenation is carried out in the presence of an organic transition metal salt-trialkyl aluminum catalyst or a reduced nickel/kieselguhr catalyst.

References Cited (Backward Citations)

US2996459A Cited
US3113986A Cited
US3205278A Cited
US3756977A Cited
US3595942A Cited
US3827999A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-04-06 1979-10-06 1980-04-06 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-04-06 1983-10-06 1984-04-06 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-04-06 1987-10-06 1988-04-06 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag