Viscosity index improver and lube oil containing the same

• US 20030104955A1
• Filed: 08/07/2002
• Published: 06/05/2003
• Est. Priority Date: 04/06/2001
• Status: Active Grant

• Current Assignee: Sanyo Chemical Industries Limited
• Original Assignee: Sanyo Chemical Industries Limited
• Inventors: Ota, Yoshihisa, Yuki, Tsuyoshi
• Granted Patent: US 6,746,993 B2
• Time in Patent Office: Days
• US Class Current: 508/469
• CPC Class Codes: C10M 145/14 Acrylate; Methacrylate
• CPC Class Codes: C10M 149/04 containing monomers having an unsaturated radical bound to an amino group
• CPC Class Codes: C10M 149/10 containing monomers having an unsaturated radical bound to a nitrogen-containing hetero ring
• CPC Class Codes: C10M 171/00 Lubricating compositions characterised by purely physical criteria, e.g. containing as base-material, thickener or additive, ingredients which are characterised exclusively by their numerically specified physical properties, i.e. containing ingredients which are physically well-defined but for which the chemical nature is either unspecified or only very vaguely indicated chemically defined ingredients C10M101/00 - C10M169/00; petroleum fractions C10M101/02, C10M121/02, C10M159/04
• CPC Class Codes: C10M 2209/04 containing monomers having an unsaturated radical bound to an alcohol or ester thereof; bound to an aldehyde, ketonic, ether, ketal or acetal radical
• CPC Class Codes: C10M 2209/06 containing monomers having an unsaturated radical bound to an acyloxy radical of saturated carboxylic or carbonic acid
• CPC Class Codes: C10M 2209/062 Vinyl esters of saturated carboxylic or carbonic acids, e.g. vinyl acetate
• CPC Class Codes: C10M 2209/084 Acrylate; Methacrylate
• CPC Class Codes: C10M 2217/02 Macromolecular compounds obtained from nitrogen containing monomers by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: C10M 2217/022 containing monomers having an unsaturated radical bound to an amino group
• CPC Class Codes: C10M 2217/023 the amino group containing an ester bond
• CPC Class Codes: C10M 2217/028 containing monomers having an unsaturated radical bound to a nitrogen-containing hetero ring
• CPC Class Codes: C10N 2020/01 Physico-chemical properties
• CPC Class Codes: C10N 2020/04 Molecular weight; Molecular weight distribution
• CPC Class Codes: C10N 2020/071 Branched chain compounds
• CPC Class Codes: C10N 2030/02 Pour-point; Viscosity index
• CPC Class Codes: C10N 2040/02 Bearings
• CPC Class Codes: C10N 2040/04 Oil-bath; Gear-boxes; Automatic transmissions; Traction drives
• CPC Class Codes: C10N 2040/042 for automatic transmissions
• CPC Class Codes: C10N 2040/046 for traction drives
• CPC Class Codes: C10N 2040/08 : Hydraulic fluids, e.g. brake-fluids
• CPC Class Codes: C10N 2040/25 : Internal-combustion engines
• CPC Class Codes: C10N 2060/06 : by epoxydes or oxyalkylation reactions
• CPC Class Codes: C10N 2070/00 : Specific manufacturing methods for lubricant compositions
• CPC Class Codes: C10N 2070/02 : Concentrating of additives

Abstract

Viscosity index improvers, are disclosed, comprising the following polymer (A1) or (A0).

Polymer (A1) has a solubility parameter of 8.6-9.4, a crystallizing initiation temperature of −15° C. or less and a steric hindrance factor (F) of 0-13, and comprises units of at least one of (a) C_1-40alkyl group-containing (meth)acrylates, (b) alkyl alkenyl ethers, (c) alkenyl carboxylates and (d) nitrogen-containing unsaturated monomers.

Polymer (A0) comprises units of a branched C_20-40alkyl group-containing (meth)acrylate (a0) capable of providing a homopolymer having a Tc of 5° C. or less and units of another alkyl (meth)acrylate.

Monomers, 2-decyl-tetradecyl methacrylate and 2-decyl-tetradecyl acrylate, are also described, suitable for producing polymers for viscosity index improvers.

Claims

1. A viscosity index improver, which comprises a polymer (A1) having a solubility parameter of 8.6-9.4, a crystallizing initiation temperature of −

15°

C. or less, and a steric hindrance factor (F) of 0-13, said factor F being defined by the following equation;

F=4X+Y 

 

(1)

wherein X and Y represent the total atom numbers at the 6th position and the 7th position, respectively, in the side chains, counted from the backbone;

said polymer (A1) having a weight-average molecular weight of 5,000-2,000,000 and comprising units of at least one monomer selected from the group consisting of;

(a) a monomer represented by the general formula;

 

wherein R⁰ is hydrogen atom or methyl group, R is a C_1-40alkyl group, n is 0 or an integer of 1-20 giving 0-10 on average, A is an alkylene group containing 2-4 carbon atoms, plural A'"'"'s in case of n being at least 2 are the same or different, and the polyoxyalkylene moiety (A0)_n in case of the plural A'"'"'s being different comprises random-wise or block-wise distributed oxyalkylene groups,

(b) an alkyl alkenyl ether,

(c) an alkenyl carboxylate, and

(d) a nitrogen-containing unsaturated monomer.

2. The improver of claim 1, wherein said polymer (A1) contains units of said monomer (a), said monomer (b) or said monomers (a) and (b) in an amount of at least 30% by weight, with or without 0-45% by weight of units of said monomer (c), 0-12% by weight of units of said monomer (d) and 0-20% by weight of units of another monomer.

3. The improver of claim 1, wherein said polymer (A1) is a polymer (A11), comprising units of at least one monomer selected from the group consisting of

a monomer (a0), represented by the general formula (2) wherein R is a branched alkyl group containing 20-40 carbon atoms, and a monomer (a1), represented by the general formula (2) wherein R is a branched alkyl group containing 16-19 carbon atoms.

4. The improver of claim 3, wherein said polymer (A11) comprises 5-90% by weight of units of at least one monomer selected from the group consisting of said monomers (a0) and (a1), and 10-60% by weight of units of an alkyl acrylate or methacrylate (a2) containing 1-4 carbon atoms in the alkyl group, with or without 0-85% by weight of units of at least one selected from the group consisting of an alkyl acrylate or methacrylate (a3) containing 8-15 carbon atoms in the alkyl group and a straight-chain alkyl acrylate or methacrylate (a4) containing 16-18 carbon atoms in the alkyl group.

5. The improver of claim 4, wherein said polymer (A11) further comprises 0.1-10% by weight of units of said monomer (d).

6. The improver of claim 5, wherein said monomer (d) is at least one selected from the group consisting of dimethyl-aminoethyl methacrylate, diethylaminoethyl methacrylate, morpholinoethyl methacrylate, and corresponding acrylates.

7. The improver of claim 1, wherein said polymer (A1) is a polymer (A12), comprising units of 27-40% by weight of an alkyl acrylate or methacrylate (a2) containing 1-4 carbon atoms in the alkyl group, 10-40% by weight of an alkyl acrylate or methacrylate (a31) containing 12-13 carbon atoms in the alkyl group, 10-40% by weight of an alkyl acrylate or methacrylate (a32) containing 14-15 carbon atoms in the alkyl group, and 5-35% by weight of an alkyl acrylate or methacrylate containing 16-40 carbon atoms in the alkyl group.

16. A viscosity improver concentrate, which comprises 10-90% by weight of said improver of claim 1 and 10-90% by weight of a diluent.

18. A lube oil composition, which comprises a major amount of a base oil and 0.5-30% by weight of said improver of claim 1.

19. The composition of claim 18, wherein the base oil has a kinematic viscosity of 1-15 mm²/s at 100°

C. and a viscosity index of at least 80.

8. A viscosity index improver, which comprises a polymer (A0) having a weight-average molecular weight of 5,000-2,000,000, comprising 5-95% by weight of units of at least one monomer (a0) and 5-95% by weight of units of at least one alkyl acrylate or methacrylate other than said monomer (a0);

said monomer (a0) being capable of providing a homopolymer having a crystallizing initiation temperature of 5°

C. or less and represented by the general formula;

9. The improver of claim 8, wherein said branched alkyl group is represented by the general formula:

10. The improver of claim 8, wherein said polymer (A0) has a solubility parameter of 8.6-9.4, a crystallizing initiation temperature of −

15°

C. or less, and a steric hindrance factor F of 0-13, said factor being defined by the following equation;

F=4X+Y 

 

(1)

wherein X and Y represent the total atom numbers at the 6th position and the 7th position, respectively, in the side chains, counted from the backbone.

11. The improver of claim 8, wherein said polymer (A0) has a steric hindrance factor F of 0-10.

12. The improver of claim 8, wherein said polymer (A0) comprises 5-90% by weight of units of said monomer (a0), and 10-60% by weight of units of an alkyl acrylate or methacrylate (a2) containing 1-4 carbon atoms in the alkyl group, with or without 0-85% by weight of units of at least one selected from the group consisting of an alkyl acrylate or methacrylate (a3) containing 8-15 carbon atoms in the alkyl group, a branched alkyl acrylate or methacrylate (a12) containing 16-19 carbon atoms in the alkyl group, a straight-chain alkyl acrylate or methacrylate (a4) containing 16-18 carbon atoms in the alkyl group and a straight-chain alkyl acrylate or methacrylate (a5) containing 20-40 carbon atoms in the alkyl group.

13. The improver of claim 8, wherein said polymer (A0) comprises 10-45% by weight of units of 2-decyl-tetradecyl methacrylate, 20-45% by weight of units of methyl methacrylate, and 10-60% by weight of units of a straight-chain alkyl acrylate or methacrylate containing 10-18 carbon atoms in the alkyl group.

14. The improver of claim 8, wherein said polymer (A0) further comprises 0.1-10% by weight of units of a nitrogen-containing unsaturated monomer (d).

15. The improver of claim 14, wherein said monomer (d) is at least one selected from the group consisting of dimethyl-aminoethyl methacrylate, diethylaminoethyl methacrylate, morpholinoethyl methacrylate, and corresponding acrylates.

17. A viscosity improver concentrate, which comprises 10-90% by weight of said improver of claim 7 and 10-90% by weight of a diluent.

20. A lube oil composition, which comprises a major amount of a base oil and 0.5-30% by weight of said improver of claim 8.

21. The composition of claim 20, wherein the base oil has a kinematic viscosity of 1-15 mm²/s at 100°

C. and a viscosity index of at least 80.

22. A compound of 2-decyl-tetradecyl methacrylate.

23. A compound of 2-decyl-tetradecyl acrylate.

24. A polymer having a weight-average molecular weight of 5,000-2,000,000, comprising units of a compound selected from the group consisting of a compound of 2-decyl-tetradecyl methacrylate and a compound of 2-decyl-tetradecyl acrylate.

25. The polymer of claim 24, which comprises 5-95% by weight of units of the compound of 2-decyl-tetradecyl methacrylate, and 5-95% by weight of units of at least one monomer selecting from the group consisting of:

another alkyl methacrylate or an alkyl acrylate;

an alkyl alkenyl ether;

an alkenyl carboxylate; and

a nitrogen-containing unsaturated monomer.