Random copolymers for use as base oils or lubricant additives

Patent metadata

Field	Value
Publication number	US-11453837-B2
Application number	US-201917292451-A
Country	US
Kind code	B2
Filing date	Oct 23, 2019
Priority date	Nov 13, 2018
Publication date	Sep 27, 2022
Grant date	Sep 27, 2022

Abstract

The invention relates to random copolymers comprising monomers derived from conjugated dienes and alkyl (meth)acrylates, a method for manufacturing the copolymers, lubricant compositions comprising the copolymers, and the use of the copolymers as additives for lubricant compositions or as a base oil for lubricant compositions. The copolymers are favorably used for driving system lubricating oils, hydraulic oils, engine oils and industrial oil formulations.

First claim

The invention claimed is:

1. A random copolymer, obtainable by polymerizing a monomer composition comprising:
(a) 5 to 55 mol-% of one or more conjugated dienes having 6 carbon atoms or less per molecule;
(b) 10 to 45 mol-% of one or more C 1 -C 6 alkyl(meth)acrylates;
(c) 10 to 70 mol-% of one or more C 7 -C 24 alkyl(meth)acrylates;
(d) 0 to 10 mol-% of one or more esters of (meth)acrylic acid and a hydroxylated hydrogenated polybutadiene; and
(e) 0 to 10 mol-% of one or more 1-alkenes comprising 6 to 16 carbon atoms;
based on the total amount of monomers in the monomer composition;
wherein the monomer units derived from the conjugated dienes are hydrogenated and the copolymer has a weight-average molecular weight of 5,000 to 20,000 g/mol; and
wherein the sum of all components (a) to (d) adds up to at least 90 mol-%, based on the total amount of monomers in the monomer composition.

2. The copolymer of claim 1 , wherein the monomer composition comprises:
(a) 15 to 55 mol-% of one or more conjugated dienes having 6 carbon atoms or less per molecule;
(b) 10 to 40 mol-% of one or more C 1 -C 6 alkyl(meth)acrylates;
(c) 15 to 55 mol-% of one or more C 7 -C 24 alkyl(meth)acrylates;
(d) 0 to 5 mol-% of one or more esters of (meth)acrylic acid and a hydroxylated hydrogenated polybutadiene; and
(e) 0 to 5 mol-% of one or more 1-alkenes comprising 6 to 16 carbon atoms;
based on the total amount of monomers in the monomer composition.

3. The copolymer of claim 2 , wherein the sum of all components (a) to (d) adds up to 100 mol-%, based on the total amount of monomers in the monomer composition.

4. The copolymer of claim 3 , comprising a PDI of 2.2 to 3.2.

5. The copolymer of claim 4 , wherein:
component (a) comprises butadiene or isoprene;
component (b) comprises a mixture of methyl (meth)acrylate and n-butyl (meth)acrylate;
component (c) comprises one or more C 10 -C 16 alkyl(meth)acrylates.

6. The copolymer of claim 1 , having a weight-average molecular weight of 7,000 to 20,000 g/mol.

7. The copolymer of claim 1 , comprising a PDI of 1.5 to 6.

8. The copolymer of claim 1 , comprising a PDI of 2 to 4.

9. The copolymer of claim 1 , comprising a PDI of 2.2 to 3.2.

10. The copolymer of claim 1 , wherein component (a) comprises butadiene or isoprene.

11. The copolymer of claim 1 , wherein component (b) comprises a mixture of methyl (meth)acrylate and n-butyl (meth)acrylate.

12. The copolymer of claim 1 , wherein component (c) comprises one or more C 10 -C 16 alkyl(meth)acrylates.

13. A method for manufacturing the random copolymer of claim 1 , the method comprising the steps of:
(i) providing the monomer composition of claim 1 ;
(ii) initiating radical polymerization in solution in the monomer composition to obtain a random copolymer; and
(iii) hydrogenating the random copolymer.

14. The method of claim 13 , wherein hydrogenation is performed using a carbon-supported Pd catalyst.

15. The method of claim 14 , wherein hydrogenation is performed at a temperature of 20 to 120° C. and a pressure of 70 to 120 bar.

16. A composition comprising:
(x) at least one base oil; and
(y) one or more copolymers of claim 1 .

17. The composition of claim 1 , wherein the base oil is a polyalphaolefin base oil, an API group III base oil, a mixture of a polyalphaolefin base oil with an API group III base oil, or a mixture of API group III base oils.

18. The composition of claim 17 , comprising 0.05 to 50% by weight of the one or more copolymers of claim 1 , based on the total amount of the lubricant composition.

19. The composition of claim 17 , comprising 1 to 30% by weight, of the copolymer, based on the total amount of the lubricant composition.

20. The composition of claim 17 , wherein the composition is a lubricant with a viscosity index of more than 140 when measured according to ASTM D2270.

Assignees

• Evonik Operations Gmbh

Inventors

• Pletsch Holger
• Schweissinger Emily Clare
• Spohr Hanna
• Reimann Sebastian
• Pera Lars
• Weiland Marius
• Eisenberg Boris
• Shakhvorostov Dmitriy

Classifications

• C10M145/14 Primary

  Acrylate; Methacrylate · CPC title

• C10N2030/02

  Pour-point; Viscosity index · CPC title

• C08F236/06

  Butadiene · CPC title

• C08F220/1812

  C12-(meth)acrylate, e.g. lauryl (meth)acrylate · CPC title

• C10M2209/084

  Acrylate; Methacrylate · CPC title