Lubricant for diesel engine with enhanced Anti-wear performance

Abstract

A lubricating oil composition is described. The composition includes oil of lubricating viscosity, sulfur-containing wear inhibitor; and polymeric dispersant.

Description

[0001] LUBRICANT FOR DIESEL ENGINE WITH ENHANCED ANTI-WEAR PERFORMANCE CROSS-REFERENCE TO RELATED APPLICATION

[0001] This This application claims the benefit of U.S. Provisional Patent Application No. 63 / 669,789, filed July 11, 2024, which is incorporated by reference herein in its entirety. FIELD OF THE DISCLOSURE

[0002] This disclosure relates to lubricating oil compositions and methods of using the same. More specifically, this disclosure describes compositions comprising sulfur-containing wear inhibitor and polymeric dispersants. BACKGROUND

[0003] For heavy-duty automotive engine oil specifications, one trend is to require enhanced anti-wear performance from formulations containing lower amounts of SAPS (sulfated ash [metals], phosphorous, and sulfur. Conventionally, wear is inhibited via the application of zinc dialkyldithiophosphate (ZnDTP) or organosulfur additives. The tighter chemical box for new proposed category of heavy-duty engine oils limits phosphorus level resulting in reduced concentration of ZnDTP in these oils compromising wear performance of these oils. SUMMARY OF THE INVENTION

[0004] In one aspect, this disclosure is related to a lubricating oil composition comprising: oil of lubricating viscosity; sulfur-containing wear inhibitor; and polymeric dispersant composition. - 1 - EMF_US 86880356v1

[0005] In another aspect, this disclosure is related to a method for improving wear in an internal combustion engine, the method comprising lubricating the engine with a lubricating oil composition comprising: major amount of base oil; sulfur-containing wear inhibitor; and polymeric dispersant. DETAILED DESCRIPTION

[0006] The following terms will be used throughout the specification and will have the following meanings unless otherwise indicated.

[0007] The term “a major amount” of a base oil refers to where the amount of the base oil is at least 40 wt. % of the lubricating oil composition. In some embodiments, “a major amount” of a base oil refers to an amount of the base oil more than 50 wt. %, more than 60 wt. %, more than 70 wt. %, more than 80 wt. %, or more than 90 wt. % of the lubricating oil composition.

[0008] The term “liquid polymer” and / or related terms such as “liquid hydrocarbon polymer” refers to a polymer that is a liquid under ambient temperature and pressure. In some embodiments, the liquid polymers of the present disclosure exhibit KV100 of less than 3000 cSt and can be chemically grafted (e.g., radical initiation, acylating agent, etc.).

[0009] This disclosure relates to a lubricating oil composition comprising a sulfur- containing wear inhibitor and a polymeric dispersant. Sulfur-Containing Wear Inhibitor

[0010] The lubricating oil composition includes a sulfur-containing wear inhibitor which includes sulfurized esters and ashless dithiocarbamates. In some embodiments, the sulfur- containing wear inhibitor is present in about 0.05 wt.% to about 2.0 wt.% based on the total lubricating oil composition, such as from 0.05 wt.% to 1.75 wt.%, 0.05 wt.% to 1.5 wt.%, 0.05 wt.% to 1.25 wt.%, 0.05 wt.% to 1.0 wt.%, 0.05 wt.% to 0.9 wt.%, 0.05 wt.% to 0.8 wt.%, 0.05 wt.% to 0.7 wt.%, 0.1 wt.% to 2.0 wt.%, 0.1 wt.% to 1.75 wt.%, 0.1 wt.% to 1.5 wt.%, 0.1 wt.% to 1.25 wt.%, 0.1 wt.% to 1.0 wt.%, 0.1 wt.% to 0.9 wt.%, 0.1 wt.% to 0.8 wt.% 0.1 wt.% to 0.7 wt.%, 0.2 wt.% to 2.0 wt.%, 0.2 wt.% to 1.75 wt.%, 0.2 wt.% to 1.5 wt.%, 0.2 wt.% to 1.25 wt.%, 0.2 wt.% to 1.0 wt.%, 0.2 wt.% to 0.9 wt.%, 0.2 wt.% to 0.8 wt.%, and 0.2 wt.% to 0.7 wt.% . In some embodiment, the lubricating oil composition includes 100 to 1500 ppm of sulfur from the sulfur-containing wear inhibitor. Sulfurized Esters

[0011] In particular, the sulfurized esters may be sulfurized olefin esters. In some embodiments, the sulfurized olefin ester is a sulfurized fatty acid ester. Sulfurized fatty acid esters can be derived from suitable fatty acids. A detailed description of sulfurized esters, including sulfurized fatty acid esters or sulfurized fatty esters, can be found in U.S. 9,181,511, which is hereby incorporated by reference.

[0012] Sulfurized fatty acid esters can be prepared by any compatible method. For example, sulfurized fatty acid esters can be prepared by reacting sulfur, sulfur monochloride, and / or sulfur dichloride with an unsaturated fatty ester under elevated temperatures. Typical esters include C1-C20 alkyl esters of C8-C24 unsaturated fatty acids, such as palmitoleic, oleic, ricinoleic, petroselinic, vaccenic, linoleic, linolenic, oleostearic, licanic, paranaric, tariric, gadoleic, arachidonic, and cetoleic fatty acids. Particularly good results have been obtained with mixed unsaturated fatty acid esters, such as are obtained from animal fats and vegetable oils, such as tall oil, linseed oil, olive oil, castor oil, peanut oil, rape oil, fish oil, sperm oil, and so forth.

[0013] Exemplary fatty esters include lauryl tallate, methyl oleate, ethyl oleate, lauryl oleate, cetyl oleate, cetyl linoleate, lauryl ricinoleate, oleyl linoleate, oleyl stearate, and alkyl glycerides.

[0014] Cross-sulfurized ester olefins, such as a sulfurized mixture of C10-C25 olefins with fatty acid esters of C10-C25fatty acids and C1-C25alkyl or alkenyl alcohols, wherein the fatty acid and / or the alcohol is unsaturated may also be used.

[0015] Sulfurized olefins are prepared by the reaction of the C3-C6olefin or a low- molecular-weight polyolefin derived therefrom with a sulfur-containing compound such as sulfur, sulfur monochloride, and / or sulfur dichloride.

[0016] Commercially available sulfurized esters include Dover Chemical's Base 10SE, Additin 4412F, Additin RC 2310 or Additin RC2410 all from Rhein Chemie, and Esterol 10SX from Arkema.

[0017] Non-limiting examples of sulfurized esters include the following: O wherein n is from 0 to 20 and R1and R2are independently hydrocarbyl groups. Dithiocarbamates

[0018] In some embodiments, the sulfur-containing wear inhibitor is an ashless (i.e., essentially metal free) dithiocarbamate.

[0019] Suitable dithiocarbamates include, but are not limited to, ashless thiocarbamates or dithiocarbamates such as methylenebis(dialkyldithiocarbamate), ethylenebis(dialkyldithiocarbamate), and isobutyl disulfide-2,2′-bis(dialkyldithiocarbamate) where the alkyl groups of the dialkyldithiocarbamate can preferably have from 1 to 18 carbon atoms, such as 1 to 15 carbon atoms or 1 to 10 carbon atoms. The alkyl group can be a straight- chain alkyl group or a branched-chain alkyl group. Examples include methyl, ethyl, propyl, n- butyl, isobutyl, pentyl, isopentyl, heptyl, octyl, 2-ethylhexyl, nonyl, decyl, and dodecyl.

[0020] Specific examples of ashless dithiocarbamate compounds include, for example, methylene bis(dibutyldithiocarbamate), bis(dimethylthiocarbamoyl)monosulfide, bis(dimethylthiocarbamoyl)disulfide, bis(dibutylthiocarbamoyl)disulfide, bis(diamylthiocarbamoyl)disulfide, and bis(dioctylthiocarbamoyl)disulfide.

[0021] In some embodiments, the ashless dithiocarbamate has the following generalized formula: S S R1R3R4wherein each of R1, R2, R3, group having 1 to 18 carbon atoms and X is sulfur, disulfide, or sulfur-containing alkyl group (e.g., S, S-S, S-CH2-S, S- CH2CH2-S, S-CH2CH2CH2-S, S-CH2CH(CH3)-S. etc.) Polymeric Dispersant

[0022] The lubricating oil composition includes low molecular weight polymeric dispersant. In some embodiments, the polymeric dispersant is present in about 0.5 wt.% to about 4.0 wt.% based on the total lubricating oil composition, such as from 0.5 wt.% to about 3.5 wt.%, 0.5 wt.% to about 3.0 wt.%, 0.5 wt.% to about 2.5 wt.%, 0.5 wt.% to about 2.0 wt.%, 1.0 wt.% to 4.0 wt.%, 1.0 wt.% to 3.5 wt.%, 1.0 wt.% to 3.0 wt.%, 1.0 wt.% to 2.5 wt.%, and 1.0 wt.% to 2.0 wt.%.

[0023] In some embodiments, the low molecular weight polymer dispersant can be represented by the following generalized structure: n wherein A is liquid alkyl imide or alkyl amide; C is independently polyamine, alkyl amine, alkyl ether amine, or alkyl hydroxyl amine; D is 1-(arene- 2-yloxy)propan-2-ol; and wherein n is 1 to 15. In some preferred embodiments, n is 3 to 9. The liquid hydrocarbon polymer has average number molecular weight (Mn) of about 1,500 to about 16,000.

[0024] The low molecular weight polymeric dispersant of this disclosure may be synthesized or obtained by any compatible means. One synthetic approach involves grafting a low molecular weight polymer with an acylating grafting agent, functionalizing the grafted polymer with a nucleophilic compound (e.g., polyamine), and post-treating with an epoxide (e.g., aryl glycidyl ether). Another approach involves grafting a low molecular weight polymer with an allyl or vinyl aminic grafting agent and post-treating with an epoxide (e.g., aryl glycidyl ether).

[0025] In accordance with this disclosure, the low molecular weight polymeric dispersant may be obtained by a series of reaction steps determined by the type of grafting agent used.

[0026] In one series of reactions, the low molecular weight polymeric dispersant can be obtained by i) grafting a liquid hydrocarbon polymer with an acylating grafting agent, ii) functionalizing with a polyamine, and iii) post-treating with an aryl glycidyl ether.

[0027] In another series of reactions, the low molecular weight polymeric dispersant can be obtained by i) grafting a liquid hydrocarbon polymer with an allyl or vinyl aminic grafting agent and ii) post-treating with an aryl glycidyl ether.

[0028] Without being limited by theory, it is believed that the post-treatment step greatly enhances the dispersant properties of the low molecular weight polymeric dispersant. Reaction Product

[0029] In some embodiments, the low molecular weight polymeric dispersant is the reaction product of a liquid hydrocarbon polymer having a number average molecular weight (Mn) from about 1,500 and about 16,000; an acylating grafting agent; a polyamine; and an aryl glycidyl ether.

[0030] In some embodiments, the low molecular weight polymeric dispersant is the reaction product of a liquid hydrocarbon polymer having a number average molecular weight (Mn) from about 1,500 and about 16,000; an allyl or vinyl aminic grafting agent; and an aryl glycidyl ether.

[0031] During the series of reaction steps leading to the reaction product (i.e., low molecular polymeric dispersant), the aryl glycidyl ether is added during the final reaction step (i.e., as a post-treatment).

[0032] The liquid hydrocarbon polymer of this disclosure can be characterized as having a low molecular weight, particularly when compared to olefin copolymers conventionally used as viscosity index improvers. The Mn of the liquid hydrocarbon polymer can be measured by any compatible method such as gel permeation chromatography. Number Average Molecular Weight

[0033] The number average (Mn) molecular weight of the liquid hydrocarbon polymer is from about 1,500 to about 16,000 such as from about 1,500 to about 15,500, about 1,500 to about 15,000, about 1,500 to about 14,500, about 1,500 to about 14,000, about 1,500 to about 13,500, about 1,500 to about 13,000, about 1,500 to about 12,500, about 1,500 to about 12,000, about 1,500 to about 11,500, about 1,500 to about 11,000, about 1,500 to about 10,500, about 1,500 to about 10,000, about 1,500 to about 9,500, about 1,500 to about 9,000, about 1,500 to about 8,500, about 1,500 to about 8,000, about 1,500 to about 7,500, about 1,500 to about 7,000, about 1,500 to about 6,500, about 1,500 to about 6,000, about 1,500 to about 5,500, about 1,500 to about 5,000, about 1,500 to about 4,500, about 1,500 to about 4,000, about 1,500 to about 3,500, about 1,500 to about 3,000, about 1,500 to about 2,500, about 1,500 to about 2,000, about 2,000 to about 16,000, about 2,000 to about 15,500, about 2,000 to about 15,000, about 2,000 to about 14,500, about 2,000 to about 14,000, about 2,000 to about 13,500, about 2,000 to about 13,000, about 2,000 to about 12,500, about 2,000 to about 12,000, about 2,000 to about 11,500, about 2,000 to about 11,000, about 2,000 to about 10,500, about 2,000 to about 10,000, about 2,000 to about 9,500, about 2,000 to about 9,000 about 2,000 to about 8,500, about 2,000 to about 8,000, about 2,000 to about 7,500, about 2,000 to about 7,000, about 2,000 to about 6,500, about 2,000 to about 6,000, about 2,000 to about 5,500, about 2,000 to about 5,000, about 2,000 to about 4,500, about 2,000 to about 4,000, about 2,000 to about 3,500, about 2,000 to about 3,000, about 2,000 to about 2,500, about 2,500 to about 16,000, about 2,500 to about 15,500, about 2,500 to about 15,000, about 2,500 to about 14,500, about 2,500 to about 14,000, about 2,500 to about 13,500, about 2,500 to about 13,000, about 2,500 to about 12,500, about 2,500 to about 12,000, 2,500 to about 11,500, about 2,500 to about 11,000, about 2,500 to about 10,500, about 2,500 to about 10,000, about 2,500 to about 9,500, about 2,500 to about 9,000 about 2,500 to about 8,500, about 2,500 to about 8,000, about 2,500 to about 7,500, about 2,500 to about 7,000, about 2,500 to about 6,500, about 2,500 to about 6,000, about 2,500 to about 5,500, about 2,500 to about 5,000, about 2,500 to about 4,500, about 2,500 to about 4,000, about 2,500 to about 3,500, about 2,500 to about 3,000, about 3,000 to about 16,000, about 3,000 to about 15,500, about 3,000 to about 15,000, about 3,000 to about 14,500, about 3,000 to about 14,000, about 3,000 to about 13,500, about 3,000 to about 13,000, about 3,000 to about 12,500, about 3,000 to about 12,000, 3,000 to about 11,500, about 3,000 to about 11,000, about 3,000 to about 10,500, about 3,000 to about 10,000, about 3,000 to about 9,500, about 3,000 to about 9,000 about 3,000 to about 8,500, about 3,000 to about 8,000, about 3,000 to about 7,500, about 3,000 to about 7,000, about 3,000 to about 6,500, about 3,000 to about 6,000, about 3,000 to about 5,500, about 3,000 to about 5,000, about 3,000 to about 4,500, about 3,000 to about 4,000, about 3,000 to about 3,500, about 3,500 to about 16,000, about 3,500 to about 15,500, about 3,500 to about 15,000, about 3,500 to about 14,500, about 3,500 to about 14,000, about 3,500 to about 13,500, about 3,500 to about 13,000, about 3,500 to about 12,500, about 3,500 to about 12,000, 3,500 to about 11,500, about 3,500 to about 11,000, about 3,500 to about 10,500, about 3,500 to about 10,000, about 3,500 to about 9,500, about 3,500 to about 9,000 about 3,500 to about 8,500, about 3,500 to about 8,000, about 3,500 to about 7,500, about 3,500 to about 7,000, about 3,500 to about 6,500, about 3,500 to about 6,000, about 3,500 to about 5,500, about 3,500 to about 5,000, about 3,500 to about 4,500, about 3,500 to about 4,000, about 4,000 to about 16,000, about 4,000 to about 15,500, about 4,000 to about 15,000, about 4,000 to about 14,500, about 4,000 to about 14,000, about 4,000 to about 13,500, about 4,000 to about 13,000, about 4,000 to about 12,500, about 4,000 to about 12,000, about 4,000 to about 11,500, about 4,000 to about 11,000, about 4,000 to about 10,500, about 4,000 to about 10,000, about 4,000 to about 9,500, about 4,000 to about 9,000 about 4,000 to about 8,500, about 4,000 to about 8,000, about 4,000 to about 7,500, about 4,000 to about 7,000, about 4,000 to about 6,500, about 4,000 to about 6,000, about 4,000 to about 5,500, about 4,000 to about 5,000, about 4,000 to about 4,500, about 4,500 to about 16,000, about 4,500 to about 15,500, about 4,500 to about 15,000, about 4,500 to about 14,500, about 4,500 to about 14,000, about 4,500 to about 13,500, about 4,500 to about 13,000, about 4,500 to about 12,500, about 4,500 to about 12,000, about 4,500 to about 11,500, about 4,500 to about 11,000, about 4,500 to about 10,500, about 4,500 to about 10,000, about 4,500 to about 9,500, about 4,500 to about 9,000 about 4,500 to about 8,500, about 4,500 to about 8,000, about 4,500 to about 7,500, about 4,500 to about 7,000, about 4,500 to about 6,500, about 4,500 to about 6,000, about 4,500 to about 5,500, about 4,500 to about 5,000, about 5,000 to about 16,000, about 5,000 to about 15,500, about 5,000 to about 15,000, about 5,000 to about 14,500, about 5,000 to about 14,000, about 5,000 to about 13,500, about 5,000 to about 13,000, about 5,000 to about 12,500, about 5,000 to about 12,000, about 5,000 to about 11,500, about 5,000 to about 11,000, about 5,000 to about 10,500, about 5,000 to about 10,000, about 5,000 to about 9,500, about 5,000 to about 9,000 about 5,000 to about 8,500, about 5,000 to about 8,000, about 5,000 to about 7,500, about 5,000 to about 7,000, about 5,000 to about 6,500, about 5,000 to about 6,000, about 5,000 to about 5,500, about 5,500 to about 16,000, about 5,500 to about 15,500, about 5,500 to about 15,000, about 5,500 to about 14,500, about 5,500 to about 14,000, about 5,500 to about 13,500, about 5,500 to about 13,000, about 5,500 to about 12,500, about 5,500 to about 12,000, about 5,500 to about 11,500, about 5,500 to about 11,000, about 5,500 to about 10,500, about 5,500 to about 10,000, about 5,500 to about 9,500, about 5,500 to about 9,000 about 5,500 to about 8,500, about 5,500 to about 8,000, about 5,500 to about 7,500, about 5,500 to about 7,000, about 5,500 to about 6,500, about 5,500 to about 6,000, about 6,000 to about 16,000, about 6,000 to about 15,500, about 6,000 to about 15,000, about 6,000 to about 14,500, about 6,000 to about 14,000, about 6,000 to about 13,500, about 6,000 to about 13,000, about 6,000 to about 12,500, about 6,000 to about 12,000, about 6,000 to about 11,500, about 6,000 to about 11,000, about 6,000 to about 10,500, about 6,000 to about 10,000, about 6,000 to about 9,500, about 6,000 to about 9,000, about 6,000 to about 8,500, about 6,000 to about 8,000, about 6,000 to about 7,500, about 6,000 to about 7,000, about 6,000 to about 6,500, about 6,500 to about 16,000, about 6,500 to about 15,500, about 6,500 to about 15,000, about 6,500 to about 14,500, about 6,500 to about 14,000, about 6,500 to about 13,500, about 6,500 to about 13,000, about 6,500 to about 12,500, about 6,500 to about 12,000, 6,500 to about 11,500, about 6,500 to about 11,000, about 6,500 to about 10,500, about 6,500 to about 10,000, about 6,500 to about 9,500, about 6,500 to about 9,000 about 6,500 to about 8,500, about 6,500 to about 8,000, about 6,500 to about 7,500, about 6,500 to about 7,000, about 7,000 to about 16,000, about 7,000 to about 15,500, about 7,000 to about 15,000, about 7,000 to about 14,500, about 7,000 to about 14,000, about 7,000 to about 13,500, about 7,000 to about 13,000, about 7,000 to about 12,500, about 7,000 to about 12,000, about 7,000 to about 11,500, about 7,000 to about 11,000, about 7,000 to about 10,500, about 7,000 to about 10,000, about 7,000 to about 9,500, about 7,000 to about 9,000 about 7,000 to about 8,500, about 7,000 to about 8,000, about 7,000 to about 7,500, about 7,500 to about 16,000, about 7,500 to about 15,500, about 7,500 to about 15,000, about 7,500 to about 14,500, about 7,500 to about 14,000, about 7,500 to about 13,500, about 7,500 to about 13,000, about 7,500 to about 12,500, about 7,500 to about 12,000, 7,500 to about 11,500, about 7,500 to about 11,000, about 7,500 to about 10,500, about 7,500 to about 10,000, about 7,500 to about 9,500, about 7,500 to about 9,000 about 7,500 to about 8,500, about 7,500 to about 8,000, about 8,000 to about 16,000, about 8,000 to about 15,500, about 8,000 to about 15,000, about 8,000 to about 14,500, about 8,000 to about 14,000, about 8,000 to about 13,500, about 8,000 to about 13,000, about 8,000 to about 12,500, about 8,000 to about 12,000, about 8,000 to about 11,500, about 8,000 to about 11,000, about 8,000 to about 10,500, about 8,000 to about 10,000, about 8,000 to about 9,500, about 8,000 to about 9,000, about 8,000 to about 8,500, about 8,500 to about 16,000, about 8,500 to about 15,500, about 8,500 to about 15,000, about 8,500 to about 14,500, about 8,500 to about 14,000, about 8,500 to about 13,500, about 8,500 to about 13,000, about 8,500 to about 12,500, about 8,500 to about 12,000, 8,500 to about 11,500, about 8,500 to about 11,000, about 8,500 to about 10,500, about 8,500 to about 10,000, about 8,500 to about 9,500, about 8,500 to about 9,000, about 9,000 to about 16,000, about 9,000 to about 15,500, about 9,000 to about 15,000, about 9,000 to about 14,500, about 9,000 to about 14,000, about 9,000 to about 13,500, about 9,000 to about 13,000, about 9,000 to about 12,500, about 9,000 to about 12,000, about 9,000 to about 11,500, about 9,000 to about 11,000, about 9,000 to about 10,500, about 9,000 to about 10,000, about 9,000 to about 9,500, about 9,500 to about 16,000, about 9,500 to about 15,500, about 9,500 to about 15,000, about 9,500 to about 14,500, about 9,500 to about 14,000, about 9,500 to about 13,500, about 9,500 to about 13,000, about 9,500 to about 12,500, about 9,500 to about 12,000, about 9,500 to about 11,500, about 9,500 to about 11,000, about 9,500 to about 10,500, about 9,500 to about 10,000, about 10,000 to about 16,000, about 10,000 to about 15,500, about 10,000 to about 15,000, about 10,000 to about 14,500, about 10,000 to about 14,000, about 10,000 to about 13,500, about 10,000 to about 13,000, about 10,000 to about 12,500, about 10,000 to about 12,000, about 10,000 to about 11,500, about 10,000 to about 11,000, about 10,000 to about 10,500, about 10,500 to about 16,000, about 10,500 to about 15,500, about 10,500 to about 15,000, about 10,500 to about 14,500, about 10,500 to about 14,000, about 10,500 to about 13,500, about 10,500 to about 13,000, about 10,500 to about 12,500, about 10,500 to about 12,000, about 10,500 to about 11,500, about 10,500 to about 11,000, about 11,000 to about 16,000, about 11,000 to about 15,500, about 11,000 to about 15,000, about 11,000 to about 14,500, about 11,000 to about 14,000, about 11,000 to about 13,500, about 11,000 to about 13,000, about 11,000 to about 12,500, about 11,000 to about 12,000, about 11,000 to about 11,500, about 11,500 to about 16,000, about 11,500 to about 15,500, about 11,500 to about 15,000, about 11,500 to about 14,500, about 11,500 to about 14,000, about 11,500 to about 13,500, about 11,500 to about 13,000, about 11,500 to about 12,500, about 11,500 to about 12,000, about 12,000 to about 16,000, about 12,000 to about 15,500, about 12,000 to about 15,000, about 12,000 to about 14,500, about 12,000 to about 14,000, about 12,000 to about 13,500, about 12,000 to about 13,000, about 12,000 to about 12,500, about 12,500 to about 16,000, about 12,500 to about 15,500, about 12,500 to about 15,000, about 12,500 to about 14,500, about 12,500 to about 14,000, about 12,500 to about 13,500, about 12,500 to about 13,000, about 13,000 to about 16,000, about 13,000 to about 15,500, about 13,000 to about 15,000, about 13,000 to about 14,500, about 13,000 to about 14,000, about 13,000 to about 13,500, about 13,500 to about 16,000, about 13,500 to about 15,500, about 13,500 to about 15,000, about 13,500 to about 14,500, about 13,500 to about 14,000, about 14,000 to about 16,000, about 14,000 to about 15,500, about 14,000 to about 15,000, about 14,000 to about 14,500, about 14,500 to about 16,000, about 14,500 to about 15,500, about 14,500 to about 15,000, about 15,000 to about 16,000, about 15,000 to about 15,500, or about 15,500 to about 16,000.

[0034] Suitable examples of liquid hydrocarbon polymers include, but are not limited to, ethylene-propylene copolymers, ethylene-based polymers, or propylene-based polymers. Ethylene or propylene-based polymers herein can include blends or reacted products of ethylene or propylene and one or more C4 to C28 alpha-olefins, and additionally optionally other dienes or polyenes and thus may herein also include terpolymers, and other higher forms.

[0035] In some embodiments, the ethylene content of the copolymer is in the range of 10 to 80 percent by weight, such as 10 to 75 percent, 10 to 70 percent, 10 to 65 percent, 10 to 60 percent 10 to 50 percent, 10 to 45 percent, 10 to 40 percent, 10 to 35 percent, 10 to 30 percent 10 to 25 percent 10 to 20 percent, 10 to 15 percent, 15 to 80 percent, 15 to 75 percent, 15 to 70 percent, 15 to 65 percent, 15 to 60 percent, 15 to 55 percent, 15 to 50 percent, 15 to 45 percent, 15 to 40 percent, 15 to 35 percent, 15 to 30 percent, 15 to 25 percent, 15 to 20 percent, 20 to 80 percent, 20 to 75 percent, 20 to 70 percent, 20 to 65 percent, 20 to 60 percent, 20 to 55 percent, 20 to 50 percent, 20 to 45 percent, 20 to 40 percent, 20 to 35 percent, 20 to 30 percent, 20 to 25 percent, 25 to 80 percent, 25 to 75 percent, 25 to 70 percent, 25 to 65 percent, 25 to 60 percent, 25 to 55 percent, 25 to 50 percent, 25 to 45 percent, 25 to 40 percent, 25 to 35 percent, 25 to 30 percent, 30 to 80 percent, 30 to 75 percent, 30 to 70 percent, 30 to 65 percent, 30 to 60 percent, 30 to 55 percent, 30 to 50 percent, 30 to 45 percent, 30 to 40 percent, 30 to 35 percent, 35 to 80 percent, 35 to 75 percent, 35 to 70 percent, 35 to 65 percent, 35 to 60 percent, 35 to 55 percent, 35 to 50 percent, 35 to 45 percent, 35 to 40 percent, 40 to 80 percent, 40 to 75 percent, 40 to 70 percent, 40 to 65 percent, 40 to 60 percent, 40 to 55 percent, 40 to 50 percent, 40 to 45 percent, 45 to 80 percent, 45 to 75 percent, 45 to 70 percent, 45 to 65 percent, 45 to 60 percent, 45 to 55 percent, 45 to 50 percent, 50 to 80 percent, 50 to 75 percent, 50 to 70 percent, 50 to 65 percent, 50 to 60 percent, 50 to 55 percent, 55 to 80 percent, 55 to 75 percent, 55 to 70 percent, 55 to 65 percent, 55 to 60 percent, 60 to 80 percent, 60 to 75 percent, 60 to 70 percent, 60 to 65 percent, 65 to 80 percent, 65 to 75 percent, 65 to 70 percent, 70 to 80 percent, 70 to 75 percent, or 75 to 80 percent.

[0036] In some embodiments, the ethylene-based copolymer is an ethylene-propylene copolymer. The propylene content of the ethylene-propylene copolymer is in the range of 20 to 90 percent by weight, such as 20 to 85 percent, 20 to 80 percent, 20 to 75 percent, 20 to 70 percent, 20 to 65 percent, 20 to 60 percent 20 to 50 percent, 20 to 45 percent, 20 to 40 percent, 20 to 35 percent, 20 to 30 percent 20 to 25 percent, 25 to 90 percent, 25 to 85 percent, 25 to 80 percent, 25 to 75 percent, 25 to 70 percent, 25 to 65 percent, 25 to 60 percent, 25 to 55 percent, 25 to 50 percent, 25 to 45 percent, 25 to 40 percent, 25 to 35 percent, 25 to 30 percent, 30 to 90 percent, 30 to 85 percent, 30 to 80 percent, 30 to 75 percent, 30 to 70 percent, 30 to 65 percent, 30 to 60 percent, 30 to 55 percent, 30 to 50 percent, 30 to 45 percent, 30 to 40 percent, 30 to 35 percent, 35 to 90 percent, 35 to 85 percent, 35 to 80 percent, 35 to 75 percent, 35 to 70 percent, 35 to 65 percent, 35 to 60 percent, 35 to 55 percent, 35 to 50 percent, 35 to 45 percent, 35 to 40 percent, 40 to 90 percent, 40 to 85 percent, 40 to 80 percent, 40 to 75 percent, 40 to 70 percent, 40 to 65 percent, 40 to 60 percent, 40 to 55 percent, 40 to 50 percent, 40 to 45 percent, 45 to 90 percent, 45 to 85 percent, 45 to 80 percent, 45 to 75 percent, 45 to 70 percent, 45 to 65 percent, 45 to 60 percent, 45 to 55 percent, 45 to 50 percent, 50 to 90 percent, 50 to 85 percent, 50 to 80 percent, 50 to 75 percent, 50 to 70 percent, 50 to 65 percent, 50 to 60 percent, 50 to 55 percent, 55 to 90 percent, 55 to 85 percent, 55 to 80 percent, 55 to 75 percent, 55 to 70 percent, 55 to 65 percent, 55 to 60 percent, 60 to 90 percent, 60 to 85 percent, 60 to 80 percent, 60 to 75 percent, 60 to 70 percent, 60 to 65 percent, 65 to 90 percent, 65 to 85 percent, 65 to 80 percent, 65 to 75 percent, 65 to 70 percent, 70 to 90 percent, 70 to 85 percent, 70 to 80 percent, 70 to 75 percent, 75 to 90 percent, 75 to 85 percent, 75 to 80 percent, 80 to 90 percent, 80 to 85 percent, or 85 to 90 percent. Free Radical Initiator

[0037] The grafting reaction can be catalyzed by a free radical initiator. Examples of free radical initiator include peroxides, hydroperoxides, peresters, and also azo compounds and preferably those which have a boiling point greater than 100ºC and decompose thermally within the grafting temperature range to provide free radicals. Representatives of these free-radical initiators are peroxides (diacyl peroxides such as benzoyl peroxide, dialkyl peroxides such as 1,1- bis(tert-butylperoxy)cyclohexane, 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, 2,2- bis(tert-butylperoxy)butane, dicumylperoxide, tert-butylcumylperoxide, bis(tert- butylperoxyisopropyl)benzene, di-tert-butylperoxide (DTBP), di-tert-amylperoxide, 2,5- dimethyl-2,5-di(tert-butylperoxy)hexane, 2,5-dimethyl-2,5-di(tert-butylperoxy)-hexyne), hydroperoxides, peroxyesters such as tert-butyl peroxy benzoate, tert-butylperoxy acetate, O,O- tert-butyl-O-(2-ethylhexyl)monoperoxy carbonate, peroxyketals such as n-butyl 4,4-di-(tert- butylperoxy)valerate and the like. The initiator is typically used in an amount of from about 0.005% and about 1% by weight based on the weight of the reaction mixture solution.

[0038] The grafting is preferably carried out in an inert atmosphere, such as under nitrogen blanketing. A more detailed discussion of free radical initiators can be found in Reactive Modifiers for Polymers Softcover reprint of the original 1st ed.1997 Edition. by S. Al-Malaika (Editor), the relevant parts of which are hereby incorporated by reference. Grafting Agent

[0039] Suitable grafting agents of this disclosure include i) an acylating grafting agent (e.g., ethylenically unsaturated acylating agent) or ii) an allyl or vinyl aminic grafting agent (e.g., allyl amines or vinyl amines). The grafting agents of this disclosure generally feature 2 reaction sites. One reaction site allows the grafting agent to form a chemical linkage with the low molecular weight hydrocarbon polymer. The second reaction site allows the grafting agent to form a chemical linkage with a polyamine in the case of an acylating grafting agent. When allyl or vinyl aminic grafting agent is used, the second reaction site is available for post-treatment with an aryl glycidyl ether. Acylating Grafting Agent

[0040] In some embodiments, the acylating grafting agent is an ethylenically unsaturated acylating agent. In some embodiments, the ethylenically unsaturated acylating agent is a carboxylic acid or functional derivative thereof (including esters and anhydrides). The carboxylic acid may include, for example, acrylic acid, crotonic acid, methyacrylic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, mesaconic acid, glutaconic acid, chloromaleic acid, aconitic acid, methylcrotonic acid, or sorbic acid. In some embodiments, the acylating agent is an ester of the carboxylic acid. In some embodiments, the acylating agent is an anhydride of the carboxylic acid.

[0041] The ethylenically unsaturated carboxylic acid or functional derivative thereof is typically grafted onto the hydrocarbon polymer backbone at about 100ºC to about 250ºC in the presence of a free radical initiator. In this regard, the hydrocarbon polymer backbone has been suitably reacted with the acylating grafting agent in the range of 0.5 to 10.0 wt % of the acylating grafting agent based upon the total mass of polymer. Radical Initiation Using Acylating Grafting Agent A non-limiting example of a radical initiated grafting reaction with an acylating grafting agent (maleic anhydride) is shown below: Allyl or Vinyl Aminic Grafting Agent

[0042] In some embodiments, the grafting agent is allyl or vinyl aminic grafting agent. As alluded to earlier, the allyl or vinyl aminic grafting agent generally includes a first reaction site – an allyl or vinyl group that can react with the polymer and a second reaction site – an amine that can be post-treated by a post-treatment agent such as an aryl glycidyl ether.

[0043] The allyl or vinyl aminic graft agent can be represented by the following generalized structure: WZwherein W is vinyl, alkyl vinyl, allyl, or alkyl allyl group and Z is piperazine, alkylamine, arylamine, formamide, alkyl carbamide, alkyl amide, or aryl amide.

[0044] Specific examples of suitable allyl or vinyl aminic grafting agent include, for example, 1-ethenylpiperazine, 1-(prop-1-en-2-yl)piperazine, 1-allylpiperazine, N- allylmethylamine, allylcyclohexylamine, N-allylaniline, N,2-dimethyl-2-propen-1-amine, N- ethyl-2-methylallylamine, 1-(2-methylprop-2-en-1-yl)piperazine, and N-vinylformamide. Specific examples of suitable allyl or vinyl aminic grafting agents that need deprotection reaction before post-treatment with aryl glycidyl ether include, for example, N-vinylacetamide, N- vinylbenzamide, and methyl vinylcarbamate. Radical Initiation Using Allyl Aminic Grafting Agent

[0045] A non-limiting example of a radical initiated grafting reaction with allyl aminic grafting agent (allyl piperazine) is shown below: free radical initiaor Polyamine

[0046] The polyamines of this disclosure can be used to functionalize acylating grafting agents during the synthesis of the low molecular weight polymeric dispersant. The polyamine used in the synthesis of the low molecular weight polymeric dispersant can be represented by the following generalized structure: H2N X Ywherein X is C2-C10hydrocarbyl group, amino alkyl group, ether group, thioether group, or aromatic group and Y is amino C1-C10 hydrocarbyl group, amino alkyl hydroxyl group, amino alkyl ether group, amino alkyl thioether group, amino aromatic group, or piperazine.

[0047] Particularly useful polyamines include aminoethylpiperazine, aminoethylethanolamine, and N-phenyl-p-phenylenediamine.

[0048] Non-limiting examples of polyamines include the following: N1-ethylpropane-1,3-diamineN1-(2-ethoxyethyl)propane-1,3-diamineH2N NN (3-aminopropyl)- ethylpropane-1,3-diamineH N H N N-phenyl-p-phenylenediamine (NPPDA) Glycidyl Ethers

[0049] The grafted product (when using allyl or vinyl aminic grafting agent) or the polyamine functionalized grafted product (when using acylating grafting agent) includes a second reaction site (aminic nitrogen) which allows for post-treatment with a glycidyl ether. Due to its reactivity, secondary nitrogen is generally more desirable than primary or tertiary nitrogen.

[0050] Suitable examples of aryl glycidyl ethers include, but are not limited to, phenyl glycidyl ether and naphthyl glycidyl ether. O

[0051] Without being limited by theory, it is believed that post-treatment of the grafted product or polyamine functionalized grafted product can greatly enhance soot dispersing capabilities. It is also believed that the presence of a secondary nitrogen on the grafted product or polyamine functionalized grafted product is highly desirable for post-treatment(s) due to the reactivity of secondary nitrogen compared to primary nitrogen or tertiary nitrogen. Molybdenum-containing Additive

[0052] The lubricating oil composition may also include at least one molybdenum- containing additive. The additive is present in an amount to provide between 50 to 100 ppm of Mo to the lubricating oil composition.

[0053] Suitable molybdenum-containing additives include oil-soluble organo- molybdenum compounds, such as molybdenum succinimide. In some embodiments, the organo- molybdenum compound may include a molybdenum-sulfur core wherein the sulfur part is dithiocarbamate dithiophosphate, dithiophosphinate, xanthate, thioxanthate, sulfide, or mixtures thereof. In some embodiments, the molybdenum-containing additive is dinuclear or trinuclear. Other Additives

[0054] Optionally, the lubricating oil composition may further comprise an additive that can impart or improve any desirable property of the lubricating oil composition. Any additive known to a person of ordinary skill in the art may be used in the lubricating oil compositions disclosed herein. Some suitable additives have been described in Mortier et al., "Chemistry and Technology of Lubricants," 2nd Edition. London, Springer, (1996); and Leslie R. Rudnick, "Lubricant Additives: Chemistry and Applications," New York, Marcel Dekker (2003), both of which are incorporated herein by reference. In some embodiments, the additive can be selected from the group consisting of antioxidants, antiwear agents, detergents, rust inhibitors, demulsifiers, friction modifiers, multi-functional additives, viscosity index improvers, pour point depressants, foam inhibitors, metal deactivators, dispersants, corrosion inhibitors, lubricity improvers, thermal stability improvers, anti-haze additives, icing inhibitors, dyes, markers, static dissipaters, biocides and combinations thereof.

[0055] In general, the concentration of each of the additives in the lubricating oil composition, when used, may range from about 0.001 wt. % to about 10 wt. %, from about 0.01 wt. % to about 5 wt. %, or from about 0.1 wt. % to about 2.5 wt. %, based on the total weight of the lubricating oil composition. Further, the total amount of the additives in the lubricating oil composition may range from about 0.001 wt. % to about 20 wt. %, from about 0.01 wt. % to about 10 wt. %, or from about 0.1 wt. % to about 5 wt. %, based on the total weight of the lubricating oil composition. The Oil of Lubricating Viscosity

[0056] The lubricating oil compositions (e.g., finished oils, additive packages diluted base oil, etc.) disclosed herein generally comprise at least one oil of lubricating viscosity. Any base oil known to a skilled artisan can be used as the oil of lubricating viscosity disclosed herein. Some base oils suitable for preparing the lubricating oil compositions have been described in Mortier et al., "Chemistry and Technology of Lubricants," 2nd Edition, London, Springer, Chapters 1 and 2 (1996); and A. Sequeria, Jr., "Lubricant Base Oil and Wax Processing," New York, Marcel Decker, Chapter 6, (1994); and D. V. Brock, Lubrication Engineering, Vol.43, pages 184-5, (1987), all of which are incorporated herein by reference. Generally, the amount of the base oil in the lubricating oil composition may be from about 1 wt.% to about 99.5 wt. %, based on the total weight of the lubricating oil composition. In some embodiments, the amount of the base oil in the lubricating oil composition is from about 50 wt.% to about 99 wt.%, 75 to about 99 wt. %, from about 80 to about 98.5 wt. %, or from about 80 to about 98 wt. %, based on the total weight of the lubricating oil composition.

[0057] In certain embodiments, the base oil is or comprises any natural or synthetic lubricating base oil fraction. Some non-limiting examples of synthetic oils include oils, such as polyalphaolefins or PAOs, prepared from the polymerization of at least one alpha-olefin, such as ethylene, or from hydrocarbon synthesis procedures using carbon monoxide and hydrogen gases, such as the Fisher-Tropsch process. In certain embodiments, the base oil comprises less than about 10 wt. % of one or more heavy fractions, based on the total weight of the base oil. A heavy fraction refers to a lube oil fraction having a viscosity of at least about 20 cSt at 100° C. In certain embodiments, the heavy fraction has a viscosity of at least about 25 cSt or at least about 30 cSt at 100° C. In further embodiments, the amount of the one or more heavy fractions in the base oil is less than about 10 wt. %, less than about 5 wt. %, less than about 2.5 wt. %, less than about 1 wt. %, or less than about 0.1 wt. %, based on the total weight of the base oil. In still further embodiments, the base oil comprises no heavy fraction.

[0058] In certain embodiments, the lubricating oil compositions comprise a major amount of a base oil of lubricating viscosity. In some embodiments, the base oil has a kinematic viscosity at 100° C. from about 2.5 centistokes (cSt) to about 20 cSt, from about 4 centistokes (cSt) to about 20 cSt, or from about 5 cSt to about 16 cSt. The kinematic viscosity of the base oils or the lubricating oil compositions disclosed herein can be measured according to ASTM D 445, which is incorporated herein by reference.

[0059] In other embodiments, the base oil is or comprises a base stock or blend of base stocks. In further embodiments, the base stocks are manufactured using a variety of different processes including, but not limited to, distillation, solvent refining, hydrogen processing, oligomerization, esterification, and rerefining. In some embodiments, the base stocks comprise a rerefined stock. In further embodiments, the rerefined stock shall be substantially free from materials introduced through manufacturing, contamination, or previous use.

[0060] In some embodiments, the base oil comprises one or more of the base stocks in one or more of Groups I-V as specified in the American Petroleum Institute (API) Publication 1509, Fourteen Edition, December 1996 (i.e., API Base Oil Interchangeability Guidelines for Passenger Car Motor Oils and Diesel Engine Oils), which is incorporated herein by reference. The API guideline defines a base stock as a lubricant component that may be manufactured using a variety of different processes. Groups I, II and III base stocks are mineral oils, each with specific ranges of the amount of saturates, sulfur content and viscosity index. Group IV base stocks are polyalphaolefins (PAO). Group V base stocks include all other base stocks not included in Group I, II, III, or IV.

[0061] In some embodiments, the base oil comprises one or more of the base stocks in Group I, II, III, IV, V or a combination thereof. In other embodiments, the base oil comprises one or more of the base stocks in Group II, III, IV or a combination thereof. In further embodiments, the base oil comprises one or more of the base stocks in Group II, III, IV or a combination thereof wherein the base oil has a kinematic viscosity from about 2.5 centistokes (cSt) to about 20 cSt, from about 4 cSt to about 20 cSt, or from about 5 cSt to about 16 cSt at 100° C.

[0062] The base oil may be selected from the group consisting of natural oils of lubricating viscosity, synthetic oils of lubricating viscosity and mixtures thereof. In some embodiments, the base oil includes base stocks obtained by isomerization of synthetic wax and slack wax, as well as hydrocrackate base stocks produced by hydrocracking (rather than solvent extracting) the aromatic and polar components of the crude. In other embodiments, the base oil of lubricating viscosity includes natural oils, such as animal oils, vegetable oils, mineral oils (e.g., liquid petroleum oils and solvent treated or acid-treated mineral oils of the paraffinic, naphthenic or mixed paraffinic- naphthenic types), oils derived from coal or shale, and combinations thereof. Some non-limiting examples of animal oils include bone oil, lanolin, fish oil, lard oil, dolphin oil, seal oil, shark oil, tallow oil, and whale oil. Some non-limiting examples of vegetable oils include castor oil, olive oil, peanut oil, rapeseed oil, corn oil, sesame oil, cottonseed oil, soybean oil, sunflower oil, safflower oil, hemp oil, linseed oil, tung oil, oiticica oil, jojoba oil, and meadow foam oil. Such oils may be partially or fully hydrogenated.

[0063] In some embodiments, the synthetic oils of lubricating viscosity include hydrocarbon oils and halo-substituted hydrocarbon oils such as polymerized and inter-polymerized olefins, alkylbenzenes, polyphenyls, alkylated diphenyl ethers, alkylated diphenyl sulfides, as well as their derivatives, analogues and homologues thereof, and the like. In other embodiments, the synthetic oils include alkylene oxide polymers, interpolymers, copolymers and derivatives thereof wherein the terminal hydroxyl groups can be modified by esterification, etherification, and the like. In further embodiments, the synthetic oils include the esters of dicarboxylic acids with a variety of alcohols. In certain embodiments, the synthetic oils include esters made from C5to C12monocarboxylic acids and polyols and polyol ethers. In further embodiments, the synthetic oils include tri-alkyl phosphate ester oils, such as tri-n-butyl phosphate and tri-iso-butyl phosphate.

[0064] In some embodiments, the synthetic oils of lubricating viscosity include silicon- based oils (such as the polyakyl-, polyaryl-, polyalkoxy-, polyaryloxy-siloxane oils and silicate oils). In other embodiments, the synthetic oils include liquid esters of phosphorus-containing acids, polymeric tetrahydrofurans, polyalphaolefins, and the like.

[0065] Base oil derived from the hydroisomerization of wax may also be used, either alone or in combination with the aforesaid natural and / or synthetic base oil. Such wax isomerate oil is produced by the hydroisomerization of natural or synthetic waxes or mixtures thereof over a hydroisomerization catalyst.

[0066] In further embodiments, the base oil comprises a poly-alpha-olefin (PAO). In general, the poly-alpha-olefins may be derived from an alpha-olefin having from about 2 to about 30, from about 4 to about 20, or from about 6 to about 16 carbon atoms. Non-limiting examples of suitable poly-alpha-olefins include those derived from octene, decene, mixtures thereof, and the like. These poly-alpha-olefins may have a viscosity from about 2 to about 15, from about 3 to about 12, or from about 4 to about 8 centistokes at 100° C. In some instances, the poly-alpha- olefins may be used together with other base oils such as mineral oils.

[0067] In further embodiments, the base oil comprises a polyalkylene glycol or a polyalkylene glycol derivative, where the terminal hydroxyl groups of the polyalkylene glycol may be modified by esterification, etherification, acetylation and the like. Non-limiting examples of suitable polyalkylene glycols include polyethylene glycol, polypropylene glycol, polyisopropylene glycol, and combinations thereof. Non-limiting examples of suitable polyalkylene glycol derivatives include ethers of polyalkylene glycols (e.g., methyl ether of polyisopropylene glycol, diphenyl ether of polyethylene glycol, diethyl ether of polypropylene glycol, etc.), mono- and polycarboxylic esters of polyalkylene glycols, and combinations thereof. In some instances, the polyalkylene glycol or polyalkylene glycol derivative may be used together with other base oils such as poly-alpha-olefins and mineral oils.

[0068] In further embodiments, the base oil comprises any of the esters of dicarboxylic acids (e.g., phthalic acid, succinic acid, alkyl succinic acids, alkenyl succinic acids, maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic acid, linoleic acid dimer, malonic acid, alkyl malonic acids, alkenyl malonic acids, and the like) with a variety of alcohols (e.g., butyl alcohol, hexyl alcohol, dodecyl alcohol, 2-ethylhexyl alcohol, ethylene glycol, diethylene glycol monoether, propylene glycol, and the like). Non-limiting examples of these esters include dibutyl adipate, di(2-ethylhexyl) sebacate, di-n-hexyl fumarate, dioctyl sebacate, diisooctyl azelate, diisodecyl azelate, dioctyl phthalate, didecyl phthalate, dieicosyl sebacate, the 2-ethylhexyl diester of linoleic acid dimer, and the like.

[0069] In further embodiments, the base oil comprises a hydrocarbon prepared by the Fischer-Tropsch process. The Fischer-Tropsch process prepares hydrocarbons from gases containing hydrogen and carbon monoxide using a Fischer-Tropsch catalyst. These hydrocarbons may require further processing in order to be useful as base oils. For example, the hydrocarbons may be dewaxed, hydroisomerized, and / or hydrocracked using processes known to a person of ordinary skill in the art.

[0070] In further embodiments, the base oil comprises an unrefined oil, a refined oil, a rerefined oil, or a mixture thereof. Unrefined oils are those obtained directly from a natural or synthetic source without further purification treatment. Non-limiting examples of unrefined oils include shale oils obtained directly from retorting operations, petroleum oils obtained directly from primary distillation, and ester oils obtained directly from an esterification process and used without further treatment. Refined oils are similar to the unrefined oils except the former have been further treated by one or more purification processes to improve one or more properties. Many such purification processes are known to those skilled in the art such as solvent extraction, secondary distillation, acid or base extraction, filtration, percolation, and the like. Rerefined oils are obtained by applying to refined oils processes similar to those used to obtain refined oils. Such rerefined oils are also known as reclaimed or reprocessed oils and often are additionally treated by processes directed to removal of spent additives and oil breakdown products.

[0071] The following examples are presented to exemplify embodiments but are not intended to limit the application to the specific embodiments set forth. Unless indicated to the contrary, all parts and percentages are by weight. All numerical values are approximate. When numerical ranges are given, it should be understood that embodiments outside the stated ranges may still fall within the scope of the application. Specific details described in each example should not be construed as necessary features. EXAMPLES

[0072] The following examples are intended for illustrative purposes only and do not limit in any way the scope.

[0073] A baseline SAE 10W-30 lubricating oil was prepared by blending the following components with Group II base oil: a) mixture of borated and non-borated succinimide dispersant b) mixture of Ca and Mg detergents (phenate and sulfonate) c) phenolic, aminic, and molybdenum-based antioxidants d) foam inhibitor

[0074] For each example, a sulfur-containing wear agent and / or a polymeric dispersant was added to the baseline. The examples were then tested for antiwear capabilities using the Cummins® ISB Test. The results are shown below: Comp Ex 1 Comp Ex 2 Inv Ex A Inv Ex B Inv Ex C Sulfurized ester 03 - 03 03 03 Cummins® ISB Test

[0075] The Cummins® ISB test is an industry standard Diesel engine durability test using a Cummins® 5.9 L ISB engine. The test lasts 350 hr and consists of two stages: a 100 hr soot generation stage followed by a 250 hr cyclic stage to induce valve train wear.

[0076] Upon completion of the test cycle, the engine is dismantled and the Cam and Tappets are analyzed for wear. The Cam wear is reported in average cam scar width ACSW (µm), and the Tappet is reported as average tappet weight loss ATWL (mg). Pass / fail limits are 55 µm Cam wear and 100 mg Tappet weight loss.

[0077] It will be understood that various modifications may be made to the embodiments disclosed herein. Therefore, the above description should not be construed as limiting, but merely as exemplifications of embodiments of the invention. For example, the functions described above and implemented for operating are for illustration purposes only. Other arrangements and methods may be implemented by those skilled in the art without departing from the scope and spirit of this application. Moreover, those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto.

Claims

CLAIMS What is claimed is:

1. A lubricating oil composition comprising: oil of lubricating viscosity; sulfur-containing wear inhibitor; and polymeric dispersant.

2. The lubricating oil composition of claim 1, further comprising an oil soluble organomolybdenum compound in an amount to provide 50-100 ppm of molybdenum to the lubricating oil composition.

3. The lubricating oil composition of claim 1, wherein the polymeric dispersant is represented by the following generalized structure: A-B-C-D n wherein A is liquid olefinor alkyl amide, C is polyamine, alkyl amine, alkyl ether amine or alkyl hydroxyl amine, and D is 1-(arene-2-yloxy)propan-2-ol; and n is 1 to 15.

4. The lubricating oil composition of claim 1, wherein the sulfur-containing wear in inhibitor is a sulfurized ester or an ashless dithiocarbamate.

5. The lubricating oil composition of claim 4, wherein the sulfurized ester is sulfurized fatty ester or sulfurized fatty acid ester.

6. The lubricating oil composition of claim 1, wherein the liquid olefin copolymer has a number average molecular weight from about 1,500 to about 16,000.

7. The lubricating oil composition of claim 1, wherein the polymeric dispersant is the reaction product of: a liquid hydrocarbon polymer having a number average molecular weight (Mn) between about 1,500 and about 16,000; an ethylenically unsaturated acylating grafting agent; a polyamine having the following structure: A B H2N N H wherein A is C2-C10hydrocarbyl group, amino alkyl group, ether group, thioether group, or aromatic group; and B is C1-C10 hydrocarbyl group, alkyl hydroxyl group, ether group, thioether group, or aromatic group; and aryl glycidyl ether; or the reaction product of: a liquid hydrocarbon polymer having a number average molecular weight (Mn) between about 1,500 and about 16,000; an allyl or vinyl aminic grafting agent; and aryl glycidyl ether.

8. The lubricating oil composition of claim 7, wherein the ethylenically unsaturated acylating agent is acrylic acid, crotonic acid, methyacrylic acid, maleic acid, fumaric acid, itaconic acid,citraconic acid, mesaconic acid, glutaconic acid, chloromaleic acid, aconitic acid, methylcrotonic acid, sorbic acid or an anhydride thereof or an ester thereof.

9. The lubricating oil composition of claim 7, wherein the allyl or vinyl aminic grafting agent is 1-ethenylpiperazine, 1-(prop-1-en-2-yl)piperazine, 1-allylpiperazine, N-allylmethylamine, allylcyclohexylamine, N-allylaniline, N,2-dimethyl-2-propen-1-amine, N-ethyl-2- methylallylamine, or 1-(2-methylprop-2-en-1-yl)piperazine.

10. The lubricating oil composition of claim 7, wherein the polyamine is an aminoethyl piperazine.

11. The lubricating oil composition of claim 1, wherein the aryl glycidyl ether is a 2-naphthyl glycidyl ether.

12. A method for improving wear in an internal combustion engine, the method comprising lubricating the engine with a lubricating oil composition comprising: major amount of base oil; sulfur-containing wear inhibitor; and polymeric dispersant.

13. The method of claim 12, wherein the lubricating oil composition further comprises an oil soluble organomolybdenum compound in an amount to provide 50-100 ppm of molybdenum to the lubricating oil composition.

14. The method of claim 12, wherein the polymeric dispersant is represented by the following generalized structure: A-B-C-D n wherein A is liquid olefin copolymer, B is alkyl imide or alkyl amide, C is polyamine, alkyl amine, alkyl ether amine or alkyl hydroxyl amine, and D is 1-(arene-2-yloxy)propan-2-ol; and n is 1 to 15.

15. The method of claim 12, wherein the sulfur-containing wear in inhibitor is a sulfurized ester or an ashless dithiocarbamate.

16. The method of claim 15, wherein the sulfurized ester is sulfurized fatty ester or sulfurized fatty acid ester.

17. The method of claim 14, wherein the liquid olefin copolymer has a number average molecular weight from about 1,500 to about 16,000.

18. The method of 12, wherein the polymeric dispersant is the reaction product of: a liquid hydrocarbon polymer having a number average molecular weight (Mn) between about 1,500 and about 16,000; an ethylenically unsaturated acylating grafting agent;a polyamine having the following structure: A B H2N N H wherein A is C2-C10 hydrocarbyl group, amino alkyl group, ether group, thioether group, or aromatic group; and B is C1-C10hydrocarbyl group, alkyl hydroxyl group, ether group, thioether group, or aromatic group; and aryl glycidyl ether; or the reaction product of: a liquid hydrocarbon polymer having a number average molecular weight (Mn) between about 1,500 and about 16,000; an allyl or vinyl aminic grafting agent; and aryl glycidyl ether.

19. The method of claim 18, wherein the ethylenically unsaturated acylating agent is acrylic acid, crotonic acid, methyacrylic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, mesaconic acid, glutaconic acid, chloromaleic acid, aconitic acid, methylcrotonic acid, sorbic acid or an anhydride thereof or an ester thereof.

20. The method of claim 18, wherein the allyl or vinyl aminic grafting agent is 1- ethenylpiperazine, 1-(prop-1-en-2-yl)piperazine, 1-allylpiperazine, N-allylmethylamine, allylcyclohexylamine, N-allylaniline, N,2-dimethyl-2-propen-1-amine, N-ethyl-2- methylallylamine, or 1-(2-methylprop-2-en-1-yl)piperazine.

21. The method of claim 18, wherein the polyamine is an aminoethyl piperazine.

22. The method of claim 12, wherein the aryl glycidyl ether is a 2-naphthyl glycidyl ether.

Images