Lubricant composition

Abstract

The present invention relates to a lubricant composition comprising a polyalphaolefin type IV base oil component in an amount in the range of from 30 wt.% to 70 wt.%, based on the total weight of the lubricant composition, and an alkoxylated polytetrahydrofuran of formula (I) in an amount in the range of from 15 wt.% to 30 wt.%, based on the total weight of the lubricant composition. The invention also relates to a lubricant composition for use in an axle lubricant.

Description

Technical Field

[0001] This invention relates to a lubricant composition and an axle lubricant comprising the lubricant composition. The invention also relates to the use of the lubricant composition for reducing friction between moving surfaces; a method for enhancing the friction-modifying properties of the lubricant composition in the lubrication of mechanical devices; and a method for preparing the lubricant composition. Background Technology

[0002] Lubricant compositions typically need to have certain performance characteristics related to the performance of the lubricant composition itself and / or the equipment (e.g., vehicles) to which the lubricant composition will be used. Recently, market forces and government regulations have re-emphasized vehicle fuel efficiency and the reduction of greenhouse gas (GHG) emissions (e.g., CO2 emissions).

[0003] Conventional lubricants do not possess the desired kinematic viscosity, viscosity index, and pour point. Therefore, conventional lubricants have lower fuel efficiency.

[0004] Therefore, an object of the present invention is to provide a lubricant composition having a desired kinematic viscosity, high viscosity index, and low pour point. Another object of the present invention is to provide a lubricant composition that improves fuel efficiency and reduces CO2 emissions. Summary of the Invention

[0005] Surprisingly, it has been found that the lubricant composition of the invention claimed herein has the desired kinematic viscosity, high viscosity index and low pour point, which improves fuel efficiency and reduces CO2 emissions.

[0006] Therefore, on the one hand, the invention claimed herein relates to a lubricant composition comprising: a polyalphaolefin type IV base oil component in an amount ranging from 30 wt.% to 70 wt.% based on the total weight of the lubricant composition; and an alkoxylated polytetrahydrofuran having formula (I) in an amount ranging from 15 wt.% to 30 wt.% based on the total weight of the lubricant composition.

[0007] (I),

[0008] in

[0009] m is an integer in the range of ≥ 1 to ≤ 50.

[0010] m' is an integer in the range of ≥ 1 to ≤ 50.

[0011] (m+m') is an integer in the range of ≥ 1 to ≤ 90.

[0012] n is an integer in the range of ≥ 0 to ≤ 75.

[0013] n' is an integer in the range of ≥ 0 to ≤ 75.

[0014] p is an integer in the range of ≥ 0 to ≤ 75.

[0015] p' is an integer in the range of ≥ 0 to ≤ 75.

[0016] k is an integer in the range of ≥ 2 to ≤ 30.

[0017] R1 represents an unsubstituted straight-chain or branched alkyl residue having 6-28 carbon atoms.

[0018] R2 represents -CH2-CH3,

[0019] and

[0020] R3 represents a hydrogen atom or –CH3.

[0021] Among them, the cascaded distribution represented by k forms a block aggregation structure, and the cascaded distribution represented by p, p', n, n', m and m' forms a block aggregation structure or a random aggregation structure.

[0022] Among them, as measured according to ASTM D445, the kinematic viscosity of alkoxylated polytetrahydrofuran having formula (I) is in the range of 110 cSt to 125 cSt at 100°C and in the range of 1000 cSt to 1200 cSt at 40°C.

[0023] In another aspect, the present invention relates to an axle lubricant comprising a lubricant composition as mentioned herein.

[0024] In yet another aspect, the present invention relates to the use of a lubricant composition as defined herein for reducing friction between moving surfaces.

[0025] In another aspect, the present invention relates to a method for enhancing the frictional modification properties of a lubricating composition in the lubrication of a mechanical device, the method comprising formulating the lubricating composition with at least one alkoxylated polytetrahydrofuran having formula (I) as defined above.

[0026] In another aspect, the present invention relates to a method for preparing a lubricant composition as defined herein, wherein the method comprises mixing a polyalphaolefin type IV base oil component as defined herein and an alkoxylated polytetrahydrofuran having formula (I) as defined herein in a mixing container. Attached Figure Description

[0027] In the accompanying drawings, abbreviations LC 1, LC 2, and LC 3 represent lubricant composition 1, lubricant composition 2, and lubricant composition 3, respectively. Additionally, the abbreviation CL A represents a commercially available comparative lubricant A.

[0028] Figure 1a , 1b Figures 1 and 1c are bar graphs showing the fuel efficiency of the axle lubricant containing the lubricant composition of the present invention in urban, highway and (New European Driving Cycle) NEDC conditions.

[0029] X-axis: The X-axis represents the sample used in the fuel efficiency test; and

[0030] Y-axis: The Y-axis represents fuel savings as a percentage. Normalized relative to experiments using a commercially available metallocene-containing polyalphaolefin-based comparative lubricant A.

[0031] Figure 2a and 2b The gear cleanliness of lubricant composition 1 and lubricant composition 2 of the present invention are demonstrated respectively, and Figure 2c The gear cleanliness of commercially available comparative lubricant A was demonstrated. Detailed Implementation

[0032] Before describing the compositions and formulations of the present invention herein, it should be understood that the invention is not limited to the specific compositions and formulations described, as such compositions and formulations can certainly vary. It should also be understood that the terminology used herein is not intended to be limiting.

[0033] If a group is defined as including at least a certain number of embodiments, this means that it also includes a group preferably consisting only of those embodiments. Furthermore, the terms “first,” “second,” “third,” or “(a),” “(b),” “(c),” “(d),” etc., in the specification and claims are used to distinguish similar elements and are not necessarily used to describe a sequential or chronological order. It should be understood that such terms are interchangeable where appropriate, and the embodiments of the invention described herein can operate in orders other than those described or shown herein. If the terms “first,” “second,” “third,” or “(A),” “(B),” and “(C),” or “(a),” “(b),” “(c),” “(d),” “i,” “ii,” etc., relate to steps of a method or use or measurement, then there is no temporal or time interval continuity between these steps; that is, these steps may be performed simultaneously or there may be time intervals of seconds, minutes, hours, days, weeks, months, or even years between such steps, unless otherwise indicated in the application described above or below.

[0034] In the following paragraphs, different aspects of the invention are defined in more detail. Each aspect so defined may be combined with any one or more other aspects unless explicitly indicated otherwise. In particular, any feature indicated as preferred or advantageous may be combined with any one or more other features indicated as preferred or advantageous.

[0035] Throughout this specification, references to "an embodiment" or "preferred embodiment" mean that a particular feature, structure, or characteristic described in connection with that embodiment is included in at least one embodiment of the invention claimed herein. Therefore, the phrases "in one embodiment," "in a preferred embodiment," or "in another embodiment" appearing in different places throughout this specification do not necessarily all refer to the same embodiment, but may refer to the same embodiment. Furthermore, in one or more embodiments, particular features, structures, or characteristics may be combined in any suitable manner, as will be apparent to those skilled in the art from this disclosure. Moreover, although some embodiments described herein include certain features (but not others in other embodiments), combinations of features from different embodiments are intended to be within the scope of the invention and form different embodiments, as will be understood by those in the art. For example, in the appended claims, any of the claimed embodiments may be used in any combination.

[0036] Furthermore, the range defined throughout this specification also includes end values; that is, the range of 1 to 10 means that both 1 and 10 are included in the range.

[0037] First, certain terms are defined to facilitate understanding of this disclosure. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the embodiments of this invention pertain.

[0038] On one hand, the present invention relates to a lubricant composition comprising:

[0039] The polyalphaolefin type IV base oil component, in an amount ranging from 30 wt.% to 70 wt.% based on the total weight of the lubricant composition; and

[0040] An alkoxylated polytetrahydrofuran having formula (I), wherein the amount is in the range of 15 wt.% to 30 wt.% based on the total weight of the lubricant composition.

[0041] (I),

[0042] in

[0043] m is an integer in the range of ≥ 1 to ≤ 50.

[0044] m' is an integer in the range of ≥ 1 to ≤ 50.

[0045] (m+m') is an integer in the range of ≥ 1 to ≤ 90.

[0046] n is an integer in the range of ≥ 0 to ≤ 75.

[0047] n' is an integer in the range of ≥ 0 to ≤ 75.

[0048] p is an integer in the range of ≥ 0 to ≤ 75.

[0049] p' is an integer in the range of ≥ 0 to ≤ 75.

[0050] k is an integer in the range of ≥ 2 to ≤ 30.

[0051] R1 represents an unsubstituted straight-chain or branched alkyl residue having 6-28 carbon atoms.

[0052] R2 represents -CH2-CH3,

[0053] and

[0054] R3 represents a hydrogen atom or –CH3.

[0055] Among them, the cascaded distribution represented by k forms a block aggregation structure, and the cascaded distribution represented by p, p', n, n', m and m' forms a block aggregation structure or a random aggregation structure.

[0056] Among them, as measured according to ASTM D445, the kinematic viscosity of alkoxylated polytetrahydrofuran having formula (I) is in the range of 110 cSt to 125 cSt at 100°C and in the range of 1000 cSt to 1200 cSt at 40°C.

[0057] Polyalphaolefin Type IV base oil:

[0058] Polyalphaolefin (PAO) type IV base oils are synthetic viscosity fluids. Such synthetic viscosity fluids suitable for use in this invention include polyalphaolefins (PAOs) and synthetic oils derived from hydrocracking or hydroisomerization of Fischer-Tropsch high-boiling fractions, including waxes. These are two feedstocks composed of saturates with low levels of impurities consistent with their synthetic origins. Hydroisomerized Fischer-Tropsch waxes are highly suitable base feedstocks, containing saturated components characterized by isoparaffins (resulting from the isomerization of predominantly n-paraffins in Fischer-Tropsch waxes), which produce good blends with high viscosity indices and low pour points. Methods for hydroisomerizing Fischer-Tropsch waxes are described in U.S. Patents 5,362,378; 5,565,086; 5,246,566 and 5,135,638, and EP 710710, EP 321302 and EP 321304.

[0059] The polyalphaolefin type IV base oils applicable to this invention include hydrogenated polymers or oligomers of alpha olefins, including but not limited to C2 to C4 olefins. 32 α-olefins, wherein C8 to C9 16 Alpha-olefins (such as 1-octene, 1-decene, 1-dodecene, etc.) are preferred. Preferred polyalphaolefin type IV base oils are poly-1-octene, poly-1-decene, and poly-1-dodecene. More preferred polyalphaolefin type IV base oil is poly(1-decene).

[0060] The low-viscosity PAO fluid suitable for this invention can be conveniently prepared by polymerization of α-olefins in the presence of a polymerization catalyst, such as a Friedel-Crafts catalyst, including, for example, aluminum trichloride; boron trifluoride; or a complex of boron trifluoride with water, alcohols (such as ethanol, propanol, or butanol), carboxylic acids, or esters (such as ethyl acetate or ethyl propionate). For example, the methods disclosed in U.S. Patents 4,149,178 or 3,382,291 can be conveniently used herein. Other descriptions of PAO synthesis can be found in the following U.S. patents: 3,742,082 (Brennan); 3,769,363 (Brennan); 3,876,720 (Heilman); 4,239,930 (Allphin); 4,367,352 (Watts); 4,413,156 (Watts); 4,434,408 (Larkin); 4,910,355 (Shubkin); 4,956,122 (Watts); and 5,068,487 (Theriot).

[0061] High-viscosity PAO fluids can be prepared using the same methods as those used to prepare low-viscosity PAO fluids, as mentioned above.

[0062] The kinematic viscosity of polyalphaolefin type IV base oil is in the range of 3.8 cSt to 4.1 cSt at 100°C and in the range of 16 cSt to 18 cSt at 40°C.

[0063] In some embodiments, the kinematic viscosity of the polyalphaolefin type IV base oil at 40°C is 16 cSt to 20 cSt, 16 cSt to 22 cSt, 16 cSt to 24 cSt, 16 cSt to 26 cSt, 16 cSt to 28 cSt, or 16 cSt to 30 cSt.

[0064] In a preferred embodiment, the base oil is selected from polyalphaolefin type IV base oil.

[0065] Alkoxylated polytetrahydrofuran having formula (I):

[0066] Alkoxylated polytetrahydrofuran having formula (I) is

[0067] (I),

[0068] in

[0069] m is an integer in the range of ≥ 1 to ≤ 50.

[0070] m' is an integer in the range of ≥ 1 to ≤ 50.

[0071] (m+m') is an integer in the range of ≥ 1 to ≤ 90.

[0072] n is an integer in the range of ≥ 0 to ≤ 75.

[0073] n' is an integer in the range of ≥ 0 to ≤ 75.

[0074] p is an integer in the range of ≥ 0 to ≤ 75.

[0075] p' is an integer in the range of ≥ 0 to ≤ 75.

[0076] k is an integer in the range of ≥ 2 to ≤ 30.

[0077] R1 represents an unsubstituted straight-chain or branched alkyl residue having 6-28 carbon atoms.

[0078] R2 represents -CH2-CH3,

[0079] and

[0080] R3 represents a hydrogen atom or –CH3.

[0081] Among them, the cascaded body distribution represented by k forms a block aggregation structure, and the cascaded body distribution represented by p, p', n, n', m and m' forms a block aggregation structure or a random aggregation structure.

[0082] Preferably, k is an integer in the range of ≥ 3 to ≤ 25, more preferably, k is an integer in the range of ≥ 3 to ≤ 20, most preferably, k is in the range of ≥ 5 to ≤ 20, and most preferably, k is in the range of ≥ 6 to ≤ 16.

[0083] Preferably, m is an integer in the range of ≥ 1 to ≤ 25, and m' is an integer in the range of ≥ 1 to ≤ 25. More preferably, m is an integer in the range of ≥ 1 to ≤ 20, and m' is an integer in the range of ≥ 1 to ≤ 20.

[0084] Preferably, (m+m') is an integer in the range of ≥ 3 to ≤ 65, more preferably (m+m') is an integer in the range of ≥ 3 to ≤ 50, and even more preferably (m+m') is an integer in the range of ≥ 3 to ≤ 40.

[0085] Preferably, n is an integer in the range of ≥ 6 to ≤ 40, and n' is an integer in the range of ≥ 6 to ≤ 40. More preferably, n is an integer in the range of ≥ 8 to ≤ 35, and p' is an integer in the range of ≥ 8 to ≤ 35.

[0086] Preferably, (n+n') is an integer in the range of ≥ 10 to ≤ 80, more preferably (n+n') is an integer in the range of ≥ 15 to ≤ 70.

[0087] Preferably, p is an integer in the range of ≥ 5 to ≤ 25, and p' is an integer in the range of ≥ 5 to ≤ 25. More preferably, p is an integer in the range of ≥ 5 to ≤ 15, and p' is an integer in the range of ≥ 5 to ≤ 15.

[0088] Preferably, (p+p') is an integer in the range of ≥ 10 to ≤ 30, and more preferably, (p+p') is an integer in the range of ≥ 15 to ≤ 30.

[0089] Preferably, R 1 This refers to an unsubstituted straight-chain alkyl residue having 6-18 carbon atoms. More preferably, R 1 This indicates an unsubstituted straight-chain alkyl residue having 8-16 carbon atoms. Most preferably, R... 1 It represents an unsubstituted straight-chain alkyl residue having 8-12 carbon atoms.

[0090] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) is

[0091] (I),

[0092] in

[0093] m is an integer in the range of ≥ 1 to ≤ 30.

[0094] m' is an integer in the range of ≥ 1 to ≤ 30.

[0095] (m+m') is an integer in the range of ≥ 3 to ≤ 50.

[0096] n is an integer in the range of ≥ 3 to ≤ 45.

[0097] n' is an integer in the range of ≥ 3 to ≤ 45.

[0098] (n+n') is an integer in the range of ≥ 6 to ≤ 90.

[0099] p is an integer in the range of ≥ 0 to ≤ 75.

[0100] p' is an integer in the range of ≥ 0 to ≤ 75.

[0101] k is an integer in the range of ≥ 3 to ≤ 25.

[0102] R1 represents an unsubstituted straight-chain alkyl residue having 6-18 carbon atoms.

[0103] R2 represents -CH2-CH3,

[0104] and

[0105] R3 represents -CH3.

[0106] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) is

[0107] (I),

[0108] in

[0109] m is an integer in the range of ≥ 1 to ≤ 30.

[0110] m' is an integer in the range of ≥ 1 to ≤ 30.

[0111] (m+m') is an integer in the range of ≥ 3 to ≤ 50.

[0112] n is an integer in the range of ≥ 0 to ≤ 45.

[0113] n' is an integer in the range of ≥ 0 to ≤ 45.

[0114] p is an integer in the range of ≥ 3 to ≤ 45.

[0115] p' is an integer in the range of ≥ 3 to ≤ 45.

[0116] (p+p') is an integer in the range of ≥ 6 to ≤ 90.

[0117] k is an integer in the range of ≥ 3 to ≤ 25.

[0118] R1 represents an unsubstituted straight-chain alkyl residue having 6-18 carbon atoms.

[0119] R2 represents -CH2-CH3,

[0120] and

[0121] R3 stands for –CH3.

[0122] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) is formula (Ia).

[0123]

[0124] Formula (Ia)

[0125] Where n+n' = 35, m+m' = 20, and k = 14.

[0126] The alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of at least 110 cSt at 100°C.

[0127] In one embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of at least 111 cSt at 100°C.

[0128] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of at least 112 cSt at 100°C.

[0129] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of at least 113 cSt at 100°C.

[0130] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of at least 114 cSt at 100°C.

[0131] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of at least 115 cSt at 100°C.

[0132] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of at least 116 cSt at 100°C.

[0133] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of at least 117 cSt at 100°C.

[0134] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of at least 118 cSt at 100°C.

[0135] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of at least 119 cSt at 100°C.

[0136] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of at least 120 cSt at 100°C.

[0137] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of at least 121 cSt at 100°C.

[0138] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of at least 121.5 cSt at 100°C.

[0139] The kinematic viscosity of alkoxylated polytetrahydrofuran having formula (I) at 100°C is at most 125 cSt.

[0140] In one embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of up to 124 cSt at 100°C.

[0141] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of up to 123 cSt at 100°C.

[0142] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of up to 122 cSt at 100°C.

[0143] The alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of at least 1000 cSt at 40°C.

[0144] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of at least 10¹⁰ cSt at 40°C.

[0145] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of at least 1020 cSt at 40°C.

[0146] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of at least 1030 cSt at 40°C.

[0147] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of at least 1035 cSt at 40°C.

[0148] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of at least 1040 cSt at 40°C.

[0149] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of at least 1041 cSt at 40°C.

[0150] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of at least 1042 cSt at 40°C.

[0151] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of at least 1043 cSt at 40°C.

[0152] The kinematic viscosity of alkoxylated polytetrahydrofuran having formula (I) at 40°C is at most 1200 cSt.

[0153] In one embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of up to 1150 cSt at 40°C.

[0154] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of up to 1100 at 40°C.

[0155] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of up to 1090 at 40°C.

[0156] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of up to 1080 at 40°C.

[0157] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of up to 1070 at 40°C.

[0158] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of up to 1060 at 40°C.

[0159] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of up to 1050 at 40°C.

[0160] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of up to 1045 at 40°C.

[0161] The kinematic viscosity of alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 110 cSt to 125 cSt.

[0162] In one embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 111 cSt to 124 cSt.

[0163] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 112 cSt to 124 cSt.

[0164] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 113 cSt to 124 cSt.

[0165] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 114 cSt to 124 cSt.

[0166] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 115 cSt to 124 cSt.

[0167] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 116 cSt to 124 cSt.

[0168] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 117 cSt to 124 cSt.

[0169] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 118 cSt to 124 cSt.

[0170] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 119 cSt to 124 cSt.

[0171] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 120 cSt to 124 cSt.

[0172] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 114 cSt to 123 cSt.

[0173] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 115 cSt to 123 cSt.

[0174] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 116 cSt to 123 cSt.

[0175] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 117 cSt to 123 cSt.

[0176] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 118 cSt to 123 cSt.

[0177] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 119 cSt to 123 cSt.

[0178] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 120 cSt to 123 cSt.

[0179] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 115 cSt to 122 cSt.

[0180] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 116 cSt to 122 cSt.

[0181] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 117 cSt to 122 cSt.

[0182] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 118 cSt to 122 cSt.

[0183] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 119 cSt to 122 cSt.

[0184] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 120 cSt to 122 cSt.

[0185] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 100°C is in the range of 121 cSt to 122 cSt.

[0186] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of 121.9 cSt at 100°C.

[0187] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 40°C is in the range of 1000 cSt to 1200 cSt.

[0188] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 40°C is in the range of 1000 cSt to 1150 cSt.

[0189] In another embodiment, the kinematic viscosity of the alkoxylated polytetrahydrofuran having formula (I) at 40°C is in the range of 1000 cSt to 1100.

[0190] In another embodiment, the alkoxylated polytetrahydrofuran having formula (I) has a kinematic viscosity of 1043.6 cSt at 40°C.

[0191] Alkoxylated polytetrahydrofuran having formula (I) can be produced by reacting at least one polytetrahydrofuran block polymer with at least one C8-C 30 Epoxides, and optionally at least one epoxide selected from the group consisting of ethylene oxide, propylene oxide, and butane oxide, are obtained by reacting them in the presence of at least one catalyst. When using at least one epoxide selected from the group consisting of ethylene oxide, propylene oxide, and butane oxide, at least one C8-C... 30 Epoxides and at least one epoxide selected from the group consisting of ethylene oxide, propylene oxide, and butane oxide can be added in the form of a mixture of epoxides to obtain random copolymers, or added in portions, each portion containing a different epoxide, to obtain block copolymers. A method for preparing alkoxylated polytetrahydrofuran having formula (I) is described in EP 2 997 118 B1.

[0192] The kinematic viscosity of the lubricant composition at 100°C can be in the range of 11 cSt to 14 cSt, and at 40°C the kinematic viscosity can be in the range of 50 cSt to 110 cSt.

[0193] For the purposes of this disclosure, any reference to kinematic viscosity is as measured in accordance with ASTM D445.

[0194] The kinematic viscosity of the lubricant composition at 100°C is preferably in the range of 12 cSt to 14 cSt and at 40°C is in the range of 55 cSt to 100 cSt. More preferably, the kinematic viscosity of the lubricant composition at 100°C is in the range of 12.5 cSt to 13.6 cSt and at 40°C is in the range of 60 cSt to 90 cSt. Most preferably, the kinematic viscosity of the lubricant composition at 100°C is in the range of 12.5 cSt to 13.6 cSt and at 40°C is in the range of 60 cSt to 80 cSt.

[0195] Lubricant compositions may have a viscosity index in the range of 181 to 200 as measured according to ASTM D2270.

[0196] In one embodiment, the lubricant composition has a viscosity index in the range of 185 to 198 as measured according to ASTM D2270.

[0197] In one embodiment, the lubricant composition has a viscosity index in the range of 190 to 195 as measured according to ASTM D2270.

[0198] In one embodiment, the lubricant composition has a viscosity index in the range of 191 to 194 as measured according to ASTM D2270.

[0199] In one embodiment, the lubricant composition has a viscosity index in the range of 191 to 193 as measured according to ASTM D2270.

[0200] In one embodiment, the lubricant composition has a viscosity index in the range of 192 to 193 as measured according to ASTM D2270.

[0201] The lubricant composition may have a pour point of -50°C to -65°C.

[0202] For the purposes of this disclosure, any reference to pour point is as measured in accordance with ASTM D97.

[0203] In one embodiment, the lubricant composition has a pour point of -57°C to -60°C.

[0204] The lubricant composition can have a Brinell viscosity in the range of 20,000 cP to 35,000 cP at 40°C.

[0205] For the purposes of this disclosure, any reference to Brinell viscosity refers to Brinell viscosity as measured in accordance with ASTM D2983.

[0206] In one embodiment, the lubricant composition has a Brinell viscosity in the range of 23,000 cP to 33,000 cP at 40°C.

[0207] In one embodiment, the lubricant composition has a Brinell viscosity in the range of 24,000 cP to 31,000 cP at 40°C. The lubricant composition may further comprise additives selected from: gear oil additives, antioxidants, dispersants, defoamers, esters, polymer thickeners other than polytetrahydrofuran having formula (I), viscosity index improvers, corrosion inhibitors, detergents, demulsifiers, dyes, wear protection additives, extreme pressure additives, anti-wear additives, pour point depressants, friction modifiers, or mixtures of two or more thereof.

[0208] In one embodiment, the polymer thickener other than polytetrahydrofuran having formula (I) is selected from olefin copolymers (OCP), polymethyl acrylate (PMA), polyisobutylene (PIB), high-viscosity polyalphaolefin (PAO), or mixtures of two or more thereof.

[0209] In one embodiment, the gear oil additive is selected from Anglamol 6004M, a mixture of sulfurized isobutylene (sulfurized 2-methyl-1-propene) [CAS # 68511-50-2, ≥ 45 - ≤ 55 %w / w], distillates (petroleum), hydrotreated heavy paraffinic hydrocarbons [CAS # 64742-54-7, ≥ 25 - ≤ 35 %w / w], dipentyl hydrogen phosphate [CAS # 3138-42-9, ≥ 1 - < 3 %w / w], amines, C 12 -C 14 -Tetraalkyl [CAS # 68955-53-3, ≥ 1 - ≤ 3 %w / w], and (Z)-octadec-9-enamine [CAS # 112-90-3, ≥ 1 - < 2.5 %w / w], or mixtures thereof.

[0210] The gear oil may be contained in an amount ranging from 3 wt.% to 12 wt.% of the total weight of the lubricant composition.

[0211] In one embodiment, the gear oil is contained in an amount ranging from 5 wt.% to 12 wt.% based on the total weight of the lubricant composition.

[0212] In one embodiment, the gear oil is contained in an amount ranging from 7 wt.% to 12 wt.% based on the total weight of the lubricant composition.

[0213] In one embodiment, the gear oil is contained in an amount ranging from 8 wt.% to 10 wt.% based on the total weight of the lubricant composition.

[0214] The antioxidant may be selected from alkylated monophenols, alkylthiomethylphenols, hydroquinones and alkylated hydroquinones, hydroxylated thiodiphenyl ethers, alkylene bisphenols, O-, N- and S-benzyl compounds, hydroxybenzyl malonates, triazine compounds, aromatic hydroxybenzyl compounds, benzylphosphonates, acylaminophenols, esters of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid with mono- or polyols, esters of β-(5-tert-butyl-4-hydroxy-3-methylphenyl)propionic acid with mono- or polyols, amine antioxidants, aliphatic or aromatic phosphites, esters of thiodipropionic acid or thiodiacetic acid, salts of dithiocarbamate or dithiophosphate, 2-sulfurized aliphatic esters, sulfurized aliphatic and sulfurized olefins, or mixtures of two or more thereof.

[0215] In one embodiment, the antioxidant is an amine antioxidant.

[0216] Amine antioxidants may be selected from the reaction product of N-phenyl-aniline and 2,4,4-trimethylpentene (CAS #68411-46-1), N-phenyl-1,1,3,3-tetramethylbutylnaphthyl-1-amine, phenyl-1-naphthylamine, or mixtures thereof.

[0217] Antioxidants are typically included in an amount of 0 wt.% to 2 wt.% based on the total weight of the lubricant composition.

[0218] Dispersants can be derived from substrates including: succinimide dispersants, Mannich dispersants, ester-containing dispersants, condensation products of aliphatic hydrocarbon monocarboxylic acid acylating agents and amines or ammonia, alkylaminophenol dispersants, hydrocarbon-amine dispersants, polyether dispersants, polyetheramine dispersants, viscosity modifiers containing dispersant functions, or mixtures thereof.

[0219] In one embodiment, the dispersant is derived from a matrix including succinimide dispersants, ester-containing dispersants, or Mannich dispersants.

[0220] The dispersant is typically contained in an amount of 0 wt.% to 4 wt.% based on the total weight of the lubricant composition.

[0221] The defoamer may be selected from silicone-based defoamers, acrylate copolymer-based defoamers, ester-based defoamers, or mixtures thereof.

[0222] In one embodiment, the defoamer is an acrylate copolymer-based defoamer or an ester-based defoamer.

[0223] Defoamers are typically contained in amounts from 0 wt.% to 4 wt.% of the total weight of the lubricant composition.

[0224] The ester can be selected from diesters, polyol esters, trimethylolpropane esters, or mixtures thereof.

[0225] In one embodiment, the ester is an adipate ester.

[0226] In one embodiment, the adipic ester is dipropylheptanol diester of adipic acid.

[0227] Esters are typically contained in amounts from 0 wt.% to 25 wt.% of the total weight of the lubricant composition.

[0228] In one embodiment, the ester is contained in an amount of 0 wt.% to 15 wt.% based on the total weight of the lubricant composition.

[0229] Anti-wear additives may be selected from zinc dialkyl dithiophosphate (“ZDDP”), compounds containing sulfur and / or phosphorus and / or halogens (e.g., sulfurized olefins and vegetable oils), alkylated triphenyl phosphates, tricresyl phosphates, tricresyl phosphates, chlorinated paraffins, alkyl and aryl di- and trisulfides, amine salts of mono- and dialkyl phosphates, amine salts of methylphosphonic acids, diethanolaminomethyltoluyltriazole, bis(2-ethylhexyl)aminomethyltoluyltriazole, derivatives of 2,5-dimercapto-1,3,4-thiadiazole, ethyl 3-[(diisopropoxyphosphino)thio]propionate, triphenyl thiophosphate (triphenyl ... iphenylphosphorothioate), tri(alkylphenyl)thiophosphate and mixtures thereof (e.g., tri(isononylphenyl)thiophosphate), diphenylmononylphenylthiophosphate, isobutylphenyl diphenylthiophosphate, dodecylamine salt of 3-hydroxy-1,3-thiophosphane-3-oxide, 5,5,5-tris[isooctyl 2-acetate] trithiophosphate, derivatives of 2-mercaptobenzothiazole such as 1-[N,N-bis(2-ethylhexyl)aminomethyl]-2-mercapto-1H-1,3-benzothiazole, ethoxycarbonyl-5-octyl dithiocarbamate, ashless anti-wear additives containing phosphorus, or mixtures of two or more thereof.

[0230] In one embodiment, the anti-wear additive is zinc dialkyl-dithiophosphate.

[0231] Anti-wear additives are typically included in amounts ranging from 0.1 wt.% to 15 wt.% based on the total weight of the lubricant composition.

[0232] In one embodiment, the anti-wear additive is included in an amount ranging from 0.1 wt.% to 10 wt.% based on the total weight of the lubricant composition.

[0233] In one embodiment, the anti-wear additive is included in an amount ranging from 0.1 wt.% to 5 wt.% based on the total weight of the lubricant composition.

[0234] In one embodiment, the anti-wear additive is included in an amount ranging from 0.1 wt.% to 2 wt.% based on the total weight of the lubricant composition.

[0235] In one embodiment, the anti-wear additive is included in an amount ranging from 0.1 wt.% to 0.5 wt.% based on the total weight of the lubricant composition.

[0236] Pour point depressants may be selected from polymethyl acrylate and alkyl naphthalene derivatives, or mixtures thereof.

[0237] Pour point depressants are typically contained in amounts ranging from 0.001 wt.% to 1 wt.% based on the total weight of the lubricant composition.

[0238] Viscosity index improvers may be selected from polyacrylates, polymethacrylates, vinylpyrrolidone / methacrylate copolymers, polyvinylpyrrolidone, polybutene, olefin copolymers, styrene / acrylate copolymers, and polyethers, or mixtures of two or more thereof.

[0239] Viscosity index improvers are typically included in amounts ranging from 0.01 wt.% to 20 wt.% based on the total weight of the lubricant composition.

[0240] In one embodiment, the viscosity index improver is included in an amount ranging from 0.01 wt.% to 15 wt.% based on the total weight of the lubricant composition.

[0241] In one embodiment, a viscosity index improver is included in an amount ranging from 0.01 wt.% to 10 wt.% based on the total weight of the lubricant composition.

[0242] In one embodiment, the viscosity index improver is included in an amount ranging from 0.01 wt.% to 5 wt.% based on the total weight of the lubricant composition.

[0243] The lubricant composition of the present invention can be used in a variety of lubrication applications, and is particularly suitable as a lubricant for axles, transmissions (manual or automatic transmissions), transfer cases, power take-offs, transaxles, and bearings / wheels. That is, the lubricant composition can be used for both light-duty and heavy-duty axles.

[0244] Compared to conventional lubricants, this lubricant composition exhibits improved fuel efficiency. Furthermore, despite demonstrating improved fuel efficiency, the lubricant composition also possesses other properties such as good shear stability and oxidation / thermal stability.

[0245] The invention claimed herein provides one or more of the following advantages:

[0246] - The lubricant composition of the present invention increases fuel efficiency.

[0247] - The lubricant composition of the present invention also has other properties such as good shear stability and oxidation / thermal stability.

[0248] In another aspect, the present invention relates to an axle lubricant comprising a lubricant composition as defined herein.

[0249] In yet another aspect, the present invention relates to the use of a lubricant composition as defined herein for reducing friction between moving surfaces.

[0250] In another aspect, the present invention relates to a method for enhancing the frictional modification properties of a lubricant composition in the lubrication of a mechanical device, the method comprising formulating the lubricant composition with at least one alkoxylated polytetrahydrofuran having formula (I) as defined herein.

[0251] The term formulation typically refers to mixing ingredients / components until homogeneous to obtain a final product or composition. Mixing can be accomplished through turbulent mixing (such as by high-shear agitation) or laminar mixing.

[0252] In another aspect, the present invention relates to a method for preparing a lubricant composition as defined herein, wherein the method comprises mixing a polyalphaolefin type IV base oil component as defined herein and an alkoxylated polytetrahydrofuran having formula (I) as defined herein in a mixing container.

[0253] The polyalphaolefin type IV base oil component as defined herein and the alkoxylated polytetrahydrofuran having formula (I) as defined herein are mixed in a mixing vessel at a temperature of 35°C to about 50°C.

[0254] The lubricant composition may further comprise additives selected from: gear oil additives, antioxidants, dispersants, defoamers, esters, polymer thickeners other than polytetrahydrofuran having formula (I), viscosity index improvers, corrosion inhibitors, detergents, demulsifiers, dyes, wear protection additives, extreme pressure additives, anti-wear additives, pour point depressants, friction modifiers, or mixtures of two or more thereof.

[0255] In the mixing step, the additive is added together with the polyalphaolefin type IV base oil component as defined herein and the alkoxylated polytetrahydrofuran having formula (I) as defined herein.

[0256] The mixing container can be made of metal or glass. Mechanical stirring is provided to facilitate mixing.

[0257] Use sufficient mixing time to ensure a homogeneous product. Mixing time can range from 15 to 60 minutes.

[0258] In view of this disclosure, the methods for preparing the lubricant compositions of the present invention should be known and understood by those skilled in the art. Those skilled in the art will understand that such preparation methods are not limited to the present invention, and that one or more components may be modified based on the teachings herein or teachings known in the art.

[0259] The following examples illustrate the invention in more detail. Unless otherwise stated, all percentages and parts are by weight.

[0260] Example:

[0261] The ingredients of the preparations mentioned in Table 1 below:

[0262] Base oil 1: Poly(1-decene)[polyalphaolefin 4]

[0263] Base oil 2: [Polyalpha 6] Highly branched isoparaffinic polyalphaolefin

[0264] Gear oil additive 1: Anglamol 6004M [Gear oil additive package from Lubrizol]

[0265] Gear oil additive 2: A mixture of the following: sulfurized isobutylene (sulfurized 2-methyl-1-propene) [CAS # 68511-50-2, ≥ 45 - ≤ 55 %w / w], distillates (petroleum), hydrotreated heavy paraffinic hydrocarbons [CAS #64742-54-7, ≥ 25 - ≤ 35 %w / w], dipentyl hydrogen phosphate [CAS # 3138-42-9, ≥ 1 - < 3 %w / w], amines, C 12 -C 14 -Tetraalkyl [CAS # 68955-53-3, ≥ 1 - ≤ 3 %w / w], and (Z)-octadec-9-enamine [CAS # 112-90-3, ≥ 1 - < 2.5 %w / w]

[0266] Ester: Diester of adipic acid (dicarboxylic acid ester component)

[0267] Antioxidant 1: The reaction product of N-phenylaniline and 2,4,4-trimethylpentene (liquid octylated / butylated diphenylamine)

[0268] Antioxidant 2: N-Phenyl-1,1,3,3-Tetramethylbutylnaphthyl-1-amine (alkylated phenyl α-naphthylamine)

[0269] Antioxidant 3: Phenylacetyl-1-naphthylamine

[0270] Dispersant 1: Tetraethylenepentamine succinimide dispersant having polyisobutylene substituents formed from polyisobutylene having an average molecular weight of 1300 as determined by gel permeation chromatography.

[0271] Dispersant 2: HiTEC® 643D dispersant is 1300 MW N PIBSA (polyisobutylene succinic acid or anhydride) plus polyamines, wherein the dispersant is post-treated with maleic anhydride and boric acid.

[0272] Defoamer: Synative AC AMH-2 (non-silicone defoamer) is commercially available from BASF.

[0273] Thickener 1: Alkoxylated polytetrahydrofuran having formula (I) (thickener from BASF)

[0274]

[0275] Formula (Ia)

[0276] Where n + n' = 35, m + m' = 20, and k = 14

[0277] Thickener 2: Metallocene polyalphaolefin

[0278] The lubricant compositions within the scope of this disclosure are provided as Lubricant Composition 1, Lubricant Composition 2, and Lubricant Composition 3 in Table 1. Table 1 also provides a comparative lubricant as Comparative Lubricant A. Each individual component of each lubricant in Table 1 is provided as a weight percentage (wt.%) based on the total weight of the respective lubricant.

[0279] Table 1:

[0280]

[0281] The base oils are polyalphaolefin 4 [base oil 1] and polyalphaolefin 6 [base oil 2]. Polyalphaolefin 4 has a kinematic viscosity of 3.8 cSt at 100°C and 16.8 cSt at 40°C. Polyalphaolefin 6 has a kinematic viscosity of 5.9 cSt at 100°C and 30.8 cSt at 40°C.

[0282] The physical properties of lubricant compositions 1, 2, 3, and comparative lubricant A were measured and are provided in Table 1. Lubricant compositions 1, 2, and 3 were found to possess excellent low-temperature properties, shear stability, oxidation / thermal stability, and improved fuel savings.

[0283] Achieving all these properties with the appropriate kinematic viscosity is unpredictable. Therefore, the combination of viscosity index, pour point, and kinematic viscosity achieved by lubricant compositions 1-3 is unexpected.

[0284] As can be clearly seen from the pour point and viscosity index in Table 1, lubricant composition 1, lubricant composition 2 and lubricant composition 3 have excellent low-temperature properties when thickener 1 is used.

[0285] The shear stability of lubricant compositions 1, 2, and 3, as measured by the KRL shear test over an extended period (200 hours), was found to be comparable to that of the commercially available comparative lubricant A.

[0286] The fuel-saving benefits of lubricant composition 3 containing thickener 1 were compared with those of a commercially available contrast lubricant A containing metallocene polyalphaolefin. EPA 75 / 25 fuel economy and European NEDC cycle tests were conducted on a chassis dynamometer using a 2015 Dodge Ram truck (C 235 axle). Test results are shown in... Figure 1a , 1b In 1c.

[0287] from Figure 1a , 1b As can be clearly seen in 1c, the lubricant composition 3 with thickener 2 exhibits superior fuel saving benefits compared to the comparative lubricant A, which has a similar viscosity and is made of commercially available metallocene polyalphaolefin.

[0288] Oxidative and thermal stability were measured using the DKA oxidation test and oxidation / thermal test (L-60) for an extended period (200 hours). As clearly shown in Table 1, lubricant compositions 1, 2, and 3, containing thickener 1, provided performance comparable to that of the commercially available comparative lubricant A, which contains metallocene polyalphaolefins. Gear cleanliness results from the L-60 test are shown in Figure 2.

Claims

1. A lubricant composition comprising: The polyalphaolefin type IV base oil component, in an amount ranging from 30 wt.% to 70 wt.% based on the total weight of the lubricant composition; and An alkoxylated polytetrahydrofuran having formula (I), wherein the amount is in the range of 15 wt.% to 30 wt.% based on the total weight of the lubricant composition. (I)， in m is an integer in the range of ≥ 1 to ≤ 50. m' is an integer in the range of ≥ 1 to ≤ 50. (m+m') is an integer in the range of ≥ 1 to ≤ 90. n is an integer in the range of ≥ 0 to ≤ 75. n' is an integer in the range of ≥ 0 to ≤ 75. p is an integer in the range of ≥ 0 to ≤ 75. p' is an integer in the range of ≥ 0 to ≤ 75. k is an integer in the range of ≥ 2 to ≤ 30. R1 represents an unsubstituted straight-chain or branched alkyl residue having 6-28 carbon atoms. R2 represents -CH2-CH3, and R3 represents a hydrogen atom or –CH3. in, The cascaded distribution represented by k forms a block aggregation structure, and the cascaded distribution represented by p, p', n, n', m, and m' forms a block aggregation structure or a random aggregation structure. As measured according to ASTM D445, the kinematic viscosity of the lubricant composition is in the range of 11 cSt to 14 cSt at 100°C and in the range of 50 cSt to 110 cSt at 40°C.

2. The lubricant composition according to claim 1, wherein, m is an integer in the range of ≥ 1 to ≤ 30. m' is an integer in the range of ≥ 1 to ≤ 30. (m+m') is an integer in the range of ≥ 3 to ≤ 50. n is an integer in the range of ≥ 3 to ≤ 45. n' is an integer in the range of ≥ 3 to ≤ 45. (n+n') is an integer in the range of ≥ 6 to ≤ 90. p is an integer in the range of ≥ 0 to ≤ 75. p' is an integer in the range of ≥ 0 to ≤ 75. k is an integer in the range of ≥ 3 to ≤ 25. R1 represents an unsubstituted straight-chain alkyl residue having 6-18 carbon atoms. R2 represents -CH2-CH3, and R3 stands for –CH3.

3. The lubricant composition according to claim 1, wherein, m is an integer in the range of ≥ 1 to ≤ 30. m' is an integer in the range of ≥ 1 to ≤ 30. (m+m') is an integer in the range of ≥ 3 to ≤ 50. n is an integer in the range of ≥ 0 to ≤ 45. n' is an integer in the range of ≥ 0 to ≤ 45. p is an integer in the range of ≥ 3 to ≤ 45. p' is an integer in the range of ≥ 3 to ≤ 45. (p+p') is an integer in the range of ≥ 6 to ≤ 90. k is an integer in the range of ≥ 3 to ≤ 25. R1 represents an unsubstituted straight-chain alkyl residue having 6-18 carbon atoms. R2 represents -CH2-CH3, and R3 stands for –CH3.

4. The lubricant composition according to claim 1, wherein, The alkoxylated polytetrahydrofuran having formula (I) is formula (Ia). Formula (Ia) Where n+n' = 35, m+m' = 20, and k = 14.

5. The lubricant composition according to any one of claims 1 to 4, wherein, As measured according to ASTM D445, the kinematic viscosity of this polyalphaolefin type IV base oil is in the range of 3.8 cSt to 4.1 cSt at 100°C and in the range of 16 cSt to 18 cSt at 40°C.

6. The lubricant composition according to any one of claims 1 to 5, further comprising an additive selected from: gear oil additives, antioxidants, dispersants, defoamers, esters, polymer thickeners other than the polytetrahydrofuran having formula (I), viscosity index improvers, corrosion inhibitors, detergents, demulsifiers, dyes, wear protection additives, extreme pressure additives, anti-wear additives, pour point depressants, friction modifiers, or mixtures of two or more thereof.

7. The lubricant composition according to any one of claims 1 to 6, wherein, The lubricant composition has a viscosity index in the range of 181 to 200 as measured according to ASTM D2270.

8. The lubricant composition according to any one of claims 1 to 7, wherein, This lubricant composition has a pour point of -50°C to -65°C as measured according to ASTM D97.

9. The lubricant composition according to any one of claims 1 to 8, wherein, This lubricant composition has a pour point of -57°C to -60°C as measured according to ASTM D97.

10. An axle lubricant comprising the lubricant composition according to claims 1 to 9.

11. Use of the lubricant composition according to any one of claims 1 to 9 for reducing friction between moving surfaces.

12. A method for enhancing the frictional modification properties of a lubricating composition in the lubrication of a mechanical device, the method comprising formulating the lubricating composition with at least one alkoxylated polytetrahydrofuran having formula (I) as defined in any one of claims 1 to 4.

13. A method for preparing a lubricant composition according to any one of claims 1 to 9, wherein, The method comprises mixing a polyalphaolefin type IV base oil component as defined in claims 1 and 6 and an alkoxylated polytetrahydrofuran having formula (I) as defined in any one of claims 1 to 4 in a mixing container.

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