Synthetic fluids with improved biodegradability.

Abstract

To provide a lubricant composition having high biodegradability, low pour point, high oxidative stability, and low sludge forming tendencies.SOLUTION: Disclosed lubricant composition has a 100°C viscosity of about 4 cSt, 250°C Noack volatility loss of under 19%, 200°C Noack volatility loss of under 4%, a viscosity index of over 125, a pour point of under -35°C, and a Cold Cranking Simulator viscosity at -35°C of under 1,500 cP.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to low viscosity polyalphaolefin (PAO) compositions characterized by high biodegradability, low pour point, high oxidative stability, and low sludge formation tendency. More specifically, the present invention provides PAO compositions having improved kinematic viscosities at 100°C and improved processes for the selective production of the improved compositions. [Background technology]

[0002] Oligomers of alpha olefins (also known as linear alpha olefins or vinyl olefins), processes for their production, and their use in formulating synthetic and semi-synthetic lubricants are known in the art. Some representative methods for making PAO oligomers include the following U.S. Patent Nos. 3,682,823; 3,763,244; 3,769,363; 3,780,123; 3,798,284; 3,884,988; 3,097,924; 3,997,621; 4,045,507; and 4,045,508.

[0003] Traditionally, alpha olefin oligomers found to be useful as synthetic base fluids are primarily prepared from linear terminal olefins containing approximately 8 to 14 carbon atoms, such as 1-octene, 1-decene, 1-dodecene, 1-tetradecene, and mixtures thereof. One of the most widely used alpha olefins is 1-decene, which can be used alone or in mixtures with other alpha olefins. When linear alpha olefins are used, the oligomer product contains mixtures containing varying amounts of dimers, trimers, tetramers, pentamers, and higher oligomers. The oligomer product is typically hydrogenated to improve thermal and oxidative stability and must be further fractionated to be useful in specific applications. Such hydrogenated and fractionated oligomer products are known for their excellent performance, long service life, low volatility, low pour point, and high viscosity index. Desirably, base fluid compositions would have improved properties, including biodegradability, and require simpler manufacturing processes. In conventional polyalphaolefin processes, the kinematic viscosity of the product can be adjusted by either removing or adding higher or lower oligomers to produce compositions with the viscosity desired for a particular application. Viscosities in the range of 2 to 150 centistokes (cSt) at 100°C are generally required, with preferred viscosities being in the range of 2 to 10 cSt. These low viscosity fluids are particularly useful in energy conservation applications such as engine lubricants to minimize friction and thereby improve fuel economy. When used either alone or in blends with mineral oils, they can result in lubricants with viscosities that qualify as, for example, SAE 0W-XX or SAE 5W-XX crankcase oils.

[0004] There is an especially large market for synthetic lubricant base stocks with kinematic viscosities of 2.5 to 4.5 cSt at 100°C, especially when this property is combined with low Noack volatility, low pour point, useful low temperature viscosity, and high viscosity index. 4 cSt PAOs can be made by decene oligomerization of 1-decene using a Friedel-Crafts catalyst such as BF3 with a promoter such as an alcohol. However, 1-decene is a by-product made with a wide range of other alpha olefins and is therefore in limited supply. It would be desirable to provide more flexibility in making synthetic base stocks using a wider range of alpha olefins while producing oligomers with substantially similar viscosity characteristics. An additional problem associated with making oligomeric oils from 1-decene or other alpha olefins is that the oligomeric product mix must usually be fractionated into different portions to obtain an oil of a given viscosity (e.g., 2, 4, 6, or 8 cSt at 100°C). The above commercial production processes result in an oligomeric product mix that, when fractionated, produces relative amounts of each viscosity product corresponding to market demand. As a result, excess amounts of one product are often produced to obtain the required amount of the other.

[0005] Moreover, while commercially available PAO products offer a useful balance of properties, applications requiring a narrow range of specific viscosities, e.g., 4 cSt materials (primarily decene trimer or C 30 ) must be distilled from the complex oligomer mixture. The distillation process, in turn, creates heavier by-products. For this reason, decene-derived PAOs with viscosities between 4 and 5.5 cSt must be post-blended from 4 cSt PAOs and higher viscosity PAOs.

[0006] Therefore, due to limited decene supplies, it would be desirable to produce 2.5-4.5 cSt compositions from feedstocks other than decene that have similar or better properties than decene base oils. It would also be desirable to produce such 2.5-4.5 cSt compositions selectively and without any by-products or the need for post-blending. Polyalphaolefins derived from other linear alpha olefins are known in the art. Polyalphaolefins derived from pure tetradecene are known to have particularly high pour point and -40°C viscosity characteristics.

[0007] Polyalphaolefin trimers prepared under the same conditions have demonstrated that viscosity index increases with increasing chain length of the starting alphaolefin. Conversely, volatility decreases with increasing chain length of the starting alphaolefin. Given that high viscosity index and low volatility are desirable properties for lubricants, there has long been a need for methods to utilize longer carbon number alphaolefins in the production of polyalphaolefins.

[0008] Unfortunately, it is understood that the pour point and low temperature viscosity also increase with increasing chain length of the starting alpha olefin. For example, decene (C 10 ) polyalphaolefin terpolymer is fluid down to temperatures below -65 degrees Celsius. 14 ) Polyalphaolefin trimer, in contrast, is a frozen solid at -20 degrees Celsius according to one source ("Synthetic Lubricant Base Stock Processes and Products" by Margaret M. Wu, Suzzy C. Ho, and T. Rig Forbus). [Table 1] Shubkin has shown that even tetradecene oligomers containing significant amounts of tetradecene dimers result in compositions that are frozen solid at -18 to -20 degrees Celsius (Shubkin et al., "Tailor Making Polyalphaolefins" in Engine oils and Automotive Lubrication; ed. Wilfred Bartz, 1993, pub. Verlag). [Table 2]

[0009] It is known that for a base stock to be suitable for use in an SAE 5W motor oil, the oil must be fluid at -30 degrees Celsius to meet cold cranking requirements. The requirements for SAE 0W oil are even more stringent - the base stock must be fluid at -35 degrees Celsius to meet cold cranking requirements. Many industrial oils also have a -40 degree Celsius Brookfield viscosity requirement which will preclude the use of any base stocks that have poor low temperature fluidity.

[0010] Because prior art methods for producing PAOs suitable for use as base fluid compositions suffer from many deficiencies, there remains a need for improved PAO compositions and improved methods for making said polyalphaolefins. The present invention addresses these needs by providing a single-step process for producing low viscosity polyalphaolefins and compositions characterized by low pour points, good low temperature viscosity, high viscosity index, and good biodegradability. Summary of the Invention

[0011] The present invention claims low viscosity polyalphaolefin (PAO) compositions characterized by high biodegradability, low pour point, high oxidative stability, and low sludge formation tendency, and more particularly provides PAO compositions having a kinematic viscosity at 100°C in the range of about 2.5 to 4.5 cSt. The present invention also claims an improved process for the selective production of the aforementioned compositions by oligomerization of 1-tetradecene in the absence or presence of a second comonomer using a catalyst system comprising BF3 and an alcohol alkoxylate promoter. The process of the present invention provides a C 28 The claimed invention also relates to compositions useful in ultra-low viscosity engine oil applications (e.g., 0W-16), blended with Group III oils and GTLs that improve the low temperature properties of such formulations.

[0012] The claimed invention further includes a process for producing a highly biodegradable low-viscosity oil useful as a lubricant in environmentally sensitive applications, such as marine lubrication. The properties of the low-viscosity oil can be further enhanced by the use of conventional lubricant additives in a total amount of up to about 35 weight percent, preferably 0.1 to 30 weight percent. Such additives include, for example, dispersants, antioxidants, antiwear agents, antifoam agents, corrosion inhibitors, detergents, seal swell agents, and viscosity index improvers. These types of additives are well known in the art. Such additives may themselves be substantially biodegradable, although this is not a requirement.

[0013] Preferred embodiments of the aforementioned low-viscosity oil additives include zinc dialkyl-dithiophosphates, calcium arylsulfonates, overbased calcium arylsulfonates, barium phenates, reaction products of phosphorus pentasulfide and high molecular weight olefinic terpenes neutralized with barium oxide, hindered alkylphenols, methylene-bis-dialkylphenols, dibutyltin sulfide, dibutyl hydrogen phosphate, tricresyl phosphate, high molecular weight alkyl succinimides of ethylene-polyamines such as tetraethylene-polyamines, sulfur-bridged alkylphenols, sulfurized fatty acid esters and amides, silicones, and dialkyl esters. Unique combinations of such additives, "additive packages," tailored to specific base oils and applications are commercially available from several sources, including Afton Corporation, Lubrizol, or Infineum. Viscosity index (VI) improvers are available separately. The fluids of the present invention can be used with other base oils or additive oils. These base oils include C6-C 10 These include, but are not limited to, 1-olefin PAOs, mineral oils, or synthetic esters.

[0014] The overall biodegradability of formulations containing the fluids of the present invention is dependent on the overall lubricant blend, including the functional fluid or lubricant additive. Finally, the present invention claims the use of the subject polyalphaolefin fluids as base fluids in engine oils or marine lubricants of SAE 0W-8, SAE 0W-12, and SAE 0W-16 viscosity grades, alone or in combination with other lubricating oils (e.g., Group I, Group II, Group III, Group III+ mineral oils, GTL). DETAILED DESCRIPTION OF THE INVENTION

[0015] A polyalphaolefin fluid is claimed comprising oligomers prepared from the oligomerization of one or more alphaolefin components. In a preferred embodiment, the alphaolefin component comprises C14 a first olefin comprising an alpha olefin; and a C 12 -C 20 The second olefin has an even number of carbon atoms, and the ... 10 -C 18 or R′ and R″ are each independently different and both are hydrocarbyl, and the sum of R′ and R″ is C 10 -C 18 is. R' □ R''□C=CH2

[0016] The fluids of the present invention contain a boron trifluoride catalyst and an alcohol alkoxylate (R a -O-CHR b -CHR c -O-) n -H cocatalyst or "promoter" produced by cationic oligomerization of one or more of the olefins or olefins described above, followed by hydrogenation, at 100°C from about 2.5 to about 4.6 mm 2This produces a fluid with a kinematic viscosity of 1000 kJ / s and at least approximately 50 percent biodegradability as determined by the OECD 301B test. The OECD 301B biodegradation test (modified Sturm test) is recommended by the OECD Expert Group on Degradation to determine the biodegradability of organic chemicals in aqueous environments. The test is suitable for soluble and insoluble nonvolatile organic compounds and measures the amount of CO2 evolved, thereby providing an indication of "complete" biodegradation. The test material is introduced into a flask containing a mineral substrate and a bacterial inoculum. After ultrasonic vibration, the flask contents are aerated with CO2-free air. A control (e.g., sodium benzoate 20 mg C / L) is run simultaneously. The EPA recommends the use of freshly distilled aniline as a control substance. Any CO2 released is absorbed in a flask containing a solution of barium hydroxide, and its concentration is periodically determined by titration with hydrochloric acid. Biodegradation is expressed as a percentage of the total amount of CO2 evolved during the test relative to the theoretical CO2 that the test material could produce (corrected for the control). Tests usually last 28 days but may be terminated earlier, i.e., as soon as the biodegradation curve reaches a plateau for at least three measurements. Alternatively, if the curve indicates that biodegradation begins within the first 28 days but has not reached a plateau by the 28th day, the test can be extended beyond 28 days.

[0017] Alcohol alkoxylate (R a -O-CHR b -CHR c -O-) n -H, R a is a hydrocarbyl containing 1 to 24 carbons, including mixtures thereof; R b and R c are each independently hydrogen, methyl, or ethyl, and n is an average of 1 to 15. Preferred alcohol alkoxylate promoters include 2-methoxyethanol and 1-methoxy-2-propanol. A process for making a polyalphaolefin fluid from a first olefin comprising 1-tetradecene and 0 to 70 weight percent of a second olefin (R'R''C=CH2 as defined above), comprising reacting the olefin with boron trifluoride and an alcohol alkoxylate (R'R''C=CH2 as defined above) to produce an oligomeric reaction product containing at least about 70 weight percent dimer (or co-dimer) of said olefin monomer and having a dimer to trimer ratio of greater than about 1. a -O-CHR b -CHR c -O-) n -H). In a preferred embodiment, the 1-tetradecene of this embodiment comprises greater than 90% polyalphaolefin mixture.

[0018] In a preferred embodiment of the present invention, the second olefin comprises a dimer of a C8 alpha olefin, i.e., 2-n-hexyl-1-decene, prepared by contacting a C8 alpha olefin with an aluminum alkyl catalyst, such as triethylaluminum, as described in U.S. Patent No. 8,455,416, the disclosure of which is incorporated herein by reference. Alternatively, the dimer is prepared by contacting a C8 alpha olefin with a Group IVB metallocene catalyst activated with an organoaluminum compound and a hydrocarbyl boron compound, as described in U.S. Patent No. 6,548,723, the disclosure of which is incorporated herein by reference. The polyalphaolefin fluids of the present invention are prepared without by-products and without post-blending or overhead distillation of any components other than unreacted monomer.

[0019] The polyalphaolefin fluids of the present invention are suitable for use as base fluids in engine oils in SAE 0W-8, 0W-12, and SAE 0W-16 viscosity grades or marine lubricants meeting Vessel General Permit (VGP) requirements, alone or in combination with other petroleum-derived mineral lubricating oils (i.e., Group I, Group II, Group III, Group III+ mineral oils), synthetic oils derived from methane using Fischer-Tropsch catalysts (i.e., for example, Gas to Liquids fluids or Coal to Liquids fluids).

[0020] A preferred embodiment of the present invention provides a hydrogenated composition having a viscosity at 100° C. of about 4 cSt, a Noack 250° C. volatility loss of less than 19% and a Noack 200° C. volatility of less than 4%, a viscosity index greater than 125, a pour point less than −35° C., and a Cold Crank Simulator viscosity at −35° C. of less than 1,500 cP. A more preferred embodiment of the present invention provides a hydrogenated composition having a viscosity at 100° C. of about 4 cSt, a Noack 250° C. volatility loss of 13.9%, a pour point of about −59° C., and a Cold Crank Simulator viscosity at −35° C. of less than 1,700 cP. Another embodiment of the present invention provides a hydrogenated composition having a viscosity at 100°C of about 3.4 cSt, a Noack volatility at 200°C of 4%, a pour point of about -50°C, and a Brookfield viscosity at -40°C of less than 1,750 cP.

[0021] The polyalphaolefins of the present invention combine excellent low temperature characteristics with exceptional high temperature stability, as well as significant biodegradability. These polyalphaolefins are suitable for use as base fluids for a wide variety of environmentally friendly lubricants, either as the sole base fluid or in conjunction with vegetable or synthetic esters, other polyalphaolefins (PAOs), mineral oils, gas-to-liquid fluids, additives, etc.

[0022] Environmentally friendly oils in which the fluids of the present invention may be advantageously used include, but are not limited to: 2-cycle engine oil Air Tool Lubricant Chain and Cable Lubricant elevator lubricant Concrete and Asphalt Release Agent Railway Grease Multipurpose grease Hydraulic oil for stationary or mobile equipment machine oil Metal casting mold release agent Rock drill oil Transformer and transmission line coolant Slideway Lubricant Total Loss Lubricant Wire rope lubricant Stern tube lubricant forestry oil

[0023] Oils that are not necessarily considered environmentally friendly, but with which the fluids of the present invention may also be used to advantage, include, but are not limited to: Industrial Gear Lubricants Transportation Gear Lubricants Compressor oil Gasoline engine crankcase lubricant Diesel engine crankcase lubricant transmission oil Turbine oil In particular, the polyalphaolefins of the present invention meet the viscosity requirements defined by the Society of Automotive Engineers (SAE) for use as base fluids in 0W-8, 0W-12, and 0W-16 engine oils.

[0024] Furthermore, the polyalphaolefins of the present invention can be used in any lubricant type that finds use in plant esters, estolides, or natural / synthetic ester derivatives. Marine stern tube lubricants, open gear oils, wire rope oils, forestry oils, and hydraulic oils are all applications that can benefit from the addition of the polyalphaolefins of the present invention. This class of oils can be made significantly biodegradable with the appropriate selection of additives and thickeners. One preferred embodiment of a fluid formulated in accordance with the foregoing comprises a mixture of a) 1 to 97% of the polyalphaolefin fluid of the present invention, b) 0 to 60% of a fluid selected from the group consisting of synthetic esters, synthetic hydrocarbon fluids, mineral oils, natural esters, or hydrocarbon oils derived from natural and petroleum-sourced sources, and c) 0.1 to 30% of an additive, such as a dispersant, antioxidant, antiwear agent, antifoam agent, corrosion inhibitor, detergent, seal swell agent, viscosity improver, and combinations thereof, such that the overall composition meets the viscosity requirements of an SAE 0W-XX grade (where XX is 16 or less).

[0025] Another preferred embodiment of the functional fluid or lubricant composition comprises a mixture comprising a) 1 to 97% of the polyalphaolefin fluid of the present invention in admixture with b) 0 to 60% of a fluid selected from the group consisting of synthetic esters, synthetic hydrocarbon fluids, mineral oils, natural esters, or hydrocarbon oils derived from natural and petroleum-sourced sources, and c) 0.1 to 70% of an additive, such as a dispersant, antioxidant, antiwear agent, antifoam agent, corrosion inhibitor, detergent, seal swell agent, viscosity improver, such that the overall composition exhibits at least 50% biodegradability as determined by the CEC L-33 A94 test (or equivalent), wherein the composition may be intentionally or accidentally released into the environment.

[0026] In another preferred embodiment, a functional fluid or lubricant composition is provided, comprising: a) 1 to 98% of the polyalphaolefin fluid of the present invention in admixture with b) 0 to 60% of one or more components selected from natural or synthetic esters, natural or synthetic hydrocarbon fluids, or hydrocarbon oils derived from natural and petroleum-sourced sources; and c) 0.1 to 70% of additives, such as dispersants, antioxidants, antiwear agents, antifoam agents, corrosion inhibitors, detergents, seal swell agents, and viscosity improvers. This embodiment may be particularly preferred for applications involving the operation of chainsaws, outboard motors, agricultural equipment, earthmoving machinery, or marine or submarine fluids. For marine-specific applications, the overall composition can be tailored to meet the requirements of the EPA Marine General Permit. [Example]

[0027] 1-Tetradecene (C) commercially produced from INEOS Oligomers 14 ) was used as received; 1-tetradecene from other suppliers may be substituted. All process steps can be carried out in batch, semi-batch, or continuous mode. The reaction can be run in continuous mode using two to five continuous stirred tank reactors (CSTs) in series or parallel or a combination thereof.

[0028] Comparative Example 1: A 1-gallon Parr reactor equipped with jacketed heating and internal cooling was charged with 1,200 g of 1-tetradecene and 3.0 g of 1-butanol (1-BuOH) and heated to 50°C with stirring. Boron trifluoride (BF3) was introduced as a gas and adjusted to a steady-state pressure of 40 psig. The reaction was stirred for 90 minutes. The reaction mixture was quenched with 400 mL of 8% NaOH and then washed with distilled water. Residual unreacted monomer was removed as a volatile overhead fraction under reduced pressure (220°C, 0.1 mmHg) to isolate 837.1 g of a clear fluid as a bottoms fraction, which was hydrogenated under a set of standard hydrogenation conditions (170°C, 400 psi hydrogen, using Ni on Kieselguhr catalyst) to yield a synthetic base stock with the following properties: [Table 3]

[0029] Invention Example 2: A one-gallon Parr reactor equipped with jacketed heating and internal cooling was charged with 1,400 g of 1-tetradecene and 4.2 g of 1-methoxy-2-propanol (1-MOP) and heated to 50°C with stirring. Boron trifluoride (BF3) was introduced as a gas and adjusted to a steady-state pressure of 20 psig. The reaction was stirred for 120 minutes. The reaction mixture was quenched with 400 mL of 8% NaOH and then washed with distilled water. Residual unreacted monomer was removed as a volatile overhead fraction under reduced pressure (220°C, 0.1 mmHg) to isolate 1,063.1 g of a clear fluid as a bottoms fraction, which was hydrogenated under a set of standard hydrogenation conditions (170°C, 400 psi hydrogen, using Ni on Kieselguhr catalyst) to yield a synthetic base stock of the present invention having the following properties:

[0030] [Table 4]

[0031] The above table shows that once the residual unreacted monomer is removed, the resulting PAO has the viscosity property balance of the present invention, which is a straight run, single-stage 4 cSt fluid produced without further distillation. It also has a high viscosity index, good Noack volatility, and significantly improved pour point characteristics compared to conventional C14 oligomers made with BF3 catalyst systems promoted with conventional alcohols such as 1-butanol (1-BuOH): [Table 5]

[0032] The oligomeric composition of the PAO of the present invention from Example 2 by GC showed the following composition: C 28 (dimer): 88.0 area% C42+ (trimer or more): 12.0 area% Invention Example 3: The procedure set out in Example 2 was carried out on a pilot scale. The product had the following properties: [Table 6]

[0033] Invention Example 4: A 1-gallon Parr reactor equipped with jacketed heating and internal cooling was charged with 1,200 g of 1-tetradecene and 3.1 g of 2-methoxyethanol (2-MOE) and heated to 50°C with stirring. Boron trifluoride (BF3) was introduced as a gas and adjusted to a steady-state pressure of 40 psig. The reaction was stirred for 90 minutes. The reaction mixture was quenched with 400 mL of 8% NaOH and then washed with distilled water. Residual unreacted monomer was removed as a volatile overhead fraction under reduced pressure (220°C, 0.1 mmHg) to isolate 737.3 g of a clear fluid as a bottoms fraction, which was hydrogenated under a set of standard hydrogenation conditions (170°C, 400 psi hydrogen, using Ni on Kieselguhr catalyst) to yield a synthetic base stock with the following properties:

[0034] [Table 7]

[0035] Invention Example 5: A 1-gallon Parr reactor equipped with jacketed heating and internal cooling was charged with 476 g of 1-tetradecene, 924 g of 1-dodecene, and 4.2 g of 1-methoxy-2-propanol (1-MOP) and heated to 50°C with stirring. Boron trifluoride (BF3) was introduced as a gas and adjusted to a steady-state pressure of 20 psig. The reaction was stirred for 120 minutes. The reaction mixture was quenched with 400 mL of 8% NaOH and then washed with distilled water. Removal of the remaining unreacted monomer fraction as a volatile overhead fraction under reduced pressure (220°C, 0.1 mmHg) resulted in the isolation of 993.9 g of a clear fluid as a bottoms fraction, which was hydrogenated under a set of standard hydrogenation conditions (170°C, 400 psi hydrogen, using Ni on Kieselguhr catalyst) to yield a synthetic base stock with the following properties:

[0036] [Table 8]

[0037] Invention Example 6: Example 4 was repeated using 2-methoxyethanol (2-MOE) as the cocatalyst. The product had the properties shown in Table 6. [Table 9]

[0038] Invention Example 7: A 1-gallon Parr reactor equipped with jacketed heating and internal cooling was charged with 515.0 g of 1-tetradecene, 885.0 g of 2-n-hexyl-1-decene (a dimerization product of 1-octene according to U.S. Pat. No. 8,455,416), and 1.4 g of 1-methoxy-2-propanol (1-MOP). The mixture was heated to 30°C with stirring. Boron trifluoride (BF3) was introduced as a gas, which was adjusted to a steady-state pressure of 20 psig. The reaction was stirred for 90 minutes. The reaction mixture was quenched with 400 mL of 8% NaOH and then washed with distilled water. Residual unreacted monomer was removed as a volatile overhead fraction under reduced pressure (220°C, 0.1 mmHg) to isolate 1,162.0 g of a clear fluid as a bottoms fraction, which was hydrogenated under a set of standard hydrogenation conditions (170°C, 400 psi hydrogen, Ni on Kieselguhr catalyst) to give a synthetic base stock with the following properties:

[0039] [Table 10]

[0040] Biodegradability of the polyalphaolefins of the present invention Substances are considered to be biodegradable if they can be efficiently broken down by microorganisms. There are several procedures that can be used, and have been used, to assess biodegradability. One test protocol that is approved by the OECD and is well suited to studying paraffinic hydrocarbons is the 301B "Ready Biodegradability" test (also known as the Forward Sturm test).

[0041] Example 8 In the OECD 301B test, test samples are exposed to activated sewage sludge and culture medium in sealed tubes maintained at 21°C. Degradation of the test material is assessed by measuring the carbon dioxide produced over a 28-day period. A control solution containing sewage microorganisms and a standard material is also run. Using this test, the polyalphaolefin of Example 7 achieved 100% degradation after 28 days and 60% degradation after 10 days.

[0042] In contrast, the isoviscous 1-decene derived PAO achieved only 28% degradation after 28 days. Further comparisons can be seen in Table 8 below: [Table 11]

[0043] Example 9 The product of Inventive Example 3, a polyalphaolefin derived entirely from 1-tetradecene, achieved 54% degradation in the OECD 301B biodegradation test after 28 days. Example 10 The product of Inventive Example 5, a polyalphaolefin derived from 1-tetradecene and 1-dodecene, achieved 87.3% degradation in the OECD 301B biodegradation test after 28 days.

[0044] Formulated oils containing the present invention The fluids of the present invention can be used in formulated lubricant products that are not designed to be substantially biodegradable but are capable of accidental release into the environment, such as crankcase lubricants, industrial and automotive gear oils, transmission oils, and the like. The unique balance of biodegradability, low temperature properties, and thermo-oxidative stability makes the fluids of the present invention particularly well suited for use in lubricants where release into the environment may be expected, either accidentally (e.g., marine lubricants) or intentionally (e.g., forestry lubricants). In these lubricant classes, the remarkable biodegradability of the fluids of the present invention is an advantage.

[0045] In lubricant products formulated to be substantially biodegradable, such as hydraulic fluids, paper mill oils, chainsaw lubricants, outboard motor lubricants, turbine oils, compressor oils, and greases, the fluids of the present invention can be used as the sole base fluid or in conjunction with other base fluids. Ideally, these other fluids would themselves have fair to good inherent biodegradability. Exemplary fluids that may be used with the fluids of the present invention include vegetable oils (e.g., rapeseed oil, canola oil, etc.), vegetable oil derivatives (e.g., estolide esters), or even synthetic dicarboxylic acid esters, which have high biodegradability and good viscosity characteristics. In applications where high overall biodegradability is not a requirement, the products of the present invention can be used together with conventional polyalphaolefins (i.e., hydrogenated 1-alkene hydrocarbon liquid oligomers), mineral oil, or gas liquefied fluids when used as minor components of the overall formulation.

[0046] Additives are often necessary to enhance specific performance attributes of formulated oils that may incorporate the fluids of the present invention. These additives may or may not themselves be biodegradable and include materials such as antiwear agents, detergents, viscosity index improvers, friction modifiers, fuel economy additives, antioxidants or heat stabilizers, dispersants, extreme pressure agents, tackifiers, rust inhibitors, wax modifiers, antifoaming agents, copper passivators, sulfur scavengers, seal swell agents, color stabilizers, and the like. The fluids of the present invention may be used in conjunction with additives that are themselves designed to be biodegradable. Where possible, additives should be selected so as not to substantially interfere with the biodegradability of the overall composition.

[0047] Example 11 Tractor fluid demonstration incorporating the 3.9 cSt fluid of the present invention [Table 12]

[0048] Example 12 Demonstration of an environmentally friendly chain oil incorporating the 3.9 cSt fluid of the present invention. [Table 13]

[0049] Example 13 Demonstration of two-stroke marine oil incorporating the fluid of the present invention. [Table 14]

[0050] Example 14 Demonstration of a biodegradable marine multigrade gear / stern tube oil. [Table 15]

[0051] Conventional lubricants The synthetic fluids of the present invention are expected to be used wherever hydrogenated 1-decene oligomers of similar viscosity are used. Applications include, but are not limited to, automotive crankcase oils, heavy-duty diesel oils, automatic transmission fluids, continuously variable transmission fluids, and industrial and automotive gear oils, compressor / turbine oils, especially those that benefit from the energy-saving features inherent in low viscosity fluids such as low and ultra-low viscosity 0W-XX engine oils where X is 16 or less. Several demonstration formulations have been devised to illustrate the suitability of the fluids of the present invention for several 0W-XX formulations.

[0052] Passenger car motor oil The synthetic fluids made according to this invention are ideally suited for use as components in fully synthetic and / or semi-synthetic lubricating oils for use in internal combustion engines. The fluids of this invention can be used as full-base lubricants or can be blended with other lubricating oils, including Group I, II, or III mineral oils, GTL (gas-to-liquid) oils, synthetic ester oils (e.g., di-2-ethylhexyl adipate, trimethylolpropane tripelargonate, etc.), alkyl naphthalene oils (e.g., di-dodecyl naphthalene, di-tetradecyl naphthalene, etc.), and the like. Lubricating oils used in internal combustion engines are typically formulated to contain conventional lubricating oil additives such as calcium aryl sulfonates, overbased calcium sulfonates, calcium or barium phenates, overbased magnesium alkylbenzene sulfonates, zinc dialkyldithiophosphates, VI improvers (e.g., ethylene-propylene copolymers, polyalkyl methacrylates, etc.), ashless dispersants (e.g., polyisobutylene succinimides of tetraethylenepentamine, polyisobutylenephenol-formaldehyde-tetraethylenepentamine Mannich condensation products, etc.), pour point depressants, friction modifiers, rust inhibitors, demulsifiers, oil-soluble antioxidants (e.g., hindered phenols or alkylated diphenylamines), various sulfurized components, and anti-foaming agents (antifoam agents).

[0053] As used herein, synthetic oils or base stocks are lubricants derived from artificially created compounds. Synthetic lubricants can be produced using chemically modified petroleum components, such as ethylene, the starting material from which alpha-olefins are derived, or can be synthesized from other non-petroleum sources. Synthetic base stocks are man-made and have a controlled molecular structure with predictable properties, unlike mineral base oils, which are usually complex mixtures of naturally occurring hydrocarbons. Mineral oils or petroleum-refined oils are defined as API Group I, II, II+, III, and III+ base oil stocks.

[0054] Although API Group III base oils are sometimes considered fully synthetic, for the purposes of this specification, Group III / Group III+ base oils are classified as mineral-based stocks. Lubricants that contain synthetic lubricants and do not contain API Group I, II, II+, III, and III+ mineral-based stocks are considered fully synthetic. Lubricants that contain synthetic lubricants used in combination with API Group I, II, II+, III, and III+ base stocks are considered "semi-synthetic" or "partial synthetic." In both partial and fully synthetic oils, the base stock is combined with an additive package, individual performance additives, and esters (usually API Group V) or other solubility enhancers.

[0055] Unique combinations of such additives, called additive packages, are tailored to specific base oils and applications and are commercially available from several sources, including Lubrizol, Infinium, and Afton Corp. Viscosity index (VI) improvers are available from these and other suppliers. The fluids of the present invention can be used to formulate passenger car motor oils in 0W-XX viscosity grades where their energy saving qualities are desirable. Example 15 Passenger car demonstration oil The following 0W-16 fully and partially synthetic passenger car motor oils were formulated containing the fluids of the present invention: [Table 16]

[0056] Example 16 When 4 cSt Group III mineral oil was replaced with a 4 cSt fluid of the present invention blended with a 6 cSt Group III oil and a pour point depressant, the resulting blend had a lower pour point, lower cold cranking viscosities at -30°C and -35°C, and a higher flash point.

[0057] [Table 17]

[0058] Example 17 Partial synthesis 0W-16 PCMO [Table 18] Preferred embodiments of the present invention are as follows. [1] A process for producing a polyalphaolefin fluid having predetermined properties, comprising: a. BF in combination with alcohol alkoxylate accelerator 3 In the presence of a catalyst system consisting of about 30 to about 100% 1-tetradecene (C 14 reacting an alpha olefin component comprising at least one alpha olefin containing 2-(2-methyl-2-propanol)-2-one to form a reacted bottoms product and unreacted residual monomers; b. removing the unreacted residual monomer as an overhead fraction by distillation; and c. hydrogenating at least a portion of said bottoms product to obtain a hydrogenated fluid having a viscosity at 100° C. of about 2.5 to about 4.6 centistokes. The process includes: [2] Alpha olefin component is more than 90% C 14 The process according to claim 1, wherein the process comprises an alpha olefin. [3] Polyalphaolefin fluid dimer C 28 The process according to claim 2, wherein the content is greater than 70%. [4] The alpha olefin component comprises a first alpha olefin and a second alpha olefin, and the first alpha olefin is C 14 an alpha olefin and a second olefin 12 The process according to [1] above, wherein the olefin is an alpha olefin. [5] Polyalphaolefin fluid C 14 / C 12 The process of claim 4, wherein the co-dimer content is greater than 80%. [6] The alpha olefin component comprises a first alpha olefin and a second alpha olefin, and the first alpha olefin is C 14 an alpha olefin and a second olefin 8 The process according to [1] above, wherein the dimer is an alpha olefin dimer. [7] Polyalphaolefin fluid C 14 / C 16 7. The process of claim 6, wherein the co-dimer content is greater than 80%. [8] A lubricant composition having a 100°C viscosity of about 4 cSt, a 250°C Noack volatility loss of less than 19% and a 200°C Noack volatility loss of less than 4%, a viscosity index of greater than 125, a pour point of less than -35°C, and a cold crank simulator viscosity at -35°C of less than 1,500 cP. [9] A lubricant composition having a viscosity at 100°C of about 3.4 cSt, a Noack volatility loss at 200°C of 4%, a pour point of about -50°C, and a Brookfield viscosity at -40°C of less than 1,750 cP.

[10] A lubricant composition having a viscosity at 100°C of about 4 cSt, a Noack volatility loss at 250°C of 13.9%, a pour point of about -59°C, and a cold crank simulator viscosity at -35°C of less than 1,700 cP.

[11] The process of [1], wherein the alcohol alkoxylate promoter in step (a) is 2-methoxyethanol.

[12] The process according to [1], wherein the alcohol alkoxylate promoter in step (a) is 1-methoxy-2-propanol.

[13] A formulated fully or partially synthetic lubricating oil comprising a hydrogenated fluid having a viscosity at 100°C of about 2.5 to about 4.6 centistokes.

[14] a. 1 to 97 percent of the hydrogenated fluid having a viscosity at 100°C of about 2.5 to about 4.6 centistokes; and b. 0 to 60 percent fluids selected from the group consisting of synthetic esters, synthetic hydrocarbon fluids, mineral oils, natural esters, or hydrocarbon oils derived from natural and petroleum-sourced materials, and combinations thereof; and c. 0.1 to 30 percent of an additive selected from the group consisting of dispersants, antioxidants, antiwear agents, antifoam agents, corrosion inhibitors, detergents, seal swell agents, viscosity improvers, and combinations thereof The lubricating oil formulated according to

[13] above, comprising a mixture of

[15] a. 1 to 97 percent of the hydrogenated fluid having a viscosity at 100°C of about 2.5 to about 4.6 centistokes; and b. 0 to 60 percent of a component selected from the group consisting of natural or synthetic esters, natural or synthetic hydrocarbon fluids, or hydrocarbon oils derived from natural and petroleum-sourced materials, and combinations thereof; and c. 0.1 to 70 percent of additives selected from the group consisting of dispersants, antioxidants, antiwear agents, antifoam agents, corrosion inhibitors, detergents, seal swell agents, viscosity improvers, and combinations thereof The lubricating oil formulated according to

[13] above, comprising a mixture of

[16] a. 1 to 98 percent of the hydrogenated fluid having a viscosity at 100°C of about 2.5 to about 4.6 centistokes; and b. 0 to 60 percent of a component selected from the group consisting of natural or synthetic esters, natural or synthetic hydrocarbon fluids, or hydrocarbon oils derived from natural and petroleum-sourced materials, and combinations thereof; and c. 0.1 to 70 percent of additives selected from the group consisting of dispersants, antioxidants, antiwear agents, antifoam agents, corrosion inhibitors, detergents, seal swell agents, viscosity improvers, and combinations thereof The lubricating oil formulated according to

[13] above, comprising a mixture of

Claims

1. 100°C viscosity of 4 cSt, 250°C Noack volatility loss of less than 19% and 200°C Noack volatility loss of less than 4%, viscosity index greater than 125, pour point less than -35°C, cold crank simulator viscosity at -35°C less than 1,500 cP, at least 50 percent biodegradability as determined by OECD 301B test, and greater than 70% by weight dimer C 28 A hydrogenated polyalphaolefin fluid having a content of

2. Viscosity at 100°C of 3.4 cSt, Noack volatility at 200°C of 4%, pour point at -50°C, Brookfield viscosity at -40°C of less than 1,750 cP, at least 50 percent biodegradability as determined by OECD 301B test, and greater than 70% by weight dimer C. 28 A hydrogenated polyalphaolefin fluid having a content of

3. 4 cSt viscosity at 100°C, 13.9% Noack volatility at 250°C, -59°C pour point, cold crank simulator viscosity at -35°C less than 1,700 cP, at least 50 percent biodegradability as determined by OECD 301B test, and greater than 70% by weight dimer C. 28 A hydrogenated polyalphaolefin fluid having a content of

4. Viscosity at 100°C of 2.5 to 4.6 centistokes, at least 50 percent biodegradability as determined by OECD 301B test, and greater than 70% by weight dimer C 28 A formulated fully or partially synthetic lubricating oil comprising a polyalphaolefin hydrogenated fluid having a content.

5. a. 1 to 97 percent of the hydrogenated fluid having a viscosity at 100° C. of 2.5 to 4.6 centistokes; and b. 0 to 60 percent of a fluid selected from the group consisting of synthetic esters, synthetic hydrocarbon fluids, mineral oils, natural esters, or hydrocarbon oils derived from natural and petroleum-sourced sources, and combinations thereof; and c. 0.1 to 30 percent additives selected from the group consisting of dispersants, antioxidants, antiwear agents, antifoam agents, corrosion inhibitors, detergents, seal swell agents, viscosity improvers, and combinations thereof 5. The formulated lubricating oil of claim 4, comprising a mixture of:

6. a. 1 to 97 percent of the hydrogenated fluid having a viscosity at 100° C. of 2.5 to 4.6 centistokes; and b. 0 to 60 percent of a component selected from the group consisting of natural or synthetic esters, natural or synthetic hydrocarbon fluids, or hydrocarbon oils derived from natural and petroleum-sourced materials, and combinations thereof; and c. 0.1 to 70 percent additives selected from the group consisting of dispersants, antioxidants, antiwear agents, antifoam agents, corrosion inhibitors, detergents, seal swell agents, viscosity improvers, and combinations thereof 5. The formulated lubricating oil of claim 4, comprising a mixture of:

7. a. 1 to 98 percent of the hydrogenated fluid having a viscosity at 100° C. of 2.5 to 4.6 centistokes; and b. 0 to 60 percent of a component selected from the group consisting of natural or synthetic esters, natural or synthetic hydrocarbon fluids, or hydrocarbon oils derived from natural and petroleum-sourced materials, and combinations thereof; and c. 0.1 to 70 percent additives selected from the group consisting of dispersants, antioxidants, antiwear agents, antifoam agents, corrosion inhibitors, detergents, seal swell agents, viscosity improvers, and combinations thereof 5. The formulated lubricating oil of claim 4, comprising a mixture of:

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