Lubricating oil of Graphene based on nitrogenous surface modifying agent and preparation method thereof
Technical field
The present invention relates to lubricating oil field, a kind of lubricating oil of Graphene based on nitrogenous surface modifying agent and preparation method thereof.
Background technology
The greasy property of electromotor and the safe and environment-friendly of automobile and the performance such as energy-conservation are closely bound up, along with improving constantly of engine performance, increasingly sophisticated, harsh to the requirement in terms of lubrication, in order to improve engine lubrication performance, realize anti-attrition energy-conservation, improve mechanical efficiency lube oil additive also arise at the historic moment.The most conventional additive is divided into the oil soluble additive of polar functionalities and has the big class of solid additive two of special layer structure.
Graphene, as a kind of carbonaceous new material with two-dimensional structure, has the character of a series of excellences such as higher specific surface area, heat conductivity and mechanical property.Graphene is added in lubricating oil as solid additive, obvious anti-attrition energy-saving effect can be played.But how to prevent Graphene additive in use produce layering and deposited phenomenon, be researcher have to faced by technical problem.
Summary of the invention
For the problems referred to above, the present invention proposes a kind of lubricating oil of Graphene based on nitrogenous surface modifying agent and preparation method thereof, to improve the dispersion stabilization of Graphene, improves the lubricity of electromotor.
As one aspect of the present invention, the invention provides the lube oil additive of a kind of Graphene based on nitrogenous surface modifying agent, comprising the Graphene of nitrogenous surface modifying agent, the Graphene of described nitrogenous surface modifying agent mass percent in lubricating oil is 0.002-1%.
Wherein, the Graphene of described nitrogenous surface modifying agent mass percent in lubricating oil is 0.1-0.5%.
Wherein, described nitrogenous surface modifier includes but not limited to selected from the chain alkyl amine that carbon number is 4-16, and has the compound of the groups such as amide groups, imide, glucose amido, pyrrole radicals or pyridine radicals.
Wherein, described nitrogenous surface modifier is ethylenediamine, hexamethylene diamine, acetamide, galactosamine.
Wherein, described nitrogenous surface modifier is preferably ethylenediamine or hexamethylene diamine.
Wherein, described lubricating oil is the automobile oil of commercialization.
Wherein, the Graphene of described nitrogenous surface modifying agent is by being added in the organic solvent containing described nitrogenous surface modifier by the aqueous solution of described Graphene, being formed biphase, is stirred vigorously the product that reaction obtains.
Wherein, the thickness of described Graphene is 0.17-1.4nm, and sheet footpath size is 1~50 μm.
As another aspect of the present invention, the invention provides the lubricating oil of a kind of Graphene based on nitrogenous surface modifying agent, include the lube oil additive of as above Graphene based on nitrogenous surface modifying agent described in any one.
As another aspect of the invention, the invention provides the preparation method of the lube oil additive of a kind of Graphene based on nitrogenous surface modifying agent, comprise the following steps:
Prepare the aqueous solution of graphene oxide;
The described graphene oxide water solution of preparation is mixed with the organic solvent containing nitrogenous surface modifier, is formed biphase, be warmed up to 60-90 DEG C, after being stirred vigorously lower reaction 3-12 hour, obtain target product.
Wherein said nitrogenous surface modifier is ethylenediamine, hexamethylene diamine, acetamide or galactosamine.
Wherein, described organic solvent is preferably toluene or hexamethylene.
Wherein, described Graphene thickness is 0.17-1.4nm, and sheet footpath size is 1~50 μm.
As another aspect of the invention, present invention also offers the preparation method of a kind of lubricating oil based on nitrogenous surface modifying agent Graphene, comprise the following steps:
The lube oil additive of the Graphene based on nitrogenous surface modifying agent as above any one prepared is directly appended in lubricating oil, stirring mixing, obtains target product;
Wherein, the lube oil additive of described prepared Graphene based on nitrogenous surface modifying agent mass percent in described lubricating oil is 0.002-1%.
Wherein, the described prepared lube oil additive based on nitrogenous surface modifying agent Graphene mass percent in described lubricating oil is 0.1-0.5%.
As another aspect of the invention, present invention also offers the application in lubricating oil of the lube oil additive of Graphene based on nitrogenous surface modifying agent described in a kind of as above any one.
The present invention uses two phase process to realize graphenic surface and processes, and prepares oil-soluble Graphene.The method is simple, and repetitive rate is high, is suitable for large-scale industrialization and produces.The lube oil additive of the present invention, there is good dispersibility, avoid the use of tradition dispersant, effectively increase the anti-wear performance of lubricating oil and reduce the loss of electromotor, be possible to prevent layering and deposited phenomenon that Graphene additive in use produces.
Detailed description of the invention
For making the object, technical solutions and advantages of the present invention clearer, below in conjunction with specific embodiment, the present invention is described in further detail.
Lubricating oil; it is used in all kinds automobile, plant equipment reducing friction; protect machinery and the liquid of workpiece or semisolid lubricants; act primarily as lubrication, cooling, antirust, clean, seal and the effect such as buffering; by its source point animal oil, vegetable oil, petroleum oil and the big class of synthetic lubricant fluid four.The all types of automobile oils that lubricating oil is commercialization used in the present invention.
Nitrogenous surface modifier refers to chain alkyl amine that carbon number is 4-16 and has the compound of the groups such as amide groups, imide, glucose amido, pyrrole radicals or pyridine radicals, such as ethylenediamine, hexamethylene diamine, acetamide, galactosamine etc., the most preferably ethylenediamine, hexamethylene diamine.
Graphene used in the present invention, can be various known Graphenes, such as it is by mechanically pulling off Graphene prepared by the methods such as method, chemical oxidization method, crystal epitaxy method, chemical vapour deposition technique, organic synthesis method and CNT stripping method, can also be through being processed further the Graphene processed, such as single-layer graphene, graphene oxide, reduced graphene, functionalization graphene etc..The thickness of described Graphene and sheet footpath are neglected greatly and are actually needed selection, and preferred thickness is 0.17-1.4nm, and sheet footpath size is 1~50 μm.
The invention discloses the lube oil additive of a kind of Graphene based on nitrogenous surface modifying agent, in lubricating oil, wherein with the addition of the Graphene that nitrogenous surface modifier is surface-treated, the mass percent shared in described lubricating oil of the surface-treated Graphene of described nitrogenous surface modifier is 0.002-1%, preferably 0.1-0.5%.
Described lubricating oil can be all types automobile oil of commercialization, can also add various known lube oil additive, such as antioxidant, dispersant, antiwear additive, viscosity index improver etc. in described lubricating oil.
The invention also discloses the preparation method of the lube oil additive of a kind of Graphene based on nitrogenous surface modifying agent, comprise the following steps:
Graphene is dissolved in ultra-pure water, ultrasonic machine ultrasonic disperse, prepares Graphene weak solution;
Choosing nitrogenous surface modifier to be dissolved in organic solution, described organic solvent can be toluene or hexamethylene;
By the Graphene weak solution of preparation and the organic solution mixing containing nitrogenous surface modifier, formed biphase, be warmed up to 60-90 DEG C, be stirred vigorously lower reaction 3-12 hour;
Washing by the mixed solutions for many times of first alcohol and water, wherein methanol and water volume ratio for example, 3: 7, are centrifugally separating to obtain target product.
And to prepare the lubricating oil of Graphene based on nitrogenous surface modifying agent, it is only necessary to the lube oil additive of above-mentioned prepared Graphene based on nitrogenous surface modifying agent is directly appended in lubricating oil, stirring mixing, obtains target product.
In above-mentioned preparation method, Graphene thickness is 0.17-1.4nm, and sheet footpath size is 1~50 μm.The lube oil additive of above-mentioned prepared Graphene based on nitrogenous surface modifying agent, i.e. modified graphene mass percent in lubricating oil is 0.002-1%, preferably 0.1-0.5%.
Below in conjunction with specific embodiment, the present invention is illustrated in more detail.
Embodiment 1
The preparation of graphite oxide: use Hummer method, adds 2g crystalline flake graphite powder in the beaker of a 250mL, is added thereto to 1g NaNO under conditions of ice-water bath3The H of rear addition 46mL 98%2SO4And it is sufficiently stirred for;It is slowly added to 6g KMnO4, keep the temperature of solution and to keep this condition 5 minutes more than 20 DEG C, then remove ice-water bath and be heated to 35 DEG C, keep this condition 30 minutes;Adding the water of 92mL, be stirred for 15 minutes, temperature will be increased to about 98 DEG C;Continuously add the hydrogen peroxide of 60 DEG C 3% of 80mL, with centrifuge liquid after centrifugal above-mentioned process in 30 minutes under 7200 turns;Residue is cleaned until the pH of upper strata suspension is about 7 with hot water;The powder obtained is dispersed back in water ultrasonic 15 minutes, after having filtered black residue, obtains a kind of homogeneous suspension;Obtaining graphite oxide (alkene) after suspension lyophilizing.
Graphite oxide (alkene) powder obtained by 1g is dissolved in deionized water, ultrasonic disperse 1 hour, add the ethylenediamine toluene solution that 5.3g concentration is 0.25mol/L, it is warming up to 80 DEG C, it is heated to reflux, prepare, by two phase process, the Graphene that ethylenediamine surface processes, clean, filter and be dried to obtain the graphene powder of ethylenediamine surface modification.The Graphene of the ethylenediamine surface modification that mass percent is 0.15% is joined in lubricating oil, stirs one hour, obtain the lubricating oil of Graphene based on ethylenediamine surface modification.
Above-mentioned being dissolved in the step of water by graphite oxide, the addition of graphite oxide powder can adjust with visual response degree, such as, can add 250-500g deionized water with 1~1.5g graphite oxide powder.
Embodiment 2
Reaction raw materials and condition with embodiment 1, differ only in addition be 5.3g concentration be the ethylenediamine toluene solution of 0.5mol/L.
Embodiment 3
Reaction raw materials and condition, with embodiment 1, differ only in graphite oxide (alkene) powder being to be obtained by 1.5g and are dissolved in 100ml deionized water, add the galactosamine toluene solution that 5.3g concentration is 0.25mol/L.
Embodiment 4
Reaction raw materials and condition, with embodiment 1, differ only in and join in lubricating oil by the Graphene of the ethylenediamine surface modification that mass percent is 0.002%, stir one hour.
Embodiment 5
Reaction raw materials and condition, with embodiment 1, differ only in and join in lubricating oil by the Graphene of the ethylenediamine surface modification that mass percent is 1%, stir one hour.
Embodiment 6
Reaction raw materials and condition, with embodiment 3, differ only in and join in lubricating oil by the Graphene of the galactosamine surface modification that mass percent is 0.30%, stir one hour.
Comparative example 1-2
Prepare the method for graphene powder with embodiment 1, differ only in and be added without nitrogenous surface modifier and carry out two phase process reaction described graphene powder is carried out surface process.
Respectively the graphene powder of the non-surface modification that mass percent is 0.001% and 1% is joined in lubricating oil, stir one hour.
Storage stability is tested
Prepared target product is stood 15 days, 30 days, the situation of object observing product.
Through experiment, after 15 days, with the addition of in the lubricating oil of the Graphene lube oil additive not carrying out surface process and occur in that layering of significantly reuniting, and with the addition of the lubricating oil of surface treated Graphene lube oil additive, after 30 days, still can not observe substantially reunite or layering with stable dispersion.
Table 1 embodiment 1-6 and comparative example's 1-2 stable storing performance table
The energy-conservation performance test of anti-attrition
The anti-attrition energy-efficient performance of test target product is carried out by four-ball tester and gear testing machine.
Finding through experiment, when the mass percent of surface-treated Graphene is 0.1-0.5%, the anti-attrition energy-saving effect of lubricating oil is best.
Particular embodiments described above; the purpose of the present invention, technical scheme and beneficial effect are further described; it it should be understood that; the foregoing is only the specific embodiment of the present invention; it is not limited to the present invention; all within the spirit and principles in the present invention, any modification, equivalent substitution and improvement etc. done, should be included within the scope of the present invention.