An environmentally friendly composite lubricant and its preparation method

Abstract

This application relates to the field of lubricating compositions, and specifically discloses an environmentally friendly composite lubricant and a preparation method thereof. An environmentally friendly composite lubricant includes: 30-40 parts of oleic acid amide, 10-20 parts of lauramide, 5-10 parts of tung oil, 10-18 parts of emulsifier, 1-3 parts of defoamer, 1-3 parts of high-temperature resistant filler, 0.5-1 part of antioxidant, and 30-50 parts of water. The preparation method is as follows: S1. Weigh oleic acid amide, tung oil, emulsifier, and water, mix them, heat up to 70-80 °C, then add the high-temperature resistant filler, and mix and stir evenly to obtain a preliminary mixture; S2. Add lauramide to the preliminary mixture, heat up to 105-110 °C, continue to stir evenly, and finally cool down, add the defoamer and antioxidant, and mix and stir evenly to obtain the finished lubricant; it has both internal lubrication and external lubrication effects, and has the advantages of high temperature resistance and environmental protection.

Description

Technical Field

[0001] This application relates to the field of lubricating compositions, and more specifically, it relates to an environmentally friendly composite lubricant and a preparation method thereof. Background Art

[0002] A lubricant is a type of plastic additive, including internal lubricants and external lubricants. The external lubricant mainly improves the friction condition between the plastic melt and the metal surface of the molding processing equipment, reduces the friction force between the two, and makes the plastic parts easy to demold; the internal lubricant plays a role in reducing the intermolecular cohesive force inside the plastic melt, can reduce the internal friction of the plastic melt, increase the melting rate and melt deformability of the plastic, reduce the melt viscosity and improve the plasticizing performance.

[0003] However, in some special plastic processing processes, it is often necessary to be molded under high-temperature environments. Under high-temperature conditions, the external lubricant is prone to volatilization and loss, reducing the lubrication effect. Moreover, high temperature is also likely to cause the oil film formed by the external lubricant to rupture and lose the lubrication effect; the internal lubricant is prone to oxidation and degradation under high-temperature conditions, generating harmful substances. If the harmful substances leak, it is easy to have an impact on the soil, water bodies, and the ecosystem.

[0004] Therefore, how to prepare a new composite lubricant that has both internal lubrication and external lubrication effects and has the advantages of high temperature resistance and environmental protection is a problem to be solved. Summary of the Invention

[0005] In order to prepare a new composite lubricant that has both internal lubrication and external lubrication effects and has the advantages of high temperature resistance and environmental protection, this application provides an environmentally friendly composite lubricant and a preparation method thereof.

[0006] In the first aspect, this application provides an environmentally friendly composite lubricant, adopting the following technical solution:

[0007] An environmentally friendly composite lubricant contains the following raw materials in parts by weight: 30 - 40 parts of oleic acid amide, 10 - 20 parts of lauric acid amide, 5 - 10 parts of tung oil, 10 - 18 parts of emulsifier, 1 - 3 parts of defoamer, 1 - 3 parts of high-temperature resistant filler, 0.5 - 1 part of antioxidant, and 30 - 50 parts of water.

[0008] By adopting the above technical solution, oleic acid amide, lauric acid amide, and tung oil are combined. Utilizing the interaction between the amide groups in oleic acid amide and lauric acid amide, they are evenly distributed in plastic molecules. Oleic acid amide and lauric acid amide penetrate between the layers of ions and within the particles of the plastic resin, reducing the friction between plastics and the friction between plastics and processing equipment, enabling the prepared lubricant to have both internal lubrication effect and external lubrication effect; moreover, oleic acid amide, lauric acid amide, and tung oil can form a lubricating film on the plastic surface, further improving the external lubrication effect; at the same time, the polar groups in oleic acid amide and lauric acid amide can weaken the intermolecular force of the melt, promote the flow of the melt, reduce the melt viscosity, and further improve the internal lubrication effect.

[0009] Lauric acid amide, tung oil, high-temperature resistant filler, and antioxidant are combined. Utilizing the heat resistance of lauric acid amide and tung oil, the high-temperature resistant effect of the filler, and the high-temperature antioxidant effect, it is not easy for the oil film of the lubricant to rupture, and it is not easy to volatilize and dissipate; combined with the environmental protection effect of oleic acid amide and tung oil, thus enabling the composite lubricant to have the advantages of internal lubrication, external lubrication, high temperature resistance, and environmental protection at the same time.

[0010] Preferably, the oleic acid amide is prepared by the following method:

[0011] Oleic acid amide particles are added to hot ethanol and stirred until all the oleic acid amide is dissolved to obtain a solution with a mass fraction of 2 - 7%. Then, ultrasonic oscillation treatment is carried out for 5 - 10 min, and then a dopamine hydrochloride solution is added. The mass ratio of the solution to the dopamine hydrochloride solution is 1:0.1 - 0.25. After the reaction, through separation and purification, oleic acid amide is obtained.

[0012] By adopting the above technical solution, oleic acid amide particles are dissolved in hot ethanol, and then through ultrasonic oscillation, the oleic acid amide is evenly dispersed, and it helps to break chemical bonds. Combined with the amino group of dopamine hydrochloride, it is convenient for amino groups to adhere to the surface of oleic acid amide molecules, thereby realizing amino loading. The amino loading of dopamine hydrochloride can further improve the high-temperature resistance of oleic acid amide, so that during the processing of plastics at a relatively high temperature, problems such as volatilization and loss of the lubricant are not likely to occur, ensuring that the lubricant still has good internal lubrication and external lubrication effects under high-temperature processing conditions.

[0013] Preferably, the frequency of the ultrasonic oscillation treatment is 20 - 40 kHz, and the time is 5 - 10 min.

[0014] By adopting the above technical solution, the frequency and time of ultrasonic oscillation are limited to ensure amino loading and not easily over-destroy the structure of oleic acid amide, thereby improving the high-temperature resistant lubrication effect of oleic acid amide.

[0015] Preferably, the dopamine hydrochloride solution is a dopamine hydrochloride hot ethanol solution with a mass fraction of 1 - 5%.

[0016] By adopting the above technical solution, dopamine hydrochloride is dissolved in hot ethanol. During the ultrasonic oscillation process, dopamine hydrochloride is evenly dispersed and comes into contact with the molecules of oleic acid amide. Taking advantage of the amino group of dopamine hydrochloride being convenient for contacting with the amide group of oleic acid amide, the amino group of dopamine hydrochloride is loaded onto oleic acid amide, improving the high-temperature lubrication effect of oleic acid amide.

[0017] Preferably, the lauric acid amide is prepared from a lauric acid amide solution and graphite nanosheets with a mass ratio of 1:0.05 - 0.15.

[0018] By adopting the above technical solution, graphite nanosheets are evenly dispersed in the lauric acid amide solution. Utilizing the layered structure of graphite nanosheets, the lauric acid amide attached to the surface of graphite nanosheets has a larger specific surface area, facilitating uniform contact with plastic molecules. When plastic molecules contact lauric acid amide, by using the barrier effect of the layered structure in combination with the lubrication effect of graphite nanosheets itself, the intermolecular force of plastic molecules can be further weakened, the viscosity of plastic molecules can be reduced, the viscosity of the plastic melt can be ensured, and the internal lubrication effect can be improved.

[0019] The combination of lauric acid amide and graphite nanosheets, taking advantage of the good heat resistance effect of graphite nanosheets and the dispersion effect of lauric acid amide in the layered structure of graphite nanosheets, further improves the high-temperature resistance effect of lauric acid amide. During the lubrication process, lauric acid amide can still have a good lubricating effect at a relatively high heating temperature; the combination of lauric acid amide and graphite nanosheets. When an oil film is formed on the plastic surface by lauric acid amide and oleic acid amide, by using the layered structure of graphite nanosheets and combining with the relatively high mechanical strength and stability of graphite nanosheets, the stability of the oil film is further improved, and the problem of oil film rupture is not likely to occur under high-temperature processing conditions, ensuring that the composite lubricant has a good high-temperature lubrication effect.

[0020] Preferably, the graphite nanosheets are prepared by loading a polyethylene glycol solution on graphite nanosheet microparticles.

[0021] By adopting the above technical solution, when graphite nanosheets are dispersed in the lauric acid amide solution, the hydroxyl groups of the polyethylene glycol solution are loaded on the surface of graphite nanosheet microparticles. Taking advantage of the hydroxyl groups of polyethylene glycol being convenient for connecting with the amino group of dopamine hydrochloride on oleic acid amide, the connection between oleic acid amide and lauric acid amide is realized. The oleic acid amide and lauric acid amide evenly dispersed in plastic molecules form a lubrication network, reducing the intermolecular force of plastic molecules, improving fluidity, reducing the melt viscosity, and improving the high-temperature lubrication effect of the lubricant.

[0022] The hydroxyl groups of polyethylene glycol attached to the surface of graphite nanosheets are convenient for adsorbing and bonding with the amide group of lauric acid amide, further improving the connection effect between graphite nanosheets and lauric acid amide, thereby improving the high-temperature lubrication effect of lauric acid amide and ensuring that lauric acid amide has good internal and external lubrication effects during the high-temperature processing of plastic products.

[0023] Preferably, the high-temperature resistant filler is prepared from hydroxyapatite whiskers, nano boron nitride, and polyglutamic acid solution with a mass ratio of 1:1 - 2:0.5 - 1.

[0024] By adopting the above technical solution, the polyglutamic acid solution adheres to the surfaces of hydroxyapatite whiskers and nano boron nitride. Utilizing the amino and carboxyl groups in the polyglutamic acid on the surfaces of hydroxyapatite whiskers and nano boron nitride, it improves the adsorption connection effect between the high-temperature resistant filler and the amide groups in oleic acid amide and lauric acid amide, enhances the lubrication effect of the internal lubrication network within the plastic molecules, and improves the internal lubrication effect of the composite lubricant. Combining with the traction effect of hydroxyapatite whiskers and the load-bearing effect of nano boron nitride, it further improves the stability of the oil film formed by the composite lubricant on the plastic surface, and is not prone to problems such as high-temperature oil film rupture and damage. At the same time, hydroxyapatite whiskers and nano boron nitride have good high-temperature resistance, which can further improve the oil film stability, thereby improving the external lubrication effect of the composite lubricant.

[0025] Preferably, the defoaming agent is polydimethylsiloxane.

[0026] By adopting the above technical solution, polydimethylsiloxane has a low surface tension, can uniformly penetrate between plastic molecules, reduce the surface tension of the foam liquid film, thereby accelerating the foam rupture. And polydimethylsiloxane has stable chemical properties and also has a good environmental protection effect, making the composite lubricant have good lubrication and environmental protection effects.

[0027] Preferably, the antioxidant is antioxidant 1010.

[0028] By adopting the above technical solution, antioxidant 1010 has good thermal stability. Even when processing plastics under high-temperature conditions, it is not prone to problems such as high temperature causing the loss of lubricant. And it has a good antioxidant effect, can effectively prevent the polymer material from being oxidized by heat, making the finished composite lubricant have good stability under higher processing temperature conditions, and thus have good high-temperature resistant lubrication effect.

[0029] In the second aspect, the present application provides a preparation method of an environmentally friendly composite lubricant, adopting the following technical solution:

[0030] A preparation method of an environmentally friendly composite lubricant includes the following steps:

[0031] S1. Weigh oleic acid amide, tung oil, emulsifier, and water, heat up to 70 - 80 °C, and then add the high-temperature resistant filler, mix and stir evenly to obtain a preliminary mixture.

[0032] S2. Add lauric amide to the premix, heat it up to 105 - 110 °C, continue to stir evenly, and finally cool down. Then add defoamer and antioxidant, and mix and stir evenly to obtain the finished lubricant.

[0033] By adopting the above technical solution, oleic acid amide and tung oil are combined. Under the condition of 70 - 80 °C, it is ensured that oleic acid amide and tung oil are in a liquid state, and then the high-temperature resistant filler is evenly dispersed. The temperature in the premix is raised to 105 - 110 °C to ensure the melting of lauric amide crystals. After mixing evenly, lauric amide, oleic acid amide, and tung oil are evenly dispersed and bonded to the high-temperature resistant filler to form a lubrication network, which is evenly dispersed within the plastic molecules, thereby reducing the viscosity of the plastic melt and improving the internal lubrication effect. Moreover, the lubrication network can form a uniformly distributed oil film on the surface of the plastic molecules. The oil film is connected by the high-temperature resistant filler, further improving the high-temperature lubrication effect of the composite lubricant; combined with the antioxidant, under high-temperature conditions, the composite lubricant is not prone to problems such as oxidation and volatilization, ensuring the high-temperature stability of the composite lubricant.

[0034] In summary, the present application has the following beneficial effects:

[0035] 1. Oleic acid amide, lauric amide, and tung oil are combined. By utilizing the interaction between the amide groups in oleic acid amide and lauric amide, they are evenly distributed in the plastic molecules. Oleic acid amide and lauric amide penetrate between the layers of ions and within the particles of the plastic resin, reducing the friction between plastics and the friction between plastics and processing equipment, so that the prepared lubricant has both internal lubrication effect and external lubrication effect.

[0036] 2. Lauric amide, tung oil, high-temperature resistant filler, and antioxidant are combined. By utilizing the heat resistance of lauric amide and tung oil, combined with the high-temperature resistance effect of the filler and the high-temperature antioxidant effect, it is not easy to break the oil film of the lubricant, and it is not easy to volatilize and dissipate; combined with the environmental protection effect of oleic acid amide and tung oil, the composite lubricant has the advantages of internal lubrication, external lubrication, high-temperature resistance, and environmental protection. Specific Embodiments

[0037] The following further elaborates on the present application with reference to embodiments.

[0038] Preparation Example of Oleic Acid Amide

[0039] Among the following raw materials, dopamine hydrochloride was purchased from Hubei Yongkuo Technology Co., Ltd.; other raw materials are all commercially available.

[0040] Preparation Example 1: Oleic acid amide was prepared by the following method:

[0041] The oleic acid amide particles are added at a temperature of 70°C and stirred with hot ethanol until all the oleic acid amide is dissolved. During this process, hot ethanol is continuously added. The mass fraction of ethanol is 99%, and a solution with a mass fraction of 5% is obtained. Then, ultrasonic oscillation treatment is carried out for 8 minutes under the condition of a frequency of 30 kHz. Then, 2 kg of dopamine hydrochloride solution is added to 10 kg of the solution. The dopamine hydrochloride solution is a hot ethanol solution of dopamine hydrochloride with a mass fraction of 3%. The temperature of the hot ethanol in the dopamine hydrochloride hot ethanol solution is 70°C, and the mass fraction of ethanol is 95%. The reaction is maintained at 70°C and stirred for 20 minutes, and then cooled to room temperature to obtain a semi-finished product. The semi-finished product is distilled and purified to obtain oleic acid amide.

[0042] Preparation Example 2: The difference between this preparation example and Preparation Example 1 is that:

[0043] The oleic acid amide particles are added at a temperature of 70°C and stirred with hot ethanol until all the oleic acid amide is dissolved. During this process, hot ethanol is continuously added. The mass fraction of ethanol is 99%, and a solution with a mass fraction of 2% is obtained. Then, ultrasonic oscillation treatment is carried out for 10 minutes under the condition of a frequency of 20 kHz. Then, 1 kg of dopamine hydrochloride solution is added to 10 kg of the solution. The dopamine hydrochloride solution is a hot ethanol solution of dopamine hydrochloride with a mass fraction of 1%. The temperature of the hot ethanol in the dopamine hydrochloride hot ethanol solution is 70°C, and the mass fraction of ethanol is 95%. The reaction is maintained at 70°C and stirred for 20 minutes, and then cooled to room temperature to obtain a semi-finished product. The semi-finished product is distilled and purified to obtain oleic acid amide.

[0044] Preparation Example 3: The difference between this preparation example and Preparation Example 1 is that:

[0045] The oleic acid amide particles are added at a temperature of 70°C and stirred with hot ethanol until all the oleic acid amide is dissolved. During this process, hot ethanol is continuously added. The mass fraction of ethanol is 99%, and a solution with a mass fraction of 7% is obtained. Then, ultrasonic oscillation treatment is carried out for 5 minutes under the condition of a frequency of 40 kHz. Then, 2.5 kg of dopamine hydrochloride solution is added to 10 kg of the solution. The dopamine hydrochloride solution is a hot ethanol solution of dopamine hydrochloride with a mass fraction of 5%. The temperature of the hot ethanol in the dopamine hydrochloride hot ethanol solution is 70°C, and the mass fraction of ethanol is 95%. The reaction is maintained at 70°C and stirred for 20 minutes, and then cooled to room temperature to obtain a semi-finished product. The semi-finished product is distilled and purified to obtain oleic acid amide.

[0046] Preparation Examples of Lauric Acid Amide

[0047] The following raw materials are all commercially available.

[0048] Preparation Example 4: Lauric acid amide is prepared by the following method:

[0049] The lauric acid amide particles are heated to 110°C until completely melted to obtain a lauric acid amide melt.

[0050] Place 1 kg of graphite nanoplate particles into 5 kg of polyethylene glycol solution, and then ultrasonically disperse for 5 min under the condition of 20 kHz. The polyethylene glycol solution is an aqueous solution of polyethylene glycol with a mass fraction of 2%, and the polyethylene glycol is polyethylene glycol 800. Then filter out the excess polyethylene glycol solution, and after drying and dispersing until the graphite nanoplate particles do not adhere and agglomerate to each other, graphite nanoplates are obtained.

[0051] Add 0.1 kg of graphite nanoplates to 1 kg of lauroylamide melt. The addition rate of the graphite nanoplates is 30 g / min. During the addition process, the lauroylamide melt is stirred at a rotation speed of 100 r / min. After the addition is completed, continue to stir for 20 min. After mixing evenly, through cooling and dispersion, lauroylamide is obtained.

[0052] Preparation Example 5: The difference between this preparation example and Preparation Example 4 is as follows:

[0053] Add 0.05 kg of graphite nanoplates to 1 kg of lauroylamide melt. The addition rate of the graphite nanoplates is 30 g / min. During the addition process, the lauroylamide melt is stirred at a rotation speed of 100 r / min. After the addition is completed, continue to stir for 20 min. After mixing evenly, through cooling and dispersion, lauroylamide is obtained.

[0054] Preparation Example 6: The difference between this preparation example and Preparation Example 4 is as follows:

[0055] Add 0.15 kg of graphite nanoplates to 1 kg of lauroylamide melt. The addition rate of the graphite nanoplates is 30 g / min. During the addition process, the lauroylamide melt is stirred at a rotation speed of 100 r / min. After the addition is completed, continue to stir for 20 min. After mixing evenly, through cooling and dispersion, lauroylamide is obtained.

[0056] Preparation Examples of High-Temperature Resistant Fillers

[0057] All the following raw materials are commercially available.

[0058] Preparation Example 7: The high-temperature resistant filler is prepared by the following method:

[0059] Mix 1 kg of hydroxyapatite whiskers and 1.5 kg of nano boron nitride evenly to obtain a mixture. The average length of the hydroxyapatite whiskers is 100 nm, and the average particle size of the nano boron nitride is 10 nm. Then add 0.8 kg of polyglutamic acid solution. The polyglutamic acid solution is an aqueous solution of polyglutamic acid with a mass fraction of 2%. The addition rate of the polyglutamic acid solution is 60 mL / min. During the addition process, the mixture is continuously stirred at a rotation speed of 100 r / min. After mixing evenly, conduct dispersion so that the hydroxyapatite whiskers and nano boron nitride do not adhere and agglomerate to each other, and the finished high-temperature resistant filler is obtained.

[0060] Preparation Example 8: The difference between this preparation example and Preparation Example 7 is as follows:

[0061] 1 kg of hydroxyapatite whiskers and 1 kg of nano boron nitride were mixed evenly to obtain a mixed material. The average length of the hydroxyapatite whiskers was 100 nm, and the average particle size of the nano boron nitride was 10 nm. Then, 0.5 kg of polyglutamic acid solution was added. The polyglutamic acid solution was an aqueous solution of polyglutamic acid with a mass fraction of 2%. The addition rate of the polyglutamic acid solution was 60 mL / min. During the addition process, the mixed material was continuously stirred at a rotation speed of 100 r / min. After mixing evenly, it was dispersed, and there was no adhesion or agglomeration between the hydroxyapatite whiskers and the nano boron nitride, obtaining a finished high-temperature resistant filler.

[0062] Preparation Example 9: The difference between this preparation example and Preparation Example 7 is as follows:

[0063] 1 kg of hydroxyapatite whiskers and 2 kg of nano boron nitride were mixed evenly to obtain a mixed material. The average length of the hydroxyapatite whiskers was 100 nm, and the average particle size of the nano boron nitride was 10 nm. Then, 1 kg of polyglutamic acid solution was added. The polyglutamic acid solution was an aqueous solution of polyglutamic acid with a mass fraction of 2%. The addition rate of the polyglutamic acid solution was 60 mL / min. During the addition process, the mixed material was continuously stirred at a rotation speed of 100 r / min. After mixing evenly, it was dispersed, and there was no adhesion or agglomeration between the hydroxyapatite whiskers and the nano boron nitride, obtaining a finished high-temperature resistant filler.

[0064] Example

[0065] Example 1: An environmentally friendly composite lubricant:

[0066] 35 kg of oleic acid amide, 15 kg of lauric acid amide, 8 kg of tung oil, 14 kg of emulsifier, 2 kg of defoamer, 2 kg of high-temperature resistant filler, 1 kg of antioxidant, and 40 kg of water; the oleic acid amide was the oleic acid amide prepared in Preparation Example 1, the lauric acid amide was the lauric acid amide prepared in Preparation Example 4, the high-temperature resistant filler was the high-temperature resistant filler prepared in Preparation Example 7, the emulsifier was Tween 80, the defoamer was polydimethylsiloxane, and the antioxidant was antioxidant 1010;

[0067] The preparation method is as follows:

[0068] S1. Weigh oleic acid amide and tung oil, heat up to 75 °C, then add the high-temperature resistant filler, and mix and stir evenly to obtain a preliminary mixture;

[0069] S2. Add lauric acid amide to the preliminary mixture, heat up to 110 °C, continue to stir evenly, and finally cool down, add the defoamer and antioxidant, and mix and stir evenly to obtain the finished lubricant.

[0070] Example 2: The difference between this example and Example 1 is as follows:

[0071] 30 kg of oleic acid amide, 10 kg of lauric acid amide, 5 kg of tung oil, 10 kg of emulsifier, 1 kg of defoamer, 1 kg of high-temperature resistant filler, 0.5 kg of antioxidant, and 30 kg of water; the oleic acid amide is the oleic acid amide prepared in Preparation Example 2, the lauric acid amide is the lauric acid amide prepared in Preparation Example 5, the high-temperature resistant filler is the high-temperature resistant filler prepared in Preparation Example 8, the emulsifier is Tween 80, the defoamer is polydimethylsiloxane, and the antioxidant is antioxidant 1010;

[0072] The preparation method is as follows:

[0073] S1. Weigh oleic acid amide, tung oil, emulsifier, and water, mix them, heat up to 70 °C, then add the high-temperature resistant filler, and mix and stir evenly to obtain a preliminary mixture;

[0074] S2. Add lauric acid amide to the preliminary mixture, heat up to 105 °C, continue to stir evenly, finally cool down, add the defoamer and antioxidant, and mix and stir evenly to obtain the finished lubricant.

[0075] Example 3: The difference between this example and Example 1 is that:

[0076] 40 kg of oleic acid amide, 20 kg of lauric acid amide, 10 kg of tung oil, 18 kg of emulsifier, 3 kg of defoamer, 3 kg of high-temperature resistant filler, 1 kg of antioxidant, and 50 kg of water; the oleic acid amide is the oleic acid amide prepared in Preparation Example 3, the lauric acid amide is the lauric acid amide prepared in Preparation Example 6, the high-temperature resistant filler is the high-temperature resistant filler prepared in Preparation Example 9, the emulsifier is Tween 80, the defoamer is polydimethylsiloxane, and the antioxidant is antioxidant 1010;

[0077] The preparation method is as follows:

[0078] S1. Weigh oleic acid amide, tung oil, emulsifier, and water, mix them, heat up to 80 °C, then add the high-temperature resistant filler, and mix and stir evenly to obtain a preliminary mixture;

[0079] S2. Add lauric acid amide to the preliminary mixture, heat up to 110 °C, continue to stir evenly, finally cool down, add the defoamer and antioxidant, and mix and stir evenly to obtain the finished lubricant.

[0080] Example 4: The difference between this example and Example 1 is that:

[0081] In the raw materials, the oleic acid amide prepared in Preparation Example 1 is replaced with commercially available oleic acid amide of the same mass.

[0082] Example 5: The difference between this example and Example 1 is that:

[0083] In the raw materials, the lauric acid amide prepared in Preparation Example 4 is replaced with commercially available lauric acid amide of the same mass.

[0084] Example 6: The difference between this example and Example 1 is that:

[0085] During the preparation of lauramide in the raw materials, graphite nanoplate microparticles of the same mass were used to replace graphite nanoplates, that is, the graphite nanoplates were not treated with polyethylene glycol solution.

[0086] Example 7: The difference between this example and Example 1 is that:

[0087] Polyglutamic acid solution was not added during the preparation of the high-temperature resistant filler.

[0088] Example 8: The difference between this example and Example 1 is that:

[0089] Hydroxyapatite whiskers were not added during the preparation of the high-temperature resistant filler.

[0090] Comparative Example

[0091] Comparative Example 1: The difference between this comparative example and Example 1 is that:

[0092] Lauramide and tung oil were not added to the raw materials.

[0093] Comparative Example 2: The difference between this comparative example and Example 1 is that:

[0094] High-temperature resistant filler and tung oil were not added to the raw materials.

[0095] Performance Detection Test

[0096] 1. Detection of internal lubrication effect

[0097] Composite lubricants were prepared by the methods of Examples 1-8 and Comparative Examples 1-2 respectively. During the PVC melt extrusion process, the composite lubricant was added to PVC at a ratio of 0.5%, and melt extrusion was carried out by a single-screw extruder. Temperature: Zone 1 100°C; Zone 2 150°C; Zone 3 190°C; Die head 170°C; Rotation speed 40 r / min; Record the extrusion amount. A high extrusion amount indicates low viscosity, good fluidity, and good internal lubrication effect.

[0098] 2. Detection of external lubrication effect

[0099] The composite lubricants were prepared by the methods of Examples 1-8 and Comparative Examples 1-2 respectively. During the PVC melt extrusion process, the composite lubricant was added to PVC at a ratio of 0.5%. It was melt-extruded by a single-screw extruder. The temperature was: Zone 1: 100°C; Zone 2: 150°C; Zone 3: 190°C; Die head: 170°C; Rotation speed: 40 r / min. The surface smoothness of the extrudate was recorded and scored. The scoring criteria were as follows: High surface smoothness, no burrs, no obvious pits: 10 points → Severe surface roughness, severe burrs, severe pits: 1 point; And calculate the total area of pits with a diameter greater than 1 mm per unit area.

[0100] Table 1 Performance test table (" / " in the table represents that the corresponding example did not detect this item, so there is no data)

[0101]

[0102] Combined with Examples 1-3 and Table 1, it can be seen that the extrusion amount of the composite lubricant prepared in this application is relatively high. Even when processing polyvinyl chloride at a relatively high temperature, it still has a relatively high extrusion amount, indicating that the composite lubricant can reduce the internal cohesion of plastic molecules, reduce the melt viscosity, improve the fluidity, and facilitate extrusion molding; while the area of the rough surface is relatively small and the smoothness score is relatively high, indicating that the composite lubricant can form an oil film on the plastic surface, reduce the friction between the plastic and the machine, improve the external lubrication effect, and the finished composite lubricant has good internal and external lubrication effects. Even at a relatively high temperature, it also has a good lubrication effect.

[0103] Combined with Example 1 and Examples 4-8 and Table 1, it can be seen that in Example 4, the oleic acid amide prepared in Preparation Example 1 was replaced with commercially available oleic acid amide of the same mass in the raw materials. Compared with Example 1, the extrusion amount of the composite lubricant prepared in Example 4 was lower than that of Example 1, the area sum was larger than that of Example 1, and the score was lower than that of Example 1; it shows that the oleic acid amide treated with hydrochloric acid dopamine solution can improve the heat resistance of the oleic acid amide, and after amino treatment, it can further improve the external lubrication effect.

[0104] In Example 5, the lauric acid amide prepared in Preparation Example 4 was replaced with commercially available lauric acid amide of the same mass in the raw materials. Compared with Example 1, the extrusion amount of the composite lubricant prepared in Example 5 was lower than that of Example 1, the area sum was larger than that of Example 1, and the score was lower than that of Example 1; it shows that after the lauric acid amide is treated with graphite nanosheets, it can not only improve the high-temperature resistance effect, but also form a stable oil film on the plastic surface, and it is not easy to cause problems such as roughness and pits on the plastic surface due to high-temperature processing, and the surface smoothness is relatively high.

[0105] In the preparation process of lauramide in the raw materials of Example 6, when replacing graphene nanosheets with graphene nanosheet microparticles of the same mass, compared with Example 1, the extrusion amount of the composite lubricant prepared in Example 6 is lower than that in Example 1, and the area sum is larger than that in Example 1. It shows that the polyethylene glycol hydroxyl groups attached to the surface of graphene nanosheets facilitate the mutual adsorption and bonding with the amide groups of lauramide and oleamide, further improving the high-temperature lubrication effect of the composite lubricant, and ensuring that lauramide has good internal lubrication and external lubrication effects during the high-temperature processing of plastic products.

[0106] In the preparation process of the high-temperature resistant filler in Example 7, polyglutamic acid solution was not added. Compared with Example 1, the extrusion amount of the composite lubricant prepared in Example 7 is lower than that in Example 1, and the area sum is larger than that in Example 1. It shows that the amino and carboxyl groups in polyglutamic acid on the surface of hydroxyapatite whiskers and nano boron nitride improve the adsorption and connection effect between the high-temperature resistant filler and the amide groups in oleamide and lauramide, improve the lubrication effect of the internal lubrication network inside the plastic molecules, and improve the lubrication effect of the composite lubricant.

[0107] In the preparation process of the high-temperature resistant filler in Example 8, hydroxyapatite whiskers were not added. Compared with Example 1, the extrusion amount of the composite lubricant prepared in Example 8 is lower than that in Example 1, and the area sum is larger than that in Example 1. It shows that the traction effect of hydroxyapatite whiskers and the load-bearing effect of nano boron nitride further improve the stability of the oil film formed by the composite lubricant on the plastic surface, and it is not easy to have problems such as high-temperature oil film rupture and damage, improving the lubrication effect of the composite lubricant. At the same time, hydroxyapatite whiskers have good high-temperature resistance, which can further improve the stability of the oil film under high-temperature conditions, thereby improving the lubrication effect of the composite lubricant.

[0108] Combining Example 1 and Comparative Examples 1-2 and Table 1, it can be seen that in Comparative Example 1, lauramide and tung oil were not added to the raw materials. Compared with Example 1, the extrusion amount of the composite lubricant prepared in Comparative Example 1 is lower than that in Example 1, the area sum is larger than that in Example 1, and the score is lower than that in Example 1. It shows that oleamide and lauramide penetrate between the ions and inside the particles of the plastic resin, reducing the friction between plastics and the friction between plastics and processing equipment, making the prepared lubricant have both internal lubrication effect and external lubrication effect; and oleamide, lauramide and tung oil can form a lubricating film on the plastic surface, further improving the external lubrication effect.

[0109] In Comparative Example 2, high-temperature resistant filler and tung oil were not added. Compared with Example 1, the extrusion amount of the composite lubricant prepared in Comparative Example 2 is lower than that in Example 1, the area sum is larger than that in Example 1, and the score is lower than that in Example 1. It shows that the high-temperature resistant filler and tung oil cooperate to improve the high-temperature stability of the lubricant, and the surface is smooth, having good internal lubrication and external lubrication effects under the high-temperature conditions of plastic processing.

[0110] This specific embodiment is only an interpretation of the present application and does not limit the present application. After reading this specification, those skilled in the art can make modifications to this embodiment without creative contributions as needed, but as long as it is within the scope of the claims of the present application, it is protected by the patent law.

Claims

1. An environmentally friendly composite lubricant, characterized in that: The invention comprises the following raw materials in parts by weight: 30-40 parts of oleic acid amide, 10-20 parts of lauramide, 5-10 parts of tung oil, 20-35 parts of emulsifier, 1-3 parts of defoamer, 1-3 parts of high temperature resistant filler, 0.5-1 parts of antioxidant and 30-50 parts of water; The oleamide is prepared by the following method: Hot ethanol is added to the oleamide particles and stirred until the oleamide is completely dissolved to obtain a solution with a mass fraction of 2-7%, and then ultrasonically shaken for 5-10 minutes, and then a dopamine hydrochloride solution is added, and the mass ratio of the solution to the dopamine hydrochloride solution is 1:0.1-0.

25. After the reaction, the solution is separated and purified to obtain oleamide; Lauramide is prepared from lauramide melt and graphite nanosheets in a mass ratio of 1:0.05-0.15; The high temperature resistant filler is prepared from hydroxyapatite whisker, nano boron nitride and polyglutamic acid solution in a mass ratio of 1:1-2:0.5-1.

2. The environmentally friendly composite lubricant according to claim 1, characterized in that: The frequency of the ultrasonic oscillation treatment is 20-40 kHz, and the time is 5-10 min.

3. The environmentally friendly composite lubricant according to claim 1, characterized in that: The dopamine hydrochloride solution is a dopamine hydrochloride hot ethanol solution with a mass fraction of 1-5%.

4. The environmentally friendly composite lubricant according to claim 1, characterized in that: The graphite nanosheet is prepared by loading a polyethylene glycol solution on graphite nanosheet particles.

5. The environmentally friendly composite lubricant according to claim 1, characterized in that: The defoaming agent is polydimethylsiloxane.

6. The environmentally friendly composite lubricant according to claim 1, characterized in that: The antioxidant is antioxidant 1010.

7. The method for preparing an environmentally friendly composite lubricant according to any one of claims 1 to 6, characterized in that: The following steps are involved: S1. Weigh oleic acid amide, tung oil, emulsifier and water, mix them, heat them to 70-80°C, then add high temperature resistant filler, mix and stir evenly to obtain a primary mixture; S2. Add lauramide to the initial mixture, raise the temperature to 105-110°C, continue to stir evenly, and finally cool down, add defoamer and antioxidant, mix and stir evenly to obtain a finished lubricant.

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