CN112961725B

CN112961725B - Environment-friendly lubricating oil additive and preparation method thereof

Info

Publication number: CN112961725B
Application number: CN202110195973.5A
Authority: CN
Inventors: 张学旺; 黄传华
Original assignee: Shanghai Zhongqi Industrial Co ltd
Current assignee: Shanghai Zhongqi Industrial Co ltd
Priority date: 2021-02-21
Filing date: 2021-02-21
Publication date: 2022-11-22
Anticipated expiration: 2041-02-21
Also published as: CN112961725A

Abstract

The application relates to the technical field of lubricating oil additives, and particularly discloses an environment-friendly lubricating oil additive and a preparation method thereof. An environment-friendly lubricating oil additive is prepared from the following raw materials in parts by weight: 25-35 parts of base oil, 6.2-8.6 parts of nano aluminum oxide, 5-9 parts of vegetable wax, 0.8-2.4 parts of benzotriazole and 5.2-7.6 parts of graphite, and has the advantages of environmental protection and no pollution; the preparation method comprises the following steps: 1) Weighing the base oil, the nano-alumina, the vegetable wax, the benzotriazole and the graphite in parts by weight; 2) And adding the base oil into a stirring container, then sequentially adding the nano-alumina, the vegetable wax, the benzotriazole and the graphite, heating, stirring and uniformly mixing to obtain the environment-friendly lubricating oil additive, wherein the environment-friendly lubricating oil additive has the advantage of simple operation.

Description

Environment-friendly lubricating oil additive and preparation method thereof

Technical Field

The application relates to the technical field of lubricating oil additives, in particular to an environment-friendly lubricating oil additive and a preparation method thereof.

Background

The operation of the machine depends on the relative movement of the parts, which is necessarily accompanied by the generation of friction and wear, and the normal operation of the machine is affected by serious friction and wear. Lubrication is the most common and effective way to address frictional wear caused by machine operation. Under the action of lubricating oil, the lubricating oil can form a lubricating oil film while carrying away a large amount of friction heat and shoulder grinding, thereby reducing the abrasion of a friction pair. Because the lubricating oil is mostly used in severe working environments such as high temperature, high pressure and the like, after the lubricating oil is used for a period of time, impurities such as carbon black, organic acid, water and the like are generated due to physical or chemical factors, so that the performance of the lubricating oil is changed and the lubricating oil cannot be used continuously.

Lubricating oil additives are often added to lubricating oils in order to improve the performance and extend the life of the lubricating oil. The traditional lubricating oil additive mostly adopts compounds with sulfur and phosphorus as main components, and the additive has excellent functions of resisting oxygen, corrosion, wear, extreme pressure and the like, but the use of the additive can generate air pollution and is not suitable for being used as the lubricating oil additive.

Disclosure of Invention

In order to overcome the defect that the existing lubricating oil additive has a pollution problem, the application provides an environment-friendly lubricating oil additive and a preparation method thereof.

In a first aspect, the present application provides an environment-friendly lubricating oil additive, which adopts the following technical scheme:

an environment-friendly lubricating oil additive is prepared from the following raw materials in parts by weight: 25-35 parts of base oil, 6.2-8.6 parts of nano-alumina, 5-9 parts of vegetable wax, 0.8-2.4 parts of benzotriazole and 5.2-7.6 parts of graphite.

By adopting the technical scheme, the base oil is used as the main component of the lubricating oil additive, and is uniformly mixed with other components of the lubricating oil additive and then added into the lubricating oil, so that the fusion effect between the lubricating oil additive and the lubricating oil can be improved, and the lubricating oil additive is more uniformly dispersed in the lubricating oil; the nano-alumina has good wear resistance, has small particle size, can be filled in the dent of the friction surface, thereby improving the friction coefficient of the friction surface, enhancing the lubricating property of the lubricating oil, and in addition, along with the running of a machine, the lubricating oil additive is continuously rubbed, so that the nano-alumina generates electrostatic adsorption, thereby forming a protective film on the friction surface, and further improving the lubricating property of the lubricating oil; the vegetable wax has the advantages of low toxicity, low pollution and biodegradability, is dispersed in the lubricating oil additive, has better wear resistance, and can effectively reduce the mechanical wear; the benzotriazole has good thermal stability, corrosion resistance and abrasion resistance, so that the thermal stability, corrosion resistance and abrasion resistance of the lubricating oil additive and the lubricating oil are improved; the graphite has good lubricating property and wear resistance, is dispersed in a lubricating oil additive and lubricating oil, and can improve the comprehensive performance of the lubricating oil: the lubricating oil additive does not contain sulfur-containing and phosphorus-containing compounds, almost has no pollution to the environment, is safe and environment-friendly, and is suitable for large-scale use.

Preferably, the base oil comprises one or more of methyl borate, gasoline, palm oil.

By adopting the technical scheme, the methyl borate, the gasoline and the palm oil have good lubricating and wear-resisting properties, and the high-temperature resistance properties of the methyl borate, the gasoline and the palm oil are excellent, so that the high-temperature resistance and the wear-resisting properties of the lubricating oil additive are excellent.

Preferably, the base oil is a mixture of methyl borate, gasoline and palm oil in a weight ratio of (1.1-1.3) to (0.4-0.6) to (3-5).

By adopting the technical scheme, the base oil with excellent performance can be obtained by mixing the methyl borate, the gasoline and the palm oil in a proper proportion range, and then the lubricating oil additive with excellent performance is prepared.

Preferably, the nano alumina needs to be modified, and the modification treatment comprises the following steps: 1) Uniformly mixing the nano alumina and 10-12 times of anhydrous ethanol by weight, and ultrasonically dispersing the mixture for 50-70imn to obtain a mixed solution I; 2) Adding a coupling agent accounting for 0.2-0.3 time of the weight of the nano aluminum oxide into the mixed solution I, and carrying out ultrasonic mixing for 10-20min to obtain a mixed solution II; 3) Adding the mixed solution II, adding 3-5mol/L hydrochloric acid solution until the pH value of the mixed solution II is 3-5, and heating to 60-70 ℃ to obtain mixed solution III; 4) And cooling the mixed solution III to room temperature, filtering, and drying filter residues obtained by filtering to obtain the modified nano aluminum oxide.

By adopting the technical scheme, firstly, the surface activity of the nano-alumina can be improved by using the absolute ethyl alcohol, so that the subsequent modification treatment of the nano-alumina is facilitated; then adding the coupling agent into the first mixed solution, and uniformly dispersing the coupling agent in the first mixed solution by using an ultrasonic mixing mode; adjusting the pH of the mixed solution II within an acidic range, promoting the fusion between the coupling agent and the nano alumina, and finally filtering to obtain modified nano alumina; after the nano aluminum oxide is modified, the coupling agent can be adhered to the surface of the nano aluminum oxide, so that the problem that the nano aluminum oxide is easy to agglomerate is solved, and the nano aluminum oxide can be uniformly dispersed in the lubricating oil additive.

Preferably, the coupling agent is a titanate coupling agent.

By adopting the technical scheme, the titanate coupling agent contains both the hydrophilic inorganic group and the hydrophilic organic group, so that the nano aluminum oxide is modified by using the titanate coupling agent, the hydrophilic inorganic group on the titanate coupling agent can be connected with the nano aluminum oxide, and the hydrophilic organic group is exposed, so that the modified nano aluminum oxide is added into the lubricating oil additive and can be connected with the organic matter component in the lubricating oil additive, the nano aluminum oxide can be uniformly dispersed, and the problem that the nano aluminum oxide is easy to agglomerate is solved.

Preferably, the particle size of the nano alumina is 300-400 meshes.

By adopting the technical scheme, the particle size of the nano alumina is selected within a proper range, so that the defect that the agglomeration problem is serious due to undersize nano alumina particle size is reduced; on the other hand, the problem that the performance of the lubricating oil additive is influenced due to obvious granularity of the lubricating oil additive caused by overlarge particle size of the nano alumina is solved.

Preferably, the plant wax is epidermal wax of any one of sugarcane, camphor and ginkgo.

By adopting the technical scheme, the plant epidermal wax of the sugarcane, the cinnamomum camphora and the ginkgo contains acid, alcohol and ester macromolecular organic matters, and has the advantages of biodegradability, environmental friendliness and renewability, and a lubricating oil film with high bearing capacity can be formed on the friction surface, so that the direct contact of the metal surface is prevented, and good antifriction performance is achieved.

In a second aspect, the present application provides a method for preparing an environment-friendly lubricating oil additive, which adopts the following technical scheme:

a preparation method of an environment-friendly lubricating oil additive comprises the following steps:

1) Weighing base oil, nano alumina, vegetable wax, benzotriazole and graphite in parts by weight;

2) And adding the base oil into a stirring container, then sequentially adding the nano-alumina, the vegetable wax, the benzotriazole and the graphite, heating, stirring and uniformly mixing to obtain the environment-friendly lubricating oil additive.

By adopting the technical scheme, the lubricating oil additive is prepared by using the method, the operation mode is simple, and the production efficiency is high, so that the method is suitable for batch production.

Preferably, in the step 2), the heating temperature is 65-73 ℃, and the stirring speed is 100-140r/min.

By adopting the technical scheme, the technological parameters in the production process of the lubricating oil additive are set within a reasonable range, and the lubricating oil additive with better performance can be prepared.

In summary, the present application has the following beneficial effects:

1. the nano-alumina has good wear resistance, has small particle size, can be filled in the dents of the friction surface, thereby improving the friction coefficient of the friction surface, enhancing the lubricating property of the lubricating oil, and in addition, along with the running of a machine, the lubricating oil additive is continuously rubbed, so that the nano-alumina generates electrostatic adsorption, thereby forming a protective film on the friction surface, and further improving the lubricating property of the lubricating oil; the vegetable wax has the advantages of low toxicity, low pollution and biodegradability, is dispersed in the lubricating oil additive, has better wear resistance, and can effectively reduce the mechanical wear; the benzotriazole has good thermal stability, corrosion resistance and abrasion resistance, so that the thermal stability, corrosion resistance and abrasion resistance of the lubricating oil additive and the lubricating oil are improved; the graphite has good lubricity and wear resistance, and can be dispersed in a lubricating oil additive and lubricating oil to improve the comprehensive performance of the lubricating oil: the lubricating oil additive does not contain sulfur-containing and phosphorus-containing compounds, almost has no pollution to the environment, is safe and environment-friendly, and is suitable for large-scale use.

2. The methyl borate, the gasoline and the palm oil have good lubricating and wear-resisting properties, and the high-temperature resistance of the methyl borate, the gasoline and the palm oil is excellent, so that the high-temperature resistance and the wear-resisting properties of the lubricating oil additive are excellent.

3. The titanate coupling agent contains both hydrophilic and inorganic groups, so that the nano-alumina is modified by the titanate coupling agent, the hydrophilic and inorganic groups on the titanate coupling agent can be connected with the nano-alumina, and the hydrophilic and organic groups are exposed, so that the modified nano-alumina is added into the lubricating oil additive and can be connected with organic matter components in the lubricating oil additive, the nano-alumina can be uniformly dispersed, and the problem that the nano-alumina is easy to agglomerate is solved.

Detailed Description

The present application will be described in further detail with reference to examples.

Source of raw materials

Name of raw materials	Manufacturer of the product	Model/specification
			Nano alumina	Beijing German Kagaku island gold science and technology Co Ltd	DK410-1
Boric acid methyl ester	Wuhan Fuxin Yuanjin Tech Co Ltd	Purity of 99%
			Gasoline (gasoline)	Sinopec Corporation	93# gasoline
Palm oil	Chemical Co., ltd of Jinan Boao	Commodity number 01
			Titanate coupling agent	Nanjing Yopu chemical Co., ltd	UP-101
Silane coupling agent	Nanjing prefecture chemical Co Ltd	KH-560

Preparation example of Nano alumina

Preparation example 1 with base oil 25-35kg, nanometer alumina 6.2-8.6kg, vegetable wax 5-9kg, benzotriazole 0.8-2.4kg and graphite 5.2-7.6kg

The modification treatment of the nano alumina comprises the following steps:

1) Uniformly mixing 30kg of nano alumina and 330kg of absolute ethyl alcohol, and ultrasonically dispersing 60imn to obtain a first mixed solution;

2) Adding 7.5kg of titanate coupling agent into the mixed solution I, and carrying out ultrasonic mixing for 15min to obtain mixed solution II;

3) Adding the mixed solution II, adding a 4mol/L hydrochloric acid solution until the pH value of the mixed solution II is 4, and heating to 65 ℃ to obtain a mixed solution III;

4) And cooling the mixed solution III to room temperature, filtering, and drying filter residues obtained by filtering to obtain the modified nano aluminum oxide.

Preparation example 2

The modification treatment of the nano alumina comprises the following steps:

1) Uniformly mixing 30kg of nano alumina and 300kg of absolute ethyl alcohol, and ultrasonically dispersing 50imn to obtain a first mixed solution;

2) Adding 6kg of titanate coupling agent into the mixed solution I, and carrying out ultrasonic mixing for 10min to obtain mixed solution II;

3) Adding the mixed solution II, then adding a 3mol/L hydrochloric acid solution until the pH value of the mixed solution II is 3, and then heating to 60 ℃ to obtain a mixed solution III;

Preparation example 3

The modification treatment of the nano aluminum oxide comprises the following steps:

1) Uniformly mixing 30kg of nano alumina and 360kg of absolute ethyl alcohol, and ultrasonically dispersing 70imn to obtain a first mixed solution;

2) Adding 9kg of titanate coupling agent into the mixed solution I, and ultrasonically mixing for 20min to obtain mixed solution II;

3) Adding the mixed solution II, adding a 5mol/L hydrochloric acid solution until the pH value of the mixed solution II is 5, and heating to 70 ℃ to obtain a mixed solution III;

4) And cooling the mixed solution III to room temperature, filtering, and drying filter residues obtained by filtering to obtain the modified nano-alumina.

Preparation example 4

The difference between the preparation example and the preparation example 1 is that: the coupling agent is selected from silane coupling agents.

Examples

Example 1

An environment-friendly lubricating oil additive is composed of the following raw materials by mass: 30kg of base oil, 7.4kg of nano-alumina, 7kg of vegetable wax, 1.6kg of benzotriazole and 5.4kg of graphite;

wherein the base oil is a mixture of methyl borate, gasoline and palm oil with the weight parts ratio of 1.2; the grain diameter of the nano alumina is 350mm; the plant wax is epidermal wax of sugarcane; the nano alumina in preparation example 1 is selected as the nano alumina.

The preparation method of the environment-friendly lubricating oil additive comprises the following steps:

1) Weighing 30kg of base oil, 7.4kg of nano-alumina, 7kg of vegetable wax, 1.6kg of benzotriazole and 5.4kg of graphite;

2) Adding the base oil into a stirring kettle, then sequentially adding the nano-alumina, the vegetable wax, the benzotriazole and the graphite, heating to 69 ℃, and stirring and mixing uniformly at a stirring speed of 120r/min to obtain the environment-friendly lubricating oil additive.

Example 2

An environment-friendly lubricating oil additive which is different from that in example 1 in that: the composite material is prepared from the following raw materials in parts by mass: 25kg of base oil, 6.2kg of nano-alumina, 5kg of vegetable wax, 0.8kg of benzotriazole and 5.2kg of graphite.

1) Weighing 25kg of base oil, 6.2kg of nano-alumina, 5kg of vegetable wax, 0.8kg of benzotriazole and 5.2kg of graphite;

2) Adding the base oil into a stirring kettle, then sequentially adding the nano-alumina, the vegetable wax, the benzotriazole and the graphite, heating to 65 ℃, and stirring and mixing uniformly at a stirring speed of 100r/min to obtain the environment-friendly lubricating oil additive.

Example 3

An environment-friendly lubricating oil additive, which is different from that in example 1 in that: the composite material is prepared from the following raw materials in parts by mass: 35kg of base oil, 8.6kg of nano-alumina, 9kg of vegetable wax, 2.4kg of benzotriazole and 7.6kg of graphite.

1) Weighing 35kg of base oil, 5.6kg of nano-alumina, 9kg of vegetable wax, 2.4kg of benzotriazole and 7.6kg of graphite;

2) And adding the base oil into a stirring kettle, then sequentially adding the nano-alumina, the vegetable wax, the benzotriazole and the graphite, heating to 73 ℃, and stirring and mixing uniformly at a stirring speed of 140r/min to obtain the environment-friendly lubricating oil additive.

Example 4

This embodiment is different from embodiment 1 in that: the base oil is a mixture of methyl borate, gasoline and palm oil with the weight ratio of 1.1.

Example 5

This embodiment is different from embodiment 1 in that: the base oil is a mixture of methyl borate, gasoline and palm oil with the weight ratio of 1.3.

Example 6

This embodiment is different from embodiment 1 in that: the base oil is a mixture of methyl borate, gasoline and palm oil with the weight ratio of 1.

Example 7

The present embodiment is different from embodiment 1 in that: the base oil is a mixture of methyl borate, gasoline and palm oil in a ratio of 1.4 parts by weight.

Example 8

The present embodiment is different from embodiment 1 in that: the grain diameter of the nano alumina is 300mm.

Example 9

This embodiment is different from embodiment 1 in that: the grain diameter of the nano-alumina is 400mm.

Example 10

This embodiment is different from embodiment 1 in that: the grain diameter of the nano alumina is 250mm.

Example 11

This embodiment is different from embodiment 1 in that: the grain diameter of the nano alumina is 450mm.

Example 12

The present embodiment is different from embodiment 1 in that: the vegetable wax is epidermal wax of Cinnamomum camphora.

Example 13

This embodiment is different from embodiment 1 in that: the vegetable wax is epidermal wax of semen Ginkgo.

Example 14

This embodiment is different from embodiment 1 in that: the nano alumina in preparation example 2 is selected as the nano alumina.

Example 15

This embodiment is different from embodiment 1 in that: the nano alumina in preparation example 3 is selected as the nano alumina.

Example 16

This embodiment is different from embodiment 1 in that: the nano alumina in preparation example 4 is selected as the nano alumina.

Example 17

This embodiment is different from embodiment 1 in that: the nano-alumina is not modified.

Comparative example

Comparative example 1

The comparative example differs from example 1 in that: the raw material composition does not contain nano alumina.

Comparative example 2

This comparative example differs from example 1 in that: the raw material composition does not contain vegetable wax.

Performance test

Respectively taking 3g of the lubricating oil additives prepared in the examples 1-17 and the comparative examples 1-2, adding the lubricating oil additives into 97g of lubricating oil, and stirring and mixing uniformly to obtain a sample; the samples were then tested for the following properties and the results are reported in table 1.

1. The kinematic viscosity, low-temperature kinematic viscosity and high-temperature shear viscosity of each sample of lubricating oil were measured and tested according to the standard regulation of GB/11121-2006 (gasoline engine oil).

2. The anti-wear performance of each sample of lubricating oil was specified according to the standard of GB/T3142-1982 (determination of bearing capacity of lubricant (four-ball method)).

The test conditions were: 11-grade steel balls with the diameter of 12.7mm, the hardness of HRC59-61, the material of GCr15, the rotating speed of 1450 revolutions per minute and the time of 10s.

3. The oxidation resistance of each sample lubricating oil is specified according to the standard of SH/T0193-2008 "measurement of oxidation stability of lubricating oil-rotating oxygen bomb method".

TABLE 1 Performance test Table

1. The results of the performance tests of examples 1 to 3 show that: all performances of the three groups of samples are excellent, which shows that all performances of the environment-friendly lubricating oil additive prepared by the raw material composition and the method are excellent;

2. according to the performance test results of the embodiment 1 and the embodiments 4 to 7, the following results can be obtained: the properties of examples 1, 4 and 5 are superior to those of examples 6 and 7 because: when the mixture of the methyl borate, the gasoline and the palm oil with the ratio of the amount of the base oil to the parts by weight of (1.1-1.3) to (0.4-0.6) to (3-5) is selected, the mixture ratio of the methyl borate, the gasoline and the palm oil is in a proper range, the base oil with excellent performance can be obtained, and the lubricating oil additive with excellent performance can be further prepared;

3. according to the performance test results of the embodiment 1 and the embodiments 8-11, it can be seen that: the properties of examples 1, 8 and 9 are superior to those of examples 10 and 11 because: the particle size of the nano alumina is selected in a proper range, so that the defect that the agglomeration problem is serious due to undersize nano alumina particle size is reduced; on the other hand, the problem that the performance of the lubricating oil additive is influenced due to obvious granularity of the lubricating oil additive caused by overlarge particle size of the nano alumina is solved;

4. according to the performance test results of the embodiment 1 and the embodiments 12 to 13, the following results can be obtained: the properties of example 1 are superior to those of examples 12 and 13 because: the plant epidermal wax of the sugarcane, the cinnamomum camphora and the ginkgo contains acid, alcohol and ester macromolecular organic matters, has the advantages of biodegradability, environmental friendliness and renewability, can form a lubricating oil film with high bearing capacity on a friction surface, prevents the metal surface from directly contacting, and has good antifriction performance;

5. according to the performance test results of the embodiment 1 and the embodiments 14 to 16, it can be seen that: the properties of examples 1, 14 and 15 are superior to those of example 16 because: the titanate coupling agent contains both inorganic groups and organic groups, so that the nano alumina is modified by the titanate coupling agent, the inorganic groups on the titanate coupling agent can be connected with the nano alumina, and the organic groups are exposed, so that the modified nano alumina is added into the lubricating oil additive and can be connected with organic matter components in the lubricating oil additive, the nano alumina can be uniformly dispersed, and the problem that the nano alumina is easy to agglomerate is solved;

6. according to the performance test results of the embodiment 1 and the embodiment 17, it can be seen that: the properties of example 1 are superior to those of example 17 because: after the nano aluminum oxide is modified, the coupling agent can be adhered to the surface of the nano aluminum oxide, so that the problem that the nano aluminum oxide is easy to agglomerate is solved, and the nano aluminum oxide can be uniformly dispersed in the lubricating oil additive;

7. according to the performance test results of the example 1 and the comparative example 1, the following results can be obtained: the properties of examples 1, 4 and 5 are superior to those of comparative example 1 because: the nano-alumina has good wear resistance, has small particle size, can be filled in the dents of the friction surface, thereby improving the friction coefficient of the friction surface, enhancing the lubricating property of the lubricating oil, and in addition, along with the running of a machine, the lubricating oil additive is continuously rubbed, so that the nano-alumina generates electrostatic adsorption, thereby forming a protective film on the friction surface, and further improving the lubricating property of the lubricating oil;

8. according to the performance test results of the example 1 and the comparative example 2, the following results can be obtained: the properties of examples 1, 4 and 5 are superior to those of comparative example 2 because: the vegetable wax has the advantages of low toxicity, low pollution and biodegradability, is dispersed in the lubricating oil additive, has good wear resistance, and can effectively reduce the mechanical wear.

The specific embodiments are merely illustrative of the present application and not restrictive, and those skilled in the art who review this disclosure may make modifications to the embodiments as needed without any inventive contribution, but fall within the scope of the claims of the present application.

Claims

1. An environment-friendly lubricating oil additive, which is characterized in that: the feed is prepared from the following raw materials in parts by weight: 25-35 parts of base oil, 6.2-8.6 parts of nano aluminum oxide, 5-9 parts of vegetable wax, 0.8-2.4 parts of benzotriazole and 5.2-7.6 parts of graphite;

the base oil is a mixture of methyl borate, gasoline and palm oil in the weight ratio of (1.1-1.3) to (0.4-0.6) to (3-5);

the plant wax is epidermal wax of any one of sugarcane, camphor and ginkgo.

2. The environmentally friendly lubricating oil additive of claim 1, wherein: the nano aluminum oxide needs to be modified, and the modification treatment comprises the following steps: 1) Uniformly mixing nano alumina in parts by weight and 10-12 times of absolute ethyl alcohol in parts by weight of nano alumina, and ultrasonically dispersing 50-70imn to obtain a first mixed solution; 2) Adding a coupling agent accounting for 0.2-0.3 time of the weight of the nano aluminum oxide into the mixed solution I, and carrying out ultrasonic mixing for 10-20min to obtain a mixed solution II; 3) Adding the mixed solution II, adding 3-5mol/L hydrochloric acid solution until the pH value of the mixed solution II is 3-5, and heating to 60-70 ℃ to obtain mixed solution III; 4) And cooling the mixed solution III to room temperature, filtering, and drying filter residues obtained by filtering to obtain the modified nano-alumina.

3. The environmentally friendly lubricating oil additive of claim 2, wherein: the coupling agent is a titanate coupling agent.

4. The environmentally friendly lubricating oil additive of claim 1, wherein: the grain diameter of the nano alumina is 300-400 meshes.

5. A method for preparing the environmentally friendly lubricating oil additive according to any one of claims 1 to 4, wherein: the method comprises the following steps:

6. The method of claim 5, wherein the lubricant additive is prepared by the following steps: in the step 2), the heating temperature is 65-73 ℃, and the stirring speed is 100-140r/min.