CN111621135B

CN111621135B - Application of carbamate compound as polyurethane lubricant

Info

Publication number: CN111621135B
Application number: CN201910145842.9A
Authority: CN
Inventors: 杨万庆; 黄岐善
Original assignee: Wanhua Chemical Group Co Ltd; Wanhua Chemical Ningbo Co Ltd
Current assignee: Wanhua Chemical Group Co Ltd; Wanhua Chemical Ningbo Co Ltd
Priority date: 2019-02-27
Filing date: 2019-02-27
Publication date: 2022-08-05
Anticipated expiration: 2039-02-27
Also published as: CN111621135A

Abstract

本发明公开了一种氨基甲酸酯化合物作为聚氨酯润滑剂的应用，该氨基甲酸酯化合物是由二异氰酸酯和含有单羟基的单官能度脂肪族化合物反应制得，具有与热塑性聚氨酯相容性优异、不析出、防粘和润滑效果突出的特点，可用于改善聚氨酯产品粘连、不易脱模的市场应用。The invention discloses the application of a urethane compound as a polyurethane lubricant. The urethane compound is prepared by reacting a diisocyanate and a monofunctional aliphatic compound containing a monohydroxy group, and has compatibility with thermoplastic polyurethane. It has the characteristics of excellent, no precipitation, outstanding anti-sticking and lubricating effects, and can be used for market applications where polyurethane products are not easy to be released from the mold.

Description

Application of carbamate compound as polyurethane lubricant

Technical Field

The invention discloses an application of a carbamate compound as a polyurethane lubricant, wherein the carbamate compound is prepared by reacting diisocyanate with an aliphatic compound containing monofunctional hydroxyl. The polyurethane lubricating grease has the characteristics of excellent compatibility with thermoplastic polyurethane, no precipitation, outstanding anti-sticking and lubricating effects, and can be applied to the market for improving the adhesion of polyurethane products and preventing demoulding easily.

Background

The polyurethane is a polymer containing a carbamate group in a molecular main chain, generally comprises polyester type and polyether type, has high mechanical strength, flexibility, wear resistance, oil resistance and other excellent performances, is processed and molded in various modes, and is widely applied to the market.

The polyurethane material has strong viscosity due to the existence of strong polar isocyanate structural groups and polyester or polyether flexible chain segment structures in the molecular structure of the polyurethane, and is not favorable for certain market applications. For example, polyurethane elastomers stick to a mold in the processes of injection molding, calendering and the like, and are difficult to demould; the problem that the opening is not easy to occur after the polyurethane coiled material or the film is rolled; the demoulding of the casting polyurethane elastomer and the polyurethane foaming material is difficult in the forming process.

CN 105504222A discloses a thermoplastic polyurethane elastomer (TPU) material special for a high-transparency mobile phone shell sheath and a preparation method thereof, wherein 0.1-0.6% of a lubricant is added for realizing good demoulding of the TPU, and the lubricant is one or a mixture of more of stearic acid amide, montan wax, oleic acid amide or ethylene bis-stearic acid amide. US3595827A self-lubricating composition is disclosed wherein the lubricant has the structure R ₁ -CONH-R ₂ The compound is added in an amount of 0.02 to 1%. US3562291 discloses a combination of erucamide and lauramide for anti-tack and self-lubricating of polymers. In addition, conventional pigments, filler dispersants such as ethylene bis stearamide and ethylene bis oleamide have problems with compatibility with polyurethanes, which leads to white bloom on the surface of the product. In summary, when used in polyurethane, polyolefin lubricants such as amide-based lubricants and montmorillonite waxes have problems of poor compatibility, blooming and oil bleeding, and the product quality, particularly the appearance quality, is greatly affected.

Disclosure of Invention

In view of the problems of the prior art, the present invention provides a use of a urethane compound as a polyurethane lubricant. The polyurethane coating has the characteristics of excellent compatibility with thermoplastic polyurethane, no precipitation, outstanding anti-sticking and lubricating effects, and can be used for improving the adhesion of polyurethane products, preventing demoulding and improving the market application of pigment fillers dispersed in the polyurethane products.

The technical scheme of the invention is as follows:

the application of a carbamate compound as a polyurethane lubricant, wherein the carbamate compound is prepared by reacting the following raw materials:

1) an isocyanate compound having at least two functionalities;

2) a monofunctional aliphatic compound having a monohydroxy group.

Furthermore, the structural formula of the mono-hydroxyl-containing mono-functionality aliphatic compound is R-OH. The molecular weight range of the mono-hydroxyl-containing mono-functionality aliphatic compound is 70-2000 g/mol, and preferably 70-600 g/mol.

Further, R is a saturated aliphatic group having 4 to 32 carbon atoms, or an unsaturated aliphatic group having 4 to 32 carbon atoms and containing a single double bond or a non-conjugated double bond, preferably a saturated or unsaturated aliphatic group having 16 to 26 carbon atoms, and more preferably a saturated or unsaturated aliphatic group having 16 to 22 carbon atoms. Examples of the mono-hydroxy group-containing monofunctional aliphatic compound include one or more of behenyl alcohol, stearyl alcohol, lauryl alcohol, myristyl alcohol, palmityl alcohol, n-heptanol, decanol, and octacosanol.

The isocyanate compound is selected from one or more of aliphatic isocyanates and aromatic isocyanates, preferably 4,4 '-dicyclohexylmethane diisocyanate, isophorone diisocyanate, 1, 4-cyclohexane diisocyanate, 1, 6-hexamethylene diisocyanate, 4, 4' -dibenzyl diisocyanate, cyclohexane dimethylene diisocyanate, norbornane diisocyanate, methylcyclohexyl diisocyanate, toluene diisocyanate, diphenylmethylene diisocyanate, naphthalene diisocyanate, 1, 4-benzene diisocyanate, xylylene diisocyanate, tetramethylene-m-xylylene diisocyanate, dimethylbiphenyl diisocyanate, dimethyldiphenylmethane diisocyanate, 3,3 '-dimethoxybiphenyl, 4, 4' -diphenyl ether diisocyanate, 4-methyldiphenylmethane-3, 4-diisocyanate, 2,4 '-diphenylsulfide diisocyanate, diethylbenzene diisocyanate, 4, 4' -diphenylethane diisocyanate, p-phenylene diisocyanate, tolylene diisocyanate trimer, an adduct of tolylene diisocyanate and trimethylolpropane, 1, 6-hexamethylene diisocyanate trimer, 1, 6-hexamethylene diisocyanate biuret, isophorone diisocyanate trimer, an adduct of 1, 6-hexamethylene diisocyanate and trimethylolpropane, cyclohexanedimethylene diisocyanate trimer, triphenylmethane triisocyanate, dimethyltriphenylmethane tetraisocyanate, one or more kinds of L-lysine triisocyanate, further preferably diphenylmethylene diisocyanate, 1, 6-hexamethylene diisocyanate, isophorone diisocyanate, 4,4 '-dicyclohexylmethane diisocyanate, 4, 4' -dibenzyl diisocyanate, 1, 4-cyclohexane diisocyanate, 1, 4-phenylene diisocyanate, an adduct of toluene diisocyanate and trimethylolpropane, 1, 6-hexamethylene diisocyanate trimer, 1, 6-hexamethylene diisocyanate biuret, isophorone diisocyanate trimer, an adduct of 1, 6-hexamethylene diisocyanate and trimethylolpropane, triphenylmethane triisocyanate, dimethyltriphenylmethane tetraisocyanate, and L-lysine triisocyanate.

Preferably, the carbamate compound is prepared by the steps of:

1) the isocyanate and the mono-hydroxyl-containing mono-functionality aliphatic compound are added into a reaction kettle according to the formula amount, and the molar ratio of the isocyanic acid radical to the hydroxyl is 1: 1.001-1: 1.2, preferably 1: 1.01-1: 1.1.

2) And introducing nitrogen to replace air in the reaction kettle, and carrying out stirring reaction for 10-120 min at the temperature of 60-240 ℃, further optimizing the reaction condition to be 60-150 ℃, and carrying out stirring reaction for 30-90 min.

3) Vacuumizing to remove small molecular compounds, preferably controlling the NCO content to be lower than 50ppm, cooling and discharging to obtain the product.

In addition to this preparation process, reaction quenchers may also be added during the preparation (e.g. in step 3) to adjust the NCO content of the polyurethane lubricant, for example to an NCO content of less than 50 ppm.

The reaction quenching agent can be at least one of methanol, ethanol, propanol, butanol, ethylene glycol, 1, 4-butanediol, glycerol, pentaerythritol, n-pentanol, n-hexanol and n-heptanol, wherein methanol and ethanol are preferred.

In the step 3), the step of removing the small molecule compound by vacuum pumping may be performed by vacuum pumping to 0.005-0.02kPa (e.g. 0.01kPa), heating to 190-. The small molecular compound referred to herein is a monofunctional aliphatic compound containing a monohydroxy group which does not participate in the reaction.

All of the above chemicals are commercially available, e.g., warfarin, mikelin, alatin, etc.

In the present invention, the pressure of the vacuum degree is absolute pressure.

THE ADVANTAGES OF THE PRESENT INVENTION

The carbamate compound has the characteristics of excellent compatibility with thermoplastic polyurethane, no precipitation, anti-sticking and outstanding lubricating effect, can be used for improving the market application of polyurethane products in adhesion and difficult demoulding, and can improve the market application of the polyurethane products in dispersing or lubricating pigments and fillers.

Detailed Description

The present invention will be described in further detail with reference to specific embodiments, but it should not be construed that the scope of the present invention is limited to the following examples. Various substitutions and alterations can be made by those skilled in the art and by conventional means without departing from the spirit of the method of the invention described above.

Example 1

1) Adding 4, 4' -diphenyl methylene diisocyanate (Vanhua chemical, industrial grade) and behenyl alcohol (Sima-aldrich, 98%) into a reaction kettle according to the formula amount, wherein the molar ratio of isocyanic acid radical to hydroxyl in the formula is 1: 1.01.

2) And introducing nitrogen for 5min to replace the air in the reaction kettle. The reaction was set at 80 ℃ and stirred for 60 min.

3) Controlling the vacuum degree of the system to be 0.01kPa, gradually heating to 210 ℃, and keeping for 10min until no micromolecules are separated out. Cooling and discharging to obtain the product.

Example 2

1) 4, 4' -dicyclohexyl methane diisocyanate (Vanhua chemical, industrial grade) and lauryl alcohol (Tianjin Schyne, 99%) are added into a reaction kettle according to the formula amount, and the molar ratio of isocyanic acid radical to hydroxyl in the formula is 1: 1.12.

2) And introducing nitrogen for 5min to replace the air in the reaction kettle. The reaction was set at 70 ℃ and stirred for 90 min.

3) Controlling the vacuum degree of the system to be 0.01kPa, gradually heating to 190 ℃, and keeping for 15min until no micromolecules are separated out. Cooling and discharging to obtain the product.

Example 3

1) 4, 4' -dicyclohexylmethane diisocyanate (Vanhua chemical, industrial grade) and palmityl alcohol (Shanghai Michelin, 98%) are added into a reaction kettle according to the formula, and the molar ratio of isocyanic acid radical to hydroxyl in the formula is 1: 1.05.

3) Controlling the vacuum degree of the system to be 0.01kPa, gradually heating to 210 ℃, and keeping for 12min until no micromolecules are separated out. Cooling and discharging to obtain the product.

Example 4

1) Adding 4, 4' -dicyclohexylmethane diisocyanate (Vanhua chemical, industrial grade), stearyl alcohol (Michael, AR) and behenyl alcohol (Sima-aldrich, 98%) into a reaction kettle according to the formula amount, wherein the molar ratio of isocyanic acid radical to hydroxyl in the formula is 1: 1.02.

2) And introducing nitrogen for 5min to replace the air in the reaction kettle. The reaction was set at 75-95 ℃ and stirred for 45 min.

3) The n-butanol, a quencher, was added while the NCO value of the reaction was checked to make the content below 50 ppm.

4) Controlling the vacuum degree of the system to be 0.01kPa, gradually heating to 220 ℃, and keeping for 10min until no micromolecules are separated out. Cooling and discharging to obtain the product.

Example 5

1) 1, 6-hexamethylene diisocyanate (Vanhua chemical, industrial grade), palmityl alcohol (Shanghai Merlin, 98%) and stearyl alcohol (Merlin, AR) are added into a reaction kettle according to the formula, and the molar ratio of isocyanic acid radical to hydroxyl in the formula is 1: 1.2.

2) And introducing nitrogen for 5min to replace the air in the reaction kettle. The reaction was set at 60 ℃ and stirred for 60 min.

3) Adding a quenching agent ethanol dropwise, and simultaneously detecting the NCO value of the reactants to ensure that the content is lower than 50 ppm.

4) Controlling the vacuum degree of the system to be 0.01kPa, gradually heating to 200 ℃, and keeping for 10min until no micromolecules are separated out. Cooling and discharging to obtain the product.

Example 6

1) 1, 6-hexamethylene diisocyanate (Vanhua chemical, industrial grade), stearyl alcohol (Meclin, AR) and behenyl alcohol (carbofuran, 99%, available in the market) are added into a reaction kettle according to the formula, and the molar ratio of isocyanic acid radical to hydroxyl in the formula is 1: 1.05.

2) And introducing nitrogen for 5min to replace the air in the reaction kettle. The reaction was set at 75 ℃ and stirred for 60 min.

3) The quencher propanol was added dropwise while the NCO value of the reactants was checked to below 50 ppm.

Example 7

1) 1, 6-hexamethylene diisocyanate (Vanhua chemical, industrial grade), n-heptanol (Michael, 99%) and lauryl alcohol (Tianjin Schenchen, 99%) are added into a reaction kettle according to the formula amount, and the molar ratio of isocyanic acid radical to hydroxyl in the formula is 1: 1.15.

3) Controlling the vacuum degree of the system to be 0.01kPa, gradually heating to 220 ℃, and keeping for 10min until no micromolecule is separated out. Cooling and discharging to obtain the product.

Example 8

1) 1, 6-hexamethylene diisocyanate (Vanhua chemical, industrial grade) and octacosanol (Xian kang Nuo chemical, 98%) are added into a reaction kettle according to the formula amount, and the molar ratio of isocyanic acid radical to hydroxyl in the formula is 1: 1.01.

2) And introducing nitrogen for 5min to replace the air in the reaction kettle. The reaction was set at 105 ℃ and stirred for 60 min.

4) Controlling the vacuum degree of the system to be 0.01kPa, gradually heating to 240 ℃, and keeping for 10min until no micromolecules are separated out. Cooling and discharging to obtain the product.

Verification of the application of examples and comparative examples

The release force, peel force, sheet transparency, bleeding, etc. of the TPU were tested by adding ethylene bis stearamide (EBS jequirity), erucamide (Croda ER, uk), calcium stearate (sanyi SAK-CS-P), and montmorillonite wax (Clariant E) which are widely available on the market as comparative examples to a common commercially available 90A TPU (elastolan 690A) using a twin screw extruder. Using the urethane compounds described in this patent, as an example, the lubricant was added to a common commercially available 90A TPU (Elastollan 690A) in the same way. The specific embodiment is as follows:

the lubricants of the examples and comparative examples were thoroughly mixed with the TPU according to the formulation of table 1 and then granulated by high-shear mixing in an SHJ-42 twin-screw extruder from south kyo jiya extrusion equipment ltd, the temperature settings of the screws in the zones being: temperature in the first zone: the temperature of 180 ℃, the temperature of the second zone is 195 ℃, the temperature of the third zone is 210 ℃, the temperature of the fourth zone is 210 ℃, the temperature of the fifth zone is 205 ℃, the temperature of the sixth zone is 200 ℃, the temperature of the seventh zone is 200 ℃, the temperature of the eighth zone is 195 ℃, the temperature of the ninth zone is 190 ℃ and the temperature of the neck ring mold is 190 ℃. The feed rate was set at 35 rpm and the screw speed was set at 300 rpm.

The properties are given in the table below, based on 100% by mass of the thermoplastic polyurethane elastomer.

TABLE 1 anti-sticking lubricity test formula and test results for thermoplastic polyurethane elastomer

Note 1: the force at which the injection part was ejected from the mold was tested using a commercially available TPU (BASF Elastollan 690A), using an injection molding machine (Claus Murphy CX80-180) and a 2mm flat mold.

Note x 2: a0.2 mm film was formed using a commercially available TPU (BASF Elastollan 690A) using a casting machine, and the opening peel force was measured after winding. The reference standard is: ASTM-D3330-a.

Note x 3: a2 mm test piece was injection-molded using a commercially available TPU (BASF Elastollan 690A) by means of an injection molding machine (Haitian model M600A) and the mold roughness was 0.02 or less. And (5) placing the test piece in an oven at 70 ℃ for 48 hours, testing whether the surface of the test piece is dirty or not, and recording whether the glossiness is clean or not and whether precipitates exist or not if the surface of the test piece is obviously dirty. If foreign matters are obvious, recording as 'precipitation exists' or 'severe precipitation'; when the surface is clean, the light transmittance is measured by Diffison, EEL-57D, British, and the test reference is ASTM D1003.

The invention will be further illustrated by the use of the examples to prepare dyed products of thermoplastic polyurethane elastomers.

The thermoplastic polyurethane elastomer (TPU) used in the following comparative examples and examples was Wanhua chemical WHT-1590. Carbon black (commercially available model number Cabot V-9A32), titanium dioxide (commercially available model number Kemu R105), ultramarine blue (commercially available model number Nubiola EP19), phthalocyanine blue (commercially available model number BASF Heliogen 7090), and antioxidant (commercially available model number BASF Irganox 1010). The lubricants, pigment dispersants (compare examples 1-8 in Table 2, respectively) used as thermoplastic polyurethanes in examples 1-8; the comparative examples were selected from the common commercial PE wax (commercial model: HONEYWELL AC-6A), EBS (commercial model: Indonesian chemical P-130), calcium stearate (commercial model: SAK-CS-P). The formulation is given in the table below.

TABLE 2 dyeing formulation table for thermoplastic polyurethane elastomers

The main equipment for preparing the dyed products of thermoplastic polyurethane elastomers is the SHJ-42 twin screw extruder from south kyo jiya extrusion equipment ltd. The processing and preparation method is as follows. The examples and comparative examples were thoroughly mixed according to the formulation of table 2 and then granulated by high-speed shear mixing therein, the temperatures of the zones of the screw being set to: temperature in the first zone: the temperature of 180 ℃, the temperature of 190 ℃ in the second zone, 200 ℃ in the third zone, 205 ℃ in the fourth zone, 200 ℃ in the fifth zone, 195 ℃ in the sixth zone, 195 ℃ in the seventh zone, 190 ℃ in the eighth zone, 185 ℃ in the ninth zone and 180 ℃ in the neck mold. The feed rate was set at 60 rpm and the screw speed was set at 300 rpm.

The test results are given in the table below.

TABLE 3 dyeing Properties of thermoplastic polyurethane Elastomers

Note 1: the test was performed using a DATACOLOR D650 spectrophotometer.

Note x 2: color master batch 4 wt.% was added to E685A, and injection molded into flat test pieces using an injection molding machine (seaday model M600A) with a mold roughness below 0.02. And (5) placing the test piece in an oven at 70 ℃ for 48 hours, testing whether the surface of the test piece is dirty or not, and recording whether the glossiness is clean or not and whether precipitates exist or not if the surface of the test piece is obviously dirty. If there is a significant foreign object, it is recorded as "present"; if the surface is clean, the gloss is measured at an angle of 20 degrees, the test standard is ASTM D523, and the instrument for measuring the gloss is BYK4566 gloss instrument from Bick chemical Co.

Note x 3: color master batch 4 wt.% was added to E685A and injection molded into flat test specimens for use using an injection molding machine (haitian model M600A). A standard white test piece containing titanium white (0.4%) was prepared using E685A resin. The test piece of the standard sample and the white test piece were sandwiched between the plates, and subjected to heat treatment at 80 ℃/24 hours under a pressure of 2kPa (reference standard: DIN 53775, GB250-2008, GB251-2008) to measure the color difference of the standard sample with a spectrophotometer (DATACOLOR-D650), and the migration resistance color fastness was judged as shown in Table 2.

TABLE 4-5 Gray card Gray color Difference Standard grade

Note 4: a color masterbatch of 4 wt.% was added to E685A and cast into a film of 0.02 ± 0.005mm thickness using a single screw extruder (hai ja HRJSJ-40) and the dispersion was observed under a microscope. And counting the number of particles of 2um, 10um and more than 30 um. The dispersibility rating is as in table 3.

TABLE 5-5 pigment Dispersion rating

Through the test, compared with the conventional anti-sticking demolding auxiliary agent, the polyurethane elastomer pigment dispersing agent prepared by using the carbamate compound has the advantages of good anti-sticking effect, no precipitation, no influence on the transparency of a polyurethane product and the like, has the advantages of excellent pigment dispersing performance, strong pigment color developing capability and high surface glossiness, is an industrial direction of the polyurethane lubricant, the polyurethane anti-sticking auxiliary agent and the pigment dispersing agent for dyeing polyurethane, and has high market value.

The above-described embodiments are illustrative, but not restrictive, of the spirit of the invention, and any modifications, equivalents, and improvements made within the spirit and principles of the invention are intended to be included within the scope of the invention.

Claims

1. The use of a carbamate compound as a polyurethane lubricant, the carbamate compound being prepared by reacting:

1) an isocyanate compound having at least two functionalities;

2) a monofunctional aliphatic compound having a monohydroxy group;

the structural general formula of the mono-hydroxyl-containing mono-functionality aliphatic compound is R-OH, wherein R is a saturated aliphatic group with 16-32 carbon atoms, or an unsaturated aliphatic group with 16-32 carbon atoms and containing a single double bond or a non-conjugated double bond, or the mono-hydroxyl-containing mono-functionality aliphatic compound is lauryl alcohol or myristyl alcohol.

2. The use according to claim 1, wherein R is a saturated or unsaturated aliphatic group having 16 to 26 carbon atoms.

3. The use according to claim 2, wherein R is a saturated or unsaturated aliphatic group having 16 to 22 carbon atoms.

4. Use according to claim 1, wherein R-OH is selected from one or more of behenyl alcohol, stearyl alcohol, palmityl alcohol, and octacosyl alcohol.

5. Use according to claim 1, wherein the isocyanate compound is selected from one or more of aliphatic isocyanates and aromatic isocyanates.

6. The use according to claim 5, wherein the isocyanate compound is 4,4 '-dicyclohexylmethane diisocyanate, isophorone diisocyanate, 1, 4-cyclohexane diisocyanate, 1, 6-hexamethylene diisocyanate, 4, 4' -dibenzyl diisocyanate, cyclohexane dimethylene diisocyanate, norbornane diisocyanate, methylcyclohexyl diisocyanate, toluene diisocyanate, diphenylmethylene diisocyanate, naphthalene diisocyanate, 1, 4-benzene diisocyanate, xylylene diisocyanate, tetramethylene-m-xylylene diisocyanate, dimethylbiphenyl diisocyanate, dimethyldiphenylmethane diisocyanate, 3,3 '-dimethoxybiphenyl, 4, 4' -diphenyl ether diisocyanate, 4-methyldiphenylmethane-3, 4-diisocyanate, 2,4 '-diphenylsulfide diisocyanate, diethylbenzene diisocyanate, 4, 4' -diphenylethane diisocyanate, p-phenylene diisocyanate, tolylene diisocyanate trimer, an adduct of tolylene diisocyanate and trimethylolpropane, 1, 6-hexamethylene diisocyanate trimer, 1, 6-hexamethylene diisocyanate biuret, isophorone diisocyanate trimer, an adduct of 1, 6-hexamethylene diisocyanate and trimethylolpropane, cyclohexanedimethylene diisocyanate trimer, triphenylmethane triisocyanate, dimethyltriphenylmethane tetraisocyanate, L-lysine triisocyanate.

7. The use according to claim 6, wherein the isocyanate compound is one or more of diphenylmethylene diisocyanate, 1, 6-hexamethylene diisocyanate, isophorone diisocyanate, 4,4 '-dicyclohexylmethane diisocyanate, 4, 4' -dibenzyl diisocyanate, 1, 4-cyclohexane diisocyanate, 1, 4-phenylene diisocyanate, an adduct of toluene diisocyanate and trimethylolpropane, 1, 6-hexamethylene diisocyanate trimer, 1, 6-hexamethylene diisocyanate biuret, isophorone diisocyanate trimer, an adduct of 1, 6-hexamethylene diisocyanate and trimethylolpropane, triphenylmethane triisocyanate, dimethyltriphenylmethane tetraisocyanate, and L-lysine triisocyanate.

8. Use according to claim 1, characterized in that the carbamate compound is prepared by the following steps:

1) adding an isocyanate compound and a mono-hydroxyl-containing monofunctional aliphatic compound into a reaction kettle according to a formula amount, wherein the molar ratio of isocyanate to hydroxyl is 1: 1.001-1: 1.2;

2) introducing nitrogen to replace air in the reaction kettle, and stirring and reacting for 10-120 min at 60-240 ℃;

3) vacuumizing to remove small molecular compounds, cooling and discharging to obtain a product.

9. The use of claim 8, wherein in step 1), the molar ratio of isocyanate groups to hydroxyl groups is 1:1.01 to 1: 1.1; and/or the presence of a gas in the gas,

in the step 2), the reaction condition is 60-150 ℃, and the stirring is carried out for 30-90 min; and/or the presence of a gas in the gas,

in step 3), the NCO content is controlled to be less than 50 ppm.

10. Use according to claim 8 or 9, characterized in that a reaction quencher is also added during the preparation to adjust the NCO-content of the polyurethane lubricant.

11. The use according to claim 10, wherein the reaction quenching agent is at least one selected from the group consisting of methanol, ethanol, propanol, butanol, ethylene glycol, 1, 4-butanediol, glycerol, pentaerythritol, n-pentanol, n-hexanol, and n-heptanol.

12. Use according to claim 11, wherein the reaction quenching agent is selected from methanol and/or ethanol.

13. The use as claimed in claim 8 or 9, wherein in step 3), the step of removing the small molecule compound by vacuum is performed by vacuum pumping to 0.005-0.02kPa, heating to 190-250 ℃ and keeping for 5-20 min.