Polyurethane for doffing disc and preparation method thereof

Abstract

The invention relates to the field of polyurethane materials, in particular to polyurethane for a doffing disc and a preparation method of the polyurethane. The polyurethane for the doffing disc is prepared from the following raw materials: long-chain polyol, diisocyanate, an alcohol chain extender, an amine chain extender, an antioxidant and a wear-resistant additive. Wherein the amine chain extender comprises polyaspartic acid ester. The DIN abrasion rate of the prepared polyurethane material is lower than 15%, the strength retention rate is larger than 80%, and the polyurethane material is particularly suitable for being used as a doffing disc in outdoor cotton picking operation.

Description

Technical Field

[0001] The invention relates to the field of polyurethane materials, in particular to polyurethane for a doffing disk and a preparation method thereof. Background Art

[0002] As one of the core components of the cotton picker, the doffer disk can efficiently separate cotton from the plant. When the cotton picker is in operation, the spindle inside it will pull out the cotton fibers at a certain rotation speed; and the doffer disk plays an auxiliary role in doffer. The structure of the doffer disk is ingeniously designed, usually consisting of a series of carefully arranged circular discs, which tightly surround the rotating axis of the spindle. When the spindle rotates carrying the cotton fibers, the cotton will contact the surface of the doffer disk. In order to complete the separation task more efficiently, special textures or grooves are set on the surface of the doffer disk. This design greatly enhances the friction between the cotton fibers and allows the cotton to be smoothly "pulled" off the plant. In the prior art, reports on doffer disks usually focus on their component structures. For example, patent document CN105265098A discloses a doffer disk, but there are few reports on the material selection of the doffer disk.

[0003] Polyurethane is highly favored for its excellent wear resistance, suitable hardness and elasticity. In the high-intensity and high-frequency friction environment of cotton picking, polyurethane materials can maintain their stable performance for a long time and are not easy to wear. In addition, considering that cotton pickers usually work outdoors and face complex and changeable climatic conditions, polyurethane materials also show good temperature resistance and weather resistance, ensuring that the cotton picker can work normally in various harsh environments.

[0004] Although polyurethane doffer discs have many advantages, they still need to be replaced regularly in actual use due to factors such as high wear and tear and material aging during use. How to provide a highly weather-resistant and wear-resistant polyurethane for doffer discs has become a technical problem that urgently needs to be solved. Summary of the invention

[0005] In order to solve the above technical problems, the first aspect of the present invention provides a polyurethane for a doffing disk, the preparation raw materials of which include: long-chain polyols, diisocyanates, alcohol chain extenders, amine chain extenders, antioxidants, and wear-resistant additives.

[0006] As an implementable case, the raw materials for preparing the polyurethane for the cotton doffing disk include, by mass, 50-70 parts of long-chain polyols, 20-40 parts of diisocyanates, 5-10 parts of alcohol chain extenders, 1-5 parts of amine chain extenders, 0.1-1 parts of antioxidants, and 0.1-1 parts of wear-resistant additives.

[0007] As an implementable example, the long-chain polyol includes polyester polyol and / or polyether polyol.

[0008] As an implementable case, the polyester polyol includes: one of polycarbonate diol, polyethylene adipate glycol ester diol, and polycaprolactone diol (PCL).

[0009] As an implementable example, the polyether polyol includes: polytetramethylene ether glycol (PTMG) and / or polyethylene glycol.

[0010] Furthermore, the long-chain polyol includes: PCL or PTMG.

[0011] As an implementable case, the diisocyanate includes one or more of p-phenylene diisocyanate, dimethyl diphenyl diisocyanate, toluene diisocyanate, and 4,4'-diphenylmethane diisocyanate.

[0012] Furthermore, the diisocyanate is one of toluene diisocyanate and 4,4'-diphenylmethane diisocyanate.

[0013] Furthermore, the diisocyanate is 4,4'-diphenylmethane diisocyanate (MDI).

[0014] The isocyanate group (-N=C=O) in the MDI molecule has high reactivity and can undergo addition polymerization with the hydroxyl group (-OH) in the polyether polyol or polyester polyol to form a stable polyurethane structure. At the same time, the MDI molecule contains a benzene ring structure. The rigidity and stability of the benzene ring help to improve the hardness and strength of the polyurethane material, and also help to improve the weather resistance and wear resistance of the cotton removal disk. When MDI reacts with PTMG or PCL to prepare polyurethane, the polyurethane molecular chain contains both hard segments formed by MDI and soft segments formed by PTMG or PCL. The structure of alternating hard and soft segments helps to improve the wear resistance of the material, in which the hard segment mainly bears the strength and hardness of the material, while the soft segment gives the material elasticity and flexibility. At the same time, hydrogen bonds can be formed between the carbamate groups in the polyurethane molecules, which can further improve the cohesion and strength of the polyurethane material, and help to improve the wear resistance and weather resistance of the cotton removal disk.

[0015] As an implementable case, the alcohol chain extender includes: one of 1,3-butanediol, 1,4-butanediol, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,5-pentanediol, 1,4-cyclohexanedimethanol, and 1,6-hexanediol.

[0016] Furthermore, the alcohol chain extender is 1,4-butanediol.

[0017] As an implementable case, the amine chain extender includes: one of triethylenetetramine (TEPA), diethylenetriamine (DIPA), ethylenediamine (EDA), diethylenetriamine, 3,3-dichloro-4,4-diaminodiphenylmethanediamine (MOCA), and polyaspartic acid ester.

[0018] Furthermore, the amine chain extender is polyaspartic acid ester.

[0019] As a diisocyanate, MDI can react with the hydroxyl groups in long-chain polyols to form polyurethane prepolymers. As a compound containing active hydrogen, the hydroxyl groups of 1,4-butanediol can react with the isocyanate groups in the prepolymer to extend the molecular chain diffusion, thereby promoting the curing and forming of the polyurethane elastomer. However, the inventors found that the use of a single-component alcohol chain extender has limited improvement in the mechanical properties and weather resistance of the polyurethane material; therefore, polyaspartic acid ester is selected as an amine chain extender to be added to the raw material system. Polyaspartic acid ester has a unique molecular structure and chemical properties. The amino group in its molecular structure is surrounded by a spatial coronal steric hindrance environment. The special induction effect makes it show a "deceleration" effect during the reaction with isocyanate, thereby helping to control the reaction rate and crosslinking density of the polyurethane, thereby improving its mechanical strength. In addition, the molecular structure of polyaspartic acid ester is stable and is not easily affected by external environmental factors and chemical changes occur, which can further improve the chemical stability and weather resistance of the polyurethane material.

[0020] As an implementable case, the brands of the antioxidant include: one or more of Tinuvin PUR 866, SI Group AT 215, SI Group AT 168, Irganox 1010, Irganox 1076, ETHANOX 330, and Hostanox SE 10.

[0021] Furthermore, the brands of the antioxidant include: Irganox 1076 and ETHANOX 330, and the mass ratio of Irganox 1076 to ETHANOX 330 is (1-2):1.

[0022] During long-term use, polyurethane materials will be affected by oxygen, light, heat, nitrogen oxides in the air and other factors, gradually aging and losing their physical and chemical properties. The addition of antioxidants can capture free radicals, slow down or prevent the occurrence of oxidation reactions, thereby improving the weather resistance and service life of the cotton removal disc.

[0023] As an implementable case, the wear-resistant additive is wax powder, and the brands of wax powder include: one of Licowax Cmicro powder PM, Licowax E powder, Licowax C powder, and Licowax PE 520fine grain.

[0024] Furthermore, the brand of the wear-resistant additive is Licowax E powder.

[0025] The addition of Licowax E powder can significantly improve the wear resistance of polyurethane materials, mainly due to its unique lubricity and dispersibility, which can form a protective film on the surface of polyurethane materials and reduce the friction and wear on the surface of the doffer disc. In addition, Licowax E powder has a good demoulding effect. During the injection molding process of the doffer disc, it can make the product easier to be released from the mold, reducing the wear of the mold and the deformation of the doffer disc.

[0026] The second aspect of the present invention provides a method for preparing polyurethane for a doffing disk, comprising:

[0027] S1. Add long-chain polyols into a reactor, heat the reactor to 100-105°C, then add antioxidants and wear-resistant additives, stir and disperse, vacuum and degas at 100-110°C until all materials in the reactor are completely dissolved, turn off the vacuum and continue stirring, then reduce the temperature in the reactor to 70-80°C;

[0028] S2, adding diisocyanate into the reaction kettle and stirring and mixing, when the NCO% content in the system drops to 7-9%, stopping stirring to obtain a polyurethane prepolymer;

[0029] S3. Mix the alcohol chain extender and the amine chain extender, add them to the polyurethane prepolymer, mix and degas in a planetary mixer, pour into a mold, place the mold in an oven at 110-120° C. and vulcanize for 16-24 hours to obtain the product.

[0030] Beneficial Effects

[0031] (i) The present invention selects MDI and PTMG or PCL as the main raw materials for reaction to prepare polyurethane, which can further improve the cohesion and strength of the polyurethane material, and also helps to improve the wear resistance and weather resistance of the cotton doffing disc.

[0032] (ii) The present invention selects a compound of an alcohol chain extender and an amine chain extender, especially a compound of 1,4-butanediol and polyaspartic acid ester, which can further improve the chemical stability and weather resistance of the polyurethane material and can also improve the mechanical properties of the cotton doffing disc.

[0033] (III) In the present invention, antioxidants and wear-resistant additives are added to the raw materials for preparing the polyurethane for the doffing disk, so that the polyurethane material can have more excellent weather resistance and wear resistance.

[0034] (IV) The polyurethane material prepared by the present invention has a DIN abrasion rate lower than 15% and a strength retention rate greater than 80%, and has excellent practical use effects, and is particularly suitable for use as a doffer in outdoor cotton picking operations.

[0035] (V) When the polyurethane material prepared by the present invention is used as a doffing disc, due to its excellent weather resistance and mechanical properties, the number of replacement times of the doffing disc can be significantly reduced, thereby saving manpower and material resources and improving cotton picking efficiency. DETAILED DESCRIPTION

[0036] In the following implementation cases:

[0037] The PTMG is PLACCEL 230N, purchased from BASF AG.

[0038] The brand of PCL is PLACCEL 230N, which is purchased from Daicel (China) Investment Co., Ltd.

[0039] The TDI is of the brand HT-100, purchased from Wanhua Chemical Group Co., Ltd.

[0040] The brand of the MDI is Millionate MT, purchased from Tosoh Corporation of Japan.

[0041] The 1,4-butanediol was purchased from Mitsubishi Chemical Corporation of Japan.

[0042] The MOCA was purchased from Suzhou Xiangyuan New Materials Co., Ltd.

[0043] The grade of the polyaspartic acid ester is NH 1520 was purchased from Bayer (China) Co., Ltd.

[0044] The grade of the HDI trimer is N 3300, purchased from Bayer (China) Co., Ltd.

[0045] The TMP was purchased from Perstorp Group.

[0046] The antioxidant with the brand name of Irganox 1076 was purchased from BASF AG.

[0047] The antioxidant with the brand name ETHANOX 330 was purchased from SI Group Chemical (Shanghai) Co., Ltd.

[0048] The wear-resistant additive of brand Licowax E powder was purchased from Clariant Group.

[0049] Example 1

[0050] The first aspect of this example provides a polyurethane for a cotton doffing disk, and the raw materials for its preparation include, by weight: 62.4 parts of long-chain polyols, 29.5 parts of diisocyanates, 7.35 parts of alcohol chain extenders, 1.25 parts of amine chain extenders, 0.5 parts of antioxidants, and 0.5 parts of wear-resistant additives.

[0051] The long-chain polyol is PCL.

[0052] The diisocyanate is MDI.

[0053] The alcohol chain extender is 1,4-butanediol.

[0054] The amine chain extender is polyaspartic acid ester.

[0055] The brands of the antioxidants include Irganox 1076 and ETHANOX 330, and the mass ratio of the Irganox 1076 antioxidant to the ETHANOX 330 antioxidant is 3:2.

[0056] The grade of the wear-resistant additive is Licowax E powder.

[0057] The second aspect of this example provides a method for preparing polyurethane for a doffing disk, comprising:

[0058] S1. Add long-chain polyol into the reactor, heat the reactor to 105°C, then add antioxidant and wear-resistant additive, stir and disperse, vacuum and degas for 2h at 105°C until all materials in the reactor are completely dissolved, turn off the vacuum and continue stirring for 30min, then reduce the temperature in the reactor to 75°C;

[0059] S2, adding diisocyanate into the reaction kettle and stirring and mixing, when the NCO% content in the system drops to 8.8%, stopping stirring to obtain a polyurethane prepolymer;

[0060] S3. Mix the alcohol chain extender and the amine chain extender, add them to the polyurethane prepolymer, mix and degas in a planetary mixer for 30 seconds, then pour into a mold at 120°C, place the mold in an oven at 110°C and vulcanize for 16 hours to obtain the product.

[0061] Example 2

[0062] The first aspect of this example provides a polyurethane for a cotton doffing disk, and the raw materials for its preparation include, by weight: 63.3 parts of long-chain polyols, 29.4 parts of diisocyanates, 6.5 parts of alcohol chain extenders, 1.1 parts of amine chain extenders, 0.5 parts of antioxidants, and 0.5 parts of wear-resistant additives.

[0063] The long-chain polyol is PTMG.

[0064] The diisocyanate is MDI.

[0065] The alcohol chain extender is 1,4-butanediol.

[0066] The amine chain extender is polyaspartic acid ester.

[0067] The brands of the antioxidants include Irganox 1076 and ETHANOX 330; the mass ratio of the Irganox 1076 antioxidant to the ETHANOX 330 antioxidant is 3:2.

[0068] The grade of the wear-resistant additive is Licowax E powder.

[0069] The second aspect of this example provides a method for preparing polyurethane for a doffing disk, comprising:

[0070] S1. Add long-chain polyol into the reactor, heat the reactor to 105°C, then add antioxidant and wear-resistant additive, stir and disperse, vacuum and degas for 2h at 105°C until all materials in the reactor are completely dissolved, turn off the vacuum and continue stirring for 30min, then reduce the temperature in the reactor to 75°C;

[0071] S2, adding diisocyanate into the reaction kettle and stirring and mixing, when the NCO% content in the system drops to 7.8%, stopping stirring to obtain a polyurethane prepolymer;

[0072] S3. Mix the alcohol chain extender and the amine chain extender, add them to the polyurethane prepolymer, mix and degas in a planetary mixer for 30 seconds, then pour into a mold at 120°C, place the mold in an oven at 110°C and vulcanize for 16 hours to obtain the product.

[0073] Comparative Example 1

[0074] The first aspect of this example provides a polyurethane for a cotton doffing disk, and the raw materials for its preparation include, by weight: 62.1 parts of long-chain polyols, 17.6 parts of diisocyanates, 20.3 parts of amine chain extenders, 0.5 parts of antioxidants, and 0.5 parts of wear-resistant additives.

[0075] The long-chain polyol is PCL.

[0076] The diisocyanate is TDI.

[0077] The amine chain extender is MOCA.

[0078] The brands of the antioxidants include Irganox 1076 and ETHANOX 330, and the mass ratio of the Irganox 1076 antioxidant to the ETHANOX 330 antioxidant is 3:2.

[0079] The grade of the wear-resistant additive is Licowax E powder.

[0080] The second aspect of this example provides a method for preparing polyurethane for a doffing disk, comprising:

[0081] S1. Add long-chain polyol into the reactor, heat the reactor to 105°C, then add antioxidant and wear-resistant additive, stir and disperse, vacuum and degas for 2h at 105°C until all materials in the reactor are completely dissolved, turn off the vacuum and continue stirring for 30min, then reduce the temperature in the reactor to 75°C;

[0082] S2, adding diisocyanate into the reaction kettle and stirring and mixing, when the NCO% content in the system drops to 8.5%, stopping stirring to obtain a polyurethane prepolymer;

[0083] S3. Add an amine chain extender to the polyurethane prepolymer, mix and degas in a planetary mixer for 30 seconds, then pour into a mold at 120°C, place the mold in an oven at 110°C and vulcanize for 16 hours to obtain the product.

[0084] Comparative Example 2

[0085] The first aspect of this example provides a polyurethane for a doffing disk, and the raw materials for its preparation include, by weight: 64.5 parts of long-chain polyol, 17.9 parts of diisocyanate, 17.6 parts of amine chain extender, 0.5 parts of antioxidant, and 0.5 parts of wear-resistant additive.

[0086] The long-chain polyol is PTMG.

[0087] The diisocyanate is TDI.

[0088] The amine chain extender is MOCA.

[0089] The brands of the antioxidants include Irganox 1076 and ETHANOX 330, and the mass ratio of the Irganox 1076 antioxidant to the ETHANOX 330 antioxidant is 3:2.

[0090] The grade of the wear-resistant additive is Licowax E powder.

[0091] The second aspect of this example provides a method for preparing polyurethane for a doffing disk, comprising:

[0092] S1. Add long-chain polyol into the reactor, heat the reactor to 105°C, then add antioxidant and wear-resistant additive, stir and disperse, vacuum and degas for 2h at 105°C until all materials in the reactor are completely dissolved, turn off the vacuum and continue stirring for 30min, then reduce the temperature in the reactor to 75°C;

[0093] S2, adding diisocyanate into the reaction kettle and stirring and mixing, when the NCO% content in the system drops to 7.2%, stopping stirring to obtain a polyurethane prepolymer;

[0094] S3. Add an amine chain extender to the polyurethane prepolymer, mix and degas in a planetary mixer for 30 seconds, then pour into a mold at 120°C, place the mold in an oven at 110°C and vulcanize for 16 hours to obtain the product.

[0095] Comparative Example 3

[0096] The first aspect of this example provides a polyurethane for a doffing disk, and the raw materials for its preparation include, by weight: 60.3 parts of long-chain polyols, 31.6 parts of diisocyanates, 8.12 parts of alcohol chain extenders, 0.5 parts of antioxidants, and 0.5 parts of wear-resistant additives.

[0097] The long-chain polyol is PCL.

[0098] The diisocyanate is MDI.

[0099] The alcohol chain extender is 1,4-butanediol.

[0100] The brands of the antioxidants include Irganox 1076 and ETHANOX 330, and the mass ratio of the Irganox 1076 antioxidant to the ETHANOX 330 antioxidant is 3:2.

[0101] The grade of the wear-resistant additive is Licowax E powder.

[0102] The second aspect of this example provides a method for preparing polyurethane for a doffing disk, comprising:

[0103] S1. Add long-chain polyol into the reactor, heat the reactor to 105°C, then add antioxidant and wear-resistant additive, stir and disperse, vacuum and degas for 2h at 105°C until all materials in the reactor are completely dissolved, turn off the vacuum and continue stirring for 30min, then reduce the temperature in the reactor to 75°C;

[0104] S2, adding diisocyanate into the reaction kettle and stirring and mixing, when the NCO% content in the system drops to 8.8%, stopping stirring to obtain a polyurethane prepolymer;

[0105] S3. Add the alcohol chain extender to the polyurethane prepolymer, mix and degas in a planetary mixer for 30 seconds, then pour into a mold at 120°C, place the mold in an oven at 110°C and vulcanize for 16 hours to obtain the product.

[0106] Comparative Example 4

[0107] The first aspect of this example provides a polyurethane for a cotton doffing disk, and the raw materials for its preparation include, by weight: 62.4 parts of long-chain polyols, 29.5 parts of diisocyanates, 7.35 parts of alcohol chain extenders, 1.25 parts of curing agents, 0.5 parts of antioxidants, and 0.5 parts of wear-resistant additives.

[0108] The long-chain polyol is PCL.

[0109] The diisocyanate is MDI.

[0110] The alcohol chain extender is 1,4-butanediol.

[0111] The curing agent is HDI trimer.

[0112] The brands of the antioxidants include Irganox 1076 and ETHANOX 330, and the mass ratio of the Irganox 1076 antioxidant to the ETHANOX 330 antioxidant is 3:2.

[0113] The grade of the wear-resistant additive is Licowax E powder.

[0114] The second aspect of this example provides a method for preparing polyurethane for a doffing disk, comprising:

[0115] S1. Add long-chain polyol into the reactor, heat the reactor to 105°C, then add antioxidant and wear-resistant additive, stir and disperse, vacuum and degas for 2h at 105°C until all materials in the reactor are completely dissolved, turn off the vacuum and continue stirring for 30min, then reduce the temperature in the reactor to 75°C;

[0116] S2, adding diisocyanate into the reaction kettle and stirring and mixing, controlling the NCO% content of the system to be 8.8%, to obtain a polyurethane prepolymer;

[0117] S3. Mix the alcohol chain extender and curing agent, add them to the polyurethane prepolymer, mix and degas in a planetary mixer for 30 seconds, then pour into a mold at 120°C, place the mold in an oven at 110°C and vulcanize for 16 hours to obtain the product.

[0118] Comparative Example 5

[0119] The first aspect of this example provides a polyurethane for a cotton doffing disk, and the raw materials for its preparation include, by weight: 62.4 parts of long-chain polyols, 29.5 parts of diisocyanates, 7.35 parts of alcohol chain extenders, 0.5 parts of curing agents, 0.5 parts of antioxidants, and 0.5 parts of wear-resistant additives.

[0120] The long-chain polyol is PCL.

[0121] The diisocyanate is MDI.

[0122] The alcohol chain extender is 1,4-butanediol.

[0123] The curing agent is TMP (trimethylolpropane).

[0124] The brands of the antioxidants include Irganox 1076 and ETHANOX 330, and the mass ratio of the Irganox 1076 antioxidant to the ETHANOX 330 antioxidant is 3:2.

[0125] The grade of the wear-resistant additive is Licowax E powder.

[0126] The second aspect of this example provides a method for preparing polyurethane for a doffing disk, comprising:

[0127] S1. Add long-chain polyol into the reactor, heat the reactor to 105°C, then add antioxidant and wear-resistant additive, stir and disperse, vacuum and degas for 2h at 105°C until all materials in the reactor are completely dissolved, turn off the vacuum and continue stirring for 30min, then reduce the temperature in the reactor to 75°C;

[0128] S2, adding diisocyanate into the reaction kettle and stirring and mixing, when the NCO% content in the system drops to 8.8%, stopping stirring to obtain a polyurethane prepolymer;

[0129] S3. Mix the alcohol chain extender and curing agent, add them to the polyurethane prepolymer, mix and degas in a planetary mixer for 30 seconds, then pour into a mold at 120°C, place the mold in an oven at 110°C and vulcanize for 16 hours to obtain the product.

[0130] Performance Evaluation

[0131] 1. Physical performance test

[0132] Test object: polyurethane for doffer disk prepared in Examples 1-2 and Comparative Examples 1-5.

[0133] The test methods and test results are detailed in Table 1.

[0134] Table 1

[0135]

[0136] 2. Aging resistance test

[0137] Test object: polyurethane for doffer disk prepared in Examples 1-2 and Comparative Examples 1-5.

[0138] Test conditions: Place in an aging test box at 85℃, 85RH% for 500h. After 500h aging, test the strength and strength retention rate.

[0139] The test methods and test results are detailed in Table 2.

[0140] Table 2

[0141]

[0142]

[0143] It can be seen from the combination of Examples 1-2 and Comparative Examples 1-2 that, for the polyurethane provided by the present invention, selecting polyaspartic acid ester as the amine chain extender has better wear resistance and aging resistance than MOCA.

[0144] It can be seen from Examples 1-2 and Comparative Example 3 that, for the polyurethane provided by the present invention, the amine chain extender and the alcohol chain extender are compounded, and the product has better wear resistance and aging resistance compared with the single-component alcohol chain extender.

[0145] It can be seen from Examples 1-2 and Comparative Examples 4-5 that, for the polyurethane provided by the present invention, the amine chain extender and the alcohol chain extender are selected for compounding, and the product has better wear resistance and aging resistance than the compounding of TMP or HDI trimer and the alcohol chain extender.

Claims

1. A polyurethane for a doffer disk, characterized in that: The preparation raw materials include: long-chain polyol, diisocyanate, alcohol chain extender, amine chain extender, antioxidant and wear-resistant additive.

2. The polyurethane for doffer disk according to claim 1, characterized in that: The raw materials for preparing the polyurethane for the cotton doffing disk include, by weight, 50-70 parts of long-chain polyols, 20-40 parts of diisocyanates, 5-10 parts of alcohol chain extenders, 1-5 parts of amine chain extenders, 0.1-1 parts of antioxidants, and 0.1-1 parts of wear-resistant additives.

3. The polyurethane for doffer disk according to claim 1, characterized in that: The long-chain polyols include polyester polyols and / or polyether polyols.

4. The polyurethane for doffer disc according to claim 3, characterized in that: The polyester polyol includes: one of polycarbonate diol, polyethylene adipate diol and polycaprolactone diol.

5. The polyurethane for doffer disk according to claim 3, characterized in that: The polyether polyol includes: polytetramethylene ether glycol and / or polyethylene glycol.

6. The polyurethane for doffer disk according to claim 1, characterized in that: The alcohol chain extender includes one of 1,3-butanediol, 1,4-butanediol, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,5-pentanediol, 1,4-cyclohexanedimethanol and 1,6-hexanediol.

7. The polyurethane for doffer disk according to any one of claims 1 to 6, characterized in that: The amine chain extender includes one of triethylenetetramine, diethylenetriamine, ethylenediamine, diethylenetriamine, 3,3-dichloro-4,4-diaminodiphenylmethanediamine and polyaspartic acid ester.

8. The polyurethane for doffer disk according to claim 1, characterized in that: The brands of the antioxidant include: one or more of Tinuvin PUR 866, SI Group AT 215, SI Group AT 168, Irganox 1010, Irganox 1076, ETHANOX 330, and Hostanox SE 10.

9. The polyurethane for doffer disk according to claim 1, characterized in that: The wear-resistant additive is wax powder, and the brands of the wax powder include: one of Licowax C micro powder PM, Licowax E powder, Licowax C powder, and Licowax PE 520 fine grain.

10. A method for preparing polyurethane for doffer disk according to any one of claims 1 to 9, characterized in that: include: S1. Add long-chain polyols into a reactor, heat the reactor to 100-105°C, then add antioxidants and wear-resistant additives, stir and disperse, vacuum and degas at 100-110°C until all materials in the reactor are completely dissolved, turn off the vacuum and continue stirring, then reduce the temperature in the reactor to 70-80°C; S2, adding diisocyanate into the reaction kettle and stirring and mixing, when the NCO% content in the system drops to 7-9%, stopping stirring to obtain a polyurethane prepolymer; S3. Mix the alcohol chain extender and the amine chain extender, add them to the polyurethane prepolymer, mix and degas in a planetary mixer, pour into a mold, place the mold in an oven at 110-120° C. and vulcanize for 16-24 hours to obtain the product.

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