Polyether-modified hydroxyl-terminated dyed vegetable oil polyol encapsulating material and use thereof

Abstract

The application discloses a polyether modified end hydroxyl dyed vegetable oil polyol coating material and application thereof, and relates to the technical field of fertilizer coating materials, in particular to a polyether modified end hydroxyl dyed vegetable oil polyol coating material and application thereof. The polyether modified end hydroxyl dyed vegetable oil polyol coating material is prepared from a basic film material, polyether polyol and end hydroxyl dye, wherein the basic film material is composed of castor oil based polyol and isocyanate at a mass ratio of (1-2):1; the polyether polyol accounts for 10-15% of the mass of the basic film material; and the end hydroxyl dye accounts for 5-15% of the mass of the basic film material. The castor oil based polyol, isocyanate, polyether polyol and end hydroxyl dye are compounded to prepare the coating material. The castor oil based polyol and the polyether polyol are reacted with the isocyanate to form a soft and hard segment structure of polyurethane. The introduction of the end hydroxyl dye promotes the crosslinking between chains and forms an interpenetrating network structure, thereby improving the mechanical properties and stability of the material. By adjusting the proportion of each component, the flexibility, hardness, wear resistance and functionality of the coating material can be accurately controlled, so that the requirement of high performance of the fertilizer coating is met.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of film-coated controlled-release fertilizer production, and in particular to a polyether-modified hydroxyl-terminated dyed vegetable oil polyol film-coated material and its application. BACKGROUND

[0002] In modern agricultural production, fertilizer application is a key link to improve crop yield and quality. However, in the actual fertilization process, fertilizer particles are often subjected to transportation, friction and impact by mechanical fertilization equipment, which easily leads to particle pulverization, breakage or wear. This phenomenon not only leads to uneven distribution of fertilizer particles, but also can reduce the utilization rate of fertilizer and increase the cost of agricultural production. At the same time, the breakage of fertilizer particles can also cause dust pollution, which has adverse effects on the environment and the health of operators.

[0003] In order to reduce the breakage of particles and dust pollution, current common practice is to protect the fertilizer particles by coating. The coating material can form a protective layer on the surface of the particles, improving the wear resistance and mechanical strength of the particles. However, the existing fertilizer coating materials mainly include polyvinyl alcohol and wax material coating materials, inorganic mineral coatings, pure polyurethane materials and bio-based materials, but they still have many shortcomings in terms of wear resistance: polyvinyl alcohol and wax materials are commonly used for coating of fertilizer particles, but under high-strength friction and impact of mechanical fertilization equipment, they are prone to wear, cracking or peeling, which leads to coating failure, breakage of fertilizer particles and affects the slow-release performance and uniform application of fertilizer; inorganic mineral coatings such as bentonite and talc have low cost, but their wear resistance is poor and they easily fall off during fertilization, failing to provide effective protection; pure polyurethane materials have good mechanical strength and weather resistance, but their adhesion to fertilizer particles is poor, leading to easy peeling of the coating during fertilization and reducing the utilization rate of the fertilizer; bio-based materials mainly include starch-based and cellulose-based materials and aliphatic polyester materials, which have environmental characteristics, but their mechanical strength and wear resistance are low, and the coating is easily broken or worn during mechanical fertilization, failing to effectively protect the fertilizer particles; aliphatic polyester materials such as polylactic acid materials have certain mechanical strength, but their wear resistance still cannot meet the requirements of high-strength fertilization equipment. The above problems seriously affect the use effect of fertilizer particles and limit the improvement of agricultural production efficiency, so it is urgent to develop a new type of coating material with good wear resistance to solve the problems in the prior art. SUMMARY

[0004] In view of the above prior art, the present application aims to provide a polyether-modified hydroxyl-terminated dyed vegetable oil polyol film-coated material and its application.

[0005] To achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0006] In a first aspect, the present application provides a polyether-modified plant oil polyol coating material with end-hydroxyl dyed, which is prepared from a base film material, a polyether polyol and an end-hydroxyl dye, wherein the base film material is composed of castor oil-based polyol and isocyanate in a mass ratio of (1-2):1.

[0007] The polyether polyol accounts for 10-15% of the mass of the base film material, and the end-hydroxyl dye accounts for 5-15% of the mass of the base film material.

[0008] Preferably, the end-hydroxyl dye is 1-amino-4-hydroxy-2-(6-hydroxyhexyloxy) anthraquinone.

[0009] Preferably, the polyether polyol is one or more of polyethylene glycol (PEG), polytetramethylene glycol (PTMEG) and polypropylene glycol (PPG).

[0010] Preferably, the isocyanate is a polyaryl polyisocyanate.

[0011] In a second aspect, the present application provides the use of the polyether-modified plant oil polyol coating material with end-hydroxyl dyed in the preparation of a wear-resistant coated fertilizer.

[0012] In a third aspect, the present application provides a wear-resistant coated fertilizer, which comprises fertilizer particles, an inner coating layer and an outer coating layer, wherein the material of the inner coating layer is polyolefin wax, and the material of the outer coating layer is the polyether-modified plant oil polyol coating material with end-hydroxyl dyed.

[0013] Preferably, the wear-resistant coated fertilizer is prepared by the following method:

[0014] The fertilizer particles are heated to 50-70℃ in a coating machine, and polyolefin wax is sprayed on the surface of the fertilizer particles to form a wax primer layer.

[0015] The polyether-modified plant oil polyol coating material with end-hydroxyl dyed is sprayed in batches onto the wax primer layer, and the input amount of the polyether-modified plant oil polyol coating material with end-hydroxyl dyed in each time is 1-2% of the total mass of the fertilizer particles, and the curing time is 3-6 minutes; the above steps are repeated until the polyether-modified plant oil polyol coating material with end-hydroxyl dyed accounts for 3-4.5% of the total mass of the fertilizer particles.

[0016] Preferably, the addition amount of the polyolefin wax is 4-6‰ of the mass of the fertilizer particles.

[0017] Preferably, the fertilizer particles are one or more of urea, diammonium phosphate, potassium chloride and compound fertilizer.

[0018] Preferably, the particle size of the fertilizer particles is 2-5mm.

[0019] The beneficial effects of the present application are:

[0020] 1、The present application prepares a coating material by compounding castor oil-based polyol, isocyanate, polyether polyol and hydroxyl-terminated dye, castor oil is a natural ternary hydroxyl fatty acid ester, containing rich hydroxyl (-OH) groups, which can be used as a polyol component in polyurethane synthesis, the long-chain fatty acid of castor oil provides flexible segments, giving the material good flexibility and impact resistance, castor oil improves the flexibility of the coating material, enhances the impact resistance and crack resistance, and prevents the coating from being damaged during mechanical fertilization; polyether polyol (such as polyethylene glycol PEG, polytetrahydrofuran PTMEG, polypropylene glycol PPG) contains multiple hydroxyl groups, which can react with isocyanate to form the soft segment of polyurethane, together with castor oil-based polyol, to adjust the elastic modulus and hydrolysis resistance of the coating material, improve the weather resistance and environmental stability of the material; isocyanate (-NCO group) is the core reactant for polyurethane synthesis, which undergoes addition reaction with the hydroxyl groups of polyol to form polyurethane bond (-NH-COO-), providing the hardness and mechanical strength of the coating material, forming a dense polymer network structure, enhancing the wear resistance and chemical resistance of the material; the hydroxyl-terminated dye molecule contains hydroxyl groups, which can participate in the crosslinking reaction of polyurethane, embedded in the polymer chain, and the chromophore structure of the dye molecule can also act as a chain extender or end-capping agent, existing in the side chain, main chain intermediate or terminal position of polyurethane, enhancing the wear resistance and adhesion of the coating material, and giving the material specific functionality (such as color indication, ultraviolet shielding), the covalent bonding prevents the migration of the dye, improving the stability of the material; the reaction of castor oil-based polyol and polyether polyol with isocyanate forms the soft and hard segment structure of polyurethane, the introduction of hydroxyl-terminated dye promotes the crosslinking between chains, forming an interpenetrating network structure, improving the mechanical properties and stability of the material, by adjusting the proportion of each component, the flexibility, hardness, wear resistance and functionality of the coating material can be accurately controlled, meeting the requirements of high performance of fertilizer coating.

[0021] 2、The application sprays a layer of polyolefin wax on the surface of the fertilizer particles to form a wax primer, which has the following main effects: improving the adhesion of the coating material; the polyolefin wax forms a uniform and smooth coating on the surface of the fertilizer particles, fills the micro defects on the surface of the particles, and provides a good base; the wax primer improves the interfacial bonding between the subsequent coating material and the fertilizer particles, preventing the coating from falling off under mechanical action; improving the interface; the polyolefin wax forms a uniform and smooth coating on the surface of the fertilizer particles, fills the micro defects on the surface of the particles, and provides a good base; promoting adhesion; the wax primer improves the interfacial bonding between the subsequent coating material and the fertilizer particles, preventing the coating from falling off under mechanical action; enhancing wear resistance and protection; the polyolefin wax itself has a certain wear resistance, which can provide preliminary protection for the fertilizer particles, reduce direct wear, and together with the subsequent coating material, further improve the overall wear resistance of the coated fertilizer.

[0022] 3、The application uses a one-step method to prepare the target polyurethane, wherein the one-step method refers to a method of adding castor oil-based polyol, isocyanate, polyether polyol and hydroxyl-terminated dye into the reaction system at the initial stage of the reaction for reaction, which has the advantages of simple process and convenient operation. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 : The number of days of nitrogen release of the wear-resistant coated fertilizer prepared in Examples 1-5 before and after wear;

[0024] Figure 2 : The ratio of the number of days of nitrogen release of the wear-resistant coated fertilizer prepared in Examples 1-5 before and after wear;

[0025] Figure 3 : The number of days of nitrogen release of the wear-resistant coated fertilizer prepared in Comparative Examples 1-3 before and after wear. DETAILED DESCRIPTION

[0026] It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs.

[0027] In order for those skilled in the art to more clearly understand the technical solutions of the present application, the technical solutions of the present application will be described in detail below with specific examples.

[0028] The test materials used in the embodiments of the present application are all conventional test materials in the art and can be purchased through commercial channels.

[0029] 1-amino-4-hydroxy-2-(6-hydroxyhexyloxy)anthraquinone (AHHA) used in the present application is purchased from Finer Dye Stuff Chemical Co., Ltd. in Hong Kong, China.

[0030] Polyolefin wax used in the present application is purchased from National Pharmaceutical Group Chemical Reagent Co., Ltd.

[0031] Castor oil-based polyol used in the present application is purchased from Shandong Deken Wisdom Fertilizer Technology Co., Ltd.

[0032] Polyaryl polyisocyanate (PAPI, 31 wt% NCO groups) used in the present application is purchased from Yantai Wanhua Polyurethane Co., Ltd.

[0033] Example 1: Preparation of abrasion-resistant coated fertilizer

[0034] (1) 2-5 mm urea particles (1 kg) were added to a rotating drum and preheated to 60±2°C,

[0035] (2) 5 g of polyolefin wax was used as a surface modifier to uniformly coat the surface of the urea particles, mixed for 10 min to form a wax primer layer;

[0036] (3) Then, castor oil-based polyol and isocyanate were mixed in a mass ratio of 1.3:1 to obtain a base film material, and polyethylene glycol and 1-amino-4-hydroxy-2-(6-hydroxyhexyloxy)anthraquinone (AHHA) were added to the base film material, the addition amount of polyethylene glycol was 10% of the mass of the base film material, and the addition amount of AHHA was 10% of the mass of the base film material, to obtain a polyether-modified hydroxyl-terminated plant oil polyol coating material;

[0037] (4) 1% of the polyether-modified hydroxyl-terminated plant oil polyol coating material based on the weight of the fertilizer core was sprayed onto the preheated urea particles, and cured for 5 minutes; repeated 3 times until the target coating amount, cured to form a polyurethane film layer, to obtain an abrasion-resistant coated fertilizer.

[0038] Example 2: Preparation of abrasion-resistant coated fertilizer

[0039] (1) 2-5 mm urea particles (1 kg) were added to a rotating drum and preheated to 60±2°C,

[0040] (2) 5 g of polyolefin wax was used as a surface modifier to uniformly coat the surface of the urea particles, mixed for 10 min to form a wax primer layer;

[0041] (3) Then the ratio of castor oil based polyol and isocyanate is mixed uniformly according to the mass ratio 1.3:1 to obtain the base film material, polyethylene glycol and 1-amino-4-hydroxy-2-(6-hydroxyhexyloxy) anthraquinone (AHHA) are added to the base film material, the addition amount of polyethylene glycol is 10% of the mass of the base film material, and the addition amount of AHHA is 5% of the mass of the base film material, to obtain a polyether modified end hydroxyl dyed vegetable oil polyol coating material;

[0042] (4) The polyether modified end hydroxyl dyed vegetable oil polyol coating material accounting for 1% of the weight of the fertilizer core is sprayed to the preheated urea particles, and cured for 5 minutes; repeated 3 times until the target coating amount, cured to form a polyurethane film layer, to obtain a wear-resistant coated fertilizer.

[0043] Example 3: Preparation of wear-resistant coated fertilizer:

[0044] (1) 2-5mm urea particles (1kg) are added to the drum and preheated to 60±2℃,

[0045] (2) 5g of polyolefin wax is uniformly coated on the surface of the urea particles as a surface modifier, mixed for 10min to form a wax primer layer;

[0046] (3) Then the ratio of castor oil based polyol and isocyanate is mixed uniformly according to the mass ratio 1.3:1 to obtain the base film material, polyethylene glycol and 1-amino-4-hydroxy-2-(6-hydroxyhexyloxy) anthraquinone (AHHA) are added to the base film material, the addition amount of polyethylene glycol is 10% of the mass of the base film material, and the addition amount of AHHA is 5% of the mass of the base film material, to obtain a polyether modified end hydroxyl dyed vegetable oil polyol coating material;

[0047] (4) The polyether modified end hydroxyl dyed vegetable oil polyol coating material accounting for 1% of the weight of the fertilizer core is sprayed to the preheated urea particles, and cured for 5 minutes; repeated 3 times until the target coating amount, cured to form a polyurethane film layer, to obtain a wear-resistant coated fertilizer.

[0048] Example 4: Preparation of wear-resistant coated fertilizer:

[0049] (1) 2-5mm urea particles (1kg) are added to the drum and preheated to 60±2℃,

[0050] (2) 5g of polyolefin wax is uniformly coated on the surface of the urea particles as a surface modifier, mixed for 10min to form a wax primer layer;

[0051] (3) Then the ratio of castor oil based polyol and isocyanate is mixed uniformly according to the mass ratio 1.3:1 to obtain the base film material, polyethylene glycol and 1-amino-4-hydroxy-2-(6-hydroxyhexyloxy) anthraquinone (AHHA) are added to the base film material, the addition amount of polyethylene glycol is 15% of the mass of the base film material, and the addition amount of AHHA is 10% of the mass of the base film material, to obtain a polyether modified hydroxyl terminated plant oil polyol coated material;

[0052] (4) The polyether modified hydroxyl terminated plant oil polyol coated material accounting for 1% of the weight of the fertilizer core is sprayed to the preheated urea particles, and cured for 5 minutes; repeat 3 times until the target coating amount, and cured to form a polyurethane film layer to obtain a wear-resistant coated fertilizer.

[0053] Example 5: Preparation of wear-resistant coated fertilizer

[0054] (1) 2-5mm urea particles (1kg) are added to a rotating drum and preheated to 60±2℃,

[0055] (2) 5g of polyolefin wax is uniformly coated on the surface of the urea particles as a surface modifier, mixed for 10min to form a wax primer layer;

[0056] (3) Then the ratio of castor oil based polyol and isocyanate is mixed uniformly according to the mass ratio 1.3:1 to obtain the base film material, polyethylene glycol and 1-amino-4-hydroxy-2-(6-hydroxyhexyloxy) anthraquinone (AHHA) are added to the base film material, the addition amount of polyethylene glycol is 15% of the mass of the base film material, and the addition amount of AHHA is 10% of the mass of the base film material, to obtain a polyether modified hydroxyl terminated plant oil polyol coated material;

[0057] (4) The polyether modified hydroxyl terminated plant oil polyol coated material accounting for 1% of the weight of the fertilizer core is sprayed to the preheated urea particles, and cured for 5 minutes; repeat 3 times until the target coating amount, and cured to form a polyurethane film layer to obtain a wear-resistant coated fertilizer.

[0058] Comparative Example 1

[0059] (1) 2-5mm urea particles (1kg) are added to a rotating drum and preheated to 60±2℃,

[0060] (2) 5g of polyolefin wax is uniformly coated on the surface of the urea particles as a surface modifier, mixed for 10min to form a wax primer layer;

[0061] (3) Then the ratio of castor oil based polyol and isocyanate is mixed uniformly according to the mass ratio 1.3:1 to obtain the base film material, polyethylene glycol and 1-amino-4-hydroxy-2-(6-hydroxyhexyloxy) anthraquinone (AHHA) are added to the base film material, the addition amount of polyethylene glycol is 15% of the mass of the base film material, and the addition amount of AHHA is 10% of the mass of the base film material, to obtain a polyether modified hydroxyl terminated plant oil polyol coated material;

[0062] (4) Take 1% of the core weight of the fertilizer coated with the coating material on the preheated urea particles, and solidify for 5 minutes; repeat 3 times until the target coating amount, solidify the film, form a polyurethane film layer, and obtain a 3% coated fertilizer.

[0063] Comparative Example 2:

[0064] (1) Add 2-5 mm urea particles (1 kg) to the rotating drum, preheat to 60±2℃,

[0065] (2) 5g polyolefin wax as a surface modifier is uniformly coated on the surface of the urea particles, mixed for 10 min, and a wax primer layer is formed;

[0066] (3) Then mix the castor oil-based polyol and isocyanate in a mass ratio of 1.3:1 to form a coating material;

[0067] (4) Take 1% of the core weight of the fertilizer coated with the coating material on the preheated urea particles, and solidify for 5 minutes; repeat 3 times until the target coating amount, solidify the film, form a polyurethane film layer, and obtain a 3% coated fertilizer.

[0068] Comparative Example 3:

[0069] (1) Add 2-5 mm urea particles (1 kg) to the rotating drum, preheat to 60±2℃,

[0070] (2) 5g polyolefin wax as a surface modifier is uniformly coated on the surface of the urea particles, mixed for 10 min, and a wax primer layer is formed;

[0071] (3) Then mix the castor oil-based polyol and isocyanate in a mass ratio of 1.3:1 to form a coating material;

[0072] (4) Take 1% of the core weight of the fertilizer coated with the coating material on the preheated urea particles, and solidify for 5 minutes; repeat 3 times until the target coating amount, solidify the film, form a polyurethane film layer, and obtain a 3% coated fertilizer.

[0073] Test Example:

[0074] 1. Test method:

[0075] 1.1 Controlled-release fertilizer release rate detection:

[0076] According to international standard ISO 18644-2016, the nitrogen release rate of the coated fertilizer prepared in Examples 1-5 and Comparative Examples 1-3 before abrasion is determined:

[0077] Weigh 10.00g of the coated controlled-release fertilizer sample and place it in a glass container containing 200.0mL of distilled water. After sealing, place it in a constant temperature incubator at 25℃. On days 1, 3, 5, 7, 14, 28, 42, 56, and 70, remove the leachate from the container and determine its nitrogen content. Add 200.0mL of distilled water again and continue soaking and measuring until the fertilizer nitrogen release rate reaches 80%.

[0078] 1.2 Controlled-release fertilizer wear treatment: Weigh 50g of different coated fertilizers and put them into a drum with a rotation speed of 3r / min. Use 60-grit sandpaper to polish them for 3min. Take out the worn fertilizers and then test the controlled-release fertilizer release rate again according to the method in step 1. Determine the nitrogen release rate of the coated fertilizers prepared in Examples 1-5 and Comparative Examples 1-3 after wear.

[0079] 2. Experimental Results:

[0080] Depend on Figure 1 It can be seen that the coated fertilizer prepared in Example 1 was prepared by adding 10% polyethylene glycol and 10% AHHA to the base membrane material (castor oil-based polyol and isocyanate). The cumulative release days in 25°C static water reached a maximum of 91 days, and the release days after wear was the highest at 83 days. The ratio of release days after wear to release days before wear was 0.912, which was closest to 1, indicating that the fertilizer release was least affected by wear and the membrane material had the highest wear resistance. The ratio of release days after wear to release days before wear of the coated fertilizers prepared in Examples 2-5 was also greater than 0.88, indicating that the wear-resistant film material prepared by the method of the present invention can effectively improve the wear resistance of fertilizer.

[0081] Comparative Example 1, which added 10% polyethylene glycol to the base membrane material, had a release day ratio of 0.506 after wear to before wear; Comparative Example 2, which added 10% AHHA to the base membrane material, had a release day ratio of 0.351 after wear; and Comparative Example 3, which used the base membrane material for coating to prepare coated fertilizer, had a release day ratio of 0.156 after wear. These results indicate that the addition of polyethylene glycol and the hydroxyl-terminated dye AHHA has a synergistic effect in improving the wear resistance of the membrane material.

[0082] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A polyether-modified, hydroxyl-terminated, dyed, plant oil polyol encapsulating material, characterized in that, The polyether modified end-hydroxyl dyed vegetable oil polyol coating material is prepared from a base film material, a polyether polyol and an end-hydroxyl dye, wherein the base film material is composed of castor oil based polyol and isocyanate in a mass ratio of (1-2):1; The polyether polyol accounts for 10-15% of the mass of the base film material, and the end-hydroxyl dye accounts for 5-15% of the mass of the base film material. The end-hydroxyl dye is 1-amino-4-hydroxy-2-(6-hydroxyhexyloxy) anthraquinone. The polyether polyol is one or more of polyethylene glycol and polypropylene glycol. The isocyanate is polyaryl polyisocyanate.

2. Use of the polyether modified end-hydroxyl dyed vegetable oil polyol coating material of claim 1 in the preparation of a wear-resistant coated fertilizer.

3. A wear resistant coated fertilizer, characterized by, The wear-resistant coated fertilizer comprises fertilizer particles, an inner coating layer and an outer coating layer, the material of the inner coating layer is polyolefin wax, and the material of the outer coating layer is the polyether modified end-hydroxyl dyed vegetable oil polyol coating material of claim 1.

4. The wear-resistant coated fertilizer of claim 3, wherein, The wear-resistant coated fertilizer is prepared by the following method: The fertilizer particles are heated to 50-70℃ in a coating machine, and polyolefin wax is sprayed on the surface of the fertilizer particles to form a wax primer layer; The polyether modified end-hydroxyl dyed vegetable oil polyol coating material of claim 1 is sprayed in batches on the wax primer layer, and the input amount of the polyether modified end-hydroxyl dyed vegetable oil polyol coating material each time is 1-2% of the total mass of the fertilizer particles, and the curing time is 3-6 minutes; the above steps are repeated until the polyether modified end-hydroxyl dyed vegetable oil polyol coating material accounts for 3-4.5% of the total mass of the fertilizer particles.

5. The wear-resistant coated fertilizer of claim 3, wherein, The addition amount of the polyolefin wax is 4-6‰ of the mass of the fertilizer particles.

6. The wear-resistant coated fertilizer of claim 3, wherein, The fertilizer particles are one or more of urea, potassium chloride and compound fertilizer, and the particle size of the fertilizer particles is 2-5 mm. The polyether modified end-hydroxyl dyed vegetable oil polyol coating material is prepared from a base film material, a polyether polyol and an end-hydroxyl dye, wherein the base film material is composed of castor oil based polyol and isocyanate in a mass ratio of (1-2):1; The polyether polyol accounts for 10-15% of the mass of the base film material, and the end-hydroxyl dye accounts for 5-15% of the mass of the base film material. The end-hydroxyl dye is 1-amino-4-hydroxy-2-(6-hydroxyhexyloxy) anthraquinone. The polyether polyol is one or more of polyethylene glycol and polypropylene glycol. The isocyanate is polyaryl polyisocyanate.

2. Use of the polyether modified end-hydroxyl dyed vegetable oil polyol coating material of claim 1 in the preparation of a wear-resistant coated fertilizer. The wear-resistant coated fertilizer comprises fertilizer particles, an inner coating layer and an outer coating layer, the material of the inner coating layer is polyolefin wax, and the material of the outer coating layer is the polyether modified end-hydroxyl dyed vegetable oil polyol coating material of claim 1. The wear-resistant coated fertilizer is prepared by the following method: The fertilizer particles are heated to 50-70℃ in a coating machine, and polyolefin wax is sprayed on the surface of the fertilizer particles to form a wax primer layer; The polyether modified end-hydroxyl dyed vegetable oil polyol coating material of claim 1 is sprayed in batches on the wax primer layer, and the input amount of the polyether modified end-hydroxyl dyed vegetable oil polyol coating material each time is 1-2% of the total mass of the fertilizer particles, and the curing time is 3-6 minutes; the above steps are repeated until the polyether modified end-hydroxyl dyed vegetable oil polyol coating material accounts for 3-4.5% of the total mass of the fertilizer particles. The addition amount of the polyolefin wax is 4-6‰ of the mass of the fertilizer particles. The fertilizer particles are one or more of urea, potassium chloride and compound fertilizer, and the particle size of the fertilizer particles is 2-5 mm.

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