CN112209772A - Preparation method of oil-based polyurethane slow-release nitrogen fertilizer - Google Patents
Preparation method of oil-based polyurethane slow-release nitrogen fertilizer Download PDFInfo
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- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
- C05G3/00—Mixtures of one or more fertilisers with additives not having a specially fertilising activity
- C05G3/40—Mixtures of one or more fertilisers with additives not having a specially fertilising activity for affecting fertiliser dosage or release rate; for affecting solubility
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- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05C—NITROGENOUS FERTILISERS
- C05C9/00—Fertilisers containing urea or urea compounds
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- C05—FERTILISERS; MANUFACTURE THEREOF
- C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
- C05G5/00—Fertilisers characterised by their form
- C05G5/30—Layered or coated, e.g. dust-preventing coatings
- C05G5/37—Layered or coated, e.g. dust-preventing coatings layered or coated with a polymer
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- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G71/00—Macromolecular compounds obtained by reactions forming a ureide or urethane link, otherwise, than from isocyanate radicals in the main chain of the macromolecule
- C08G71/04—Polyurethanes
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Abstract
The invention discloses a preparation method of an oil-based polyurethane slow-release nitrogen fertilizer, belonging to the technical field of non-isocyanate polyurethane slow-release fertilizers. The preparation process mainly comprises the following steps: carrying out alcoholysis reaction, namely taking a certain amount of urea particles and castor oil, carrying out alcoholysis reaction under the action of a catalyst, forming uniformly distributed cyclic carbonate intermediate products on the surfaces of the urea particles in the process, separating solid particles after the reaction is finished, adding polyamine, carrying out polymerization reaction, removing redundant reactants after the reaction, and finally drying to obtain the polyurethane coated slow-release nitrogen fertilizer. The invention takes urea particles as reactants, and the urea particles are directly subjected to alcoholysis polymerization to form a film on the surfaces of the urea particles, and has the advantages of low raw material cost, easy operation of the preparation method, controllable nitrogen fertilizer slow-release time and the like.
Description
Technical Field
The invention belongs to the technical field of non-isocyanate polyurethane slow-release fertilizers, and particularly relates to a preparation method of an oil-based polyurethane slow-release nitrogen fertilizer.
Background
China is a big agricultural country, and chemical fertilizers play an important role in agricultural production. However, the utilization rate of available nutrients of chemical fertilizers is not high in China, the waste amount of the chemical fertilizers is large, and the actual absorption amount of crops is very small, so that not only is the soil and water seriously polluted, but also huge waste of energy and financial resources is caused.
The advent of coated fertilizers has effectively alleviated this problem. The coated fertilizer is a slow/controlled release fertilizer which develops rapidly in recent years, takes water-soluble fertilizer granules as cores, and the coating material made of inorganic matters or organic polymers with low water solubility or slightly solubility is coated on the surfaces of the fertilizer granules, so that the nutrient release rate is adjusted and controlled according to the fertilizer demand of crops in different growth periods, the high yield can be kept on the premise of reducing pollution as much as possible, and the coated fertilizer becomes an agricultural green fertilizer.
At present, the coated slow release fertilizer coated by organic high molecular materials is the main research direction of the coated fertilizer. A large number of researches show that the application of the organic high-molecular polymer coated slow-release fertilizer can obviously improve the utilization efficiency of the fertilizer and reduce the nutrient loss and the pollution to the environment. However, the film-coated slow-release fertilizer coated by the high polymer material also has some problems, such as the nutrient controlled-release time still cannot be well matched with the fertilizer-requiring time of crops; after nutrients are released, the organic polymer shells remained in the soil are difficult to degrade; most film forming materials are organic solvents, so that the toxicity is high, the environmental pollution is caused, and the like. Therefore, the development of a novel, aqueous, efficient and degradable organic high polymer membrane material has become a hotspot in the research field of coated slow-release fertilizers.
Polyurethane is one of synthetic resins having excellent comprehensive properties. Because of the variety of synthetic monomers, mild reaction conditions, specificity, controllability, large formula adjustment margin and the microstructure characteristics of high molecular materials, the material can be widely used for coatings, adhesives, foamed plastics, synthetic fibers and elastomers, and becomes one of the essential materials in the fields of clothing, food, live, operation and high and new technology.
Currently, most polyurethanes are formed from di (or poly) isocyanates, di (or poly) polyols and di (or poly) amines by a step-wise polymerization reaction. But the raw material isocyanate has high toxicity and strong volatility, and has great harm to environmental protection and human safety in the using process. Secondly, isocyanates are extremely sensitive to environmental conditions and are prone to inducing side reactions with moisture in high humidity to produce CO2Go forward and go forwardAffecting its performance. In recent years, the superior properties and wide use of non-isocyanate polyurethanes (NIPU) have been increasingly developed and studied.
In Chinese patent CN 108864393A, a preparation method of modified bio-based polyurethane and application thereof in slow release fertilizer are disclosed, the invention purifies recycled edible oil, repeatedly used frying oil and the like, synthesizes novel bio-based polyurethane, uses KH550 to modify PUs, and uses the modified PUs as a coating material to coat urea to prepare degradable coated slow release fertilizer (PCUs). However, the modification process of the invention is complex, and the release period of the slow release fertilizer is not long.
Chinese patent CN 104108991A discloses a polyurethane coated slow-release compound fertilizer containing catechol, which is prepared from the following raw materials in parts by weight: 10-15 parts of 1250-2000-mesh diatomite, 6-9 parts of bean curd wastewater, 12-15 parts of phosphorus pentoxide, 6-8 parts of sodium polyaspartate, 20-22 parts of decomposed gallery fertilizer, 10-12 parts of decomposed traditional Chinese medicine residues, 15-18 parts of ammonium bicarbonate, 2-4 parts of ferrous sulfate, 12-15 parts of phosphogypsum, 2-3 parts of methionine, 16-18 parts of rice chaff, 2-4 parts of catechol, 1-3 parts of acetylcholine, 0.1-0.2 part of sodium nitrophenolate, 20-25 parts of palm oil modified aqueous polyurethane emulsion, 3-5 parts of colloidal lithium magnesium silicate and 4-5 parts of an auxiliary agent. Although the film layer coated and formed by the method is not easy to damage, the method has the problems of poor particle uniformity, high cost, high energy consumption, uneven nutrient release and the like.
In summary, the coating raw materials and processes of the non-isocyanate polyurethane slow-release urea reported in the current patent are complex, and certain problems still exist in the uniformity and controllability of the coating, so that the slow-release effect of the fertilizer is not ideal, and the large-scale application of the fertilizer in industry is restricted.
Disclosure of Invention
The invention aims to solve the technical problem of providing a preparation method of an oil-based polyurethane slow-release nitrogen fertilizer, wherein urea particles are used as reactants and are subjected to alcoholysis polymerization to form a film on the surfaces of the urea particles, and the method is low in harm, low in cost and simple to operate.
In order to achieve the purpose, the invention provides the following technical scheme:
a preparation method of an oil-based polyurethane slow-release nitrogen fertilizer comprises the following steps:
(1) alcoholysis reaction: taking 25-70 parts of urea particles, 0.5-5 parts of catalyst and 15-70 parts of castor oil, placing the urea particles, the catalyst and the castor oil in a reaction container, heating a reaction system in a nitrogen environment, wherein the heating temperature is 40-130 ℃, and reacting for 1-11 hours; after the reaction is finished, separating solid particles by using a filter screen;
(2) polymerization reaction: taking 5-40 parts of polyamine, adding the polyamine into the product obtained in the step (1), standing and reacting for 0.1-4 h at the temperature of 25-100 ℃, and separating solid particles by using a filter screen;
the polyamine is at least one of ethylenediamine, 1, 6-hexamethylenediamine, triethylamine, tri (2-aminoethyl) amine, polyoxypropylene diamine, polyoxypropylene triamine, triethylene tetramine and hexamethylene diamine (1, 6-hexamethylenediamine).
(3) Coating and drying: and (3) naturally drying the product obtained in the step (2) for 6-36 h, and then putting the product into a drying oven for drying to obtain the oil-based polyurethane slow-release nitrogen fertilizer.
Preferably, in the step (1), the diameter of the urea particles is 2-3 mm.
In the step (1), the catalyst is at least one of zinc oxide, magnesium oxide, aluminum oxide, calcium oxide, lanthanum oxide, zirconium oxide, magnesium chloride, zinc chloride, magnesium acetate, zinc-iron composite oxide, zinc-chromium composite oxide, zinc-magnesium composite oxide, zinc-aluminum composite oxide and magnesium-aluminum composite oxide.
In the step (1), the preparation method of the catalyst is a urea precipitation method.
The preparation method of the catalyst zinc oxide further comprises the following steps: zinc oxide reagent drying method, basic zinc carbonate decomposition method, zinc nitrate decomposition method, and zinc oxalate decomposition method.
In the step (1), the nitrogen flow is 25-200 mL/min.
In the step (3), the drying temperature is 25-100 ℃.
In the step (3), the drying time is 0.1-48 h.
The invention has the beneficial effects that:
1. the slow release fertilizer of the invention only needs one-time fertilization, prolongs the nutrient release period of the nitrogen fertilizer, avoids the agricultural cost increased by multiple fertilization, and improves the utilization rate of the nitrogen fertilizer.
2. The oil-based polyurethane film prepared by the invention is degradable, can not generate secondary pollution due to the undegradability of the polyurethane film, has wide sources of used materials and low cost, and lowers the threshold for the popularization of the slow release fertilizer.
3. Urea particles are directly used as raw materials, a cyclic carbonate intermediate is formed on the surface of the urea particles, and polyamine is added for polymerization, so that a good solution is provided for the difficult problems of uneven and incomplete coating.
4. The thickness of the polyurethane film can be controlled by controlling the reaction conditions, and the slow release time is further controlled.
5. The preparation process not only avoids the isocyanate with high toxicity and humidity sensitivity used in the past, but also improves the chemical stability of the product.
Drawings
FIG. 1 is a graph of the nitrogen release profile of examples 1-5;
FIG. 2 is a graph of the nitrogen release profile of examples 6-8;
FIG. 3 is a graph showing the nitrogen release curves of examples 9 to 11;
FIG. 4 is a graph showing the nitrogen release curves of examples 12 to 15 and comparative example.
Detailed Description
The present invention is further illustrated by the following specific examples, which are only a part of the examples of the present invention, and the scope of the present invention is not limited to the examples.
Example 1
Weighing 25 parts of large-particle urea, 1.5 parts of ZnO (urea precipitation method) catalyst and 25 parts of castor oil in a flask, heating to the reaction temperature of 70 ℃, and introducing inert gas N2The reaction was carried out for 5 hours with no stirring, with the flow rate controlled at 100 mL/min. Then, the grafted urea is collected and placed in a beaker, 12.5 parts of ethylenediamine is added, polymerization reaction is carried out at room temperature (25 ℃) for 2 hours, the coated urea is taken out and naturally dried overnight, and finally the coated urea is dried at 40 ℃ for 2 hoursAnd 4h, obtaining the polyurethane coated urea slow-release fertilizer.
Testing the slow release performance: the content of urea in the aqueous solution of the polyurethane slow-release nitrogen fertilizer is detected by utilizing a p-dimethylaminobenzaldehyde chromogenic spectrophotometry, and the slow-release performance of the fertilizer is further known. The method comprises the following steps: 5.00g of polyurethane coated urea is put into a big beaker filled with 1000mL of tap water with the temperature of 25 ℃, 1.5mL of samples are respectively taken at 1 st, 3 rd, 5 th, 7 th, 10 th, 15 th, 25 th, 40 th, 60 th and 90 th min, and after sampling is finished each time, tap water with the same volume is added to ensure the solvent with the same volume. Adding 0.1mL of sample into a 10mL centrifuge tube, adding 1mL of p-dimethylaminobenzaldehyde (PDAB) color developing agent and 0.2mL of 2mol/L sulfuric acid solution, adding 3.7mL of deionized water, mixing, shaking uniformly, and measuring the absorbance of the mixture by using a spectrophotometer by taking a blank reagent as a reference. The preparation method of the blank reagent comprises the following steps: adding 2mL of deionized water into a 10mL centrifuge tube, adding 1mL of PDAB color developing agent, 0.2mL of 2mol/L sulfuric acid solution and then adding 1.8mL of deionized water, mixing and shaking uniformly, measuring absorbance, testing each sample for four times, and taking an average value. Finding out the corresponding concentration through a standard curve, and establishing a slow release curve by taking the time as an abscissa and the release rate of N as an ordinate.
Example 2
Weighing 25 parts of large-particle urea, 1.5 parts of ZnO (roasted zinc nitrate) catalyst and 25 parts of castor oil in a flask, heating to the reaction temperature of 70 ℃, and introducing inert gas N2The reaction was carried out for 5 hours with no stirring, with the flow rate controlled at 100 mL/min. And then, collecting grafted urea, placing the grafted urea in a beaker, adding 12.5 parts of ethylenediamine, carrying out polymerization reaction at room temperature for 2 hours, taking out coated urea, naturally air-drying overnight, and finally drying at 40 ℃ for 24 hours to obtain the polyurethane coated urea slow-release fertilizer.
Performance test methods as in example 1
Example 3
Weighing 25 parts of large-particle urea, 1.5 parts of ZnO (roasted zinc oxalate) catalyst and 25 parts of castor oil in a flask, heating to the reaction temperature of 70 ℃, and introducing inert gas N2The reaction was carried out for 5 hours with no stirring, with the flow rate controlled at 100 mL/min. Subsequently, the grafted urea was collected, placed in a beaker, and 12.5 parts of ethyl were addedAnd (3) carrying out polymerization reaction at room temperature for 2h, taking out the coated urea, naturally air-drying overnight, and finally drying at 40 ℃ for 24h to obtain the polyurethane coated urea slow-release fertilizer.
Performance test methods as in example 1
Example 4
Weighing 25 parts of large-particle urea, drying ZnO reagent, taking 1.5 parts of catalyst and 25 parts of castor oil in a flask, heating to the reaction temperature of 70 ℃, and introducing inert gas N2The reaction was carried out for 5 hours with no stirring, with the flow rate controlled at 100 mL/min. And then, collecting grafted urea, placing the grafted urea in a beaker, adding 12.5 parts of ethylenediamine, carrying out polymerization reaction at room temperature for 2 hours, taking out coated urea, naturally air-drying overnight, and finally drying at 40 ℃ for 24 hours to obtain the polyurethane coated urea slow-release fertilizer.
Performance test methods as in example 1
Example 5
Weighing 25 parts of large granular urea and 25 parts of castor oil in a flask, heating to the reaction temperature of 70 ℃, and introducing inert gas N2The reaction was carried out for 5 hours with no stirring, with the flow rate controlled at 100 mL/min. And then, collecting grafted urea, placing the grafted urea in a beaker, adding 12.5 parts of ethylenediamine, carrying out polymerization reaction at room temperature for 2 hours, taking out coated urea, naturally air-drying overnight, and finally drying at 40 ℃ for 24 hours to obtain the polyurethane coated urea slow-release fertilizer.
Performance test methods as in example 1
Examples 1-5 Nitrogen sustained Release profiles are shown in FIG. 1
Example 6
Weighing 25 parts of large-particle urea, 1.5 parts of Al/Mg composite oxide (urea precipitation method) catalyst and 25 parts of castor oil in a flask, heating to the reaction temperature of 70 ℃, and introducing inert gas N2The reaction was carried out for 5 hours with no stirring, with the flow rate controlled at 100 mL/min. And then, collecting grafted urea, placing the grafted urea in a beaker, adding 12.5 parts of ethylenediamine, carrying out polymerization reaction at room temperature for 2 hours, taking out coated urea, naturally air-drying overnight, and finally drying at 40 ℃ for 24 hours to obtain the polyurethane coated urea slow-release fertilizer.
Performance test methods as in example 1
Example 7
Weighing 25 parts of large-particle urea, 1.5 parts of Zn/Al composite oxide (urea precipitation method) catalyst and 25 parts of castor oil in a flask, heating to the reaction temperature of 70 ℃, and introducing inert gas N2The reaction was carried out for 5 hours with no stirring, with the flow rate controlled at 100 mL/min. And then, collecting grafted urea, placing the grafted urea in a beaker, adding 12.5 parts of ethylenediamine, carrying out polymerization reaction at room temperature for 2 hours, taking out coated urea, naturally air-drying overnight, and finally drying at 40 ℃ for 24 hours to obtain the polyurethane coated urea slow-release fertilizer.
Performance test methods as in example 1
Example 8
Weighing 25 parts of large-particle urea, 1.5 parts of Zn/Mg composite oxide (urea precipitation method) catalyst and 25 parts of castor oil in a flask, heating to the reaction temperature of 70 ℃, and introducing inert gas N2The reaction was carried out for 5 hours with no stirring, with the flow rate controlled at 100 mL/min. And then, collecting grafted urea, placing the grafted urea in a beaker, adding 12.5 parts of ethylenediamine, carrying out polymerization reaction at room temperature for 2 hours, taking out coated urea, naturally air-drying overnight, and finally drying at 40 ℃ for 24 hours to obtain the polyurethane coated urea slow-release fertilizer.
Performance test methods as in example 1
Examples 6-8 Nitrogen release curves are shown in FIG. 2
Example 9
Weighing 25 parts of large-particle urea, 1.5 parts of ZnO (urea precipitation method) catalyst and 25 parts of castor oil in a flask, heating to the reaction temperature of 70 ℃, and introducing inert gas N2The reaction was carried out for 5 hours with no stirring, with the flow rate controlled at 100 mL/min. And then, collecting grafted urea, and finally drying at 40 ℃ for 24h to obtain the polyurethane coated urea slow-release fertilizer.
Performance test methods as in example 1
Example 10
Weighing 25 parts of large-particle urea, 1.5 parts of ZnO catalyst (urea precipitation method) and 25 parts of castor oil in a flask, and heating to the reaction stateThe temperature is 70 ℃, and inert gas N is introduced2The reaction was carried out for 5 hours with no stirring, with the flow rate controlled at 100 mL/min. And then, collecting grafted urea, placing the grafted urea in a beaker, adding 7.5 parts of ethylenediamine, carrying out polymerization reaction at room temperature, contacting for a few seconds, immediately taking out the coated urea, naturally air-drying overnight, and finally drying for 24 hours at 40 ℃ to obtain the polyurethane coated urea slow-release fertilizer.
Performance test methods as in example 1
Example 11
Weighing 25 parts of large-particle urea, 1.5 parts of ZnO (urea precipitation method) catalyst and 25 parts of castor oil in a flask, heating to the reaction temperature of 70 ℃, and introducing inert gas N2The reaction was carried out for 5 hours with no stirring, with the flow rate controlled at 100 mL/min. And then, collecting grafted urea, placing the grafted urea in a beaker, adding 15 parts of ethylenediamine, carrying out polymerization reaction at 70 ℃ for 2 hours, taking out coated urea, naturally air-drying overnight, and finally drying at 40 ℃ for 24 hours to obtain the polyurethane coated urea slow-release fertilizer.
Performance test methods as in example 1
Examples 9-11 Nitrogen sustained Release profiles are shown in FIG. 3
Example 12
Weighing 25 parts of large-particle urea, 1.5 parts of ZnO (urea precipitation method) catalyst and 35 parts of castor oil in a flask, heating to the reaction temperature of 70 ℃, and introducing inert gas N2The reaction was carried out for 5 hours with no stirring, with the flow rate controlled at 100 mL/min. And then, collecting grafted urea, placing the grafted urea in a beaker, adding 12.5 parts of ethylenediamine, carrying out polymerization reaction at room temperature for 2 hours, taking out coated urea, naturally air-drying overnight, and finally drying at 40 ℃ for 24 hours to obtain the polyurethane coated urea slow-release fertilizer.
Performance test methods as in example 1
Example 13
Weighing 25 parts of large-particle urea, 1.5 parts of ZnO (urea precipitation method) catalyst and 25 parts of castor oil in a flask, heating to the reaction temperature of 110 ℃, and introducing inert gas N2The reaction was carried out for 5 hours with no stirring, with the flow rate controlled at 100 mL/min. Then, the grafted urea is collected,and (3) placing the coated urea in a beaker, adding 12.5 parts of ethylenediamine, carrying out polymerization reaction at room temperature for 2 hours, taking out the coated urea, naturally drying the coated urea overnight, and finally drying the coated urea at 40 ℃ for 24 hours to obtain the polyurethane coated urea slow-release fertilizer.
Performance test methods as in example 1
Example 14
Weighing 25 parts of large-particle urea, 1.5 parts of ZnO (urea precipitation method) catalyst and 25 parts of castor oil in a flask, heating to the reaction temperature of 70 ℃, and introducing inert gas N2The reaction was carried out for 9 hours with no stirring, with the flow rate controlled at 100 mL/min. And then, collecting grafted urea, placing the grafted urea in a beaker, adding 12.5 parts of ethylenediamine, carrying out polymerization reaction at room temperature for 2 hours, taking out coated urea, naturally air-drying overnight, and finally drying at 40 ℃ for 24 hours to obtain the polyurethane coated urea slow-release fertilizer.
Performance test methods as in example 1
Example 15
Weighing 25 parts of large-particle urea, 1.5 parts of ZnO (urea precipitation method) catalyst and 25 parts of castor oil in a flask, heating to the reaction temperature of 70 ℃, and introducing inert gas N2The reaction was carried out for 5 hours with no stirring, with the flow rate controlled at 100 mL/min. And then, collecting grafted urea, placing the grafted urea in a beaker, adding 7.5 parts of ethylenediamine, carrying out polymerization reaction at room temperature for 3 hours, taking out coated urea, naturally air-drying overnight, and finally drying at 40 ℃ for 24 hours to obtain the polyurethane coated urea slow-release fertilizer.
Performance test methods as in example 1
Comparative example
Weighing 25 parts of large-particle urea, 1.5 parts of ZnO (urea precipitation method) catalyst and 30 parts of 1, 2-propylene glycol into a flask, heating to the reaction temperature of 70 ℃, and introducing inert gas N2The reaction was carried out for 5 hours with no stirring, with the flow rate controlled at 100 mL/min. And then, collecting grafted urea, placing the grafted urea in a beaker, adding 12.5 parts of ethylenediamine, carrying out polymerization reaction at room temperature for 2 hours, taking out coated urea, naturally air-drying overnight, and finally drying at 40 ℃ for 24 hours to obtain the polyurethane coated urea slow-release fertilizer.
Performance test methods as in example 1
The nitrogen release curves of examples 12 to 15 and comparative examples are shown in FIG. 4
It should be understood that the above embodiments are only preferred embodiments of the present invention, and are not intended to limit the embodiments of the present invention. It will be appreciated by those skilled in the art that changes may be made to the embodiments described above without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims.
Claims (8)
1. A preparation method of an oil-based polyurethane slow-release nitrogen fertilizer is characterized by comprising the following steps:
(1) alcoholysis reaction: taking 25-70 parts of urea particles, 0.5-5 parts of catalyst and 15-70 parts of castor oil, placing the urea particles, the catalyst and the castor oil in a reaction container, heating a reaction system in a nitrogen environment, wherein the heating temperature is 40-130 ℃, and reacting for 1-11 hours; after the reaction is finished, separating solid particles by using a filter screen;
(2) polymerization reaction: taking 5-40 parts of polyamine, adding the polyamine into the product obtained in the step (1), standing and reacting for 0.1-4 h at the temperature of 25-100 ℃, and separating solid particles by using a filter screen;
the polyamine is at least one of ethylenediamine, 1, 6-hexamethylenediamine, triethylamine, tri (2-aminoethyl) amine, polyoxypropylene diamine, polyoxypropylene triamine, triethylene tetramine and hexamethylenediamine (1, 6-hexamethylenediamine);
(3) coating and drying: and (3) naturally drying the product obtained in the step (2) for 6-36 h, and then putting the product into a drying oven for drying to obtain the oil-based polyurethane slow-release nitrogen fertilizer.
2. The method for preparing the oil-based polyurethane slow-release nitrogen fertilizer according to claim 1, wherein in the step (1), the diameter of the urea particles is 2-3 mm.
3. The method for preparing the oil-based polyurethane slow-release nitrogen fertilizer according to claim 1, wherein in the step (1), the catalyst is at least one of zinc oxide, magnesium oxide, aluminum oxide, calcium oxide, lanthanum oxide, zirconium oxide, magnesium chloride, zinc chloride, magnesium acetate, zinc-iron composite oxide, zinc-chromium composite oxide, zinc-magnesium composite oxide, zinc-aluminum composite oxide and magnesium-aluminum composite oxide.
4. The method for preparing the oil-based polyurethane slow-release nitrogen fertilizer as claimed in claim 3, wherein the preparation method of the catalyst is urea precipitation.
5. The method for preparing the oil-based polyurethane slow-release nitrogen fertilizer according to claim 4, wherein the method for preparing the catalyst zinc oxide further comprises the following steps: zinc oxide reagent drying method, basic zinc carbonate decomposition method, zinc nitrate decomposition method and zinc oxalate decomposition method.
6. The preparation method of the oil-based polyurethane slow-release nitrogen fertilizer according to claim 1, wherein in the step (1), the nitrogen flow rate is 25-200 mL/min.
7. The preparation method of the oil-based polyurethane slow-release nitrogen fertilizer according to claim 1, wherein in the step (3), the drying temperature is 25-100 ℃.
8. The preparation method of the oil-based polyurethane slow-release nitrogen fertilizer as claimed in claim 1 or 7, wherein in the step (3), the drying time is 0.1-48 h.
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Cited By (2)
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| CN113582771A (en) * | 2021-08-24 | 2021-11-02 | 温州医科大学 | Preparation method of slow-release fertilizer based on high polymer |
| CN115322367A (en) * | 2022-08-23 | 2022-11-11 | 华南理工大学 | Polyurethane prepared based on urea and preparation method and application thereof |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1880360A (en) * | 2006-05-12 | 2006-12-20 | 中国科学院山西煤炭化学研究所 | Method for generating nonisocyanate polyurethane using natural reproducible resource |
| CN104725633A (en) * | 2014-12-10 | 2015-06-24 | 陆喜 | Preparation method of all-bio-based elastomer |
| CN109206155A (en) * | 2018-10-25 | 2019-01-15 | 吉林师范大学 | A method of preparing slow-release carbamide |
| CN109467664A (en) * | 2017-09-08 | 2019-03-15 | 汪上晓 | The preparation method of polyurethane resin |
-
2020
- 2020-11-09 CN CN202011235393.6A patent/CN112209772A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1880360A (en) * | 2006-05-12 | 2006-12-20 | 中国科学院山西煤炭化学研究所 | Method for generating nonisocyanate polyurethane using natural reproducible resource |
| CN104725633A (en) * | 2014-12-10 | 2015-06-24 | 陆喜 | Preparation method of all-bio-based elastomer |
| CN109467664A (en) * | 2017-09-08 | 2019-03-15 | 汪上晓 | The preparation method of polyurethane resin |
| CN109206155A (en) * | 2018-10-25 | 2019-01-15 | 吉林师范大学 | A method of preparing slow-release carbamide |
Non-Patent Citations (3)
| Title |
|---|
| 《化工百科全书》编辑委员会编: "《化工百科全书 第1卷 锕系元素的锕系后元素-丙烯酰胺聚合物 a-bing》", 31 December 1990, 化学工业出版社 * |
| 席德清等: "《粮食大辞典 第1版》", 31 December 2009, 中国物资出版社 * |
| 郝鹏飞: "五元环状碳酸酯的制备及其应用", 《中国优秀硕士学位论文全文数据库 工程科技I辑》 * |
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| CN113582771A (en) * | 2021-08-24 | 2021-11-02 | 温州医科大学 | Preparation method of slow-release fertilizer based on high polymer |
| CN113582771B (en) * | 2021-08-24 | 2023-11-10 | 温州医科大学 | Preparation method of polymer-based slow-release fertilizer |
| CN115322367A (en) * | 2022-08-23 | 2022-11-11 | 华南理工大学 | Polyurethane prepared based on urea and preparation method and application thereof |
| CN115322367B (en) * | 2022-08-23 | 2023-09-29 | 华南理工大学 | Polyurethane prepared based on urea and preparation method and application thereof |
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