Method for synthesizing polymer type hindered amine light stabilizer
By forming a dichlorotriazine intermediate under alkaline conditions and polycondensing it with a piperidine diamine compound, combined with acidic gas treatment and subsequent extraction steps, the problem of excessive polymers in the preparation of existing light stabilizers is solved, achieving high light transmittance and simplified process.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HENGSHUI KAIYA CHEM
- Filing Date
- 2025-12-24
- Publication Date
- 2026-05-19
AI Technical Summary
Existing methods for preparing light stabilizer 3346 involve cumbersome and complex steps, produce a large number of polymers, and are difficult to react. The polymers are also difficult to remove completely, affecting the light transmittance and application performance of the product.
The method involves reacting cyanuric chloride with morpholine under alkaline conditions to form a dichlorotriazine intermediate of morpholine, which is then polycondensed with piperidine diamine. By controlling the reaction conditions and solvent dosage, the formation of polymers is reduced. The polymer residue is further reduced through acid gas treatment and subsequent extraction, water washing, and solvent removal steps.
It effectively controls the residual amount of polymers, increases the light transmittance of the product to over 98%, simplifies the preparation process, and reduces energy consumption and reaction time.
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Figure CN122060159A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of additive technology, and specifically to a method for preparing a polymeric hindered amine light stabilizer. Background Technology
[0002] Polymer materials play an increasingly important role in the national economy and industrial and agricultural production, but their greatest weakness—aging—significantly limits their development and application. Photoaging poses a fatal threat to polymer materials, especially synthetic materials used outdoors, severely restricting their widespread application. Light stabilizers can inhibit and resist the adverse effects of light on polymer materials, playing a crucial role in extending their lifespan. Light stabilizers can inhibit the photo-oxidative degradation reaction of polymers by shielding and absorbing ultraviolet light, quenching excitation energy, and capturing free radicals, thereby giving products good light stability and extending their service life. They include light shielding agents, ultraviolet absorbers, quenchers, and free radical scavengers. Hindered amine light stabilizers have advantages such as high efficiency, low toxicity, low cost, and good compatibility with polymer materials, and are therefore widely used in various organic polymer materials. They absorb almost no ultraviolet light and mainly protect polymer materials from photoaging by capturing free radicals, decomposing peroxides, and transferring excited-state energy; they are currently recognized as highly efficient light stabilizers. Since the 1970s, after years of development, a considerable number of hindered amine light stabilizers have been produced, with a wide variety of types and applications.
[0003] Light stabilizer 3346 is a novel, highly efficient polymeric hindered amine light stabilizer introduced by Cytec in the early 1990s. Its structural unit consists of a triazine derivative and a hindered amine group, and it has the following structure: Where n is the degree of aggregation, which is usually an integer between 2 and 12.
[0004] Light stabilizer 3346 is widely used in PE (polyethylene) and PP (polypropylene) materials. For example, it is used in PE films, filaments, injection molded and rotational molded products, sheets, and metallocenes; and in PP films, filaments, fibers, injection molded products, and TPO (thermoplastic polyolefins). It effectively enhances the light resistance of these products and extends their service life. Due to its high relative molecular mass, light stabilizer 3346 exhibits good extraction resistance during processing and use, is not easily lost, and is often used in combination with light stabilizer 622.
[0005] Currently, the methods for preparing light stabilizer 3346 are cumbersome and complex, resulting in a large amount of polymers in the obtained light stabilizer 3346. Furthermore, the use of segmented heating is complicated, the reaction is difficult, and the polymers are hard to remove completely. Summary of the Invention
[0006] In a first aspect, this application provides a method for synthesizing a polymeric hindered amine light stabilizer, comprising: S1. In a first solvent, in the presence of a first base, cyanuric chloride and morpholine undergo a first reaction to obtain a first intermediate solution; S2. Add a second solvent, a second base, and a piperidine diamine compound of formula II to the first intermediate solution to carry out a second reaction, thereby obtaining the polymeric hindered amine light stabilizer of formula I; (I) (II) Where R is the same or different, each is independently represented by C. 1-6 alkyl; a is an integer from 1 to 10; n represents the degree of polymerization of the hindered amine light stabilizer of polymer type I.
[0007] In some embodiments, the hindered amine light stabilizer of formula I has a number-average molecular weight of 900-1600, a weight-average molecular weight of 1800-3200, and a molecular weight distribution of 1.5-2.3; and / or In the polymer-type hindered amine light stabilizer of Formula I, the proportion of polymers with a molecular weight greater than 3500 is less than 5%, preferably, the proportion of polymers with a molecular weight greater than 4500 is less than 1%, based on the total weight of the polymer-type hindered amine light stabilizer of Formula I.
[0008] In some embodiments, the reaction temperature of the first reaction is -5 to 80°C, and the reaction pressure can be atmospheric pressure; And / or, the reaction temperature of the second reaction is 120~160℃, for example 150~160℃, and the reaction pressure is 0.45~0.54MPa; And / or, the first solvent and the second solvent may be the same or different, and are selected from one or more of xylene, toluene, n-octane, dichloroethane, and S-100 solvent oil; preferably, the second solvent is the same as the first solvent; And / or, the amount of the first solvent is 2.5-3.5 times the molar amount of cyanuric chloride, and the mass of the second solvent is 1-2.5 times the mass of the first solvent, preferably 1-1.5 times.
[0009] In some implementations, S1 includes: S11. In a reactor containing a slurry of cyanuric chloride as the first solvent, a first solvent solution of morpholine, a first alkali solution, and water are added sequentially, wherein the temperature of the reactor is controlled at a first temperature during the addition process; S12. Raise the reactor temperature to the second temperature to continue the first reaction and obtain the first reaction product; S13. Remove water from the first reaction product obtained in S12 to obtain the first intermediate solution.
[0010] Preferably, the concentration of morpholine in the first solvent solution is 40-50 wt%; And / or, the first alkaline solution is selected from one or more of potassium hydroxide solution, sodium hydroxide solution, sodium carbonate solution, and sodium bicarbonate; And / or, the amount of morpholine used is 0.95-1.01 times the molar amount of cyanuric chloride; And / or, the first temperature is -5~10℃, and the second temperature is 30~80℃.
[0011] In some implementations, S2 includes: S21. At a third temperature, a second solvent and the piperidine diamine compound of formula II are added to the first intermediate solution, followed by the addition of a second alkaline solution and water in sequence; S22. The mixture obtained in S21 is subjected to a second reaction at a fourth temperature to obtain the second reaction contents; Preferably, the third temperature is 60~80℃, and the fourth temperature is 120~160℃; And / or, the second alkaline solution is selected from one or more of potassium hydroxide solution, sodium hydroxide solution, sodium carbonate, and sodium bicarbonate; And / or, the concentration of the second alkaline solution is 20-30 wt%; And / or, the amount of piperidine diamine compound of formula II is 1 to 1.1 times the molar amount of cyanuric chloride.
[0012] In some embodiments, the method further includes: S31. Acidic gas is introduced into the second reaction contents of S2 for treatment, and... S32. Post-processing steps for the material obtained in S31; Preferably, the acidic gas is selected from one or more of CO2 gas, hydrogen chloride gas, and chlorine gas; And / or, the temperature of S31 is 20-75°C, preferably 55-75°C.
[0013] The post-processing includes: filtration, extraction, washing with water, and solvent removal.
[0014] Secondly, this application also relates to polymeric hindered amine light stabilizers of formula I. (I) Where R is the same or different, each is independently represented by C. 1-6 alkyl; a is an integer from 1 to 10; n represents the degree of polymerization of the hindered amine light stabilizer of polymer type I, which is an integer from 2 to 12; The hindered amine light stabilizer of Formula I has a number-average molecular weight of 900-1600, a weight-average molecular weight of 1800-3200, and a molecular weight distribution of 1.5-2.3. In the polymer-type hindered amine light stabilizer of Formula I, the proportion of polymers with a molecular weight greater than 3500 is less than 5%, preferably, the proportion of polymers with a molecular weight greater than 4500 is less than 1%, based on the total weight of the polymer-type hindered amine light stabilizer of Formula I.
[0015] The method of this application first involves a substitution reaction between cyanuric chloride and morpholine under alkaline conditions to form a dichlorotriazine intermediate of morpholine. Then, the intermediate undergoes polycondensation to obtain the corresponding polymeric hindered amine light stabilizer. After the first reaction, this method eliminates the need for a purification step and allows direct entry into the subsequent second reaction. By adding a certain amount of a second solvent to the intermediate solution obtained from the first reaction, the excessive formation of polymers during the second reaction can be avoided, thereby effectively controlling the final polymer residue. Detailed Implementation
[0016] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. The specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the invention in any way.
[0017] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments.
[0018] Furthermore, the technical features involved in the different embodiments of this application described below can be combined with each other as long as they do not conflict with each other.
[0019] In the field of polymer material additives, the performance of hindered amine light stabilizers determines their application areas, as well as the photoaging and weather resistance of materials. Light stabilizer 3346, as a polymeric hindered amine light stabilizer, suffers from low light transmittance due to its high polymer content, directly affecting its application performance. The technical solution of this invention produces a product with low polymer content and a light transmittance of over 98%.
[0020] This application provides a method for synthesizing a polymer type I hindered amine light stabilizer, comprising: S1. In a first solvent, in the presence of a first base, cyanuric chloride and morpholine undergo a first reaction to obtain a first intermediate solution; S2. Add a second solvent, a second base, and a piperidine diamine compound of formula II to the first intermediate solution to carry out a second reaction, thereby obtaining the polymeric hindered amine light stabilizer of formula I; (I) (II) Where R is the same or different, each is independently represented by C. 1-6 alkyl; a is an integer from 1 to 10; n represents the degree of polymerization of the hindered amine light stabilizer of polymer type I.
[0021] In some implementations, R is the same, and is C. 1-3 Alkyl groups, preferably methyl groups. In some embodiments, a is 4-8, preferably 6. In some embodiments, n is an integer from 2 to 12. When all R are methyl groups and a is 6, the polymeric hindered amine light stabilizer of formula I is light stabilizer 3346.
[0022] In some embodiments, the number-average molecular weight of the polymeric hindered amine light stabilizer of Formula I is 900-1600, the weight-average molecular weight is 1800-3200, and the molecular weight distribution is 1.5-2.3.
[0023] The method of this application first involves a substitution reaction between cyanuric chloride and morpholine under alkaline conditions to form a dichlorotriazine intermediate of morpholine. Then, the intermediate is polycondensed with a piperidine diamine compound of formula II under alkaline conditions to form a polymer chain, thereby obtaining the corresponding polymeric hindered amine light stabilizer.
[0024] In some embodiments of the method of this application, the reaction temperature for the first reaction to form dichlorotriazine is -5 to 80°C, and the pressure is atmospheric pressure. Under these reaction conditions, the dichlorotriazine intermediate can be rapidly formed. After the first reaction, the mixture obtained from the first reaction can be treated, such as by dehydration, to remove excess alkali from the first reaction. Then, the intermediate undergoes a second reaction of polycondensation to form polymer chains. At this point, it is necessary to increase the amount of solvent in the second reaction (i.e., add a second solvent) and reduce the reaction time, which can reduce the proportion of polymer in the final product.
[0025] In some embodiments, the reaction temperature of the first reaction can be -5 to 80°C, for example, 0 to 30°C, 5 to 25°C, or 3°C, 10°C, 15°C, 20°C, 25°C, 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C, or 75°C. Conducting the first reaction for the synthesis of the dichlorotriazine intermediate under these low-temperature conditions reduces energy consumption and avoids extensive hydrolysis of cyanuric chloride, thereby effectively ensuring the material balance of the second reaction. In some embodiments, the first reaction can be carried out under atmospheric pressure.
[0026] In some embodiments, the proportion of polymers with a molecular weight greater than 3500 in the Formula I polymer-type hindered amine light stabilizer is less than 5%, for example less than 4% or less than 3.7%. Preferably, the proportion of polymers with a molecular weight greater than 4500 is less than 1%, for example less than 0.6%, based on the total weight of the Formula I polymer-type hindered amine light stabilizer.
[0027] In some implementations, S1 includes: S11. In a reactor containing a slurry of cyanuric chloride as the first solvent, a first solvent solution of morpholine, a first alkali solution, and water are added sequentially, wherein the temperature of the reactor is controlled at a first temperature during the addition process; S12. Raise the reactor temperature to the second temperature to continue the first reaction and obtain the first reaction product; S13. Remove water from the first reaction product obtained in S12 to obtain the first intermediate solution.
[0028] In one embodiment, in step S11, cyanuric chloride is pulped in a first solvent to form a cyanuric chloride slurry in the first solvent. In one embodiment, the first solvent is selected from one or more of xylene, toluene, dichloroethane, n-octane, and solvent S-100; and / or, the amount of the first solvent is 2.5-3.5 times the molar amount of cyanuric chloride. Using these first solvents and their amounts allows for better dispersion and more complete reaction of the cyanuric chloride. Pulping can be carried out at a certain temperature, for example, 10-50°C (e.g., 25-35°C).
[0029] Next, the slurry of cyanuric chloride in the first solvent is transferred to the reactor, and the first solvent solution of morpholine, the first alkali solution, and water are added sequentially to the reactor to carry out the first reaction. This reactor can be a glass reactor, and the first reaction is carried out in an inert atmosphere. An inert atmosphere can be formed by purging nitrogen gas.
[0030] In some embodiments, the amount of morpholine used is 0.95-1.01 times, for example, 0.98-1.00 times, the molar amount of cyanuric chloride. In some embodiments, the concentration of the first solvent solution of morpholine is 40-50%, for example, 45-50 wt%.
[0031] In some embodiments, the first alkaline solution is selected from one or more of potassium hydroxide solution, sodium hydroxide solution, sodium carbonate, and sodium bicarbonate; and / or, the concentration of the first alkaline solution is 20-35 wt%, for example, 20-30 wt%. In some embodiments, the amount of the first alkaline solution used is 0.5-1.2 times the mass of cyanuric chloride. In some embodiments, the amount of pure water used is 1-1.2 times the molar mass of cyanuric chloride.
[0032] Adding a first alkali solution can effectively neutralize the generated HCl and reduce energy consumption. Both the addition of the first solvent solution of morpholine and the addition of the first alkali solution in S11 can be carried out dropwise to prevent vigorous reaction leading to rapid temperature changes and overheating. In some embodiments, the reactor temperature is controlled during the addition process at a first temperature, which can be -5 to 15°C, for example, 0 to 10°C, -5 to 5°C, etc. This also helps prevent vigorous reaction leading to rapid temperature changes and overheating.
[0033] The reactor temperature is then raised to a second temperature to continue the first reaction, yielding the first reaction product. In some embodiments, the second temperature is 30–80°C. Continuing the reaction at this second temperature can improve the conversion rate, shorten the reaction time, and also help reduce the proportion of polymers.
[0034] In S13, after the first reaction is completed, the product of the first reaction is cooled to room temperature and the water is separated to obtain the first intermediate solution. The water separation process removes excess alkaline solution from the first reaction.
[0035] In some implementations, S2 includes: S21. At a third temperature, a second solvent, the piperidine diamine compound of formula II, a second alkaline solution, and water are added to the first intermediate solution; S22. The mixture obtained in S21 is subjected to a second reaction at a fourth temperature to obtain the second reaction contents.
[0036] A second solvent, a piperidine diamine compound of formula II, a second alkaline solution, and water can be added to the first intermediate solution. The entire addition process is controlled at a third temperature and carried out under an inert atmosphere, such as nitrogen protection.
[0037] In some embodiments, in S21, the third temperature is 50-80°C, for example 55-70°C, or 65°C.
[0038] In some embodiments, the second solvent is selected from one or more of xylene, toluene, S-100 solvent oil, petroleum ether, and dichloroethane; preferably, the second solvent is the same as the first solvent. In some embodiments, the amount of the second solvent added is 1 to 2.5 times, for example 1 to 1.5 times, for example 1 to 1.4 times, or for example 1.2 to 1.3 times, of the total amount of the first solvent in the first reaction step.
[0039] In some embodiments, the amount of the piperidine diamine compound of formula II is 1 to 1.1 times, for example 1 to 1.07 times, the molar amount of cyanuric chloride.
[0040] In some embodiments, the second alkaline solution is selected from one or more of potassium hydroxide solution, sodium hydroxide solution, sodium carbonate, and sodium bicarbonate; and / or, the concentration of the second alkaline solution is 20-35 wt%, for example, 20-30 wt%; and / or, the amount of the second alkaline solution is 1-1.2 times the mass of cyanuric chloride; and / or, the amount of the second alkaline solution is equal in mass to the amount of water.
[0041] After the feeding is complete, the second reaction continues at a fourth temperature. This fourth temperature is 150-160°C, for example, 155-160°C, or 158-160°C. Continuing the second polymerization reaction under this temperature condition can significantly shorten the reaction time, increase the product yield, and prevent other side reactions caused by excessively long reaction times, such as the side reaction of hexamethylenediamine cyclization polymerization.
[0042] In some implementations, the reaction pressure for the entire second reaction can be 0.45 to 0.54 MPa.
[0043] In some embodiments, the method further includes: S31. Acidic gas is introduced into the second reaction contents of S2 for treatment, and... S32. Perform post-processing steps on the material obtained in S31.
[0044] In some embodiments, the acidic gas is selected from one or more of CO2 gas, hydrogen chloride gas, and chlorine gas. Preferably, CO2 gas has lower acidity and is easier to remove, and is therefore preferred. In some embodiments, the temperature for processing S31 is 20-80°C, such as 20-75°C, such as 40-75°C, such as 55-75°C; the processing time is 0.2-0.7 h, such as 0.3-0.5 h. Using an acidic gas can react with excess polymer to produce salt, which can then be removed by subsequent water washing, further reducing the final polymer residue; and the temperature of this process should not be too high, otherwise it will affect the light transmittance of the final product.
[0045] In some embodiments, the post-processing includes: filtration, extraction, washing with water, and desolventizing.
[0046] The filtration process removes the reaction products of acidic gases and excess polymers, further reducing the final polymer residue.
[0047] Next, extraction and washing are performed. After extraction, the filtrate can be separated from the water, washed with water to remove salt, and then dehydrated. Dehydration can be carried out under reduced pressure. For example, the dehydration temperature can be 70-85℃, and the vacuum degree can be above 0.08MPa.
[0048] Next, a solvent removal process is performed. The solvent can be removed under reduced pressure at high temperature. For example, the solvent removal temperature is 140-160℃, or 140-150℃, and the vacuum degree is above 0.09MPa, such as 0.09~0.095MPa.
[0049] After solvent removal, the product is cooled and granulated to obtain the corresponding granular product.
[0050] This application also relates to a polymeric hindered amine light stabilizer of formula I. (I) Where R is the same or different, each is independently represented by C. 1-6 alkyl; a is an integer from 1 to 10; n represents the degree of polymerization of the hindered amine light stabilizer of polymer type I; In the polymer-type hindered amine light stabilizer of Formula I, the proportion of polymers with a molecular weight greater than 3500 is less than 5%, preferably, the proportion of polymers with a molecular weight greater than 4500 is less than 1%, based on the total weight of the polymer-type hindered amine light stabilizer of Formula I.
[0051] The polymeric hindered amine light stabilizer can be prepared by the method described in this application, which will not be repeated here.
[0052] The present application will be further described in detail below through embodiments. Through these descriptions, the features and advantages of the present application will become clearer and more apparent.
[0053] In the following embodiments, the method for detecting polymer content is as follows: GPC was used for detection, with tetrahydrofuran as the mobile phase, and the proportion of each component was analyzed after peak separation.
[0054] Example 1 First reaction: Weigh 33.2g of cyanuric chloride and 108.3g of xylene, mix and stir to form a slurry, transfer to a 1L glass four-necked flask and cool to 3℃. Weigh 15.4g of morpholine and 14.3g of xylene and mix in a 50ml constant pressure dropping funnel, and slowly add to the above four-necked flask, keeping the temperature in the four-necked flask at 3℃ during the process. After 3 hours, the morpholine and xylene mixture is completely added. Then, add 26.7g of 32wt% NaOH aqueous solution over 0.5 hours. Next, add 26.7g of ice-cold pure water over 0.5 hours. Then, raise the temperature to 60℃ and keep it at that temperature for 1 hour, always keeping it under N2 protection. After the reaction is complete, separate the water to obtain a morpholine dichlorotriazine solution. Second reaction: The morpholine dichlorotriazine solution was transferred to an autoclave, and 108.3 g of xylene was added. 75.5 g of N,N'-bis(2,2,6,6-tetramethyl-4-piperidinyl)-1,6-hexanediamine (hereinafter referred to as piperidinehexanediamine, where R is methyl and a is 6), 56.2 g of NaOH solution (32 wt%), and 59.7 g of pure water were added to the autoclave. After three N2 purgings, the temperature was raised to 160 °C, and the reaction pressure was increased from 0.09 MPa to 0.5 MPa. The reaction was maintained at this temperature overnight. Afterwards, the mixture was cooled to room temperature and filtered.
[0055] Post-processing: CO2 was then introduced into the mixture obtained from the second reaction at room temperature for 15 minutes. When the pH of the solution reached 7, the reaction solution was filtered. Then, 50 g of xylene and 30 g of water were added. After standing for 15 minutes, the lower layer of water was separated, and the mixture was heated to 75°C. It was washed three times with pure water and subjected to dehydration under reduced pressure for 1 hour. Subsequently, the temperature was raised to 160°C for desolvation under reduced pressure for 2 hours. After cooling to room temperature, light stabilizer 3346 was obtained with a yield of 91.05% and a transmittance of 98% (425 nm). GPC results are as follows: Its number-average molecular weight is 1156, its weight-average molecular weight is 2216, and its molecular weight distribution is 1.917. The content of polymers with a molecular weight greater than 3500 is 1.3%.
[0056] Example 2 First reaction: Weigh 33.6g of cyanuric chloride and 84.92g of xylene, mix and stir to form a slurry, transfer to a four-necked flask and cool to -2℃. Weigh 14.3g of morpholine and 15.1g of xylene and mix in a 50ml constant pressure dropping funnel, and slowly add to the four-necked flask while maintaining the temperature in the flask at 5℃. After 3 hours, the morpholine and xylene mixture is completely added. Then, add 29.1g of 32wt% NaOH solution over 0.5 hours, followed by 26.5g of ice-cold pure water over 0.5 hours. After that, raise the temperature to 60℃ and keep it at that temperature for 1 hour, always under N2 protection. After the reaction is complete, separate the water and cool to room temperature to obtain the morpholine dichlorotriazine intermediate solution.
[0057] Second reaction: The morpholine dichlorotriazine intermediate solution was transferred to an autoclave, and 120g of xylene was added. 75.5g of piperidine hexamethylenediamine, 56.2g of NaOH solution (concentration 32wt%) and 59.7g of pure water were added to the autoclave. After N2 replacement three times, the temperature was raised to 160℃, and the reaction pressure was increased from 0.09MPa to 0.52MPa. The reaction was kept at this temperature overnight, cooled to room temperature, and filtered. Post-processing: CO2 was bubbled into the filtrate obtained from the second reaction at room temperature, and the pH of the solution was measured to be 7. After filtering the reaction solution, it was allowed to stand for 15 minutes, and the lower layer of water was separated. The solution was then heated to 75°C, washed three times with pure water, and subjected to dehydration under reduced pressure for 1 hour. Subsequently, the solution was heated to 160°C and subjected to desolvation under reduced pressure for 2 hours. After cooling to room temperature, light stabilizer 3346 was obtained, with a transmittance of 98% (425 nm) and a yield of 92%. The GPC test results are as follows: Its number-average molecular weight is 1077, its weight-average molecular weight is 2005, and its molecular weight distribution is 1.862. The content of polymers with a molecular weight greater than 3500 is 0.7%.
[0058] Example 3 First reaction: Weigh 33.1g of cyanuric chloride and 110.92g of xylene, mix and stir to form a slurry, transfer to a four-necked flask and cool to 0℃. Weigh 15.5g of morpholine and 14.5g of xylene and mix in a 50ml constant pressure dropping funnel, and slowly add to the four-necked flask while maintaining the temperature in the flask at 3℃. After 3 hours, the morpholine and xylene mixture is completely added. Then, add 28g of 32wt% NaOH over 0.5 hours, followed by 27g of ice-cold pure water over 0.5 hours. After that, raise the temperature to 60℃ and keep it at that temperature for 1 hour, always under N2 protection. After the reaction is complete, cool to room temperature to obtain a morpholine dichlorotriazine intermediate solution. Second reaction: The morpholine dichlorotriazine intermediate solution was transferred to an autoclave, and 150g of xylene was added. 75.3g of piperidine hexamethylenediamine, 56.5g of liquid alkali and 60g of pure water were added to the autoclave. After N2 replacement three times, the temperature was raised to 160℃, and the reaction pressure was increased from 0.08MPa to 0.54MPa. The reaction was kept at this temperature overnight, and then filtered after cooling to room temperature. Post-processing: CO2 was bubbled into the mixture obtained from the second reaction at room temperature, and the pH of the solution was measured to be 7. After filtering the reaction solution, 50 g of xylene and 30 g of pure water were added. After standing for 15 min, the lower layer of water was separated. The mixture was then heated to 75 °C, washed three times with pure water, and dehydrated under reduced pressure for 1 h. Subsequently, the mixture was heated to 160 °C and desolvated under reduced pressure for 2 h. After cooling to room temperature, light stabilizer 3346 was obtained, with a transmittance of 98.17% (425 nm) and a yield of 92.33%. The GPC test results are as follows: Its number-average molecular weight is 1035, its weight-average molecular weight is 1981, and its molecular weight distribution is 1.914. The content of polymers with a molecular weight greater than 3500 is 0.4%.
[0059] Comparative Example 1 The process was carried out according to Example 1, specifically as follows: before the second reaction began, xylene was not added, and the morpholine dichlorotriazine intermediate solution was cooled to room temperature and then transferred to a four-necked flask. Otherwise, it was the same as in Example 1.
[0060] The light stabilizer 3346 obtained had a transmittance of 93.51% (425 nm) and a yield of 97.33%. The GPC test results are as follows: Its number-average molecular weight is 1619, its weight-average molecular weight is 2900, and its molecular weight distribution is 1.791. The content of polymers with a molecular weight greater than 3500 is 7.62%.
[0061] Comparative Example 2 The process was carried out according to Example 1, except that 50g of xylene was removed from the morpholine dichlorotriazine intermediate solution obtained in the first reaction under reduced pressure, cooled to room temperature and transferred to a four-necked flask, and xylene was not added before the second reaction began. Otherwise, it was the same as in Example 1.
[0062] The light stabilizer 3346 obtained had a transmittance of 82.21% (425 nm) and a yield of 97.07%. The GPC test results are as follows: Its number-average molecular weight is 1997, its weight-average molecular weight is 3737, and its molecular weight distribution is 1.871. The content of polymers with a molecular weight greater than 3500 is 12.63%.
[0063] Example 4 The procedure was carried out according to Example 1, except that 50g of xylene was added before the second reaction began, otherwise it was the same as Example 1.
[0064] The light stabilizer 3346 obtained had a transmittance of 93.21% (425 nm) and a yield of 95.47%. The GPC test results are as follows: Its number-average molecular weight is 1507, its weight-average molecular weight is 3452, and its molecular weight distribution is 2.291. The content of polymers with a molecular weight greater than 3500 is 4.11%.
[0065] Example 5 The process was carried out according to Example 1, except that after CO2 was introduced in the post-processing, the temperature was raised to 75°C for treatment.
[0066] The light stabilizer 3346 obtained had a transmittance of 89.9% (425 nm) and a yield of 94.31%. The GPC test results are as follows: Its number-average molecular weight is 1134, its weight-average molecular weight is 2010, and its molecular weight distribution is 1.772. The content of polymers with a molecular weight greater than 3500 is 0.7%.
[0067] Example 6 The process was carried out according to Example 1, except that toluene was used instead of xylene used in the first reaction, the second reaction, and the post-treatment process.
[0068] The light stabilizer 3346 obtained had a transmittance of 98.21% (425 nm) and a yield of 92.49%. The GPC test results are as follows: Its number-average molecular weight is 1149, its weight-average molecular weight is 2204, and its molecular weight distribution is 1.918. The content of polymers with a molecular weight greater than 3500 is 1.33%.
[0069] Example 7 The process was carried out according to Example 1, except that n-octane was used instead of xylene in the second reaction.
[0070] The light stabilizer 3346 obtained had a transmittance of 98.19% (425nm) and a yield of 93.02%. The GPC test results are as follows: Its number-average molecular weight is 1151, its weight-average molecular weight is 2217, and its molecular weight distribution is 1.926. The content of polymers with a molecular weight greater than 3500 is 1.21%.
[0071] Example 8 The process was carried out according to Example 1, except that the amount of piperidine hexamethylenediamine used in the second reaction was increased to 150g.
[0072] The light stabilizer 3346 obtained had a transmittance of 91.79% (425 nm) and a yield of 90.17%. The GPC test results are as follows: Its number-average molecular weight is 1350, its weight-average molecular weight is 3207, and its molecular weight distribution is 2.376. The content of polymers with a molecular weight greater than 3500 is 8.95%.
[0073] Example 9 The process was carried out according to Example 1, except that the amount of piperidine hexamethylenediamine used in the second reaction was reduced to 50g.
[0074] The light stabilizer 3346 obtained had a transmittance of 75.59% (425 nm) and a yield of 80.38%. The GPC test results are as follows: Its number-average molecular weight is 750, its weight-average molecular weight is 1707, and its molecular weight distribution is 2.36. The content of polymers with a molecular weight greater than 3500 is 0.15%.
[0075] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.
Claims
1. A method for synthesizing a polymer-type hindered amine light stabilizer of formula I, comprising: S1. In a first solvent, in the presence of a first base, cyanuric chloride and morpholine undergo a first reaction to obtain a first intermediate solution; S2. Add a second solvent, a second base, and a piperidine diamine compound of formula II to the first intermediate solution to carry out a second reaction, thereby obtaining the polymeric hindered amine light stabilizer of formula I; (AND) (II) Where R is the same or different, each is independently represented by C. 1-6 alkyl; a is an integer from 1 to 10; n represents the degree of polymerization of the hindered amine light stabilizer of polymer type I.
2. The method according to claim 1, wherein, R is the same, and it is C. 1-3 Alkyl group, preferably methyl; and / or, a is 4-8, preferably 6; and / or, n is 2-12.
3. The method according to claim 1, wherein, The hindered amine light stabilizer of Formula I has a number-average molecular weight of 900-1600, a weight-average molecular weight of 1800-3200, and a molecular weight distribution of 1.5-2.
3. And / or, in the polymeric hindered amine light stabilizer of Formula I, the proportion of polymers with a molecular weight greater than 3500 is less than 5%, preferably, the proportion of polymers with a molecular weight greater than 4500 is less than 1%, based on the total weight of the polymeric hindered amine light stabilizer of Formula I.
4. The method according to claim 1, wherein, The reaction temperature for the first reaction is -5 to 80℃; And / or, the reaction temperature of the second reaction is 120~160℃, and the reaction pressure is 0.45~0.54MPa; And / or, the first solvent and the second solvent may be the same or different, and are selected from one or more of xylene, toluene, n-octane, dichloroethane, and S-100 solvent oil; preferably, the second solvent is the same as the first solvent; And / or, the amount of the first solvent is 2.5-3.5 times the molar amount of cyanuric chloride, and the mass of the second solvent is 1-2.5 times the mass of the first solvent, preferably 1-1.5 times.
5. The method according to claim 1, wherein, S1 includes: S11. In a reactor containing a slurry of cyanuric chloride as the first solvent, a first solvent solution of morpholine, a first alkali solution, and water are added sequentially, wherein the temperature of the reactor is controlled at a first temperature during the addition process; S12. Raise the reactor temperature to the second temperature to continue the first reaction and obtain the first reaction product; S13. Remove water from the first reaction product obtained in S12 to obtain the first intermediate solution.
6. The method according to claim 5, wherein, In the first solvent solution of morpholine, the concentration of morpholine is 40-50 wt%. And / or, the first alkaline solution is selected from one or more of potassium hydroxide solution, sodium hydroxide solution, sodium carbonate solution, and sodium bicarbonate; And / or, the amount of morpholine used is 0.95-1.01 times the molar amount of cyanuric chloride; And / or, the first temperature is -5~10℃, and the second temperature is 30~80℃.
7. The method according to claim 1, wherein, S2 includes: S21. At a third temperature, a second solvent and the piperidine diamine compound of formula II are added to the first intermediate solution, followed by the addition of a second alkaline solution and water in sequence; S22. The mixture obtained in S21 is subjected to a second reaction at a fourth temperature to obtain the second reaction contents; Preferably, the third temperature is 60~80℃, and the fourth temperature is 120~160℃; And / or, the second alkaline solution is selected from one or more of potassium hydroxide solution, sodium hydroxide solution, sodium carbonate, and sodium bicarbonate; And / or, the concentration of the second alkaline solution is 20-30 wt%; And / or, the amount of piperidine diamine compound of formula II is 0.8-1.1 times the molar amount of cyanuric chloride.
8. The method according to any one of claims 1-7, wherein, The method further includes: S31. Acidic gas is introduced into the second reaction contents of S2 for treatment, and... S32. Post-processing steps for the material obtained in S31; Preferably, the acidic gas is selected from one or more of CO2 gas, hydrogen chloride gas, and chlorine gas; And / or, the temperature of S31 is 20-75°C, preferably 55-75°C.
9. The method according to claim 8, wherein, The post-processing includes: filtration, extraction, washing with water, and solvent removal.
10. Formula I polymeric hindered amine light stabilizer, (I) in, Whether R is the same or different, each is independently C. 1-6 alkyl; a is an integer from 1 to 10; n represents the degree of polymerization of the hindered amine light stabilizer of polymer type I, which is an integer from 2 to 12; The hindered amine light stabilizer of Formula I has a number-average molecular weight of 900-1600, a weight-average molecular weight of 1800-3200, and a molecular weight distribution of 1.5-2.
3. In the polymer-type hindered amine light stabilizer of Formula I, the proportion of polymers with a molecular weight greater than 3500 is less than 5%, preferably, the proportion of polymers with a molecular weight greater than 4500 is less than 1%, based on the total weight of the polymer-type hindered amine light stabilizer of Formula I.