Hindered amine light stabilizer with multi-arm structure and preparation method of hindered amine light stabilizer
By introducing multi-arm structures and intramolecular hydrogen bonds into hindered amine light stabilizers, the problems of rapid migration and easy extraction of light stabilizers in polymer materials are solved, resulting in better photostability and anti-aging effects.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- XIAN TECH UNIV
- Filing Date
- 2025-12-30
- Publication Date
- 2026-04-21
AI Technical Summary
Existing hindered amine light stabilizers have small molecular weights and weak binding forces with polymer materials, resulting in rapid migration and easy extraction of light stabilizers in polymer materials, which affects the light aging resistance of polymer materials.
A multi-arm hindered amine light stabilizer is used, which increases piperidine content and enhances compatibility with polymer materials by introducing three piperidine amine groups into the molecular structure and forming intramolecular hydrogen bonds of triazine and polypiperidine amine structures.
It improves the bonding force between light stabilizers and polymer materials, prolongs the existence time of light stabilizers in materials, enhances light stability performance, and significantly improves the anti-aging effect of polymer materials.
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Figure CN121895288A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of light stabilizers, and particularly relates to a multi-arm hindered amine light stabilizer and its preparation method. Background Technology
[0002] Plastics, coatings and other polymer materials are prone to chemical bond breakage and cross-linking under the combined effects of light, heat and oxygen, resulting in aging problems such as yellowing, cracking and decreased mechanical properties. This reduces their physical and mechanical properties, greatly shortens their service life and even renders them unusable.
[0003] To prevent or delay photoaging, light stabilizers need to be added to polymer materials. Light stabilizers can be classified according to their mechanism of action into free radical scavengers, ultraviolet absorbers, light shielding agents, and quenchers. Among them, hindered amine light stabilizers can effectively capture free radicals generated in polymer materials during photoaging, preventing the development of chain reactions, thereby improving the aging resistance of polymer materials and extending their service life. Hindered amine light stabilizers are currently an effective additive for preventing photoaging of polymer materials.
[0004] In most hindered amine light stabilizers, the low content of piperidine amine, which plays a major role, results in a weak light stabilizing effect. In long-term outdoor use or in environments with stringent light stability requirements, it may not provide sufficient and long-lasting protection. In addition, due to the small molecular weight of the light stabilizer and its weak binding force with polymer materials, the light stabilizer is prone to rapid migration and extraction from the polymer material, which leads to the loss of the light stabilizer and affects the photoaging resistance of the polymer material. Summary of the Invention
[0005] The purpose of this invention is to provide a multi-arm hindered amine light stabilizer and its preparation method, in order to solve the problems that light stabilizers are prone to rapid migration and extraction in polymer materials due to their small molecular weight and weak binding force with polymer materials, which leads to the loss of light stabilizers and affects the photoaging resistance of polymer materials.
[0006] This invention adopts the following technical solution: a multi-arm hindered amine light stabilizer, the structural formula of which is:
[0007]
[0008] A method for preparing a multi-arm hindered amine light stabilizer, the preparation process of which is as follows:
[0009]
[0010] The beneficial effects of this invention are:
[0011] This invention constructs a hindered amine photostable agent with a multi-arm structure by exchanging piperidine amines with different substituents. It introduces three piperidine amine groups into the molecular structure, increases the piperidine content, and provides more effective reaction units. At the same time, the triazine and polypiperidine amine structures form intramolecular hydrogen bonds, producing a self-synergistic effect. It has both ultraviolet absorption and free radical scavenging functions, resulting in superior photostable performance.
[0012] This invention relates to hindered amine light stabilizers with cage-like multi-arm structures constructed by exchanging piperidine amines with different substituents. These stabilizers have good compatibility with polymer materials, can remain stable in materials for a long time, are not easily migrated or extracted, and can effectively extend the service life of polymer materials. Attached Figure Description
[0013] Figure 1 The proton NMR spectrum of the multi-arm hindered amine light stabilizer synthesized in Example 1 of this invention;
[0014] Figure 2 Mass spectrometry of the multi-arm hindered amine light stabilizer synthesized in Example 1 of this invention;
[0015] Figure 3 The relationship (%) between aging time and tensile strength retention rate of the multi-arm structure hindered amine light stabilizer synthesized in Example 1 of the present invention with an addition amount of 0.3% is shown.
[0016] Figure 4 The relationship between aging time and elongation at break retention (%) for the multi-arm hindered amine light stabilizer synthesized in Example 1 with an addition amount of 0.3%. Detailed Implementation
[0017] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.
[0018] This invention discloses a multi-arm hindered amine light stabilizer, the structural formula of which is:
[0019]
[0020] This invention also discloses a method for preparing a multi-arm hindered amine light stabilizer, the preparation process of which is as follows:
[0021]
[0022] Specifically:
[0023] Step 1: Using N-n-butyl-2,2,6,6-tetramethyl-4-piperidinamine (1) and 2,4,6-trichloro-1,3,5-triazine (2) as raw materials, 2-chloro-4,6-di-[N-n-butyl-N-(2,2,6,6-tetramethyl-4-piperidinyl)amino]-1,3,5-triazine (3) was synthesized by nucleophilic substitution;
[0024] Step 2: Add 30% aqueous hydrogen peroxide solution dropwise to 2-chloro-4,6-di-[N-n-butyl-N-(2,2,6,6-tetramethyl-4-piperidinyl)amino]-1,3,5-triazine (3) to obtain intermediate (4);
[0025] Step 3: Using intermediate (4) and cyclohexane as raw materials, intermediate (5) is obtained through reaction;
[0026] Step 4: The intermediate (5) and N-n-butyl-2,2,6,6-tetramethyl-4-piperidineamine (1) were heated and reacted under N2 protection to obtain a hindered amine light stabilizer with a multi-arm structure constructed by alkylpiperidineamine exchange.
[0027] The molar ratio of N-n-butyl-2,2,6,6-tetramethyl-4-piperidinamine (1) to 2,4,6-trichloro-1,3,5-triazine (2) is 2:1.
[0028] The molar ratio of intermediate (5) to N-n-butyl-2,2,6,6-tetramethyl-4-piperidinamine (1) is 1:1.1-2.0.
[0029] In the first step of the reaction, the solvent is toluene or xylene, the catalyst is a 10-30% aqueous solution of sodium hydroxide / potassium hydroxide, and the reaction conditions are 70-90℃ for 12-14 hours.
[0030] In the second step of the reaction, the solvent is methanol or acetonitrile, and the reaction conditions are 25-35℃ for 24 hours. A light pink solid appears in the system, and the reaction continues for another 5-10 hours.
[0031] In the third step of the reaction, the solvent is methanol, and the catalysts are ferrous sulfate, glacial acetic acid, and TBHP. The reaction conditions are as follows: 30% hydrogen peroxide is slowly added dropwise to the reaction flask at 65-85℃ over 3 hours, and the reaction continues for 15 hours after the addition is completed.
[0032] In the fourth step of the reaction, the reaction solvent is one of toluene, xylene, or benzene, the catalyst is a 10-30% NaOH aqueous solution or a 30% NaHCO3 aqueous solution, and the reaction conditions are 110-160℃ for 18-24 hours.
[0033] The present invention also discloses the use of a multi-arm structure hindered amine light stabilizer for preparing PE film, wherein the addition amount is 0.3%.
[0034] Example 1
[0035] 18.44 g of 2,4,6-trichloro-1,3,5-triazine was dissolved in 200 mL of toluene. Under an ice-water bath, 42.42 g of N-n-butyl-2,2,6,6-tetramethyl-4-piperidinamine was slowly added, and the reaction was allowed to proceed for 2 h. Then, 30% NaOH aqueous solution was added dropwise, and the reaction was continued at 70 °C for 14 h. After the reaction was complete, 200 mL of water was added and the mixture was extracted three times to separate the organic phase. The organic phase was dried over anhydrous sodium sulfate, the solvent was removed by rotary evaporation, and the product was dried under vacuum to obtain intermediate (3), with a yield of approximately 46.2 g and a yield of 86%.
[0036] 3.567 g of intermediate (3) was dissolved in 60 mL of methanol and stirred at 15 °C for 10 min. Then, 6 mL of 30% hydrogen peroxide aqueous solution was slowly added dropwise. After the temperature was raised to 25 °C and the reaction was continued for 24 h, a light pink solid appeared in the system. After the reaction was continued for 5 h, the solid product was collected by vacuum filtration and dried in a vacuum drying oven at 35 °C for 8 h to obtain intermediate (4), with a yield of about 2.98 g and a yield of 80%.
[0037] In a 1000mL three-necked flask, 6g of intermediate (4) was dissolved in 600mL of methanol at room temperature by sonication. Then, 150mL of cyclohexane, 1.5255g of FeSO4, 15mL of water, 0.9mL of glacial acetic acid, and 2.625g of TBHP were added sequentially. The mixture was stirred at 55℃ for 0.5h. The temperature of the mixture was raised to 65℃, and 51.3mL of 30% hydrogen peroxide was slowly added dropwise to the reaction flask over 3h. After the addition was completed, the reaction was continued for 15h, and samples were taken for analysis until the mixture was qualified. After cooling naturally to room temperature, solid impurities were filtered off. Dichloromethane and water were added to the reaction solution for extraction. The organic phase was collected, and the crude product was obtained by rotary evaporation and vacuum drying. The crude product was purified by column chromatography to obtain intermediate (5), with a yield of about 4.7g and a yield of 61%.
[0038] 18.289 g of intermediate (5), 5.85 g of N-butyl-2,2,6,6-tetramethyl-4-piperidinamine, 3.35 g of NaOH aqueous solution (10%) and 200 mL of toluene were placed in a flask and heated in an oil bath at 110 °C for 24 h under nitrogen protection. After the reaction was completed, the mixture was cooled to room temperature, and the organic phase was washed three times with 50 mL of water. The mixture was then dried with anhydrous sodium sulfate to obtain the crude product. The crude product was further purified by column chromatography to obtain a hindered amine light stabilizer with a cage-like multi-arm structure constructed by alkylpiperidinamine exchange. The yield was 17.6 g, with a yield of 78%.
[0039] The hindered amine light stabilizer prepared in Example 1 was added at a concentration of 0.3% to prepare PE film. Meanwhile, a PE film without the hindered amine light stabilizer of this example was used as a blank control. The effect of artificial climate aging on the mechanical properties of the PE film was tested according to the national standard GB / T 16422.3-2022. The specific data are shown in Tables 1-6.
[0040] Table 1
[0041]
[0042] Table 2
[0043]
[0044]
[0045] Table 3
[0046]
[0047] Table 4
[0048]
[0049] Table 5
[0050]
[0051]
[0052] Table 6
[0053]
[0054] As can be seen from Tables 1-6, compared with the film without the hindered amine light stabilizer prepared in this embodiment, the film with a low content of light stabilizer can significantly improve the anti-aging effect of the PE film.
[0055] The 1H NMR spectrum of the hindered amine light stabilizer prepared in Example 1 is as follows: Figure 1 As shown, the results are as follows: 1 HNMR (600MHz, CDCl3) δ5.74-4.75(m,4H),3.60(s,2H),3.44-2.96(m,6H),2.05(s,5H),1.79-0.35(m,84H).
[0056] The mass spectra of the hindered amine light stabilizer synthesized in Example 1 are as follows: Figure 2 As shown, the results are as follows: MS(ESI), m / z: 911.8043[M+H]+.
[0057] Example 2
[0058] 18.44 g of 2,4,6-trichloro-1,3,5-triazine was dissolved in 200 mL of xylene. Under an ice-water bath, 42.42 g of N-n-butyl-2,2,6,6-tetramethyl-4-piperidinamine was slowly added, and the reaction was allowed to proceed for 2 h. Then, 10% NaOH aqueous solution was added dropwise, and the reaction was continued at 70 °C for 14 h. After the reaction was complete, 200 mL of water was added and the mixture was extracted three times to separate the organic phase. The organic phase was dried over anhydrous sodium sulfate, the solvent was removed by rotary evaporation, and the product was dried under vacuum to obtain intermediate (3), with a yield of approximately 36.53 g and a yield of 68%.
[0059] 3.567 g of intermediate (3) was dissolved in 60 mL of acetonitrile and stirred at 15 °C for 10 min. Then, 6 mL of 30% hydrogen peroxide aqueous solution was slowly added dropwise. After the temperature was raised to 25 °C and the reaction was continued for 24 h, a light pink solid appeared in the system. After the reaction was continued for 5 h, the solid product was collected by vacuum filtration and dried in a vacuum drying oven at 35 °C for 8 h to obtain intermediate (4), with a yield of about 2.87 g and a yield of 77%.
[0060] In a 1000mL three-necked flask, 6g of intermediate (4) was dissolved by sonication in 600mL of acetonitrile at room temperature. Then, 150mL of cyclohexane, 1.5255g of FeSO4, 15mL of water, 0.9mL of glacial acetic acid, and 2.625g of TBHP were added sequentially. The mixture was stirred at 55℃ for 0.5h. The temperature of the mixture was raised to 65℃, and 51.3mL of 30% hydrogen peroxide was slowly added dropwise to the reaction flask over 3h. After the addition was completed, the reaction was continued for 15h, and samples were taken for analysis until the mixture was qualified. After cooling naturally to room temperature, solid impurities were filtered off. Dichloromethane and water were added to the reaction solution for extraction. The organic phase was collected, and the crude product was obtained by rotary evaporation and vacuum drying. The crude product was purified by column chromatography to obtain intermediate (5), with a yield of about 4.24g and a yield of 55%.
[0061] 18.289 g of intermediate (5), 8.48 g of N-butyl-1,2,2,6,6-pentamethylpiperidin-4-amine, 3.35 g of NaOH aqueous solution (30%) and 200 mL of xylene were placed in a flask and heated in an oil bath at 140 °C for 18 h under nitrogen protection. After the reaction was completed, the mixture was cooled to room temperature, and the organic phase was washed three times with 50 mL of water. The mixture was then dried with anhydrous sodium sulfate to obtain the crude product. The crude product was further purified by column chromatography to obtain a hindered amine light stabilizer with a cage-like multi-arm structure constructed by alkylpiperidinamine exchange. The yield was 12.5 g, with a yield of 54%.
[0062] Example 3
[0063] 18.44 g of 2,4,6-trichloro-1,3,5-triazine was dissolved in 200 mL of toluene. Under an ice-water bath, 42.42 g of N-n-butyl-2,2,6,6-tetramethyl-4-piperidinamine was slowly added, and the reaction was allowed to proceed for 2 h. Then, 30% NaOH aqueous solution was added dropwise, and the reaction was continued at 80 °C for 14 h. After the reaction was complete, 200 mL of water was added and the mixture was extracted three times to separate the organic phase. The organic phase was dried over anhydrous sodium sulfate, the solvent was removed by rotary evaporation, and the product was dried under vacuum to obtain intermediate (3), with a yield of approximately 40.29 g and a yield of 75%.
[0064] 3.567 g of intermediate (3) was dissolved in 60 mL of methanol and stirred at 15 °C for 10 min. Then, 6 mL of 30% hydrogen peroxide aqueous solution was slowly added dropwise. After the temperature was raised to 25 °C and the reaction was continued for 24 h, a light pink solid appeared in the system. After the reaction was continued for 10 h, the solid product was collected by vacuum filtration and dried in a vacuum drying oven at 35 °C for 8 h to obtain intermediate (4), with a yield of about 2.64 g and a yield of 71%.
[0065] In a 1000mL three-necked flask, 6g of intermediate (4) was dissolved in 600mL of methanol at room temperature by sonication. Then, 150mL of cyclohexane, 1.5255g of FeSO4, 15mL of water, 0.9mL of glacial acetic acid, and 2.625g of TBHP were added sequentially. The mixture was stirred at 65℃ for 0.5h. The temperature of the mixture was raised to 85℃, and 51.3mL of 30% hydrogen peroxide was slowly added dropwise to the reaction flask over 3h. After the addition was completed, the reaction was continued for 15h, and samples were taken for analysis until the mixture was qualified. After cooling naturally to room temperature, solid impurities were filtered off. Dichloromethane and water were added to the reaction solution for extraction. The organic phase was collected, and the crude product was obtained by rotary evaporation and vacuum drying. The crude product was purified by column chromatography to obtain intermediate (5), with a yield of about 3.7g and a yield of 48%.
[0066] 18.289 g of intermediate (5), 13.51 g of N-butyl-2,2,6,6-tetramethyl-1-propoxypiperidine-4-amine, 3.35 g of NaOH aqueous solution (30%) and 200 mL of toluene were placed in a flask and heated in an oil bath at 160 °C for 20 h under nitrogen protection. After the reaction was completed, the mixture was cooled to room temperature, and the organic phase was washed three times with 50 mL of water. The mixture was then dried with anhydrous sodium sulfate to obtain the crude product. The crude product was further purified by column chromatography to obtain a hindered amine light stabilizer with a cage-like multi-arm structure constructed by alkylpiperidine amine exchange. The yield was 14.4 g, with a yield of 61%.
[0067] Example 4
[0068] 18.44 g of 2,4,6-trichloro-1,3,5-triazine was dissolved in 200 mL of toluene. Under an ice-water bath, 42.42 g of N-n-butyl-2,2,6,6-tetramethyl-4-piperidinamine was slowly added, and the reaction was allowed to proceed for 2 h. Then, 30% NaOH aqueous solution was added dropwise, and the reaction was continued at 70 °C for 12 h. After the reaction was complete, 200 mL of water was added and the mixture was extracted three times to separate the organic phase. The organic phase was dried over anhydrous sodium sulfate, the solvent was removed by rotary evaporation, and the product was dried under vacuum to obtain intermediate (3), with a yield of approximately 33.84 g and a yield of 63%.
[0069] 3.567 g of intermediate (3) was dissolved in 60 mL of methanol and stirred at 15 °C for 10 min. Then, 6 mL of 30% hydrogen peroxide aqueous solution was slowly added dropwise. After the temperature was raised to 35 °C and the reaction was continued for 24 h, a light pink solid appeared in the system. After the reaction was continued for 5 h, the solid product was collected by vacuum filtration and dried in a vacuum drying oven at 35 °C for 8 h to obtain intermediate (4), with a yield of about 2.16 g and a yield of 58%.
[0070] In a 1000mL three-necked flask, 6g of intermediate (4) was dissolved in 600mL of methanol at room temperature by sonication. Then, 250mL of cyclohexane, 1.5255g of FeSO4, 15mL of water, 0.9mL of glacial acetic acid, and 2.625g of TBHP were added sequentially. The mixture was stirred at 55℃ for 0.5h. The temperature of the mixture was raised to 65℃, and 51.3mL of 30% hydrogen peroxide was slowly added dropwise to the reaction flask over 3h. After the addition was completed, the reaction was continued for 15h, and samples were taken for analysis until the mixture was qualified. After cooling naturally to room temperature, solid impurities were filtered off. Dichloromethane and water were added to the reaction solution for extraction. The organic phase was collected, and the crude product was obtained by rotary evaporation and vacuum drying. The crude product was purified by column chromatography to obtain intermediate (5), with a yield of about 4.62g and a yield of 60%.
[0071] 18.289 g of intermediate (5), 8.55 g of 1-cyclohexyloxy-2,2,6,6-tetramethyl-N-butyl-4-piperidineamine, 7.046 g of NaHCO3 aqueous solution (30%) and 200 mL of benzene were placed in a flask and reacted in an oil bath at 160 °C for 18 h under nitrogen protection. After the reaction was completed, the mixture was cooled to room temperature, and the organic phase was washed three times with 50 mL of water. The mixture was then dried with anhydrous sodium sulfate to obtain the crude product. The crude product was further purified by column chromatography to obtain a hindered amine light stabilizer with a cage-like multi-arm structure constructed by alkylpiperidineamine exchange. The yield was 14.6 g, with a yield of 58%.
[0072] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. A multi-arm hindered amine light stabilizer, characterized in that, Its structural formula is:
2. A method for preparing a multi-arm hindered amine light stabilizer, characterized in that, Its preparation process is as follows:
3. The method for preparing a multi-arm hindered amine light stabilizer according to claim 2, characterized in that, The molar ratio of N-n-butyl-2,2,6,6-tetramethyl-4-piperidineamine (1) to 2,4,6-trichloro-1,3,5-triazine (2) is 2:
1.
4. The method for preparing a multi-arm hindered amine light stabilizer according to claim 2, characterized in that, The molar ratio of intermediate (5) to N-n-butyl-2,2,6,6-tetramethyl-4-piperidineamine (1) is 1:1.1-2.
0.
5. The method for preparing a multi-arm hindered amine light stabilizer according to claim 2, characterized in that, The reaction solvent in the first step is toluene or xylene, the catalyst is a 10-30% aqueous solution of sodium hydroxide / potassium hydroxide, and the reaction conditions are 70-90℃ for 12-14 hours.
6. The method for preparing a multi-arm hindered amine light stabilizer according to claim 2, characterized in that, In the second step, the solvent is methanol or acetonitrile. The reaction conditions are 25-35℃ for 24 hours. A light pink solid appears in the system. Continue the reaction for another 5-10 hours.
7. The method for preparing a multi-arm hindered amine light stabilizer according to claim 2, characterized in that, In the third step of the reaction, the solvent is methanol, and the catalysts are ferrous sulfate, glacial acetic acid, and TBHP. The reaction conditions are: 30% hydrogen peroxide is slowly added dropwise to the reaction flask over 3 hours at 65-85℃, and the reaction continues for 15 hours after the addition is completed.
8. The method for preparing a multi-arm hindered amine light stabilizer according to claim 2, characterized in that, In the fourth step of the reaction, the solvent is one of toluene, xylene, or benzene, the catalyst is a 10-30% NaOH aqueous solution or a 30% NaHCO3 aqueous solution, and the reaction conditions are 110-160℃ for 18-24 hours.
9. The use of multi-arm structure hindered amine light stabilizers, characterized in that, It is used to prepare PE film, and the addition amount is 0.3%.