High-activity hydroxylamine antioxidant and preparation method thereof

Abstract

The invention belongs to the field of synthetic materials, and particularly relates to a high-activity hydroxylamine antioxidant and a preparation method thereof. The high-activity hydroxylamine antioxidant disclosed by the invention is simple in production process, mild in reaction conditions and high in reaction speed; compared with a traditional straight-chain hydroxylamine antioxidant with a single active center, the hydroxylamine antioxidant has the advantages of higher decomposition temperature, smaller addition amount and longer antioxidation effect acting time.

Description

Technical Field

[0001] The present invention belongs to the field of synthetic materials, and particularly relates to a highly active hydroxylamine antioxidant and a preparation method thereof. Background Art

[0002] Due to the absence of phenolic substances, hydroxylamine antioxidants endow products with good resistance to gas-fumigated yellowing, good color stability, and are more effective than traditional hindered phenolic antioxidants. The hydroxylamine antioxidants on the market are mainly represented by lrgastab FS042 produced by BASF. lrgastab FS042 is a new type of high-temperature resistant, highly efficient and multifunctional phenol-free antioxidant with a CAS number of 143925-92-2 and a chemical formula of C 36 H 75 NO and a molecular weight of 538. At present, the use of bis(octadecyl)hydroxylamine as a hydroxylamine antioxidant mainly relies on imports, and there are few relevant research reports at home and abroad. Patent CN113651730A discloses a method for synthesizing bis(octadecyl)hydroxylamine using hydroxylamine hydrochloride, an acid-binding agent and halogenated octadecane, but in the actual application process, there is a problem that triethylamine hydrochloride cannot be completely removed, resulting in low yield, low product purity and poor antioxidant effect. Patent CN102952308B discloses a method for preparing bis(octadecyl)hydroxylamine using N,N-dialkylamine and hydrogen peroxide under heating reaction. Since hydrogen peroxide is extremely unstable under heating, there is a risk of explosion during large-scale preparation. The hydroxylamine antioxidant disclosed in the present invention has a large difference in structure from bis(octadecyl)hydroxylamine, with a decomposition temperature reaching more than three hundred degrees Celsius and better antioxidant effect. Summary of the Invention

[0003] The main content of the present invention is to provide a highly active hydroxylamine antioxidant and a preparation method thereof according to the deficiencies of the prior art, including a multi-active center hydroxylamine antioxidant and a single-active center cyclic hydroxylamine antioxidant.

[0004] The purpose of the present invention is to provide a highly active hydroxylamine antioxidant and a preparation method thereof to solve the problem of large addition amount of existing bis(octadecyl)hydroxylamine.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions:

[0006] A highly active hydroxylamine antioxidant, which includes a multi-active center hydroxylamine antioxidant and a single-active center cyclic hydroxylamine antioxidant. Among them, the structure of the multi-active center hydroxylamine antioxidant is where X = Cl, Br, I, m = 0 - 30, n = 1 - 100;

[0007] The structure of the single-active center cyclic hydroxylamine antioxidant is where y = 4 - 30.

[0008] Further, the preparation method of the high-activity hydroxylamine antioxidant comprises the following steps:

[0009] Weigh hydroxylamine hydrochloride, base, haloalkane and solvent in proportion, mix and react for a certain time, then filter, wash with water and dry to obtain the high-activity hydroxylamine antioxidant.

[0010] Further, the base is one or more of sodium hydroxide, potassium hydroxide, pyridine, 1,8-diazabicyclo[5.4.0]undec-7-ene, 4-dimethylaminopyridine, N,N-dimethylethylamine, N,N-diethylmethylamine, N,N-dimethylaniline, triethylamine, triethylenediamine.

[0011] Further, the dosage of the base is 10%-300% of the total mass of hydroxylamine hydrochloride.

[0012] Further, the haloalkane is where X is one of Cl, Br, I, and m = 0-30.

[0013] Or, the haloalkane is where X is one of Cl, Br, I, a = 0-30, and b = 1-6.

[0014] Further, the solvent is one or more of benzene, toluene, xylene, mesitylene, benzotrifluoride, ether, acetonitrile, dichloromethane, dichloroethane, chloroform, ethyl acetate, tetrahydrofuran, 1,4-dioxane, methyldioxane, 1,3-dioxane, propylene oxide.

[0015] Further, the reaction temperature is 10-300 °C.

[0016] Further, the reaction time is 1 s-48 h.

[0017] Application: Application of the high-activity antioxidant in improving the antioxidant effect of polyolefin.

[0018] Advantages of the present invention:

[0019] The present invention provides a multi-active center hydroxylamine antioxidant and a single-active center cyclic hydroxylamine antioxidant and their preparation methods. The production process is simple, the reaction conditions required are mild, and the reaction speed is fast; compared with the single-active center chain-like hydroxylamine antioxidant, the addition amount is less, the decomposition temperature is higher, and the antioxidant effect lasts longer. Description of the drawings

[0020] Figure 1 1H NMR spectrum of antioxidant A obtained in Example 1.

[0021] Figure 2 It is the thermogravimetric spectrum of antioxidant A obtained in Example 1. Detailed implementation manners

[0022] The technical solutions of the present invention will be further described below through examples.

[0023] The terms used in the present invention generally have the meanings commonly understood by those of ordinary skill in the art, unless otherwise specified.

[0024] In the following examples, various processes and methods not described in detail are conventional methods well known in the art. At the same time, since there are many types of alkalis and the structural ratios of haloalkanes are diverse, not all preparation methods are described in detail. Typical examples are taken to illustrate the specific process steps of the present invention.

[0025] Example 1

[0026] Add 2.08 g of hydroxylamine hydrochloride, 25 mL of N,N-dimethyl ethylamine, and 90 mL of tetrahydrofuran into a 500 mL flask. Premix and react at 30 °C for 30 min, then raise the temperature to 60 °C and dropwise add 20 g of 1,18-dibromooctadecane. After the addition is complete, raise the temperature to 85 °C and keep the temperature for reaction for 7 h. After the reaction is completed, cool the reaction solution and perform suction filtration. For the filter cake obtained by suction filtration, perform water washing and drying to obtain 12.5 g of white powdery antioxidant A, with a yield of 66%. After HPLC and 1 1H NMR analysis, the structural formula of the white powdery antioxidant A is: (mass ratio 5%) and (mass ratio 95%), where n is 1-10.

[0027] Example 2

[0028] Add 2.08 g of hydroxylamine hydrochloride, 25 mL of N,N-dimethyl ethylamine, and 90 mL of dichloroethane into a 500 mL flask. Premix and react at 30 °C for 30 min, then raise the temperature to 60 °C and dropwise add 20 g of 1,18-dibromooctadecane. After the addition is complete, raise the temperature to 85 °C and keep the temperature for reaction for 7 h. After the reaction is completed, cool the reaction solution and perform suction filtration. For the filter cake obtained by suction filtration, perform water washing and drying to obtain 11.8 g of white powdery antioxidant A, with a yield of 62%. After HPLC and 1 1H NMR analysis, the structural formula of the white powdery antioxidant A is: (mass ratio 5%) and (mass ratio 95%), where n is 1-10.

[0029] Example 3

[0030] Add 2.08 g of hydroxylamine hydrochloride, 25 mL of N,N-dimethylethylamine, 90 mL of toluene into a 500 mL flask, premix and react at 30 °C for 30 min, then raise the temperature to 60 °C and dropwise add 20 g of 1,18-dibromooctadecane. After the addition is completed, raise the temperature to 85 °C and keep the temperature for reaction for 7 h. After the reaction is completed, cool down the reaction solution and perform suction filtration. For the filter cake obtained by suction filtration, wash it with water and dry it to obtain 13.1 g of white powdery antioxidant A, with a yield of 69%. After HPLC and 1 H NMR analysis, the structural formula of white powdery antioxidant A is: (mass ratio 4%) and (mass ratio 96%), where n is 1-10.

[0031] Example 4

[0032] Add 2.08 g of hydroxylamine hydrochloride, 25 mL of pyridine, 90 mL of mesitylene into a 500 mL flask, premix and react at 30 °C for 30 min, then raise the temperature to 60 °C and dropwise add 20 g of 1,18-dibromooctadecane. After the addition is completed, raise the temperature to 100 °C and keep the temperature for reaction for 7 h. After the reaction is completed, cool down the reaction solution and perform suction filtration. For the filter cake obtained by suction filtration, wash it with water and dry it to obtain 13.6 g of white powdery antioxidant A, with a yield of 72%. After HPLC and 1 H NMR analysis, the structural formula of white powdery antioxidant A is: (mass ratio 3%) and (mass ratio 97%), where n is 1-10.

[0033] Example 5

[0034] Add 2.08 g of hydroxylamine hydrochloride, 17 mL of DBU, 90 mL of ethyl acetate into a 500 mL flask, premix and react at 30 °C for 30 min, then raise the temperature to 60 °C and dropwise add 20 g of 1,18-dibromooctadecane. After the addition is completed, raise the temperature to 85 °C and keep the temperature for reaction for 7 h. After the reaction is completed, cool down the reaction solution and perform suction filtration. For the filter cake obtained by suction filtration, wash it with water and dry it to obtain 11.7 g of white powdery antioxidant A, with a yield of 62%. After HPLC and 1 H NMR analysis, the structural formula of white powdery antioxidant A is: (mass ratio 5%) and (mass ratio 95%), where n is 1-10.

[0035] Example 6

[0036] The reaction steps and operations are the same as those in Example 1. The difference from Example 1 is that the solvent is acetonitrile. Stop the reaction, and after post-treatment, 12.4 g of white powdery antioxidant A is obtained, with a yield of 65%. After HPLC and 1The structural formula of the white powdery antioxidant A analyzed by \(^1H\) NMR is: (mass ratio 5%) and (mass ratio 95%), where n is 1 - 10.

[0037] Example 7

[0038] The reaction steps and operations are the same as those in Example 1. The difference from Example 1 is that the solvent is toluene and the holding reaction temperature is 100 °C. The reaction was stopped, and after post-treatment, 10.9 g of white powdery antioxidant A was obtained with a yield of 57%. Analyzed by HPLC and 1 The structural formula of the white powdery antioxidant A analyzed by \(^1H\) NMR is: (mass ratio 4%) and (mass ratio 96%), where n is 1 - 10.

[0039] Example 8

[0040] The reaction steps and operations are the same as those in Example 1. The difference from Example 1 is that 1,18-dibromooctadecane is changed to 1,20-dibromoeicosane. After post-treatment, 10.9 g of white powdery antioxidant B was obtained with a yield of 57%. Analyzed by HPLC and 1 The structural formula of the white powdery antioxidant B analyzed by \(^1H\) NMR is: (mass ratio 5%) and

[0041]

[0042] (mass ratio 95%), where n is 1 - 10.

[0043] Example 9

[0044] The reaction steps and operations are the same as those in Example 1. The difference from Example 1 is that 1,18-dibromooctadecane is changed to 1,12-dibromododecane. After post-treatment, 5.2 g of white powdery antioxidant F was obtained with a yield of 27%. Analyzed by HPLC and 1 The structural formula of the white powdery antioxidant F analyzed by \(^1H\) NMR is: (mass ratio 37%) and (mass ratio 63%), where n is 1 - 10.

[0045] Example 10

[0046] The reaction steps and operations are the same as those in Example 12. The difference from Example 12 is that the addition amount of 1,12-dibromododecane is changed to 10 g. After post-treatment, 5.2 g of white powdery antioxidant F was obtained with a yield of 57%. Analyzed by HPLC and 1 The structural formula of the white powdery antioxidant F analyzed by \(^1H\) NMR is: (Mass percentage: 100%).

[0047] Application Example 1

[0048] Process of modifying HDPE with antioxidant A

[0049] Mix HDPE (HS5820, Zhonghua Quanzhou Petrochemical), antioxidant A of Example 1, auxiliary antioxidant 168, calcium stearate, zinc stearate, and PPA additive in a mass ratio of 10000:1:1:3:1:2. After the mixture is evenly mixed by a high-speed mixer, it is added into a twin-screw extruder from the main feeding port. The set temperatures of the extruder from the feeding zone to the die head are 60°C, 90°C, 130°C, 180°C, 200°C, 220°C, 220°C, 210°C, 190°C, 180°C, the screw speed is 200 r / min, and modified HDPE pellets are prepared by extrusion granulation.

[0050] Application Example 2

[0051] Process of modifying HDPE with antioxidant B

[0052] Mix HDPE (HS5820, Zhonghua Quanzhou Petrochemical), antioxidant B of Example 8, auxiliary antioxidant 168, calcium stearate, zinc stearate, and PPA additive in a mass ratio of 10000:1:1:3:1:2. After the mixture is evenly mixed by a high-speed mixer, it is added into a twin-screw extruder from the main feeding port. The set temperatures of the extruder from the feeding zone to the die head are 60°C, 90°C, 130°C, 180°C, 200°C, 220°C, 220°C, 210°C, 190°C, 180°C, the screw speed is 200 r / min, and modified HDPE pellets are prepared by extrusion granulation.

[0053] Application Comparative Example 1

[0054] Process of modifying HDPE with bis(octadecyl)hydroxylamine

[0055] Mix HDPE (HS5820, Zhonghua Quanzhou Petrochemical), bis(octadecyl)hydroxylamine, auxiliary antioxidant 168, calcium stearate, zinc stearate, and PPA additive in a mass ratio of 10000:1:1:3:1:2. After the mixture is evenly mixed by a high-speed mixer, it is added into a twin-screw extruder from the main feeding port. The set temperatures of the extruder from the feeding zone to the die head are 60°C, 90°C, 130°C, 180°C, 200°C, 220°C, 220°C, 210°C, 190°C, 180°C, the screw speed is 200 r / min, and modified HDPE pellets are prepared by extrusion granulation.

[0056] The modified HDPE prepared in Application Example 1-2 was repeatedly extruded by a twin-screw extruder for multiple times, and the change in the yellowness index of HDPE after multiple extrusions was measured to test the long-term effectiveness of the antioxidant. The comparison data of bis(octadecyl)hydroxylamine with each application example are listed in the following table.

[0057] sample decomposition temperature Yellowness Index of the first extrusion Yellowness Index of the fourth extrusion bis(octadecyl)hydroxylamine 143℃ -1.54 2.03 Antioxidant A 348℃ -2.57 1.25 Antioxidant B 323℃ -2.96 1.07

[0058] Compared with bis(octadecyl)hydroxylamine, the decomposition temperature of Antioxidants A and B increased significantly, indicating that the stability of Antioxidants A and B was greatly improved. Whether it was the first extrusion or multiple extrusions, the yellowness index of the polyolefin materials with Antioxidants A and B was at a relatively low level, indicating that such hydroxylamine antioxidants had higher activity compared with the traditional bis(octadecyl)hydroxylamine.

[0059] The above are only the preferred embodiments of the present invention, and all equivalent changes and modifications made according to the scope of the patent application of the present invention shall fall within the scope covered by the present invention.

Claims

1. A highly active hydroxylamine antioxidant, characterized in that: The highly active hydroxylamine antioxidants include multi-active center hydroxylamine antioxidants and single-active center cyclic hydroxylamine antioxidants, wherein the multi-active center hydroxylamine antioxidant structure is , where X = Cl, Br, I, m = 0-30, n = 1-100; The structure of the single active center cyclic hydroxylamine antioxidant is , where y = 4-30.

2. The method for preparing a highly active hydroxylamine antioxidant according to claim 1, characterized in that: The following steps are involved: Hydroxylamine hydrochloride, alkali, halogenated alkane and solvent are weighed in proportion, mixed and reacted for a certain period of time, filtered, washed with water and dried to obtain the highly active hydroxylamine antioxidant.

3. The preparation method according to claim 2, characterized in that: The base is one or more of sodium hydroxide, potassium hydroxide, pyridine, 1,8-diazobispiro[5.4.0]undec-7-ene, 4-dimethylaminopyridine, N,N-dimethylethylamine, N,N-diethylmethylamine, N,N-dimethylaniline, triethylamine, and triethylenediamine.

4. The preparation method according to claim 2, characterized in that: The amount of the base used is 10%-300% of the total mass of hydroxylamine hydrochloride.

5. The preparation method according to claim 2, characterized in that: The halogenated alkane is , wherein X = one of Cl, Br, I, and m = 0-30.

6. The preparation method according to claim 2, characterized in that: The halogenated alkane is , wherein X = one of Cl, Br, I, a = 0-30, b = 1-6.

7. The preparation method according to claim 2, characterized in that: The solvent is one or more of benzene, toluene, xylene, trimethylbenzene, trifluorotoluene, ether, acetonitrile, dichloromethane, dichloroethane, chloroform, ethyl acetate, tetrahydrofuran, 1,4-dioxane, methyldioxane, 1,3-dioxane, and propylene oxide.

8. The preparation method according to claim 2, characterized in that: The reaction temperature is 10-300 o C.

9. The preparation method according to claim 2, characterized in that: The reaction time is 1 s-48 h.

10. Application of highly active antioxidants in improving the antioxidant effect of polyolefins.

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