Macromolecular antioxidant, preparation method and application of macromolecular antioxidant in modified engineering plastics

Abstract

The invention discloses a macromolecular antioxidant, which is characterized in that the antioxidant is a binary or ternary copolymer containing 2-((3-(3, 5-di-tert-butyl-4-hydroxyphenyl) propionyl) oxy) acrylic acid ethyl (propyl) ester. The antioxidant is a 2-((3-(3, 5-di-tert-butyl-4-hydroxyphenyl) propionyl) oxy) ethyl acrylate-N-phenylmaleimide binary copolymer (POE) and a 2-((3-(3, 5-di-tert-butyl-4-hydroxyphenyl) propionyl) oxy) propyl acrylate-N-phenylmaleimide binary copolymer (POP), the specific structural formulas are respectively as follows: # imgabs0 #, and n is equal to 10 to 100.

Description

Technical Field

[0001] The invention relates to the preparation of two antioxidants and modified nylon 6 thereof, and specifically belongs to the field of synthesis of resin raw materials and pharmaceutical pesticide intermediates. Background Art

[0002] Nylon 6 is prone to thermal oxidative aging under heat and oxygen conditions. Oxidation is a series of free radical autocatalytic processes that will cause polyamide to degrade. The chain reaction continues, resulting in a decrease in mechanical properties and affecting its service life. In order to delay the thermal oxidative aging of nylon 6 and increase its service life, adding antioxidants to nylon 6 is the most common method to prevent its thermal oxidative aging. Currently, the antioxidants reported in the literature mainly include antioxidant 245, antioxidant 1135, antioxidant 1076, antioxidant 1010, antioxidant 1098, etc. Although these antioxidants have a wide range of applications and show excellent thermal oxidative aging resistance in most polymer materials, there are still some shortcomings, which are mainly manifested in two aspects: first, the antioxidant performance still needs to be improved, and second, the anti-migration performance is poor, and its antioxidant activity cannot be exerted for a long time. With the development of society, PA6 has been widely used in various fields. How to improve the aging resistance of nylon 6 and maintain this performance for a long time has become a difficult problem to be solved by workers in this field. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide 2-((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)oxy)ethyl(propyl)acrylate antioxidant, and copolymerize them with N-phenylmaleimide to obtain two copolymerized antioxidants, so as to solve the problem of poor anti-migration property of antioxidants in the prior art.

[0004] The technical scheme of the present invention is: a type of macromolecular antioxidant, wherein the antioxidant is a functional group-containing 2-((3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionyl)oxy)ethyl (propyl) acrylate, a binary or ternary copolymer.

[0005] The antioxidant is a copolymer of 2-((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)oxy)ethyl (propyl) acrylate and N-phenylmaleimide.

[0006] The antioxidant is a 2-((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)oxy)ethyl acrylate-N-phenylmaleimide copolymer (POE) and a 2-((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)oxy)propyl acrylate-N-phenylmaleimide copolymer (POP), and the specific structural formulas thereof are:

[0007]

[0008] Among them, n=10-100.

[0009] The reaction formula of the POE is as follows:

[0010]

[0011] The preparation method of the antioxidant POE, the reaction steps are as follows:

[0012] (1) heating an oil bath to 50-100° C., adding a cyclohexanone solution of ethyl 2-((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)oxy)acrylate and N-phenylmaleimide to a reactor, stirring at this temperature for 20-60 min, introducing nitrogen, stirring, adding an initiator azobisisobutyronitrile, heating to 90-130° C. for reaction, and reacting for 5-10 h;

[0013] (2) pouring the reaction solution into petroleum ether while hot and stirring to obtain a crude product;

[0014] (3) dissolving the crude product in ethyl acetate and re-precipitating with petroleum ether;

[0015] (4) The obtained product is vacuum dried at 60-100° C. for 12-24 h to obtain a powdery binary copolymer sample, namely, a macromolecular antioxidant POE.

[0016] The reaction formula of the POP is as follows:

[0017]

[0018] The preparation method of the antioxidant POP comprises the following reaction steps:

[0019] (1) heating an oil bath to 50-100° C., adding a cyclohexanone solution of 2-((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)oxy)propyl acrylate and N-phenylmaleimide to a reactor, stirring at this temperature for 20-60 min, introducing nitrogen, stirring, adding an initiator azobisisobutyronitrile, heating to 90-130° C. for reaction, and reacting for 3-5 h;

[0020] (2) pouring the reaction solution into petroleum ether while hot and stirring to obtain a crude product;

[0021] (3) dissolving the crude product in ethyl acetate and re-precipitating with petroleum ether;

[0022] (4) The obtained product is vacuum dried at 60-100° C. for 12-24 h to obtain a powdery binary copolymer sample, i.e., a macromolecular antioxidant POP.

[0023] In the preparation method of the two antioxidants, the molar ratio of 2-((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)oxy)ethyl(propyl)acrylate and N-phenylmaleimide is 1:1-4; the precipitant of the first precipitation is a non-polar solvent, and the second precipitation is a mixture of a non-polar solvent and a polar solvent in a ratio of 1:1-2.

[0024] Beneficial effects of the present invention: The present invention prepares a macromolecular antioxidant copolymerized from 2-((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)oxy)ethyl(propyl)acrylate and N-phenylmaleimide; the two polymers have good resistance to thermal oxidative aging and can be used as thermal oxidative aging inhibitors for engineering plastics such as PA6 and PA56 with good effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The mechanical properties of the product in this application after aging for 12 days;

[0026] Figure 2 The stress-strain curve results of the product in this application after aging for 12 days;

[0027] Figure 3 The stress-strain curve results of the product in this application are (a) aging for 0 days; (b) aging for 4 days;

[0028] Figure 4 This is the nuclear magnetic resonance hydrogen spectrum characterization diagram of the product in this application. DETAILED DESCRIPTION

[0029] The present invention is further described below by means of specific examples, but the examples do not limit the protection scope of the present invention.

[0030] Example 1

[0031] 2-((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)oxy)ethyl acrylate and N-phenylmaleimide are polycondensed to obtain a binary copolymer product, and the preparation method is as follows:

[0032] Heat the oil bath to 75°C, dissolve 13.1677g of ethyl 2-((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)oxy)acrylate and 7.5271g of N-phenylmaleimide in 80mL of cyclohexanone; transfer the solution to a 500ml three-necked flask equipped with a stirrer, a condenser and an air duct, introduce nitrogen, and stir at this temperature for 30min, add 0.4599g of azobisisobutyronitrile, heat to 100°C and react for 5h; slowly pour the reaction solution into 600ml of petroleum ether while hot, stir to obtain a crude product; dissolve the crude product in 20ml of ethyl acetate, and precipitate again with 600ml of petroleum ether to remove the monomer; dry the obtained product in vacuum at 80°C for 24h to obtain a powdery binary copolymer resin sample, i.e., antioxidant POE.

[0033] Example 2

[0034] 2-((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)oxy)propyl acrylate and N-phenylmaleimide are polycondensed to obtain a binary copolymer product, and the preparation method is as follows:

[0035] Heat the oil bath to 75°C, dissolve 13.6584g of 2-((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)oxy)propyl acrylate and 7.5271g of N-phenylmaleimide in 80mL of cyclohexanone; transfer the solution to a 500ml three-necked flask equipped with a stirrer, a condenser and an air duct, introduce nitrogen, and stir at this temperature for 30min, add 0.4599g of azobisisobutyronitrile, heat to 100°C and react for 5h; slowly pour the reaction solution into 700ml of petroleum ether while hot, stir to obtain a crude product; dissolve the crude product in 20ml of ethyl acetate, and precipitate again with 700ml of petroleum ether to remove the monomer; dry the obtained product in vacuum at 80°C for 24h to obtain a powdery binary copolymer resin sample, i.e., antioxidant POP.

[0036] The product obtained in Example 2 was added to nylon 6 (PA6), and the composite material was subjected to a thermal oxidation aging performance study. The results of the tensile strength, elongation at break, and impact strength were shown in the following table after thermal oxidation aging at 150°C for 4 days:

[0037]

[0038]

[0039] Note: No. 1 in the table has no antioxidant added, No. 2 has 1% POE added, and No. 3 has 1% POP added.

[0040] The product obtained in Example 2 was added to nylon 6 (PA6) to obtain PA6 / POE and PA6 / POP composite materials, and the thermal oxidation aging properties of PA6, PA6 / POE and PA6 / POP composite materials were studied. Figure 1 As shown in a, after one day of aging, the tensile strength of PA6 reached a maximum value of 76.25 MPa, and then showed a gradually decreasing trend; PA6 / POE reached a maximum value of 81.77 MPa on the fourth day, and until the 12th day of aging, it still had a tensile strength of 31.85 MPa, and the retention rate was 39% of the initial value; PA6 / POP reached a maximum value of 81.38 MPa on the eighth day, and until the 12th day of aging, it still had a tensile strength of 74.87 MPa, and the retention rate was 92% of the initial value. Both are better than PA6. Figure 1 b shows the notched impact strength of the samples. Compared with PA6 / POE and PA6 / POP, PA6 showed a sharp decline on the first day of aging, sharply dropping to the lowest level, with a retention rate of 28% of the initial level, and basically maintained this level during the subsequent aging process; PA6 / POE dropped to a level similar to that of PA6 after 12 days of aging, with a retention rate of 31% of the initial level, while PA6 / POP was higher than the former two, at 51%. Overall, the notched impact strength of PA6 / POE and PA6 / POP showed a slow downward trend with the extension of aging time, and the antioxidant effect was significantly improved. The stress-strain curves of PA6, PA6 / POE, PA6 / POP, and PA6 / 1010 are shown in Figure 2. Figure 2 As shown in Figure ac, PA6 shows brittle fracture after one day of aging, and the tensile strength increases and then decreases. PA6 / POE and PA6 / POP show brittle fracture only after 8 days of aging. Thermo-oxidative aging at 150°C, the stress-strain curve results are shown in Figure ac. Figure 1 As shown in the figure, on the 0th day of aging, both exhibited ductile fracture, and the strains of PA6 / POE and PA6 / POP were higher than that of PA6. After 4 days of aging, only PA6 / POE and PA6 / POP still maintained high tensile strength and had ductile fracture, while PA6 had ductile fracture and low tensile strength. Therefore, the addition of POE and POP has increased the thermal oxidation aging resistance of PA6 to a certain extent.

Claims

1. A type of macromolecular antioxidant, characterized in that: The antioxidant is a binary or ternary copolymer containing 2-((3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionyl)oxy)ethyl (propyl) acrylate.

2. A macromolecular antioxidant according to claim 1, characterized in that: The antioxidant is a copolymer of 2-((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)oxy)ethyl (propyl) acrylate and N-phenylmaleimide.

3. The macromolecular antioxidant according to claim 1, characterized in that: The antioxidant is a 2-((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)oxy)ethyl acrylate-N-phenylmaleimide copolymer (POE) and a 2-((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)oxy)propyl acrylate-N-phenylmaleimide copolymer (POP), and the specific structural formulas thereof are: Among them, n=10-100.

4. A macromolecular antioxidant according to claim 3, characterized in that: The reaction formula of the POE is as follows:

5. The macromolecular antioxidant according to claim 3, characterized in that: The reaction formula of POE is as follows: The reaction formula of POP is as follows:

6. The macromolecular antioxidant according to claim 4, characterized in that: The preparation method of POE, the reaction steps are as follows: (1) heating an oil bath to 50-100° C., adding a cyclohexanone solution of ethyl 2-((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)oxy)acrylate and N-phenylmaleimide to a reactor, stirring at this temperature for 20-60 min, introducing nitrogen, stirring, adding an initiator azobisisobutyronitrile, heating to 90-130° C. for reaction, and reacting for 5-10 h; (2) pouring the reaction solution into petroleum ether while hot and stirring to obtain a crude product; (3) dissolving the crude product in ethyl acetate and re-precipitating with petroleum ether; (4) The obtained product is vacuum dried at 60-100° C. for 12-24 h to obtain a powdery binary copolymer sample, namely, a macromolecular antioxidant POE.

7. The macromolecular antioxidant according to claim 5, characterized in that: The preparation method of POP comprises the following reaction steps: (1) heating an oil bath pot to 50-100° C., adding a cyclohexanone solution of propyl-((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)oxy)acrylate and N-phenylmaleimide into a reactor, stirring at this temperature for 20-60 min, introducing nitrogen, stirring, adding an initiator azobisisobutyronitrile, heating to 90-130° C. for reaction, and reacting for 5-10 h; (2) pouring the reaction solution into petroleum ether while hot and stirring to obtain a crude product; (3) dissolving the crude product in ethyl acetate and re-precipitating with petroleum ether; (4) The obtained product is vacuum dried at 60-100° C. for 12-24 h to obtain a powdery binary copolymer sample, i.e., a macromolecular antioxidant POP.

8. A macromolecular antioxidant according to claim 6 or 7, characterized in that: The molar ratio of ethyl 2-((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)oxy)acrylate to (N-phenylmaleimide) is 1:1.5-5; the precipitant of the first precipitation is a non-polar solvent, and the second precipitation agent is a mixture of a non-polar solvent and a polar solvent in a ratio of 1:1-2.

Images