Bio-based intramolecular composite antioxidant as well as preparation method and application thereof

Abstract

The invention discloses a bio-based intramolecular composite antioxidant, which has a structure as shown in the following formula I. The bio-based intramolecular composite antioxidant is synthesized by taking bio-based cardanol as a main raw material, firstly halogenating the cardanol to obtain halogenated cardanol, and then performing amination reaction on the halogenated cardanol and 2-furanmethylamine. The antioxidant not only contains phenolic hydroxyl groups which play a role in inactivating peroxy free radicals in hindered phenol antioxidants, but also contains hindered amine which has a function of capturing peroxy free radicals to prevent or inhibit chain reaction and chain growth reaction, not only has good oxidation resistance, but also has the advantages of easily available raw materials, no toxic or side effect and degradability, and can be degraded even if the antioxidant is decomposed in a high-heat environment. Decomposition products are also safe and harmless. And when being applied to polybutylene-1 resin, the polybutylene-1 resin has no influence on human health and environmental safety. Not only is a bio-based raw material adopted, but also a benzene ring is replaced by an aromatic furan ring, so that the dependence on petrochemical resources is reduced, and the method is more environment-friendly.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of polyolefin resins, in particular to a bio-based intramolecular complex antioxidant and a preparation method and application thereof. BACKGROUND

[0002] High isotactic polybutene-1 (PB) is a semi-crystalline polyolefin thermoplastic resin polymerized from butene-1 monomer, which has excellent temperature resistance, durability, chemical stability, plasticity, and is odorless, non-toxic and non-odor, and is one of the most advanced chemical materials in the world. PB pipes have excellent heat creep resistance and can be used for a long time below 95℃, and the maximum use temperature can reach 110℃. During the processing and use of polybutene-1 material, it is inevitable to be affected by light, heat, oxygen and other factors, and aging phenomena such as hardening, tackiness, powdering and discoloration occur, which greatly shortens the service life. In order to enhance the performance of the polymer during processing and use without affecting its performance, antioxidants are usually added to the polymer to inhibit or delay the occurrence of oxidation reaction and improve the overall performance of the product.

[0003] Antioxidants are mainly divided into hindered phenolic and hindered amine primary antioxidants, phosphite and thioester auxiliary antioxidants, and other antioxidants. Because single-function antioxidants cannot meet the performance requirements of high-end polyolefin materials in many aspects, low-cost and comprehensive performance complex antioxidants are often used, which are generally composed of two or more than two kinds of primary and auxiliary antioxidants, and have a synergistic effect, higher antioxidant activity than single antioxidants, and can effectively deal with the gelation of homo- and copolymers during high-temperature processing under oxygen-deficient conditions, meet the performance requirements of high-end polyolefin materials in many aspects, so multifunctional and complex antioxidants have become one of the main trends in the development of antioxidants.

[0004] Bio-based antioxidant raw materials come from renewable biomass, which is quite different from traditional chemical-based additives. Bio-based antioxidants have the characteristics of environmental friendliness, no pollution residues, and recyclability. With the decreasing of petroleum resources and the requirement of social sustainable development, bio-based chemical products are the only way to achieve sustainable development for human beings, which can alleviate the dependence of the antioxidant industry on petrochemical products and the environmental pollution problems caused thereby. Therefore, the research and development of bio-based products have become a leading trend in the field of world scientific and technological innovation.

[0005] At present, the research and development of bio-based antioxidants mainly focuses on the production of single-function antioxidants. For example, in Chinese patent document CN108530485A, cashew phenol is hydrogenated to form meta-pentadecyl phenol, which is reacted with phosphorus trichloride, pentaerythritol and the like to prepare a phosphite antioxidant, which has heat stability, hydrolysis stability and antioxidant 168. The bio-based antioxidant has the following molecular structure:

[0006]

[0007] Bio-based phosphite antioxidants have large relative molecular mass, good heat resistance and stability, and high compatibility with polyolefin carbon chains. However, they have single performance and cannot be used alone, and need to be compounded with hindered phenolic antioxidants and thioester antioxidants to produce effective antioxidant performance. Bio-based phenolic antioxidants are natural antioxidants due to the presence of phenolic hydroxyl groups, but such bio-based antioxidants have the problems of low antioxidant efficiency, poor thermal stability, and easy discoloration, and often cannot be used alone. Compound additives are a blend of various high molecular material chemical additives, aiming to make the high molecular material chemical additives have multifunctionality and enhanced synergistic effect, so as to make the application simple and convenient. For example, Chinese patent document CN117447768A reports a composite antioxidant including vitamin E and 2,6-di-tert-butyl phenol type hindered phenol, wherein the vitamin E is 0.01% to 1% by mass of the high molecular material, and the 2,6-di-tert-butyl phenol type hindered phenol is 0.01% to 2% by mass of the high molecular material. However, the antioxidant effect is weak. In view of this problem, bio-based intramolecular composite antioxidants are synthesized by alkylation, phosphonation, and sulfidation in the prior art. In recent years, with the in-depth study of the mechanism of composite antioxidants, the intramolecular synergistic effect of intramolecular composite antioxidants has become a hot spot in the field of antioxidant development and application. For example, Chinese patent CN107935867A discloses a cardanol-based antioxidant, which is a phenylamine antioxidant in which the action groups of a cardanol-based antioxidant and an amine-based arylamine and / or amine-based arylamine derivative and / or amine-based aromatic heterocycle and / or amine-based aromatic heterocycle derivative are simultaneously introduced into one molecule to form a phenylamine antioxidant, so as to exert the intramolecular synergistic effect. The cardanol-based phenylamine antioxidant has excellent antioxidant performance and good thermal stability. Although cardanol is green and environmentally friendly, aromatic amines and / or aromatic amine derivatives or aromatic heterocycle amines and / or aromatic heterocycle amine derivatives completely rely on petrochemical resources, which is not conducive to carbon emission and increases the pressure on the environment.

[0008] If other substances can be found to replace benzene ring compounds in antioxidants, the pressure caused by the shortage of petrochemical resources can be avoided, carbon emission can be reduced, the pressure on the environment can be relieved, and good development prospects can be achieved. SUMMARY

[0009] In view of this, the present application provides a kind of bio-based intramolecular complex antioxidant and its preparation method and application, which takes bio-based cashew phenol as main raw material, first cashew phenol is halogenated to obtain halogenated cashew phenol, then halogenated cashew phenol and 2-furan methylamine are synthesized into a kind of bio-based phenolic amine intramolecular complex antioxidant by amination reaction.Both contain the phenolic hydroxyl group in hindered phenolic antioxidant to inactivate peroxide radical, and also contain the hindered amine with the function of capturing peroxide radical to prevent or inhibit chain reaction and chain growth reaction, not only good antioxidant performance, and raw material is easy to obtain and has no toxic side effects and can be degraded, even in high heat environment, the decomposition product is safe and harmless.Used in polybutene-1 resin, it has no influence on human health and environmental safety.Not only bio-based raw materials are used, but also furan ring with aromaticity is used to replace benzene ring, which reduces the dependence on petrochemical resources and is more green and environmentally friendly.

[0010] To achieve the above purpose, the present application adopts the following technical solutions:

[0011] A kind of bio-based intramolecular complex antioxidant, has the structure shown in formula I as follows:

[0012]

[0013]

[0014] Wherein, R is C 15 H 31-2n , n=0-3 integer.

[0015] The present application also provides a kind of preparation method for preparing bio-based intramolecular complex antioxidant shown in formula I from cashew phenol, comprising the following steps:

[0016]

[0017] S1: cashew phenol is halogenated to obtain 2,4,6-trihalogenated cashew phenol shown in formula II;

[0018] S2: 2,4,6-trihalogenated cashew phenol shown in formula II and 2-furan methylamine are aminated to obtain bio-based intramolecular complex antioxidant shown in formula I;

[0019] Wherein, X2 is selected from any one of Cl, Br;

[0020] R is defined as described above.

[0021] In an alternative embodiment, in step S1, the cashew phenol is subjected to first halogenation reaction to obtain 2,4-dihalogenated cashew phenol; then subjected to second halogenation reaction to obtain 2,4,6-trihalogenated cashew phenol shown in formula II.

[0022] In an alternative embodiment, in step S1, the halogenating agent is mixed with the organic solvent containing cardanol at -5-5°C to perform a first halogenation reaction, and then heated to 10-30°C to perform a second halogenation reaction. Specifically, the halogenating agent can be added dropwise into the organic solvent containing cardanol, or the organic solvent containing cardanol can be added dropwise into the halogenating agent.

[0023] In an alternative embodiment, the halogenating agent is a halogen element, preferably Br2 or Cl2.

[0024] In an alternative embodiment, the molar ratio of cardanol to the halogen element is 1:3.0-4.0.

[0025] In an alternative embodiment, the first halogenation reaction is performed for 1-2 h, and the second halogenation reaction is performed for 0.5-2 h.

[0026] In an alternative embodiment, the organic solvent is selected from any one of CHCl3, CCl4 and CS2.

[0027] In an alternative embodiment, the dropwise addition of the organic solvent containing cardanol is performed for 30-100 min.

[0028] In an alternative embodiment, in step S2, 2-furfurylamine is added dropwise into the organic solvent containing 2,4,6-trihalogen cardanol and a catalyst to perform an amination reaction, and then the obtained product is subjected to vacuum distillation and column chromatography to obtain the bio-based intramolecularly complex antioxidant of Formula I.

[0029] Preferably, the molar ratio of 2,4,6-trihalogen cardanol of Formula II to 2-furfurylamine is 1:3.0-4.0, and the column chromatography uses an eluent of ethyl acetate and petroleum ether at a volume ratio of about 1:10.

[0030] In an alternative embodiment, the amination reaction is performed at a temperature of 70-120°C for 24-36 h.

[0031] In an alternative embodiment, the dropwise addition of 2-furfurylamine is performed for 30-90 min.

[0032] In an alternative embodiment, the organic solvent is selected from any one of toluene, xylene and p-xylene.

[0033] In an alternative embodiment, the catalyst is a Pd / BINAP catalytic system, which includes a ligand BINAP (1,1'-binaphthalene-2,2'-bis(diphenylphosphine)) and a Pd salt selected from any one of PdCl4, Pd2(dba)3 or Pd(OAc)2.

[0034] In an alternative embodiment, the molar ratio of the Pd salt to 2,4,6-trihalogen cardanol of formula II is 1:3-7.

[0035] In an alternative embodiment, the molar ratio of the Pd salt to the ligand BINAP is 1:1-1.5.

[0036] The application also provides the use of the above-mentioned bio-based intramolecular complex antioxidant or the bio-based intramolecular complex antioxidant prepared by the above-mentioned method for preparing the bio-based intramolecular complex antioxidant from cardanol in the preparation of polybutene-1 resin; preferably, the bio-based intramolecular complex antioxidant is added to polybutene-1 powder, and then extruded and granulated; more preferably, the amount of the bio-based intramolecular complex antioxidant is 0.1%-0.3% based on 100% of the total mass of the polybutene-1 powder.

[0037] Compared with the prior art, the application has at least the following beneficial effects:

[0038] Beneficial effect 1: The bio-based intramolecular complex antioxidant provided by the application not only has a novel structure, but also can solve the problems of poor antioxidant effect and poor stability caused by the single action mechanism of high-end polyolefin antioxidants. The bio-based intramolecular complex antioxidant contains not only phenolic hydroxyl groups in hindered phenol antioxidants that play a role in inactivating peroxide free radicals, but also hindered amine bonds that have the function of capturing peroxide radicals to prevent or inhibit chain reaction and chain growth reaction. The bio-based intramolecular complex antioxidant not only greatly improves its antioxidant performance, but also is biodegradable, i.e., it can be decomposed even in a high-heat environment, and the decomposition products are safe and harmless. When the bio-based intramolecular complex antioxidant is applied to polybutene-1 resin, it has no effect on human health and environmental safety. The problems of non-degradable existing antioxidants, single antioxidant aging effect of bio-based antioxidants, and weak antioxidant capacity are overcome.

[0039] Beneficial effect 2: The preparation method of the bio-based intramolecular complex antioxidant provided by the application is simple and easy to implement. The bio-based cardanol with antioxidant performance is used as a raw material, and the raw material is easy to obtain and has no toxic side effects. The bio-based cardanol is not only abundant and renewable, but also biodegradable, and is safer and healthier than the alkyl phenol antioxidant materials commonly used in the industry. BRIEF DESCRIPTION OF DRAWINGS

[0040] Figure 1 The bio-based intramolecular complex antioxidant prepared in Example 1 of the application is used in the preparation of polybutene-1 resin. 1 HNMR chart. DETAILED DESCRIPTION

[0041] The application will be described in detail below by way of examples. It is necessary to point out here that the following examples are only used to further illustrate the application and cannot be understood as limiting the scope of protection of the application, and those skilled in the art can make some non-essential improvements and adjustments to the application according to the above description of the application.

[0042] If the specific experimental steps or conditions are not specified in the examples, the operations or conditions can be carried out according to the conventional experimental steps described in the literature in the art. If the reagents or instruments used are not specified by the manufacturer, they are all conventional reagent products that can be obtained by purchase.

[0043] For easy comparison, the polybutene-1 resins used in the following examples and comparative examples are all the same, and the process parameters in the granulation stage are basically similar, and the only difference is that the addition amount of the bio-based intramolecular complex antioxidant is different.

[0044] For easy comparison, the bio-based intramolecular complex antioxidant in the following examples is synthesized by the following route.

[0045]

[0046] According to the standard GB19466.6 "Determination of thermal stability of plastic raw materials by oxidation induction period method", the oxidation induction period of polybutene-1 resin can be evaluated by differential scanning calorimetry (DSC).

[0047] Example 1

[0048] The present embodiment provides a bio-based intramolecular complex antioxidant and its application, and the preparation method of the bio-based intramolecular complex antioxidant comprises the following steps:

[0049] Accurately take 60 g of cardanol (0.2 mol) dissolved in 200 ml of CCl4, and at 0°C, drop it into a four-necked flask containing 51.14 g (0.64 mol) of bromine saturated with bromine water, with a stirrer, a dropping funnel (containing a CCl4 solution of cardanol), a thermometer and an air tube, while stirring. The dropping time of the CCl4 solution of cardanol is 60 min. After the dropping is completed, continue to stir for 1 h to obtain the intermediate 2,4-dibromocardiophenol, then continue to warm the system to 20°C and continue to react for 2 h to end the reaction. After removing the CCl4 from the obtained product by reduced pressure distillation, 98.33 g of 2,4,6-tribromocardiophenol is obtained, with a yield of 91.1 wt%.

[0050] A four-necked flask with stirring, thermometer, reflux condenser was charged with 2,4,6-tribromo cardanol 96.6 g (0.18 mol), xylene (200 ml), 11.17 g PdCl4(0.045 mol) and 31.13 g BINAP (0.05 mol), the temperature was raised to 80°C, and 2-furfurylamine 55.94 g (0.58 mol) was added dropwise (30 min dropwise addition was completed), and the reaction was stirred at 80°C for 24 h until the reaction was completed. The organic layer was separated, and the xylene was removed by distillation under reduced pressure. The product was obtained by column chromatography (eluent: ethyl acetate and petroleum ether in a volume ratio of 1:10) to obtain 133.54 g of intramolecular complex antioxidant, with a yield of 89.6 wt%, and the product had a purity of 99.5 wt%. 1 The HNMR spectrum (DMSO-d6, 400 MHz) is shown in Figure 1 The peak corresponding to each hydrogen in the intramolecular complex antioxidant is shown in the structure and Figure 1 The structure is correct as verified by integration.

[0051]

[0052] In the granulation section of the polybutene-1 resin, 0.15% of the above-mentioned bio-based intramolecular complex antioxidant was added to the polybutene-1 powder, which was 100% of the total mass of the polybutene-1 powder, and the polybutene-1 powder was extruded and granulated by a twin-screw extruder at 210°C. The oxidation induction period of the polybutene-1 resin material was then tested, and the test results are shown in Table 1.

[0053] Example 2

[0054] The present embodiment provides a bio-based intramolecular complex antioxidant and its application. The preparation method of the bio-based intramolecular complex antioxidant comprises the following steps:

[0055] Accurately weighed 60 g of cardanol (0.2 mol) was dissolved in 200 ml of CHCl3, and then placed in a dropping funnel. At -5°C, it was added dropwise into a four-necked flask containing 42.6 g (0.6 mol) of saturated chlorine water, which was equipped with a stirrer, a dropping funnel (containing a CCl4 solution of cardanol), a thermometer, and an air tube. After stirring for 2 h, the temperature was raised to 10°C, and the reaction was continued for 1 h. The product was obtained by distillation under reduced pressure to obtain 2,4,6-trichlorocardiol 94.23 g, with a yield of 87.3 wt%.

[0056] Into a four-necked flask with stirring, thermometer, reflux condenser, 2,4,6-trichlorocrotyl phenol 84.98g (0.16mol), toluene (200ml), 45.786g Pd2(dba)3(0.05mol) and 34.22g BINAP (0.055mol) were added in turn, and the temperature was raised to 100°C under stirring, and 2-furanmethanamine 61.73g (0.64mol) was added dropwise (60min dropwise addition was completed), and the reaction was stirred for 36h. After the reaction was completed, the obtained organic layer was separated as the reaction product, and toluene was distilled out under reduced pressure, and then column chromatography (eluent: ethyl acetate and petroleum ether in a volume ratio of 1:10) was used to obtain 121.69g of the intramolecular complex antioxidant, with a yield of 92.7wt%. The structure was correct according to nuclear magnetic resonance identification.

[0057] In the granulation section of the polybutene-1 resin, 0.2% of the above-mentioned bio-based intramolecular complex antioxidant was added to the polybutene-1 powder, with the total mass of the polybutene-1 powder being 100%, and the polybutene-1 powder was extruded and drawn into strands at 210°C by a double-screw extruder and then granulated, and then the oxidation induction period of the polybutene-1 material resin was tested, and the test results are shown in Table 1.

[0058] Example 3

[0059] The present embodiment provides a bio-based intramolecular complex antioxidant and its application. The preparation method of the bio-based intramolecular complex antioxidant comprises the following steps:

[0060] Accurately take 60g of cardanol (0.2mol) and dissolve it in 200ml of CCl4, and at 5°C, drop it into a four-necked flask with a stirrer, a dropping funnel, a thermometer and an air tube containing 55.93g (0.7mol) of bromine in saturated bromine water, and the dropwise addition time of the CCl4 solution of cardanol is 45min. After the dropwise addition is completed, the reaction is continued for 1.5h under stirring, and then the temperature is raised to 20°C, and the reaction is continued for 2h, and then the reaction is completed. The obtained product is distilled under reduced pressure to obtain 95.96g of 2,4,6-tribromocrotyl phenol, with a yield of 88.9wt%.

[0061] Into a four-necked flask with stirring, thermometer, reflux condenser, 2,4,6-tribromocashew phenol 84.98g (0.16mol), xylene (200ml), 5.98g Pd(OAc)2(0.026mol), and 19.91g BINAP (0.032mol) were sequentially placed, and the temperature was raised to 80°C under stirring, and 2-furfurylamine 55.94g (0.58mol) was added dropwise (90min dropwise addition was completed), and the reaction was stirred for 24h. After the reaction was completed, the obtained organic layer was separated as the reaction product, and the xylene was distilled out under reduced pressure, and then column chromatography (eluent was ethyl acetate and petroleum ether in a volume ratio of 1:10) was performed to obtain 117.62g of the intramolecular complex antioxidant, with a yield of 89.6wt%. The structure was correct according to nuclear magnetic resonance.

[0062] In the granulation section of the polybutene-1 resin, 0.25% of the above-mentioned bio-based intramolecular complex antioxidant was added to the polybutene-1 powder, with the total mass of the polybutene-1 powder being 100%, and the polybutene-1 powder was extruded and drawn into strands at 210°C by a double-screw extruder and was granulated, and then the oxidation induction period of the polybutene-1 material resin was tested, and the test results are shown in Table 1.

[0063] Example 4

[0064] The present embodiment provides a bio-based intramolecular complex antioxidant and its application. The preparation method of the bio-based intramolecular complex antioxidant comprises the following steps:

[0065] Synthesis of bio-based intramolecular complex antioxidant: cashew phenol 60g (0.2mol) was accurately weighed and dissolved in 200ml CHCl3, and at -5°C, it was added dropwise into a four-necked flask with a stirrer, dropping funnel, thermometer, and gas tube containing 63.93g (0.8mol) of bromine in saturated bromine water, and the dropwise addition time of the CCl3 solution of cashew phenol was 60min. After the dropwise addition was completed, the reaction was continued for 2h under stirring, and then the temperature was raised to 30°C, and the reaction was continued for 1h, and then the reaction was completed. The obtained product was distilled under reduced pressure to obtain 2,4,6-tribromocashew phenol 94.23g, with a yield of 87.3wt%.

[0066] Into a four-necked flask with stirring, thermometer, reflux condenser, 2,4,6-tribromocashew phenol 84.98g (0.16mol), p-xylene (200ml), 15.33g Pd2(dba)3(0.026mol) and 16.189g BINAP (0.026mol) were sequentially placed, and the temperature was raised to 120°C with stirring, and 2-furfurylamine 54.01g (0.56mol) was added dropwise (30min dropwise addition was completed), and the reaction was stirred for 32h. After the reaction was completed, the obtained organic layer was separated as the reaction product, and the xylene was distilled out under reduced pressure, and then column chromatography (eluent was ethyl acetate and petroleum ether in a volume ratio of 1:10) was used to obtain 114.08g of intramolecular complex antioxidant, with a yield of 86.9wt%. The structure was correct by nuclear magnetic identification.

[0067] In the granulation section of polybutene-1 resin, 0.3% of the above-mentioned bio-based intramolecular complex antioxidant was added to the polybutene-1 powder, with the total mass of the polybutene-1 powder being 100%, and the polybutene-1 powder was extruded and drawn into strands at 210°C by a double-screw extruder and then granulated, and then the oxidation induction period of the polybutene-1 material resin was tested, and the test results are shown in Table 1.

[0068] Example 5

[0069] The present embodiment provides a bio-based intramolecular complex antioxidant and its application. The preparation method of the bio-based intramolecular complex antioxidant comprises the following steps:

[0070] Synthesis of bio-based intramolecular complex antioxidant: 60g of cashew phenol (0.2mol) was accurately weighed and dissolved in 200ml of CHCl3, and at 0°C, it was added dropwise into a four-necked flask with a stirrer, dropping funnel, thermometer and air tube containing 49.55g (0.62mol) of bromine in saturated bromine water, with stirring, the dropwise addition time of the CCl3 solution of cashew phenol was 90min. After the dropwise addition was completed, the reaction was continued for 2h with stirring, and then the temperature was raised to 30°C, and the reaction was continued for 1.5h, and then the reaction was completed. The obtained product was distilled under reduced pressure to obtain 97.47g of 2,4,6-tribromocashew phenol, with a yield of 90.3wt%.

[0071] A four-necked flask with stirring, thermometer, reflux condenser was charged with 2,4,6-tribromo-catechol 96.6 g (0.18 mol), xylene (200 ml), 6.389 g PdCl4(0.026 mol) and 24.28 g BINAP (0.039 mol) in sequence, and stirred to warm up to 100°C, then 2-furfurylamine 61.73 g (0.64 mol) was added dropwise (30 min dropwise addition was completed), and the reaction was stirred for 36 h. After the reaction was completed, the obtained organic layer was separated as the reaction product, and the xylene was distilled out under reduced pressure, and then column chromatography (eluent was ethyl acetate and petroleum ether in a volume ratio of 1:10) was used to obtain the intramolecular complex antioxidant 131.9 g, with a yield of 88.5 wt%. The structure was correct by nuclear magnetic resonance.

[0072] In the polybutene-1 resin pelletizing section, 0.1 wt% of the above-mentioned bio-based intramolecular complex antioxidant was added to the polybutene-1 powder, which was extruded and drawn by a twin-screw extruder at 210°C and then pelletized, with the total mass of the polybutene-1 powder being 100%. Then the oxidation induction period of the polybutene-1 resin material was tested, and the test results are shown in Table 1.

[0073] Comparative Example 1

[0074] The present comparative example provides a preparation method of a polybutene-1 resin, which comprises the following steps:

[0075] In the polybutene-pelletizing section, 0.2 wt% of a complex additive (octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (antioxidant 1076): bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate (hindered amine 770) = 1:1) was added to the polybutene-1 powder, which was extruded and drawn by a twin-screw extruder and then pelletized, with the total mass of the polybutene-1 powder being 100%. Then the oxidation induction period and mechanical properties of the polybutene-1 resin were tested. The test results are shown in Table 1.

[0076] Comparative Example 2

[0077] The present comparative example provides a preparation method of a polybutene-1 resin, which comprises the following steps:

[0078] In the polybutene-pelletizing section, 0.2 wt% of a complex additive (octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (antioxidant 1076): bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate (hindered amine 770) = 1:1) was added to the polybutene-1 powder, which was extruded and drawn by a twin-screw extruder and then pelletized, with the total mass of the polybutene-1 powder being 100%. Then the oxidation induction period and mechanical properties of the polybutene-1 resin were tested. The test results are shown in Table 1.

[0079] Comparative Example 3

[0080] The present comparative example provides a preparation method of polybutene-1 resin, comprising the following steps:

[0081] In the polybutene-1 pelletizing section, 0.2wt% of cardanol: hindered amine 770 = 1:1 was added to the polybutene-1 powder, taking the total mass of the polybutene-1 powder as 100%, and the polybutene-1 powder was extruded and drawn at 210°C and pelletized by a twin-screw extruder. Then the oxidation induction period of the polybutene-1 resin was tested, and the test results are shown in Table 1.

[0082] Table 1 Analysis test results of polybutene-1 resin

[0083] Sample No. Oxidation induction period / min Example 1 138.7 Example 2 141.3 Example 3 143.6 Example 4 148.2 Example 5 133.4 Comparative Example 1 131.2 Comparative Example 2 134.1 Comparative Example 3 99.4

[0084] As can be seen from the data in the above table, the application of the bio-based intramolecular complex antioxidant provided by the present application to the polybutene-1 resin material can effectively improve the oxidation induction period, and the oxidation induction period increases with the increase of the addition amount. Compared with the polybutene-1 resin material pelletized by the auxiliary agent in Comparative Example 1 (antioxidant 1076 and hindered amine 770), Comparative Example 2 (antioxidant 1010) and Comparative Example 3 (cardanol and hindered amine 770), it can be seen that when the addition amount is the same, i.e. 0.2%, the bio-based phenolic amine antioxidant provided by the present application can significantly improve the oxidation induction period of the polybutene-1 resin.

[0085] Of course, the present application can have other various embodiments and modifications, and those skilled in the art can make various corresponding changes and modifications according to the present application without departing from the spirit and essence of the present application. However, these corresponding changes and modifications should all belong to the protection scope of the claims of the present application.

Claims

1. A bio-based intramolecular composite antioxidant, characterized in that, It has the structure shown in Equation I: Formula I Where R is C 15 H 31-2n n is an integer between 0 and 3.

2. A method for preparing a bio-based intramolecular composite antioxidant of cashew phenol according to formula I, characterized in that, Includes the following steps: S1: Cashew nut alcohol undergoes a halogenation reaction to obtain 2,4,6-trihalocashew nut alcohol as shown in Formula II; S2: The 2,4,6-trihalocainol shown in Formula II undergoes an amination reaction with 2-furanmethylamine to obtain the bio-based intramolecular complex antioxidant shown in Formula I; X is selected from either Cl or Br; R is defined as described in claim 1.

3. The preparation method according to claim 2, characterized in that, In step S1, the cashew phenol undergoes a first halogenation reaction to obtain 2,4-dihalocainol; then undergoes a second halogenation reaction to obtain 2,4,6-trihalocainol as shown in Formula II.

4. The preparation method according to claim 3, characterized in that, At -5 to 5°C, the halogenating agent is mixed with an organic solvent containing cashew phenol to carry out the first halogenation reaction, and then the mixture is heated to 10 to 30°C to carry out the second halogenation reaction.

5. The preparation method according to claim 4, characterized in that, The halogenating agent is an elemental halogen, preferably Br2 or Cl2; The molar ratio of cashew phenol to the halogen element is 1:3.0 to 4.0; The first halogenation reaction takes 1 to 2 hours; the second halogenation reaction takes 0.5 to 2 hours. The organic solvent is selected from any one of CHCl3, CCl4 and CS2.

6. The preparation method according to claim 2, characterized in that, In step S2, 2-furanmethylamine is added dropwise to an organic solvent containing 2,4,6-trihalocainol as shown in Formula II and a catalyst to carry out an amination reaction. Preferably, the molar ratio of 2,4,6-trihalocainol as shown in Formula II to the 2-furanmethylamine is 1:3.0 to 4.

0.

7. The preparation method according to claim 6, characterized in that, The amination reaction was carried out at a temperature of 70–120°C for 24–36 hours. The 2-furan methylamine was added over a period of 30–90 minutes. The organic solvent is selected from toluene, xylene, and p-xylene.

8. The preparation method according to claim 6, characterized in that, The catalyst is selected from the Pd / BINAP catalytic system, including the ligand BINAP and a Pd salt, wherein the Pd salt is selected from any one of PdCl4, Pd2(dba)3 or Pd(OAc)2.

9. The preparation method according to claim 8, characterized in that, The molar ratio of the Pd salt to 2,4,6-trihalocainol as shown in Formula II is 1:3 to 7. The molar ratio of the Pd salt to the ligand BINAP is 1:1 to 1.

5.

10. The application of the bio-based intramolecular composite antioxidant of claim 1 or the bio-based intramolecular composite antioxidant prepared by the method of preparing the bio-based intramolecular composite antioxidant of cashew phenol according to any one of claims 2-9 in the preparation of polybutene-1 resin; preferably, the bio-based intramolecular composite antioxidant is added to the polybutene-1 powder and then extruded and granulated; more preferably, the amount of the bio-based intramolecular composite antioxidant is 0.1% to 0.3% based on the total mass of the polybutene-1 powder as 100%.

Images