Phosphite antioxidant based on bio-based lignin phenol and preparation method and application thereof

Abstract

This invention belongs to the field of bio-based polymer material additives, and relates to a bio-based lignin phenol-based phosphite antioxidant, its preparation method, and its application. Using lignin oxidation degradation products from green and renewable biomass resources as raw materials, this invention synthesizes a lignin phenol-based phosphite antioxidant through structural design. This antioxidant can be used to replace traditional phosphite antioxidants like Antioxidant 168 in polymer materials, improving the thermal stability and antioxidant performance of polymer materials and avoiding the dependence on fossil resources caused by traditional antioxidant production. Simultaneously, this invention explores a new path for the high-value utilization of lignin. The structure of the lignin phenol-based phosphite antioxidant is shown in Formula I.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of bio-based polymer material additives, and relates to a bio-based lignin phenol-based phosphite antioxidant as well as a preparation method and application thereof. BACKGROUND

[0002] Most polymer material products are affected by light, high temperature, mechanical processing and other factors during processing, storage and use, and a series of complex and harmful chain scission or crosslinking processes occur in the macromolecular chains of the materials, which causes behaviors such as surface stickiness, discoloration, cracking and embrittlement of the materials, affects the normal use of the materials, and thus shortens the service life of the materials.

[0003] With the rapid development of domestic petroleum chemical industry, a large number of polyolefin device projects have been built and put into production, which has promoted the prosperity of the antioxidant market. Phosphite antioxidants from traditional petroleum chemical products, such as triphenyl phosphite, trimethyl phosphite, and the most demanded antioxidant 168 in the market, have become the mainstream products in this field. In particular, antioxidant 168, due to its wide range of applications, meets the stability requirements of various polymer materials.

[0004] However, with the continuous development of society, people's demand and dependence on chemical products have significantly increased, and the consumption of petroleum chemical products has reached an unprecedented height. Although the use of petroleum resources has brought convenience to industry and daily life, it has also caused serious environmental pollution and overconsumption of resources. At present, about 92% of the global chemical products rely on fossil fuels. With the decreasing of non-renewable resources and in line with the global environmental protection trend, it is urgent to develop a green and renewable phosphite antioxidant that can completely replace traditional phosphite antioxidants. People have turned their attention to renewable biomass resources. Turning to biomass resources not only can alleviate the problem of resource shortage, but also can reduce the negative impact on the environment and promote sustainable development.

[0005] Renewable biomass lignin is a natural aromatic polymer with a three-dimensional network structure in plant bodies, which is formed by the mutual connection of three phenylpropane units through ether bonds and carbon-carbon bonds, and contains rich aromatic ring structures, aliphatic and aromatic hydroxyl groups, and active groups such as quinone groups, mainly existing in the secondary layer of plant cell walls. As a green and renewable resource, lignin has many advantages such as wide source, light weight, high biological efficiency, and wide ecological adaptability. In recent years, researchers have been trying to find suitable renewable raw materials to produce polymers. In particular, the development and application of lignin depolymerization monomer compounds have gained great interest, including vanillyl alcohol, vanillin, guaiacol, eugenol and eugenol depolymerization monomers, which are widely used in the food, beverage, perfume and pharmaceutical industries due to their unique fragrance and excellent antioxidant and antibacterial properties. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide two types of bio-based lignin phenol-based phosphite antioxidants, IA and IB, to address the shortcomings of the prior art.

[0007] The technical problem that this invention also aims to solve is to provide a method for preparing the above two types of bio-based lignin phenol-based phosphite antioxidants IA and IB.

[0008] Furthermore, the technical problem to be solved by the present invention is to provide the application of the above two types of bio-based lignin phenol-based phosphite antioxidants IA and IB in materials.

[0009] Invention Concept: This invention uses lignin oxidation degradation products as starting materials for structural design, synthesizing two types of phosphite antioxidants, IA and IB, based on green and renewable bio-based lignin phenols. This avoids the dependence on and consumption of fossil resources caused by traditional phosphite antioxidant production, as well as the environmental pollution caused by their degradation products. In particular, the introduction of a large number of aromatic rings into the IB-type antioxidant structure, with its strong rigidity and large steric hindrance, further enhances the material's thermal stability and antioxidant properties.

[0010] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0011] This invention discloses a compound as shown in Formula I;

[0012]

[0013] in,

[0014] R3 and R6 are independently selected from -H, -CH3, -CH2-CH3, or -CH2-CH2-CH3;

[0015] R1, R2, R4, and R5 are independently selected from H or -OCH3;

[0016] R is selected from phenyl or R9 is selected from -H, -CH3, -CH2-CH3, or -CH2-CH2-CH3;

[0017] R7 and R8 are independently selected from H or -OCH3;

[0018] R1 and R4 can be connected via -CH(R 10 - Connect them into a loop; where R 10 Selected from H, -CH3, -CH2-CH3, or -CH2-CH2-CH3. In some embodiments, preferably,

[0019] R3 and R6 are independently selected from -CH2-CH2-CH3, and / or

[0020] R9 is selected from -CH2-CH2-CH3, and / or

[0021] R1 and R4 can be connected via -CH(R 10 - Connect them into a loop; where R 10 Selected from H.

[0022] In some embodiments, and more preferably, the compound of formula I is as follows:

[0023]

[0024] in,

[0025] R1, R2, R4, and R5 are independently selected from H or -OCH3;

[0026] R is selected from phenyl or R9 is selected from -H, -CH3, -CH2-CH3 or -CH2-CH2-CH3; preferably, R9 is selected from -CH2-CH2-CH3;

[0027] R7 and R8 are independently selected from H or -OCH3.

[0028] In some embodiments, and more preferably, the compound of formula I is as shown in formula IAi:

[0029]

[0030] in,

[0031] R1, R2, R4, and R5 are independently selected from H or -OCH3;

[0032] R7 and R8 are independently selected from H or -OCH3;

[0033] R9 is selected from -H, -CH3, -CH2-CH3, or -CH2-CH2-CH3; preferably, R9 is selected from -CH2-CH2-CH3. In some embodiments, and more preferably, the compound of formula I is as shown in formula IA-ii:

[0034]

[0035] Among them, R1, R2, R4, and R5 are independently selected from H or -OCH3.

[0036] In some embodiments, and more preferably, the compound of formula I is as follows:

[0037]

[0038] in,

[0039] R2 and R5 are independently selected from H or -OCH3;

[0040] R is selected from phenyl or

[0041] R9 is selected from -H, -CH3, -CH2-CH3 or -CH2-CH2-CH3; preferably, R9 is selected from -CH2-CH2-CH3;

[0042] R7 and R8 are independently selected from H or -OCH3;

[0043] R 10 Selected from H, -CH3, -CH2-CH3 or -CH2-CH2-CH3; preferably, R 10 Selected from H or -CH3, with H being more preferred.

[0044] In some embodiments, and more preferably, the compound of formula I is as shown in formula IBi:

[0045]

[0046] in,

[0047] R2 and R5 are independently selected from H or -OCH3;

[0048] R7 and R8 are independently selected from H or -OCH3;

[0049] R9 is selected from -H, -CH3, -CH2-CH3 or -CH2-CH2-CH3; preferably, R9 is selected from -CH2-CH2-CH3;

[0050] R 10 Selected from H, -CH3, -CH2-CH3 or -CH2-CH2-CH3; preferably, R 10 Selected from H or -CH3, with H being more preferred.

[0051] In some embodiments, and more preferably, the compound of formula I is as shown in formula IB-ii:

[0052]

[0053] in,

[0054] R2 and R5 are independently selected from H or -OCH3;

[0055] R 10 Selected from H, -CH3, -CH2-CH3 or -CH2-CH2-CH3; preferably, R 10Selected from H or -CH3, with H being more preferred.

[0056] In some embodiments, the compound represented by Formula I is tris(4-ethylphenyl) phosphite, tris(4-ethyl-2-methoxyphenyl) phosphite, tris(4-ethyl-2,6-dimethoxyphenyl) phosphite, bis(4-ethylphenyl) phenyl phosphite, bis(4-ethyl-2-methoxyphenyl) phenyl phosphite, bis(4-ethyl-2,6-dimethoxyphenyl) phenyl phosphite, 2,10-diethyl-6-phenyl-12H-dibenzo[d,g][1,3,2]dioxocyanine, 2,10-diethyl-4,8-dimethoxy-12-methyl ...oxocyanine, 2,10-dioxocyanine, 2,10-dioxocyanine, 2,10-dioxocyanine, 2,10-dioxocyanine, [g][1,3,2]dioxocyanine, 2,10-diethyl-4,8-dimethoxy-6-phenyl-12H-dibenzo[d,g][1,3,2]dioxocyanine, 2,10-diethyl-6-(4-ethyl-2-methoxyphenoxy)-4,8-dimethoxy-12H-dibenzo[d,g][1,3,2]dioxocyanine, 2,10-diethyl-4,8-dimethoxy-6-(4-propylphenoxy)-12H-dibenzo[d,g][1,3,2]dioxocyanine, 2,10-diethyl-6-(4-ethyl-2,6-dimethoxyphenoxy)-4,8-dimethoxy 2,10-dimethyl-6-phenyl-12H-dibenzo[d,g][1,3,2]dioxocyanine, tris(2-methoxy-4-methylphenyl)phosphite, tris(2,6-dimethoxy-4-methylphenyl)phosphite, bis(2-methoxy-4-methylphenyl)phenylphosphite, bis(2,6-dimethoxy-4-methylphenyl)phenylphosphite, 2,10-dimethyl-6-phenyl-12H-dibenzo[d,g][1,3,2]dioxocyanine, 4,8-dimethoxy-2,10-dimethyl-6-phenyl-12H-dibenzo[d,g][1,3,2]dioxocyanine, 4,8-dimethoxy-2,10-dioxocyanine ,12-trimethyl-6-phenyl-12H-dibenzo[d,g][1,3,2]dioxocyanine, 4,8-dimethoxy-2,10-dimethyl-6-(p-tolyloxy)-12H-dibenzo[d,g][1,3,2]dioxocyanine, 4,8-dimethoxy-6-(2-methoxy-4-methylphenoxy)-2,10-dimethyl-12H-dibenzo[d,g][1,3,2]dioxocyclooctane or 6-(2,6-dimethoxy-4-methylphenoxy)-4,8-dimethoxy-2,10-dimethyl-12H-dibenzo[d,g][1,3,2]dioxocyanine.

[0057] In some embodiments, preferably, the compound represented by Formula I is any one of the compounds shown in the following structures:

[0058]

[0059] In some embodiments, and more preferably, the compound represented by Formula I is any one of the compounds shown in the following structures:

[0060]

[0061] In some embodiments, and more preferably, the compound represented by Formula I is a compound with the following structure:

[0062]

[0063] Furthermore, this invention discloses a method for preparing the compound represented by Formula I above, selected from one of the following synthetic routes:

[0064] Synthesis Route 1:

[0065] Compound 1 and Compound 2 undergo a first reaction in the presence of a first catalyst to prepare Compound IA;

[0066]

[0067] in,

[0068] R1=R4, R2=R5, R3=R6;

[0069] R3 is selected from -H, -CH3, -CH2-CH3, or -CH2-CH2-CH3;

[0070] R1 and R2 are independently selected from H or -OCH3;

[0071] R' is selected from Cl or phenyl;

[0072] R is selected from phenyl or

[0073] R7=R1, R8=R2, R9=R3;

[0074] or,

[0075] Synthesis Route 2:

[0076] Compounds 3 and 4 undergo a second reaction under the action of a second catalyst to obtain intermediate 5; intermediate 5 and compound 6 continue to undergo a third reaction under the action of a third catalyst to obtain compound IBa;

[0077]

[0078] in,

[0079] R2 = R5, R3 = R6;

[0080] R3 is selected from -H, -CH3, -CH2-CH3, or -CH2-CH2-CH3;

[0081] R2 is selected from H or -OCH3;

[0082] R 10 Selected from H, -CH3, -CH2-CH3 or -CH2-CH2-CH3;

[0083] R” is selected from phenyl;

[0084] R is selected from phenyl;

[0085] or,

[0086] Synthesis Route 3:

[0087]

[0088] in,

[0089] R2 = R5, R3 = R6;

[0090] R3 is selected from -H, -CH3, -CH2-CH3, or -CH2-CH2-CH3;

[0091] R2 is selected from H or -OCH3;

[0092] R 10 Selected from H, -CH3, -CH2-CH3 or -CH2-CH2-CH3;

[0093] R9 is selected from -H, -CH3, -CH2-CH3, or -CH2-CH2-CH3;

[0094] R7 and R8 are independently selected from H or -OCH3;

[0095] R is selected from

[0096] In some embodiments, in synthetic route 1, the first catalyst is any one or a combination of several of triethylamine, pyridine, diisopropylamine, D301 resin, and dodecyl dimethyl tertiary amine, preferably any one or a combination of two of triethylamine and dodecyl dimethyl tertiary amine, more preferably triethylamine; the molar ratio of -OH in compound 1 to -Cl in compound 2 is 1.00:(1.00-1.30), preferably 1.00:1.15; the molar ratio of compound 2 to the first catalyst is 1.0:(2.0-3.5). The preferred ratio is 1.0:(2.3-3.3); the first solvent used in the first reaction is any one or a combination of toluene, xylene, and chloroform, preferably toluene; the mass-to-volume ratio of compound 1 to the first solvent is 1g:(15-30)mL, preferably 1g:20mL; the reaction temperature of the first reaction is 30-90℃, preferably 40-90℃, more preferably 50-90℃; the reaction time of the first reaction is 1-5h; the first reaction is carried out under inert gas protection; the inert gas is preferably nitrogen.

[0097] In some embodiments, in synthetic route 2, the second catalyst is any one or a combination of several of sodium hydroxide, potassium hydroxide, cesium hydroxide, and 1,8-diazabicyclo(5,4,0)-7-undecene, preferably sodium hydroxide; the molar ratio of compound 3 to compound 4 is 2.00:(1.00-1.30), preferably 2.00:(1.15-1.25); the molar ratio of compound 3 to the second catalyst is 1.0:(0.3-0.4); the second catalyst is fed in the form of an aqueous solution, and the mass concentration of the second catalyst in the solution is 30%-35%; the second reaction is carried out at a temperature of 100℃-150℃, preferably 120℃; the second reaction is carried out for a reaction time of 2-5 h, preferably 3 h.

[0098] In some embodiments, in synthetic route 2, the third catalyst is any one or a combination of several of triethylamine, pyridine, diisopropylamine, D301 resin, and dodecyl dimethyl tertiary amine, preferably any one or a combination of two of triethylamine and dodecyl dimethyl tertiary amine, more preferably triethylamine; the molar ratio of intermediate 5 to compound 6 is 1.00:(1.00-1.30), preferably 1.00:1.15; the molar ratio of compound 6 to the third catalyst is 1.0:(2.0-2.5), preferably 1.0:2.3; the second solvent used in the third reaction is any one or a combination of several of toluene, xylene, and chloroform, preferably toluene; the mass-volume ratio of intermediate 5 to the second solvent is 1g:(15-30)mL, preferably 1g:20mL; the reaction temperature of the third reaction is 40℃-80℃, preferably 60℃; the reaction time of the third reaction is 1-4h, preferably 2h.

[0099] Furthermore, the application of the above-mentioned compounds as antioxidants is also within the scope of protection of this invention; preferably, the application is the use of the compounds as antioxidants in the preparation of polymeric materials with thermal stability and / or antioxidant properties; more preferably, the application is the use of the compounds as antioxidants in the preparation of polyolefin materials with thermal stability and / or antioxidant properties; even more preferably, the application is the use of the compounds as antioxidants in the preparation of polypropylene materials with thermal stability and / or antioxidant properties.

[0100] Specifically, using the above-mentioned compound as an antioxidant, the compound is mixed with polymer raw materials and then extruded through a twin-screw extruder to obtain a polymer material with thermal stability and / or antioxidant properties.

[0101] Specifically, the compound accounts for 0.2% to 1.0% of the mass of the polymer raw material, preferably 0.2% to 0.8%, and more preferably 0.4% to 0.8%.

[0102] Beneficial effects:

[0103] (1) This invention uses lignin oxidation degradation products, a source of abundant green and renewable biomass resources, as raw materials. Through structural design, a lignin phenol-based phosphite antioxidant is synthesized. This antioxidant can be used to replace traditional phosphite antioxidants like Antioxidant 168 in polymer materials, avoiding the dependence on fossil resources caused by traditional antioxidant production and promoting sustainable development. At the same time, this invention explores a new path for the high-value utilization of lignin.

[0104] (2) The preparation method of bio-based lignin phenol-based phosphite antioxidant provided by the present invention is simple to operate and has a mature production process, which can bring better economic and environmental benefits.

[0105] (3) The two types of phosphite antioxidants prepared by the method of the present invention have better thermal stability and antioxidant performance than traditional antioxidant 168. Among them, when the same mass ratio is added, the oxidation induction time of the I-A type antioxidant is better than that of traditional antioxidant 168, and the IB type antioxidant is more than 3 times longer.

[0106] (4) The phosphite antioxidant prepared by the present invention can be applied not only to plastics such as polypropylene, polyethylene, polyvinyl chloride, and polystyrene, but also to various rubber materials such as styrene-butadiene, cis-butadiene, and ethylene propylene diene monomer, as well as other types of polymer materials. Attached Figure Description

[0107] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, and the advantages of the present invention in the above and / or other aspects will become clearer.

[0108] Figure 1 The image shows the carbon NMR spectrum of compound I-A-2 prepared in Example 1.

[0109] Figure 2 The 1H NMR spectrum of compound I-A-2 prepared in Example 1 is shown.

[0110] Figure 3 The mass spectrum of compound I-A-2 prepared in Example 1 is shown.

[0111] Figure 4 The image shows the carbon NMR spectrum of compound I-A-5 prepared in Example 2.

[0112] Figure 5 The image shows the 1H NMR spectrum of compound I-A-5 prepared in Example 2.

[0113] Figure 6 The mass spectrum of compound I-A-5 prepared in Example 2 is shown.

[0114] Figure 7 The image shows the carbon NMR spectrum of 6,6'-methylenebis(2-methoxy-4-propylphenol) prepared in Example 3.

[0115] Figure 8 The 1H NMR spectrum of 6,6'-methylenebis(2-methoxy-4-propylphenol) prepared in Example 3.

[0116] Figure 9The mass spectrum of 6,6'-methylenebis(2-methoxy-4-propylphenol) prepared in Example 3 is shown.

[0117] Figure 10 The image shows the carbon NMR spectrum of compound IB-8 prepared in Example 4.

[0118] Figure 11 The image shows the 1H NMR spectrum of compound IB-8 prepared in Example 4.

[0119] Figure 12 The mass spectrum of compound IB-8 prepared in Example 4 is shown. Detailed Implementation

[0120] The present invention can be better understood from the following embodiments. However, those skilled in the art will readily understand that the descriptions in the embodiments are for illustrative purposes only and should not, and will not, limit the invention as detailed in the claims.

[0121] Unless otherwise specified, the experimental methods described in the following examples are conventional methods; unless otherwise specified, the reagents and materials are commercially available.

[0122] The polypropylene raw material (K8303) used in the embodiments of the present invention was provided by China Petroleum & Chemical Corporation, with a weight average molecular weight of approximately 500,000; antioxidant 168 was provided by Guangdong Kangjin Chemical.

[0123] Example 1: Preparation of antioxidant tris(2-methoxy-4-propylphenyl) phosphate (Ⅰ-A-2)

[0124] The reaction route is shown below:

[0125]

[0126] In a reaction flask, 1 g (6 mmol) of lignin depolymerization monomer propyl guaiacol was added, followed by 20 mL of toluene as the reaction solvent, and then 0.77 g (7.59 mmol) of acid-binding agent triethylamine. The mixture was then stirred with a magnetic stirrer until homogeneous. 0.32 g (2.3 mmol) of PCl3 was measured and mixed with a small amount of toluene to obtain a toluene solution containing PCl3. The reaction flask was fixed and a reflux condenser was set up. The air in the reaction flask was removed with nitrogen. The toluene solution containing PCl3 was slowly added dropwise to the reaction solution at 30 °C with continuous stirring. After the addition was complete, the temperature was raised to 60 °C and reacted for 2 h, and then raised to 90 °C and reacted for 3 h. After the reaction was completed and the reaction solution was cooled, the byproduct triethylamine hydrochloride was removed by filtration. The reaction solvent toluene and unreacted triethylamine were removed by rotary evaporation. The compound tris(2-methoxy-4-propylphenyl) phosphate was obtained by column chromatography (ethyl acetate / n-hexane), designated as compound I-A-2, with a yield of 75%.

[0127] The carbon NMR spectrum of compound I-A-2 is shown below. Figure 1 As shown, the proton spectrum is as follows Figure 2 As shown, the mass spectrum is as follows Figure 3 As shown. The NMR and mass spectrometry data of compound I-A-2 are as follows: 1 H NMR(400MHz,Chloroform-d)δ7.20(dd,J=8.0,1.2Hz,3H),6.77(d,J=2.0Hz,3H),6.72(dd,J= 8.1,2.0Hz,3H),3.77(s,9H),2.61–2.55(m,6H),1.67(q,J=7.5Hz,6H),0.98(t,J=7.3Hz,9H); 13 C NMR (101MHz, Chloroform-d) δ150.75,139.44,139.01,122.09,120.49,112.79,55.87,37.89,24.71,13.83; MSI-MS: [M+H] + 527.35.

[0128] Example 2: Preparation of antioxidant bis(2-methoxy-4-propylphenyl)phenylphosphinite (Ⅰ-A-5)

[0129] The reaction route is shown below:

[0130]

[0131] Add 1 g (6 mmol) of lignin depolymerization monomer propyl guaiacol to the reaction flask, then add 20 mL of toluene as the reaction solvent, followed by triethylamine (0.80 g, 7.93 mmol) as the acid-binding agent. Mix thoroughly with magnetic stirring. Measure 0.62 g (3.45 mmol) of phenyl dichloride phosphorus (DCPP) and mix it thoroughly with a small amount of toluene to obtain a toluene solution containing DCPP. Fix the reaction flask and set up a reflux condenser. Remove all air from the reaction flask with nitrogen. Slowly add the toluene solution containing DCPP to the reaction solution at room temperature while stirring continuously. After the addition is complete, raise the temperature to 50 °C and react for 2 h. After the reaction was completed, the reaction solution was cooled and filtered to remove the byproduct triethylamine hydrochloride. The reaction solvent toluene and unreacted triethylamine were removed by rotary evaporation. The crude product was slurried with n-hexane and then filtered with an oil pump to remove the n-hexane. The resulting white solid was freeze-dried to give the compound bis(2-methoxy-4-propylphenyl)phenylphosphine ester, denoted as compound I-A-5, with a yield of 89%.

[0132] The carbon NMR spectrum of compound I-A-5 is as follows: Figure 4 As shown, the proton spectrum is as follows Figure 5 As shown, the mass spectrum is as follows Figure 6 As shown. The NMR and mass spectrometry data of compound I-A-5 are as follows: 1 H NMR (400MHz, DMSO-d6) δ7.86 (tdd, J=6.6, 3.3, 1.8Hz, 2H), 7.56–7.49 (m, 3H), 7.02 (dd, J=8.0, 1.4Hz, 2H), 6.88 (d, J= 2.0Hz,2H),6.68(dd,J=8.1,1.9Hz,2H),3.71(s,6H),2.50(s,4H),1.57(dt,J=8.9,7.3Hz,4H),0.88(t,J=7.3Hz,6H); 13 C NMR (101MHz, DMSO-d6) δ150.78,142.65,139.23,131.10,130.19,128.68,121.34,120.67,113.42,56.12,37.48,24.61,14.09; MSI-MS: [M+H] + :439.27.

[0133] Example 3: Preparation of the bisphenol compound 6,6'-methylenebis(2-methoxy-4-propylphenol)

[0134] The reaction route is shown below:

[0135]

[0136] 1 g (6 mmol) of propyl guaiacol, 0.281 g (3.45 mmol) of 37% formaldehyde solution, and 0.3 mL of 30% NaOH solution were added to pressure-resistant flasks, and the mixtures were placed in an oil bath and reacted at 120 °C for 3 h. After the reaction was completed, the reaction solution was cooled to room temperature, and then an appropriate amount of ethyl acetate was added to the resulting mixture to dissolve it. The mixture was then extracted three times with water. The resulting ethyl acetate solution was dried over anhydrous sodium sulfate, and then the ethyl acetate was removed by rotary evaporation. The crude product was purified by column chromatography (ethyl acetate / n-hexane) on silica gel to give the bisphenol compound 6,6'-methylenebis(2-methoxy-4-propylphenol) in 85% yield.

[0137] The carbon NMR spectrum of 6,6'-methylenebis(2-methoxy-4-propylphenol) is shown below. Figure 7 As shown, the proton NMR spectrum is as follows: Figure 8 As shown, the mass spectrum is as follows Figure 9 As shown. The NMR and mass spectrometry data for 6,6'-methylenebis(2-methoxy-4-propylphenol) are as follows: 1 HNMR(400MHz,DMSO-d6)δ8.22(s,2H),6.61(d,J=2.0Hz,2H),6.40(d,J=2.0Hz,2H),3.76 (d,J=2.4Hz,8H),2.36(dd,J=8.5,6.7Hz,4H),1.65–1.31(m,4H),0.84(t,J=7.3Hz,6H); 13 C NMR (101MHz, DMSO-d6) δ147.51,142.20,132.47,127.55,122.24,110.05,56.17,37.58,29.20,24.83,14.07; MSI-MS: [MH]-:343.3339.

[0138] Example 4: Preparation of antioxidant 4,8-dimethoxy-6-phenyl-2,10-dipropyl-12H-dibenzo[d,g][1,3,2]dioxanthracene (IB-8)

[0139] The reaction route is shown below:

[0140]

[0141] At room temperature, 1 g (2.906 mmol) of 6,6'-methylenebis(2-methoxy-4-propylphenol) and 0.776 g (7.687 mmol) prepared in Example 3 were added to 20 mL of toluene solution and stirred until homogeneous. Then, a toluene solution containing DCPP (0.598 g (3.342 mmol) was slowly added dropwise to the reaction mixture, and the reaction was heated to 60 °C for 2 h. After the reaction, the triethylamine hydrochloride generated in the reaction was removed by filtration through an oil pump, and the reaction solvent toluene and unreacted triethylamine were removed by rotary evaporation. The residue was washed with ethanol and filtered to obtain a white filter cake, which was dried at room temperature for 48 h to obtain a clean product, namely the antioxidant 4,8-dimethoxy-6-phenyl-2,10-dipropyl-12H-dibenzo[d,g][1,3,2]dioxophosphorus anthracene, denoted as compound IB-8, with a yield of 82%.

[0142] The carbon NMR spectrum of compound IB-8 is as follows: Figure 10 As shown, the proton spectrum is as follows Figure 11 As shown, the mass spectrum is as follows Figure 12 As shown. The NMR and mass spectrometry data of compound IB-8 are as follows: 1 H NMR(400MHz,Chloroform-d)δ8.10(td,J=6.2,3.1Hz,2H),7.65–7.50(m,3H),6.80(d,J=1.9Hz,2H),6.71–6.56(m,2H),4.54(dd,J=12 .7,3.7Hz,1H),3.83(s,6H),3.40(d,J=12.7Hz,1H),2.55(tt,J=9.4,4.9Hz,4H),1.65(dp,J=11.4,7.1Hz,4H),0.97(t,J=7.3Hz,6H); 13 C NMR(101MHz,Chloroform-d)δ151.77,140.98,139.48,136.58,130.61,129.78,1 29.65,128.40,121.32,110.80,56.04,38.07,33.56,24.62,13.86; MSI-MS: [M+H] + :451.26.

[0143] Examples 5-7: Preparation of antioxidant / polypropylene (PP) composite materials

[0144] Before processing, the PP masterbatch (polypropylene masterbatch) was placed in a vacuum drying oven at 60°C for dehydration to remove residual moisture. Subsequently, antioxidants I-A-2 (prepared in Example 1), I-A-5 (prepared in Example 2), and IB-8 (prepared in Example 4) were weighed at 0.2% of the total mass fraction of the PP masterbatch and mixed thoroughly with the PP masterbatch in a mixer. Then, the mixed samples with different antioxidants were extruded using a micro twin-screw extruder (Wuhan Ruiming Plastics Machinery Co., Ltd.) at a speed of 50 rpm. The four extrusion temperatures of the micro twin-screw extruder were set to 190°C, 185°C, 185°C, and 180°C, respectively. The extruded antioxidant I-A-2 / PP composite, antioxidant I-A-5 / PP composite, and antioxidant IB-8 / PP composite were then pelletized for later use.

[0145] Examples 8-10: Preparation of antioxidant / polypropylene (PP) composite materials

[0146] Before processing, the PP masterbatch (polypropylene masterbatch) was placed in a vacuum drying oven at 60°C for dehydration to remove residual moisture. Subsequently, antioxidants I-A-2 (prepared in Example 1), I-A-5 (prepared in Example 2), and IB-8 (prepared in Example 4) at a total mass fraction of 0.4% of the PP masterbatch were weighed and mixed thoroughly with the PP masterbatch in a mixer. Then, the mixed samples with different antioxidants were extruded using a micro twin-screw extruder (Wuhan Ruiming Plastics Machinery Co., Ltd.) at a speed of 50 rpm. The four extrusion temperatures of the micro twin-screw extruder were set to 190°C, 185°C, 185°C, and 180°C, respectively. The extruded antioxidant I-A-2 / PP composite, antioxidant I-A-5 / PP composite, and antioxidant IB-8 / PP composite were then pelletized for later use.

[0147] Examples 11-13: Preparation of antioxidant / polypropylene (PP) composites

[0148] Before processing, the PP masterbatch (polypropylene masterbatch) was placed in a vacuum drying oven at 60°C for dehydration to remove residual moisture. Subsequently, antioxidants I-A-2 (prepared in Example 1), I-A-5 (prepared in Example 2), and IB-8 (prepared in Example 4) at a total mass fraction of 0.6% of the PP masterbatch were weighed and mixed thoroughly with the PP masterbatch in a mixer. Then, the mixed samples with different antioxidants were extruded using a micro twin-screw extruder (Wuhan Ruiming Plastics Machinery Co., Ltd.) at a speed of 50 rpm. The four extrusion temperatures of the micro twin-screw extruder were set to 190°C, 185°C, 185°C, and 180°C, respectively. The extruded antioxidant I-A-2 / PP composite, antioxidant I-A-5 / PP composite, and antioxidant IB-8 / PP composite were then pelletized for later use.

[0149] Examples 14-16: Preparation of antioxidant / polypropylene (PP) composites

[0150] Before processing, the PP masterbatch (polypropylene masterbatch) was placed in a vacuum drying oven at 60°C for dehydration to remove residual moisture. Subsequently, antioxidants I-A-2 (prepared in Example 1), I-A-5 (prepared in Example 2), and IB-8 (prepared in Example 4) at a total mass fraction of 0.8% of the PP masterbatch were weighed and mixed thoroughly with the PP masterbatch in a mixer. Then, the mixed samples with different antioxidants were extruded using a micro twin-screw extruder (Wuhan Ruiming Plastics Machinery Co., Ltd.) at a speed of 50 rpm. The four extrusion temperatures of the micro twin-screw extruder were set to 190°C, 185°C, 185°C, and 180°C, respectively. The extruded antioxidant I-A-2 / PP composite, antioxidant I-A-5 / PP composite, and antioxidant IB-8 / PP composite were then pelletized for later use.

[0151] Comparative Example 1: Preparation of blank polypropylene (PP) composite material

[0152] Before processing, the PP masterbatch was placed in a vacuum drying oven at 60°C for dehydration to remove residual moisture. Subsequently, the blank PP masterbatch was mixed and extruded using a micro twin-screw extruder (Wuhan Ruiming Plastics Machinery Co., Ltd.) at a speed of 50 rpm. The four extrusion temperatures of the micro twin-screw extruder were set to 190°C, 185°C, 185°C, and 180°C, respectively. The extruded blank PP composite material was then pelletized for later use.

[0153] Comparative Example 2: Preparation of Antioxidant 168-Polypropylene (PP) Composite Material

[0154] Before processing, the PP masterbatch was placed in a vacuum drying oven at 60°C for dehydration to remove residual moisture. Then, antioxidant 168, at a total mass fraction of 0.2% of the PP masterbatch, was weighed and mixed thoroughly with the PP masterbatch in a mixer. The mixture sample with added antioxidant 168 was then extruded using a micro twin-screw extruder (Wuhan Ruiming Plastics Machinery Co., Ltd.) at a speed of 50 rpm. The four extrusion temperatures of the micro twin-screw extruder were set to 190°C, 185°C, 185°C, and 180°C, respectively. The extruded antioxidant 168 / PP composite was then pelletized for later use.

[0155] Comparative Example 3: Preparation of Antioxidant 168-Polypropylene (PP) Composite Material

[0156] Before processing, the PP masterbatch was placed in a vacuum drying oven at 60°C for dehydration to remove residual moisture. Then, antioxidant 168, at a total mass fraction of 0.4% of the PP masterbatch, was weighed and mixed thoroughly with the PP masterbatch in a mixer. The mixture sample with added antioxidant 168 was then extruded using a micro twin-screw extruder (Wuhan Ruiming Plastics Machinery Co., Ltd.) at a speed of 50 rpm. The four extrusion temperatures of the micro twin-screw extruder were set to 190°C, 185°C, 185°C, and 180°C, respectively. The extruded antioxidant 168 / PP composite material was then pelletized for later use.

[0157] Comparative Example 4: Preparation of Antioxidant 168-Polypropylene (PP) Composite Material

[0158] Before processing, the PP masterbatch was placed in a vacuum drying oven at 60°C for dehydration to remove residual moisture. Then, antioxidant 168, at a total mass fraction of 0.6% of the PP masterbatch, was weighed and mixed thoroughly with the PP masterbatch in a mixer. The mixture sample with added antioxidant 168 was then extruded using a micro twin-screw extruder (Wuhan Ruiming Plastics Machinery Co., Ltd.) at a speed of 50 rpm. The four extrusion temperatures of the micro twin-screw extruder were set to 190°C, 185°C, 185°C, and 180°C, respectively. The extruded antioxidant 168 / PP composite material was then pelletized for later use.

[0159] Comparative Example 5: Preparation of Antioxidant 168-Polypropylene (PP) Composite Material

[0160] Before processing, the PP masterbatch was placed in a vacuum drying oven at 60°C for dehydration to remove residual moisture. Then, antioxidant 168, at a total mass fraction of 0.8% of the PP masterbatch, was weighed and mixed thoroughly with the PP masterbatch in a mixer. The mixture sample with added antioxidant 168 was then extruded using a micro twin-screw extruder (Wuhan Ruiming Plastics Machinery Co., Ltd.) at a speed of 50 rpm. The four extrusion temperatures of the micro twin-screw extruder were set to 190°C, 185°C, 185°C, and 180°C, respectively. The extruded antioxidant 168 / PP composite material was then pelletized for later use.

[0161] Example 17:

[0162] The composite materials obtained in the above embodiments and comparative examples were tested:

[0163] (1) TGA test: Thermogravimetric analysis was performed on PP composites with different antioxidants. The thermogravimetric analysis was conducted using a DZ-TGA300 thermogravimetric analyzer, and the results are shown in the table. The measurements were performed in accordance with the national standard GB / T 27761-2011.

[0164] (2) DSC test: Oxidation induction test was performed on PP composites with different antioxidants. The oxidation induction time (OIT) was measured by a DZ-DSC300 differential scanning calorimeter. The results are shown in the table. The measurement was performed in accordance with the national standard GB / T19466.6-2009.

[0165] Table 1. Thermogravimetric data of antioxidant / PP composite materials in Examples 8-10, Comparative Examples 1 and 3.

[0166]

[0167] Note: T 5％ T 50％ and T max The temperature at which the sample loses 5%, 50%, and at the maximum rate of weight loss during thermogravimetric analysis is indicated.

[0168] Table 2. Oxidation induction time of antioxidant / PP composite materials in Examples 5-16 and Comparative Examples 1-5 (unit: min)

[0169]

[0170]

[0171] The experimental results in Tables 1 and 2 show that the thermal stability of I-A-2 / PP and I-A-5 / PP composites, represented by class I-A antioxidants, is superior to that of traditional antioxidant 168 / PP composites, especially under O2 atmosphere conditions, where the thermal stability of I-A-2 / PP composites is significantly higher. 5％ and T 50％ Compared to traditional antioxidant 168 / PP composites, the T values ​​were increased by 11°C and 5°C respectively, while the T value of I-A-5 / PP composites was... 5％ and T 50％ Compared to the traditional antioxidant 168 / PP composite material, the oxidation induction time was increased by 10℃ and 7℃, respectively. Meanwhile, the oxidation induction time of the I-A-2 / PP and I-A-5 / PP composite materials with different concentrations of antioxidants was significantly improved compared to the traditional antioxidant 168 / PP composite material. Specifically, the composite materials with 0.4wt% antioxidant I-A-2 and I-A-5 showed an improvement of approximately 5 minutes compared to the composite material with 0.4wt% antioxidant 168.

[0172] The IB-8 / PP composite material, represented by IB-type antioxidants, performed best, exhibiting the highest To under N2 atmosphere. 5％ T 50％ and T max Compared to the antioxidant 168 / PP composite, the temperature increases were 48°C, 9°C, and 5°C; under O2 atmosphere, the temperature of the IB-8 / PP composite was [not specified]. 5％ T 50％ and T max Compared to 168 / PP, the OIT (Oxygen Intake) was improved by 17°C, 10°C, and 12°C. The OIT of the composite material with 0.4 wt% antioxidant IB-8 / PP was about 3 times higher than that of the composite material with antioxidant 168 / PP, while the OIT of the composite material with 0.6 wt% antioxidant IB-8 / PP was about 5 times higher than that of the composite material with antioxidant 168 / PP.

[0173] The experimental results above show that the three phosphite antioxidants based on green renewable biomass lignin phenols exhibit superior thermal stability and antioxidant effects compared to traditional phosphite antioxidants when applied to materials.

[0174] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

[0175] This invention provides ideas and methods for the preparation and application of bio-based lignin phenol-based phosphite antioxidants. Many methods and approaches exist for implementing this technical solution; the above description is merely a preferred embodiment of the invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this invention, and these improvements and modifications should also be considered within the scope of protection of this invention. All components not explicitly stated in this embodiment can be implemented using existing technologies.

Claims

1. A compound as shown in Formula I-B-8; 。 2. The method for preparing the compound represented by formula I-B-8 in claim 1, characterized in that, Compounds 3 and 4 undergo a second reaction under the action of a second catalyst to obtain intermediate 5; intermediate 5 and compound 6 continue to undergo a third reaction under the action of a third catalyst to obtain compound IBa; ； in, R2=R5, R3=R6; R3 is selected from -CH2-CH2-CH3; R2 is selected from -OCH3; R 10 Selected from H; R'' is selected from phenyl; R is selected from phenyl.

3. The preparation method according to claim 2, characterized in that, The second catalyst is any one or a combination of several of sodium hydroxide, potassium hydroxide, cesium hydroxide, and 1,8-diazabicyclo(5,4,0)-7-undecene; the molar ratio of compound 3 to compound 4 is 2.00:(1.00~1.30); the molar ratio of compound 3 to the second catalyst is 1.0:(0.3~0.4); the second catalyst is added in the form of an aqueous solution, and the mass concentration of the second catalyst in the solution is 30%~35%; the reaction temperature of the second reaction is 100℃~150℃; the reaction time of the second reaction is 2~5h; The third catalyst is any one or a combination of several of triethylamine, pyridine, diisopropylamine, D301 resin, and dodecyl dimethyl tertiary amine; the molar ratio of intermediate 5 to compound 6 is 1.00:(1.00~1.30); the molar ratio of compound 6 to the third catalyst is 1.0:(2.0~2.5); the second solvent used in the third reaction is any one or a combination of several of toluene, xylene, and chloroform; the mass-volume ratio of intermediate 5 to the second solvent is 1g:(15~30)mL; the reaction temperature of the third reaction is 40℃~80℃; the reaction time of the third reaction is 1~4 h.

4. The preparation method according to claim 2, characterized in that, The second catalyst is sodium hydroxide; the molar ratio of compound 3 to compound 4 is 2.00:(1.15~1.25); the molar ratio of compound 3 to the second catalyst is 1.0:(0.3~0.4); the second catalyst is added in the form of an aqueous solution, and the mass concentration of the second catalyst in the solution is 30%~35%; the second reaction is carried out at a temperature of 120℃; the second reaction is carried out for 3 hours. The third catalyst is triethylamine; the molar ratio of intermediate 5 to compound 6 is 1.00:1.15; the molar ratio of compound 6 to the third catalyst is 1.0:2.3; the second solvent used in the third reaction is toluene; the mass-volume ratio of intermediate 5 to the second solvent is 1g:20mL; the reaction temperature of the third reaction is 60℃; and the reaction time of the third reaction is 2 h.

5. The use of the compound of claim 1 as an antioxidant in the preparation of polyolefin materials with thermal stability and / or antioxidant properties.

6. The application according to claim 5, characterized in that, The application refers to the use of the compound as an antioxidant in the preparation of polypropylene materials with thermal stability and / or antioxidant properties.

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