Cage type polysilsesquioxane containing amido bond and hindered phenol functional group as well as preparation method and application of cage type polysilsesquioxane

Abstract

The invention discloses polyhedral oligomeric silsesquioxane containing an amido bond and a hindered phenol functional group as well as a preparation method and application of the polyhedral oligomeric silsesquioxane. The structural formula of the polyhedral oligomeric silsesquioxane is one or more of the following formulas I-III, r1 and R2 are independently selected from at least one of hydrogen, alkyl, alkoxy, hydroxyalkyl, cycloalkyl, cycloalkyl alkyl, aryl, aralkyl, heterocyclic radical, heterocyclic radical alkyl, carboxyl, ester group, acylamino, amino, amido, halogen, nitro, cyano, oxycarbonyl and aminocarbonyl; and R3 and R4 are independently selected from alkylene with 0 to 20 carbons. The polyhedral oligomeric silsesquioxane containing the amido bond and the hindered phenol functional group prepared by the preparation method disclosed by the invention is high in hindered phenol functional group content and small in size, long-term and efficient protection can be realized under a low addition amount, and the thermo-oxidative aging resistance of a polymer is effectively improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of polysilsesquioxane, and particularly relates to a cage polysilsesquioxane containing an amide bond and a hindered phenol functional group, a preparation method and application thereof. BACKGROUND

[0002] Cage polysilsesquioxane is a kind of nano-sized synthetic silicon-based compound with clear structure. Each cage polysilsesquioxane molecule has an inorganic silicon-oxygen-silicon core and many organic substituent arms, which bring it rich modification possibilities. In the past two decades, cage polysilsesquioxane compounds have been widely studied in polymer nanocomposites due to their inherent thermal stability and chemical stability, organic-inorganic hybrid structure and designability.

[0003] With the widening of the application field of polymer materials, modified plastics and engineering plastics play an increasingly important role in the automotive industry, liquefied petroleum gas transportation field, electronic industry and aviation field. However, in the face of the increasingly harsh use environment of polymer materials, the performance of the antioxidants on the market cannot meet the further development of polymer materials. Most of the antioxidants on the market currently have the problems of low molecular weight, weak thermal stability and poor extract resistance, which leads to their easy volatilization or migration loss from the polymer matrix, and loss of use efficiency. The research and development of new extract-resistant antioxidants on the domestic market still faces many difficulties and progresses slowly.

[0004] The current trend in the development of antioxidants resistant to extraction is to graft small molecular weight antioxidants onto macromolecular chains or inorganic nanoparticles. There have been reports of antioxidants containing active groups and ultraviolet absorbers being grafted onto high molecular chains through chemical reactions (for example, US Patent US6936659B2; Japanese Patent JP2008260929A) to improve their resistance to extraction. However, there are few types of reactive polymers that have good compatibility with the matrix and can be used to graft antioxidants, and the effective antioxidant immobilization capacity of the polymers after grafting is generally low, so their application is not widespread. In addition, there have also been reports of hindered phenolic antioxidants being grafted onto the surface of nano-silicon dioxide through silane coupling agents (for example, Chinese Patents CN111040471B and CN102206432B) to reduce the loss of antioxidants. However, the size of the inorganic carrier nano-silicon dioxide particles is large, the structure is not clear, and there are few sites available for grafting, resulting in a low grafting rate of hindered phenolic antioxidants, and the anti-aging protection effect of the inorganic particle immobilized hindered phenolic antioxidants on polymers is not obvious enough. However, there are documents published (A. Niemczyk et al. Polymer Degradation and Stability 161 (2019) 30-38) that octa({n-octyl}dimethylsilyloxy)octasilsesquioxane (POSS8) and octa({n-octadecyl}dimethylsilyloxy)octasilsesquioxane (POSS18) can be used as ultraviolet light stabilizers and / or antioxidants for polypropylene (PP). This is due to the good compatibility between the alkyl-modified POSS and PP, the uniform dispersion of the modified POSS, which can fill the free volume of the material, limit the diffusion of oxygen, and possibly inhibit the formation of oxidation products such as ketones and carboxylic acids, thereby improving the aging resistance of PP. However, the antioxidant performance of the alkyl-grafted cage-type polysilsesquioxane obtained by this technology needs to be improved.

[0005] Hindered phenolic compounds are a kind of primary antioxidant often used in polymers, such as and etc. Their anti-aging effect on polymer materials is related to their own chemical structure, molecular weight size, and physical and chemical properties, and the compatibility of the antioxidant with the polymer matrix is also an important factor. For example (N,N'-bis-(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)hexanediamine) is an antioxidant containing amide bonds and hindered phenolic functional groups with a molecular weight of 636.9, which is commonly used in polyamide, polyolefin, polystyrene, ABS resin, acetal resin, polyurethane, and rubber materials, and The amide bond contained can form hydrogen bond with N, O element-containing material such as polyamide to increase the compatibility with the matrix and improve the extraction resistance in the matrix to some extent, and thus it is the most widely used hindered phenolic antioxidant in polyamide materials. However, due to the low molecular weight of the solvent extraction resistance is poor, and in some harsh application conditions, the service life of the polymer is affected due to the physical loss of the hindered phenolic antioxidant.

[0006] Therefore, it is necessary to provide an antioxidant with good compatibility with the polymer matrix, which can effectively inhibit the aging of the polymer and has strong solvent extraction resistance.

[0007] In view of this, the present application is proposed. SUMMARY

[0008] The main purpose of the present application is to provide a cage-shaped poly silesquioxane containing amide bond and hindered phenol functional group and its preparation method and application, so as to overcome the problem that the hindered phenolic antioxidant used as an antioxidant is easy to diffuse and migrate from the polymer to the outside and lose the use effect. The cage-shaped poly silesquioxane containing amide bond and hindered phenol functional group is a new type of antioxidant which is stable in structure, long in time, efficient and environmentally friendly at low addition amount.

[0009] To solve the above technical problems, the basic idea of the technical scheme of the present application is:

[0010] The present application provides a cage-shaped poly silesquioxane containing amide bond and hindered phenol functional group, and the structural formula is one or several of the following structural formula I-III:

[0011]

[0012]

[0013] Among them, R1 and R2 are independently selected from at least one of hydrogen, alkyl, alkoxy, hydroxyalkyl, cycloalkyl, cycloalkylalkyl, aryl, aralkyl, heterocyclic group, heterocyclic group alkyl, carboxyl, ester group, amide group, amino group, amine group, halogen, nitro group, cyano group, oxycarbonyl group, aminocarbonyl group;

[0014] R3 and R4 are independently selected from alkylene group with 0-20 carbons.

[0015] In a further scheme, R1 and R2 each have 0-18 carbons, and R3 and R4 each have 0-6 carbons.

[0016] Preferably, at least one of R1 and R2 is a branched alkyl group with 3-8 carbons.

[0017] In further embodiments, R1 is H or methyl, R2 is a C3-C8 branched alkyl group; and / or, R3 is -CH2-CH2-, R4 is -CH2-CH2-CH2-.

[0018] The present application provides a method for preparing a cage polysilsesquioxane containing an amide bond and a hindered phenol functional group, comprising:

[0019] Step 1, condensation reaction of a cage polysilsesquioxane containing a nitrogen atom and a hindered phenol compound containing a carboxyl group in the presence of a condensation reagent and a base to obtain a reaction mixture;

[0020] Alternatively, the hindered phenol compound containing a carboxyl group is first synthesized into an acid chloride compound by an acid chloride reagent, and then acylation reaction occurs with the cage polysilsesquioxane containing a nitrogen atom in the presence of a base to obtain a reaction mixture;

[0021] Step 2, post-treatment of the reaction mixture to obtain a cage polysilsesquioxane containing an amide bond and a hindered phenol functional group;

[0022] wherein the cage polysilsesquioxane containing a nitrogen atom has a structural formula selected from one or more of the following structural formulas IV-VI, and the structure of the hindered phenol compound containing a carboxyl group is as shown in formula VII:

[0023]

[0024] R1 and R2 are independently selected from at least one of hydrogen, alkyl, alkoxy, hydroxyalkyl, cycloalkyl, cycloalkylalkyl, aryl, aralkyl, heterocyclyl, heterocyclylalkyl, carboxyl, ester, amide, amino, amine, halogen, nitro, cyano, oxycarbonyl, aminocarbonyl;

[0025] R3 and R4 are independently selected from an alkylene group having 0-20 carbons;

[0026] X is selected from amino -NH2 or ammonium -NH3 + .

[0027] In further embodiments, the cage polysilsesquioxane containing a nitrogen atom, the hindered phenol compound containing a carboxyl group, and a solvent are mixed, a condensation reagent and a base are added, and the reaction is carried out. Alternatively, the hindered phenol compound containing a carboxyl group is first synthesized into an acid chloride compound by an acid chloride reagent, and then the cage polysilsesquioxane containing a nitrogen atom is mixed with a solvent, and the reaction is carried out in the presence of a base. The solvent is selected from one or more of the following commonly used solvents: N'N-dimethylformamide, dichloromethane, water, acetonitrile, tetrahydrofuran, acetone, ethanol, ethyl acetate, toluene, dimethyl sulfoxide, etc.

[0028] In a further aspect, in step 1, the condensation reagent is selected from one or more of N,N'-carbonyldiimidazole (CDI), dicyclohexylcarbodiimide (DCC), diisopropylcarbodiimide (DIC), 2-(7-azabenzotriazolyl)-N,N,N',N'-tetramethyluronium hexafluorophosphate (HATU), 0-(1H-benzotriazol-1-yl)-N,N,N',N'-tetramethylisouronium hexafluorophosphate (HBTU), 1-propylphosphonic anhydride (T3P), 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDCI), 1-hydroxybenzotriazole (HOBT), N-hydroxy-7-azabenzotriazole (HOAT), and dimethylaminopyridine (DMAP).

[0029] In a further aspect, in step 1, the acyl chloride reagent is selected from one of phosphorus oxychloride, phosphorus pentachloride, oxalyl chloride, and dichlorosulfoxide.

[0030] In a further aspect, in the process of synthesizing the acyl chloride compound from the carboxyl-containing hindered phenolic compound by the acyl chloride reagent, no solvent is used, or a solvent is used, and the solvent is selected from one of dichloromethane, diethyl ether, carbon tetrachloride, and toluene.

[0031] In a further aspect, in step 1, the base is selected from at least one of triethylamine, N,N-diisopropylethylamine, pyridine, 1,8-diazabicycloundec-7-ene, triethylenediamine, sodium carbonate, potassium carbonate, sodium bicarbonate, sodium hydroxide, and potassium hydroxide.

[0032] In a further aspect, in step 1, the molar ratio of the cage polysilsesquioxane containing nitrogen atoms, the carboxyl-containing hindered phenolic compound, the condensation reagent or the acyl chloride reagent, and the base is 1:(8-36):(8-50):(8-50).

[0033] In a further aspect, in step 1, the condensation reaction or the acylation reaction is performed at a temperature of 0-120℃ for 1-72 hours.

[0034] Preferably, the reaction is performed at a temperature of 25-80℃ for 12-24 hours.

[0035] The application also provides a use of the cage polysilsesquioxane containing a hindered phenolic functional group as described above as an antioxidant for a polymer material.

[0036] The cage polysilsesquioxane containing an amide bond and a hindered phenolic functional group provided by the application can be used as a polymer antioxidant, can effectively inhibit aging of the polymer, and has strong solvent extraction resistance.

[0037] Compared with the prior art, the present application has the following beneficial effects.

[0038] The present application provides a cage polysilsesquioxane containing an amide bond and a hindered phenol functional group, which has a hindered phenol functional group connected through an amide bond on the organic substituent arm, forming a high molecular weight antioxidant with relatively large molecular weight and stable structure, solving the problem of easy migration and loss of small molecular weight hindered phenol compounds, and effectively improving the thermal-oxidative aging resistance of polymers. BRIEF DESCRIPTION OF DRAWINGS

[0039] The accompanying drawings, which are part of the present application, serve to further understand the present application, and the schematic embodiments of the present application and their descriptions are used to explain the present application, but do not constitute an improper limitation on the present application. Obviously, the accompanying drawings described below are only some embodiments, and other drawings can be obtained by those skilled in the art without creative labor. In the drawings:

[0040] Figure 1 Matrix-assisted laser desorption / ionization time-of-flight mass spectrum of the product of Example 4;

[0041] Figure 2 Matrix-assisted laser desorption / ionization time-of-flight mass spectrum of the product of Example 5.

[0042] It should be noted that these drawings and written descriptions are not intended to limit the scope of the concept of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments will be described clearly and completely below with reference to the drawings in the embodiments of the present application. The following embodiments are used to illustrate the present application, but not to limit the scope of the present application.

[0044] The present application provides a cage polysilsesquioxane containing a hindered phenol functional group, which has one or more of the following structures of formula I-III:

[0045]

[0046]

[0047] R1and R2are independently selected from at least one of hydrogen, alkyl, alkoxy, hydroxyalkyl, cycloalkyl, cycloalkylalkyl, aryl, aralkyl, heterocyclyl, heterocyclylalkyl, carboxyl, ester, amide, amino, amine, halogen, nitro, cyano, oxycarbonyl, aminocarbonyl;

[0048] R3and R4are independently selected from alkylene having 0-20 carbons.

[0049] The cage polysilsesquioxane containing amide bond and hindered phenol functional group of the present application can be used as an antioxidant in the polymerization, granulation, storage, processing, molding and use of high molecular materials such as polymer materials. Further, the above polymer material is plastic, for example, polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polystyrene (PS), acrylonitrile-butadiene-styrene copolymer (ABS), polymethyl acrylate PMMA, ethylene-vinyl acetate copolymer PVA, polyamide (PA), polytetrafluoroethylene (TFE) and the like.

[0050] In conventional hindered phenol antioxidant supported by inorganic carrier, the inorganic carrier has large size and unclear structure, and generally has problems such as low grafting rate and insufficient protection effect. Unlike the conventional inorganic support, the cage polysilsesquioxane used in the present application has a clear chemical structure, and has a smaller size, with a Si-O-Si cage skeleton size of several nanometers in diameter; and has more abundant modifiable functional groups, which can achieve a higher grafting amount. The cage polysilsesquioxane containing amide bond and hindered phenol functional group prepared by the present application has a high content of hindered phenol functional groups and a small size, and can achieve long-time and high-efficiency protection at a low addition amount, thereby effectively improving the thermal-oxidative aging resistance of the polymer.

[0051] R1and R2are the same or different, in an embodiment, R1and R2each have 0-18 carbons; in another embodiment, R1and R2are independently selected from C1-C 18 alkyl.

[0052] In an embodiment, at least one of R1and R2is C3-C8 branched alkyl, for example, isopropyl, tert-butyl, tert-pentyl, tert-hexyl, tert-octyl. In another embodiment, R1is H or methyl, and R2is C3-C8 branched alkyl. In yet another embodiment, R1and R2are independently selected from C3-C8 branched alkyl; for example, R1and R2are both tert-butyl, and the cage polysilsesquioxane containing hindered phenol functional group of the present application has the following structure:

[0053]

[0054]

[0055] In one embodiment, R3and R4of the present application each have 0-6 carbons, i.e., R3and R4are independently selected from C0-C6alkylene groups. When R3or R4has 0 carbons, it indicates that R3or R4is absent, the carbonyl group is directly attached to the phenyl group or the silicon is directly attached to the oxygen. In another embodiment, R3is a C2alkylene group, -CH2-CH2-, and R4is a C3alkylene group, -CH2-CH2-CH2-. In yet another embodiment, R3is C0, i.e., the carbonyl group is directly attached to the phenyl group, and R4is a C3alkylene group, -CH2-CH2-CH2-.

[0056] When R1and R2are each t-butyl, R3is C0, i.e., the carbonyl group is directly attached to the phenyl group, and R4is a C3alkylene group, -CH2-CH2-CH2-, the cage polysilsesquioxane of the present application having hindered phenol functionality has the following structure:

[0057]

[0058] When R1and R2are each t-butyl, R3is a C2alkylene group, -CH2-CH2-, and R4is a C3alkylene group, -CH2-CH2-CH2-, the cage polysilsesquioxane of the present application having hindered phenol functionality has the following structure:

[0059]

[0060] The present application also provides a method for preparing the cage polysilsesquioxane of the present application having hindered phenol functionality, comprising the following steps:

[0061] Step 1, condensation reaction of the cage polysilsesquioxane having nitrogen atom with the hindered phenol compound (VII) having carboxyl group in the presence of condensation reagent and base.

[0062] or the hindered phenol compound (VII) having carboxyl group is first reacted with acyl chloride reagent to synthesize acyl chloride compound, and then acylation reaction occurs with the cage polysilsesquioxane having nitrogen atom in the presence of base.

[0063] Step 2, post-treatment of the reaction mixture to obtain the cage polysilsesquioxane having amide bond and hindered phenol functionality;

[0064] wherein the cage polysilsesquioxane having nitrogen atom has one or more of the following structures of Formula IV-VI, and the hindered phenol compound (VII) having carboxyl group has the following structure of Formula VII:

[0065]

[0066]

[0067] R1and R2are independently selected from one or more of hydrogen, alkyl, alkoxy, hydroxyalkyl, cycloalkyl, cycloalkylalkyl, aryl, aralkyl, heterocyclyl, heterocyclylalkyl, carboxyl, ester, amide, amino, amine, halogen, nitro, cyano, oxycarbonyl, aminocarbonyl;

[0068] R3and R4are independently selected from alkylene having 0-20 carbons;

[0069] X is selected from amino -NH2or ammonium -NH3 + .

[0070] In one embodiment, the cage polysilsesquioxane containing nitrogen atom, the hindered phenol compound containing carboxyl group and solvent are mixed, a condensation reagent and a base are added, and a reaction is performed. After the reaction, the mixture is subjected to a post-treatment to obtain the cage polysilsesquioxane containing an amide bond and a hindered phenol functional group, i.e., the compound represented by the structures of Formulae I to III. In another embodiment, the hindered phenol compound containing carboxyl group is first subjected to an acyl chloride reagent to synthesize an acyl chloride compound, and then the cage polysilsesquioxane containing nitrogen atom is mixed with a solvent in the presence of a base, and a reaction is performed.

[0071] In one embodiment, the solvent is selected from one or more of N'N-dimethylformamide, dichloromethane, water, acetonitrile, tetrahydrofuran, acetone, ethanol, ethyl acetate, toluene, dimethyl sulfoxide, and the like. In the mixed solution of the cage polysilsesquioxane containing nitrogen atom, the hindered phenol compound containing carboxyl group and the solvent, the cage polysilsesquioxane containing nitrogen atom has a molar concentration of 0.01 to 1.0 mol / L, preferably 0.02 to 0.2 mol / L in the solvent.

[0072] In one embodiment, the condensation reagent is selected from one or more of N,N'-carbonyldiimidazole (CDI), dicyclohexylcarbodiimide (DCC), diisopropylcarbodiimide (DIC), 2-(7-azabenzotriazolyl)-N,N,N',N'-tetramethyluronium hexafluorophosphate (HATU), 0-(IH-benzotriazol-1-yl)-N,N,N',N'-tetramethylisouronium hexafluorophosphate (HBTU), 1-propylphosphonic anhydride (T3P), 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDCI), 1-hydroxybenzotriazole (HOBT), N-hydroxy-7-azabenzotriazole (HOAT), dimethylaminopyridine (DMAP).

[0073] In one embodiment, in the process of preparing the acyl chloride compound from the hindered phenol compound containing carboxyl group (VII), the acyl chloride reagent is selected from one of phosphorus oxychloride, phosphorus pentachloride, oxalyl chloride, and dichlorosulfoxide; no solvent is used, or one of dichloromethane, diethyl ether, carbon tetrachloride, and toluene is used.

[0074] In one embodiment, the base used in the reaction is selected from one or more of triethylamine, N,N-diisopropylethylamine, pyridine, 1,8-diazabicycloundec-7-ene, triethylenediamine, sodium carbonate, potassium carbonate, sodium bicarbonate, sodium hydroxide, and potassium hydroxide.

[0075] In one embodiment, the molar ratio of the nitrogen-containing cage-type polysilsesquioxane to the carboxyl-containing hindered phenolic compound, condensing agent or acyl chloride agent, and base is (1:8:8:8) to (1:36:50:50).

[0076] In one embodiment, the reaction temperature for the condensation or acylation reaction of the present invention is 0℃-120℃, and the reaction time is 1~72h, preferably 12~24h at 25-80℃.

[0077] In one embodiment, the post-treatment includes cooling the reaction system to room temperature, adding it to an aqueous solution to precipitate the product, centrifuging, filtering, washing, rotary evaporating, and drying to obtain the product. The crude product can be washed with a solvent to dissolve byproducts, and then filtered to obtain the final product. Drying can be performed under vacuum at a temperature of 20-50°C and a vacuum level of -0.1 to -0.05 MPa.

[0078] In one specific embodiment, the post-processing includes: after cooling the reaction system to room temperature, pouring the reaction system into deionized water to precipitate the solid, filtering to obtain the solid, washing with deionized water, washing the obtained crude solid product with a mixed solution of ethyl acetate / n-hexane, filtering to obtain the solid product, drying in a vacuum oven at 50°C for 24 hours to obtain the target product, a cage-like polysilsesquioxane containing amide bonds and hindered phenolic functional groups.

[0079] This invention utilizes the smaller size (a few nanometers) of cage-like polysilsesquioxanes (POSS), their richer modifiable functional groups, and their suitable substituent structures for customized applications. Through a low-energy, simple, and high-yield chemical reaction, a cage-like polysilsesquioxane containing amide bonds and hindered phenolic functional groups is prepared. As a novel antioxidant that achieves long-lasting and highly effective protection at low addition levels, it effectively improves the polymer's resistance to thermo-oxidative aging. Furthermore, it exhibits good dispersion in polymers, minimal leakage, high stability, and strong resistance to extraction.

[0080] The "low addition amount" mentioned in this invention is mainly in contrast to "extraction-resistant antioxidants" that involve "grafting small molecular weight antioxidants onto macromolecular chains or inorganic nanoparticles." The control group antioxidant 1098 in the experimental example is a conventional commercial antioxidant that can achieve an effective concentration at low addition amounts, but its poor extraction resistance leads to rapid loss during use. In contrast, the cage-like polysilsesquioxane containing amide bonds and hindered phenolic functional groups provided by this invention is a novel type of organic-inorganic hybrid nano-antioxidant that still exhibits strong extraction resistance, is not easily lost, and has high stability even at low addition amounts.

[0081] The technical solution of the present invention will be further described in detail below through specific embodiments.

[0082] Main raw material sources:

[0083] Nitrogen-containing cage-like polysilsesquioxane, selected from formula (IV), where X is selected from -NH3. + The synthesis steps are as follows: 14.8 g of 3-aminopropyltrimethoxysilane (80 mmol) was added to 320 mL of an aqueous solution of trifluoromethanesulfonic acid (0.5 mol / L) at room temperature and stirred for 2 h. Then, the mixture was heated to 50 °C in an open container until the solvent was completely evaporated. The crude product was then heated to 100 °C for 2 h and cooled to room temperature. After washing, the product was washed with a mixture of acetone / ethanol (1:1, v / v). The precipitate was separated by filtration and dried in a forced-air drying oven at 70 °C for 5 h to obtain 20.19 g of the target product, nitrogen-containing cage-like polysilsesquioxane, with a yield of 96.7%.

[0084] Nitrogen-containing cage-like polysilsesquioxane, selected from formula (V), where X is selected from -NH3. + The synthesis steps are as follows: 12 mL of a hexanol solution of trifluoromethanesulfonic acid (0.5 mol / L) was mixed with 180 μL of water. 3-Aminopropyltrimethoxysilane (2.0 mmol) was added under stirring at room temperature, followed by stirring for 2 h. The mixture was then heated to 50 °C in an open container until the solvent was completely evaporated. The crude product was then heated to 100 °C for 2 h, cooled to room temperature, and washed with a mixture of acetone / ethanol (1:1, v / v). The precipitate was separated by filtration and dried in a 70 °C oven for 5 h to obtain 0.472 g of a white solid powder. The product was then dissolved in an appropriate amount of propanol, and the insoluble matter was removed by filtration. The filtrate was heated to 50 °C in an open container until the solvent was completely evaporated, finally yielding 0.202 g of the target product, a nitrogen-containing cage-like polysilsesquioxane, with a yield of 40%.

[0085] A nitrogen-containing cage-like polysilsesquioxane, selected from formula (IV), where X is selected from -NH2, was synthesized as follows: 144 mL of deionized water (8 mol), 40 mL of propanol (0.66 mol), 10 mL of acetonitrile, and 636 μL of tetraethylammonium hydroxide (662.7 mg, 147.262 g / mol, density 1.041, 4.5 mmol) were added to a 500 mL flask. Then, 221 g of 3-aminopropyltriethylsilane (1 mol) was added with stirring over 10 minutes. The solution was heated to 50 °C, and after reacting for 24 h, white crystals appeared in the system. The precipitate was separated by filtration. The product was washed with H2O (100 mL) and cyclohexane (50 mL) and dried under vacuum at 100 °C for 24 h to obtain 79.2 g of the target product, a nitrogen-containing cage-like polysilsesquioxane, with a yield of 72.0%.

[0086] 3-Aminopropyltrimethoxysilane: Beijing Inokai Chemical Reagent Co., Ltd., molecular weight 179.29, density 1.01 g / mL, purity 97%.

[0087] 3-Aminopropyltriethoxysilane: Beijing Inokai Chemical Reagent Co., Ltd., molecular weight 191.34, purity 97%.

[0088] 3,5-Di-tert-butyl-4-hydroxybenzoic acid: Aladdin Reagent Co., Ltd., molecular weight 250.3, purity 98%.

[0089] 3,5-Di-tert-butyl-4-hydroxyphenylpropionic acid: Aladdin, molecular weight 278.4 g / mol, purity 98%.

[0090] 3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionic acid: Hong Kong Chemical Company Limited, molecular weight 236.3, purity 95%.

[0091] 3-(3-(2H-benzo[d][1,2,3]triazol-2-yl)-5-(tert-butyl)-4-hydroxyphenyl)propionic acid: Shanghai Maclean Biochemical Technology Co., Ltd., molecular weight 339.39, purity 97%.

[0092] 3-(3,4,5-Trihydroxyphenyl)propionic acid: Aurora Fine Chemicals, LLC (USA), molecular weight 198.175, purity 98%.

[0093] Evaluation and analysis methods:

[0094] Accelerated aging in an oven: A vacuum oven was used, kept in contact with the atmosphere, and the oven temperature was 150℃. Tensile strips and disc-shaped specimens of polyamide 6,6 were suspended in the oven, with appropriate spacing between the samples. After a certain aging time, the samples were removed for tensile strength and complex viscosity tests.

[0095] Tensile strength test: The tensile strength of the materials was tested using the Table Mounted Materials Testing System (Model 3365) from Instron, UK, according to the method shown in GB / T 1040.1-2018, at a tensile rate of 50 mm / min. The test temperature was room temperature, and at least 5 samples were tested in each group.

[0096] Complex viscosity testing: The test was conducted using a Tasmanian AR2000ex rotational rheometer with parallel plate clamps (25 mm diameter, 1 mm spacing). The test temperature was 270℃, and the sample was held at 270℃ for 3 minutes under a nitrogen atmosphere before testing. A frequency sweep mode with oscillating shear was selected, and a strain value of 1% was applied (to determine if the material was in the linear viscoelastic region through strain scanning). The complex viscosity was obtained at a frequency of 10 rad / s.

[0097] Infrared spectroscopy characterization: The polyamide 6,6 thin film samples were characterized using a Nicolet 6700 Fourier transform infrared spectrometer (FIR) from Thermo Fisher Scientific. Transmission mode was used, and the wavenumber range was 4000–650 cm⁻¹. -1 32 scans, 1cm resolution -1 When polyamide 6,6 undergoes oxidative degradation, carbonyl compounds are produced, as indicated by infrared spectroscopy at 1734 cm⁻¹. -1 The degree of oxidation of polyamide materials is characterized by the change in absorbance of carbonyl compounds at 1463 cm⁻¹. -1 The CH2 shear vibration absorption at that location is not sensitive to oxidative degradation, and therefore it was selected as the reference signal.

[0098] Solvent extraction of polyamide 6,6 samples: Some tensile strips and discs of polyamide 6,6 were immersed in ethylene glycol solution, and the system was maintained at 100°C for 120 hours. After that, the samples were removed from the ethylene glycol solution, and the residual ethylene glycol on the sample surface was removed with anhydrous ethanol. The samples were then placed in indoor air for one day before undergoing accelerated aging in an oven, followed by tensile strength and complex viscosity tests. In addition, polyamide 6,6 film samples were immersed in ethanol solution, and the system was maintained at 70°C for one week. After that, the samples were removed from the ethanol solution, and the samples were placed in indoor air for one day before undergoing accelerated aging in an oven and infrared spectroscopy characterization.

[0099] In this invention, except where expressly stated, any matters or issues not mentioned herein are directly applicable to those known in the art without any modification. Furthermore, any implementation described herein can be freely combined with one or more other implementations described herein, and the resulting technical solutions or concepts are considered part of the original disclosure or original record of this invention, and should not be regarded as new content not disclosed or anticipated herein, unless those skilled in the art consider the combination clearly unreasonable.

[0100] All features disclosed in this invention can be combined arbitrarily, and such combinations should be understood as the contents disclosed or recorded in this invention, unless those skilled in the art consider such combinations to be obviously unreasonable.

[0101] In this invention, alkylene refers to a free divalent group formed by losing two hydrogen atoms from two carbons of the same or different alkanes. For example, the alkylene of C2 can be -CH2-CH2- or -CH(CH3)-, and the alkylene of C3 can be -CH2-CH2-CH2- or -CH(CH3)-CH2- or -CH2-CH(CH3)-.

[0102] In this invention, the nitrogen-containing cage-like polysilsesquioxanes are selected from formulas IV to VI, representing cage-like polysilsesquioxanes T8, T... 10 T 12 The cage-like structure of the polysilsesquioxane is important, but because certain bases or hindered phenolic compounds containing carboxyl groups can catalyze the rearrangement of the cage-like structure of individual nitrogen-containing cage-like polysilsesquioxanes during the reaction, when the catalytic rearrangement activity of the base and hindered phenolic compounds containing carboxyl groups is greater than the cage-like structure stability of the nitrogen-containing cage-like polysilsesquioxane, regardless of whether the nitrogen-containing cage-like polysilsesquioxane is selected from T8, T... 10 T 12 Which structure ((IV)~(VI)) results in a cage-like polysilsesquioxane mixture containing hindered phenolic functional groups after the reaction, containing T8 and T? 10 T 12 Various cage-like structures; when the cage-like structure stability of nitrogen-containing cage-like polysilsesquioxanes is greater than the catalytic rearrangement activity of carboxyl-containing hindered phenolic compounds, the cage-like polysilsesquioxanes containing hindered phenolic functional groups obtained after the reaction have the same structure as the cage-like polysilsesquioxanes with nitrogen atoms selected before the reaction.

[0103] Example 1

[0104] In this embodiment, the nitrogen-containing cage-like polysilsesquioxane is selected from formula (IV), where X is an ammonium group -NH3. +R1 and R2 are tert-butyl-C(CH3)3, R3 is CO, and R4 is a C3 alkylene group -CH2-CH2-CH2-; the hindered phenolic compound containing a carboxyl group is selected by the general formula (VII), which is 3,5-di-tert-butyl-4-hydroxybenzoic acid; the condensing reagents are EDCI, HOBT, and DMAP; the base is N,N-diisopropylethylamine; and the solvent is N,N-dimethylformamide.

[0105]

[0106] Add 15 mL of N,N-dimethylformamide to a 50 mL three-necked flask, then add 11 mmol of 3,5-di-tert-butyl-4-hydroxybenzoic acid, 10 mmol of DMAP, 1 mmol of HOBT, 10 mmol of EDCI, and 25 mmol of N,N-diisopropylethylamine under stirring in an ice bath. After stirring for 1 hour, add 10 mL of a cage-like polysilsesquioxane containing nitrogen atoms (10 mmol of -NH3) + A solution of N,N-dimethylformamide was used to heat the reaction system to 80°C, and then the mixture was stirred for 12 hours. After the reaction was completed, an appropriate amount of ethyl acetate was added to dilute the system, and then 0.1 mol / L HCl aqueous solution was added dropwise to separate the organic layer. The organic layer was then washed with saturated sodium bicarbonate aqueous solution and concentrated brine, and the water in the organic layer was removed with anhydrous magnesium sulfate. The filtrate was filtered, and the solvent in the filtrate was removed by rotary evaporation. The solid was collected and purified by column chromatography to finally obtain 2.90 g (yield 85%) of a cage-like polysilsesquioxane mixture containing amide bonds and hindered phenolic functional groups.

[0107] Example 2

[0108] In this embodiment, the nitrogen-containing cage-like polysilsesquioxane is selected from formula (V), where X is -NH3. + R1 and R2 are tert-butyl-C(CH3)3, R3 is CO, and R4 is a C3 alkylene group -CH2-CH2-CH2-; the hindered phenolic compound containing a carboxyl group is selected by the general formula (VII), which is 3,5-di-tert-butyl-4-hydroxybenzoic acid; the condensing reagents are EDCI, HOBT, and DMAP; the base is N,N-diisopropylethylamine; and the solvent is N,N-dimethylformamide.

[0109]

[0110] Add 15 mL of N,N-dimethylformyl to a 50 mL three-necked flask, then add 11 mmol of 3,5-di-tert-butyl-4-hydroxybenzoic acid, 10 mmol of DMAP, 1 mmol of HOBT, 10 mmol of EDCI, and 25 mmol of N,N-diisopropylethylamine under stirring in an ice bath. After stirring for 1 h, add 10 mL of a cage-like polysilsesquioxane containing nitrogen atoms dissolved in it (10 mmol of -NH3). + The reaction system was heated to 80°C and stirred for 12 h using an N,N-dimethylformamide solution. After the reaction was completed, an appropriate amount of ethyl acetate was added to dilute the system, and then 0.1 mol / L HCl aqueous solution was added dropwise to separate the organic layer. The organic layer was then washed with saturated sodium bicarbonate aqueous solution and concentrated brine, and the water in the organic layer was removed with anhydrous magnesium sulfate. The filtrate was filtered, and the solvent in the filtrate was removed by rotary evaporation. The solid was collected and purified by column chromatography to finally obtain 2.81 g (yield 82%) of a cage-like polysilsesquioxane mixture containing amide bonds and hindered phenolic functional groups.

[0111] Example 3

[0112] In this embodiment, the nitrogen-containing cage-like polysilsesquioxane is selected from formula (IV), where X is -NH2, R1 and R2 are tert-butyl-C(CH3)3, R3 is CO, and R4 is a C3 alkylene group -CH2-CH2-CH2-; the carboxyl-containing hindered phenolic compound is selected from formula (VII), which is 3,5-di-tert-butyl-4-hydroxybenzoic acid; the condensation reagent is EDCI, HOBT, and DMAP; the base is N,N-diisopropylethylamine; and the solvent is dichloromethane.

[0113]

[0114] 15 mL of dichloromethane was added to a 50 mL three-necked flask. Then, under stirring in an ice bath, 11 mmol of 3,5-di-tert-butyl-4-hydroxybenzoic acid, 10 mmol of DMAP, 1 mmol of HOBT, 10 mmol of EDCI, and 25 mmol of N,N-diisopropylethylamine were added. After stirring for 1 h, 10 mL of a dichloromethane solution containing a nitrogen-containing cage-like polysilsesquioxane (10 mmol of -NH₂) was added. The reaction system was heated to 30 °C and stirred for 24 h. After the reaction was complete, the system was added dropwise to a 0.1 mol / L HCl aqueous solution to separate the organic layer. The organic layer was then washed with sodium bicarbonate aqueous solution and water, and the water in the organic layer was removed with anhydrous magnesium sulfate. The filtrate was filtered, and the solvent in the filtrate was removed by rotary evaporation. The solid was collected and purified by column chromatography to obtain 3.18 g (93% yield) of a cage-like polysilsesquioxane mixture containing amide bonds and hindered phenolic functional groups.

[0115] Example 4

[0116] In this embodiment, the nitrogen-containing cage-like polysilsesquioxane is selected from formula (IV), where X is -NH3. + R1 and R2 are tert-butyl-C(CH3)3, R3 is a C2 alkylene group -CH2-CH2-, and R4 is a C3 alkylene group -CH2-CH2-CH2-; the carboxyl-containing hindered phenolic compound selected by formula (VII) is 3,5-di-tert-butyl-4-hydroxyphenylpropionic acid; the condensation reagents are EDCI, HOBT, and DMAP; the base is triethylamine; and the solvent is N,N-dimethylformamide.

[0117]

[0118] Add 15 mL of N,N-dimethylformamide to a 50 mL three-necked flask, then add 11 mmol of 3,5-di-tert-butyl-4-hydroxyphenylpropionic acid, 10 mmol of DMAP, 1 mmol of HOBT, 10 mmol of EDCI, and 30 mmol of triethylamine under stirring in an ice bath. After stirring for 1 hour, add 10 mL of a cage-like polysilsesquioxane containing nitrogen atoms (10 mmol of -NH3) + The reaction system was heated to 60°C and stirred for 24 hours using an N,N-dimethylformamide solution. After the reaction was completed, an appropriate amount of ethyl acetate was added to dilute the system, and then 0.1 mol / L HCl aqueous solution was added dropwise to separate the organic layer. The organic layer was then washed with saturated sodium bicarbonate aqueous solution and concentrated brine, and the water in the organic layer was removed with anhydrous magnesium sulfate. The filtrate was filtered, and the solvent in the filtrate was removed by rotary evaporation. The solid was collected and purified by column chromatography to finally obtain 3.26 g (yield 88%) of a cage-like polysilsesquioxane mixture containing amide bonds and phenol-resistant functional groups.

[0119] Example 5

[0120] In this embodiment, the nitrogen-containing cage-like polysilsesquioxane is selected from formula (V), where X is -NH3. + R1 and R2 are tert-butyl-C(CH3)3, R3 is a C2 alkylene group -CH2-CH2-, and R4 is a C3 alkylene group -CH2-CH2-CH2-; the carboxyl-containing hindered phenolic compound selected by formula (VII) is 3,5-di-tert-butyl-4-hydroxyphenylpropionic acid; the condensation reagents are EDCI, HOBT, and DMAP; the base is N,N-diisopropylethylamine; and the solvent is N,N-dimethylformamide.

[0121]

[0122] Add 15 mL of N,N-dimethylformyl to a 50 mL three-necked flask, then add 11 mmol of 3,5-di-tert-butyl-4-hydroxyphenylpropionic acid, 10 mmol of DMAP, 1 mmol of HOBT, 10 mmol of EDCI, and 25 mmol of N,N-diisopropylethylamine under stirring in an ice bath. After stirring for 1 h, add 10 mL of a cage-like polysilsesquioxane containing nitrogen atoms dissolved in it (10 mmol of -NH3). + The reaction system was heated to 60°C and stirred for 24 hours using an N,N-dimethylformamide solution. After the reaction was completed, an appropriate amount of ethyl acetate was added to dilute the system, and then 0.1 mol / L HCl aqueous solution was added dropwise to separate the organic layer. The organic layer was then washed with saturated sodium bicarbonate aqueous solution and concentrated brine, and the water in the organic layer was removed with anhydrous magnesium sulfate. The filtrate was filtered, and the solvent in the filtrate was removed by rotary evaporation. The solid was collected and purified by column chromatography to finally obtain 3.13 g (yield 85%) of a cage-like polysilsesquioxane mixture containing amide bonds and hindered phenolic functional groups.

[0123] Example 6

[0124] In this embodiment, the nitrogen-containing cage-like polysilsesquioxane is selected from formula (IV), where X is -NH2, R1 and R2 are tert-butyl-C(CH3)3, R3 is a C2 alkylene group -CH2-CH2-, and R4 is a C3 alkylene group -CH2-CH2-CH2-; the carboxyl-containing hindered phenolic compound is selected from general formula (VII), which is 3,5-di-tert-butyl-4-hydroxyphenylpropionic acid; the condensation reagent is EDCI, HOBT, and DMAP; the base is triethylamine; and the solvent is dichloromethane.

[0125]

[0126] 15 mL of dichloromethane was added to a 50 mL three-necked flask. Then, under stirring in an ice bath, 11 mmol of 3,5-di-tert-butyl-4-hydroxyphenylpropionic acid, 10 mmol of DMAP, 1 mmol of HOBT, 10 mmol of EDCI, and 25 mmol of N,N-diisopropylethylamine were added. After stirring for 1 h, 10 mL of a dichloromethane solution containing a nitrogen-containing cage-like polysilsesquioxane (10 mmol of -NH₂) was added. The reaction system was heated to 30 °C and stirred for 24 h. After the reaction was complete, the system was added dropwise to a 0.1 mol / L HCl aqueous solution to separate the organic layer. The organic layer was then washed with sodium bicarbonate aqueous solution and water, and the water in the organic layer was removed with anhydrous magnesium sulfate. The filtrate was filtered, and the solvent in the filtrate was removed by rotary evaporation. The solid was collected and purified by column chromatography to obtain 3.37 g (91% yield) of a cage-like polysilsesquioxane mixture containing amide bonds and hindered phenolic functional groups.

[0127] Example 7

[0128] In this embodiment, the nitrogen-containing cage-like polysilsesquioxane is selected from formula (IV), where X is -NH3. + R1 and R2 are tert-butyl-C(CH3)3, R3 is CO, and R4 is a C3 alkylene group -CH2-CH2-CH2-; the hindered phenolic compound containing a carboxyl group is selected by the general formula (VII), which is 3,5-di-tert-butyl-4-hydroxybenzoic acid; the acyl chloride reagent is sulfoxide; the base is triethylamine; and the solvent is dichloromethane.

[0129]

[0130] In a 25 mL single-necked flask, 15 mL of dichloromethane was added. Then, under stirring in an ice bath, 11 mmol of 3,5-di-tert-butyl-4-hydroxybenzoic acid, 12 mmol of sulfoxide, and a few drops of N,N-dimethylformamide were added. The mixture was heated to room temperature and stirred for 12 h. The solvent and excess sulfoxide were then removed by rotary evaporation, and the resulting acyl chloride compound was dissolved in 10 mL of dichloromethane. In a 50 mL three-necked flask, 20 mL of dichloromethane, 25 mmol of triethylamine, and a nitrogen-containing cage-like polysilsesquioxane (10 mmol of -NH3) were added. + The mixture was stirred thoroughly, then nitrogen gas was introduced. The system was cooled in an ice bath, and the dichloromethane solution containing the acyl chloride compound was slowly added dropwise. After the addition was complete, the system was heated to room temperature and stirred for 12 hours. After the reaction was completed, the system was added dropwise to a 0.1 mol / L HCl aqueous solution to separate the organic layer. The organic layer was then washed with sodium bicarbonate aqueous solution and water, and the water in the organic layer was removed with anhydrous magnesium sulfate. The filtrate was filtered, and the solvent in the filtrate was removed by rotary evaporation. The solid was collected and washed with a mixed solvent of ethyl acetate and n-hexane (v / v = 1:5). The solid was filtered and separated, and dried in a vacuum oven to obtain 1.54 g (yield 45%) of a cage-like polysilsesquioxane mixture containing amide bonds and hindered phenolic functional groups.

[0131] Example 8

[0132] In this embodiment, the nitrogen-containing cage-like polysilsesquioxane is selected from formula (IV), where X is -NH2, R1 and R2 are tert-butyl-C(CH3)3, R3 is CO, and R4 is a C3 alkylene group -CH2-CH2-CH2-; the carboxyl-containing hindered phenolic compound is selected from formula (VII), which is 3,5-di-tert-butyl-4-hydroxybenzoic acid; the acyl chloride reagent is sulfoxide; the base is triethylamine; and the solvent is dichloromethane.

[0133]

[0134] Add 15 mL of dichloromethane to a 25 mL single-necked flask, then add 11 mmol of 3,5-di-tert-butyl-4-hydroxybenzoic acid, 12 mmol of sulfoxide, and a few drops of N,N-dimethylformamide under stirring in an ice bath. Heat to room temperature and stir for 12 h. Remove the solvent and excess sulfoxide by rotary evaporation, dissolving the resulting acyl chloride compound in 10 mL of dichloromethane. In a 50 mL three-necked flask, stir 20 mL of dichloromethane, 25 mmol of triethylamine, and a nitrogen-containing cage-like polysilsesquioxane (10 mmol of -NH₂) until homogeneous. Purge with nitrogen gas, cool the system in an ice bath, and slowly add the aforementioned dichloromethane solution containing the dissolved acyl chloride compound dropwise. After the addition is complete, heat the system to room temperature and stir for 12 h. After the reaction was completed, the system was added dropwise to a 0.1 mol / L HCl aqueous solution to separate the organic layer. The organic layer was then washed with sodium bicarbonate aqueous solution and water, and the water in the organic layer was removed with anhydrous magnesium sulfate. The filtrate was then filtered, and the solvent in the filtrate was removed by rotary evaporation. The solid was collected and washed with a mixed solvent of ethyl acetate and n-hexane (v / v = 1:5). The solid was then filtered and dried in a vacuum oven to obtain 2.22 g (65% yield) of a cage-like polysilsesquioxane mixture containing amide bonds and hindered phenolic functional groups.

[0135] Example 9

[0136] In this embodiment, the nitrogen-containing cage-like polysilsesquioxane is selected from formula (IV), where X is -NH3. + R1 and R2 are tert-butyl-C(CH3)3, R3 is a C2 alkylene group -CH2-CH2-, and R4 is a C3 alkylene group -CH2-CH2-CH2-; the carboxyl-containing hindered phenolic compound selected by formula (VII) is 3,5-di-tert-butyl-4-hydroxyphenylpropionic acid; the acyl chloride reagent is sulfoxide; the base is triethylamine; and the solvent is dichloromethane.

[0137]

[0138] In a 25 mL single-necked flask, 15 mL of dichloromethane was added. Then, under stirring in an ice bath, 11 mmol of 3,5-di-tert-butyl-4-hydroxyphenylpropionic acid, 12 mmol of sulfoxide, and a few drops of N,N-dimethylformamide were added. The mixture was heated to room temperature and stirred for 12 h. The solvent and excess sulfoxide were then removed by rotary evaporation, and the resulting acyl chloride compound was dissolved in 10 mL of dichloromethane. In a 50 mL three-necked flask, 20 mL of dichloromethane, 25 mmol of triethylamine, and a nitrogen-containing cage-like polysilsesquioxane (10 mmol of -NH3) were added. +The mixture was stirred thoroughly, then nitrogen gas was introduced. The system was cooled in an ice bath, and the dichloromethane solution containing the acyl chloride compound was slowly added dropwise. After the addition was complete, the system was heated to room temperature and stirred for 12 hours. After the reaction was completed, the system was added dropwise to a 0.1 mol / L HCl aqueous solution to separate the organic layer. The organic layer was then washed with sodium bicarbonate aqueous solution and water, and the water in the organic layer was removed with anhydrous magnesium sulfate. The filtrate was filtered, and the solvent in the filtrate was removed by rotary evaporation. The solid was collected and washed with a mixed solvent of ethyl acetate and n-hexane (v / v = 1:5). The solid was filtered and separated, and dried in a vacuum oven to obtain 1.96 g (yield 53%) of a cage-like polysilsesquioxane mixture containing amide bonds and hindered phenolic functional groups.

[0139] Example 10

[0140] In this embodiment, the nitrogen-containing cage-like polysilsesquioxane is selected from formula (IV), where X is -NH3. + R1 is tert-butyl-C(CH3)3, R2 is methyl-CH3, R3 is a C2 alkylene group -CH2-CH2-, and R4 is a C3 alkylene group -CH2-CH2-CH2-; the carboxyl-containing hindered phenolic compound selected by formula (VII) is 3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionic acid; the condensing reagents are EDCI, HOBT, and DMAP; the base is triethylamine; and the solvent is N,N-dimethylformamide.

[0141]

[0142] Add 15 mL of N,N-dimethylformamide to a 50 mL three-necked flask, then add 11 mmol of 3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionic acid, 10 mmol of DMAP, 1 mmol of HOBT, 10 mmol of EDCI, and 25 mmol of N,N-diisopropylethylamine under stirring in an ice bath. After stirring for 1 hour, add 10 mL of a cage-like polysilsesquioxane containing nitrogen atoms (10 mmol of -NH3) + The reaction system was heated to 80°C and stirred for 24 hours using an N,N-dimethylformamide solution. After the reaction was completed, an appropriate amount of ethyl acetate was added to dilute the system, and then 0.1 mol / L HCl aqueous solution was added dropwise to separate the organic layer. The organic layer was then washed with saturated sodium bicarbonate aqueous solution and concentrated brine, and the water in the organic layer was removed with anhydrous magnesium sulfate. The filtrate was filtered, and the solvent in the filtrate was removed by rotary evaporation. The solid was collected and purified by column chromatography to finally obtain the target product, a cage-like polysilsesquioxane mixture containing amide bonds and hindered phenolic functional groups, in a yield of 2.13 (71%).

[0143] Example 11

[0144] In this embodiment, the nitrogen-containing cage-like polysilsesquioxane is selected from formula (IV), where X is -NH3. + R1 is a hydroxyl group, R2 is a hydroxyl group, R3 is a C2 alkylene group (-CH2-CH2-), and R4 is a C3 alkylene group (-CH2-CH2-CH2-). The hindered phenolic compound containing a carboxyl group is selected from formula (VII), which is 3-(3,4,5-trihydroxyphenyl)propionic acid. The condensation reagents are EDCI, HOBT, and DMAP. The base is triethylamine. The solvent is N,N-dimethylformamide.

[0145]

[0146] Add 15 mL of N,N-dimethylformamide to a 50 mL three-necked flask, then add 11 mmol of 3-(3,4,5-trihydroxyphenyl)propionic acid, 10 mmol of DMAP, 1 mmol of HOBT, 10 mmol of EDCI, and 25 mmol of N,N-diisopropylethylamine under stirring in an ice bath. After stirring for 1 h, add 10 mL of a cage-like polysilsesquioxane containing nitrogen atoms dissolved in 10 mmol of -NH3. + The reaction system was heated to 70°C and stirred for 48 hours using an N,N-dimethylformamide solution. After the reaction was completed, an appropriate amount of ethyl acetate was added to dilute the system, and then 0.1 mol / L HCl aqueous solution was added dropwise to separate the organic layer. The organic layer was then washed with saturated sodium bicarbonate aqueous solution and concentrated brine, and the water in the organic layer was removed with anhydrous magnesium sulfate. The filtrate was filtered, and the solvent in the filtrate was removed by rotary evaporation. The solid was collected and purified by column chromatography to finally obtain 2.25g (yield 86%) of a cage-like polysilsesquioxane mixture containing amide bonds and hindered phenolic functional groups.

[0147] Example 12

[0148] In this embodiment, the nitrogen-containing cage-like polysilsesquioxane is selected from formula (IV), where X is -NH3. + R1 is tert-butyl-C(CH3)3, R2 is benzotriazolyl, R3 is a C2 alkylene group -CH2-CH2-, and R4 is a C3 alkylene group -CH2-CH2-CH2-; the carboxyl-containing hindered phenolic compound selected by formula (VII) is 3-(3-(2H-benzo[d][1,2,3]triazol-2-yl)-5-(tert-butyl)-4-hydroxyphenyl)propionic acid; the condensing reagents are EDCI, HOBT, and DMAP; the base is triethylamine; and the solvent is N,N-dimethylformamide.

[0149]

[0150] Add 15 mL of N,N-dimethylformamide to a 50 mL three-necked flask, then add 11 mmol of 3-(3-(2H-benzo[d][1,2,3]triazol-2-yl)-5-(tert-butyl)-4-hydroxyphenyl)propionic acid, 10 mmol of DMAP, 1 mmol of HOBT, 10 mmol of EDCI, and 25 mmol of N,N-diisopropylethylamine under stirring in an ice bath. After stirring for 1 h, add 10 mL of a cage-like polysilsesquioxane containing nitrogen atoms dissolved in 10 mmol of -NH3 + The reaction system was heated to 60°C and stirred for 48 hours using an N,N-dimethylformamide solution. After the reaction was completed, an appropriate amount of ethyl acetate was added to dilute the system, and then 0.1 mol / L HCl aqueous solution was added dropwise to separate the organic layer. The organic layer was then washed with saturated sodium bicarbonate aqueous solution and concentrated brine, and the water in the organic layer was removed with anhydrous magnesium sulfate. The filtrate was filtered, and the solvent in the filtrate was removed by rotary evaporation. The solid was collected and purified by column chromatography to finally obtain 1.81 g (yield 45%) of a cage-like polysilsesquioxane mixture containing amide bonds and hindered phenolic functional groups.

[0151] Experimental Example

[0152] Polyamide 6,6 containing 0.32 wt% of the cage-like polysilsesquioxane containing amide bonds and hindered phenolic functional groups prepared in Example 1 (the total amount of antioxidant and polyamide 6,6 is 100%, the same applies below) was used as experimental group 1; polyamide 6,6 containing 0.35 wt% of the cage-like polysilsesquioxane containing hindered phenolic functional groups prepared in Example 4 was used as experimental group 2; polyamide 6,6 containing 0.35 wt% of the cage-like polysilsesquioxane containing amide bonds and hindered phenolic functional groups prepared in Example 5 was used as experimental group 3; and polyamide 6,6 containing 0.3 wt% of antioxidant 1098 was used as the control group. The concentration of hindered phenolic functional groups in the above four groups of polyamide 6,6 samples was the same, all being 0.94 μmol / g. Sample composition information is shown in Table 1.

[0153] The samples were processed using a HAAKE Rheomex PTW16 / 40 twin-screw extruder from Thermo Fisher Scientific, Germany. Before processing, the polyamide 6,6 raw material was dried under vacuum at 100°C for 12 hours to remove moisture. The temperatures of each processing section were set to 275, 280, 285…285, 280, and 275°C, with a screw speed of 50 rpm. The extruded strips were granulated using a granulator, and then tensile test strips (meeting GB / T 1040.1-2018 requirements) were prepared by injection molding for tensile strength testing. Disc samples (25 mm in diameter, 1 mm thick) were prepared for complex viscosity characterization. Thin film samples (30 μm thick) were prepared by hot pressing for infrared spectroscopy characterization. The tensile strengths of the tensile test strips and disc samples before and after solvent treatment and accelerated aging in a 150°C oven after 120 hours of ethylene glycol extraction are shown in Table 2, and the complex viscosities are shown in Table 3. The infrared spectra of each thin film sample, after solvent treatment and 150°C accelerated aging in an oven for one week following extraction with ethanol at 70°C, were found to be at 1734 cm⁻¹. -1 The changes in absorbance at each location are shown in Tables 4 and 5.

[0154] Table 1 Sample composition:

[0155]

[0156] Table 2 Tensile strength (MPa) of polyamide 6,6 specimens:

[0157]

[0158]

[0159] Table 3. Complex viscosity (Pa·s) of polyamide 6,6 samples:

[0160]

[0161] Table 4 shows the infrared spectra of untreated polyamide 6,6 thin film samples at 1734 cm⁻¹. -1 Changes in absorbance at the location:

[0162] Sample No. 3 days 6 days 9 days 15 days 21 days 30 days 40 days 1 0.009 0.022 0.034 0.042 0.059 0.101 0.115 2 0.005 0.020 0.021 0.038 0.065 0.098 0.104 3 0.008 0.010 0.023 0.035 0.061 0.096 0.113 4 0.009 0.017 0.029 0.039 0.060 0.096 0.106

[0163] Table 5 shows the infrared spectra of polyamide 6,6 film samples after ethanol extraction at 1734 cm⁻¹. -1 Changes in absorbance at the location:

[0164] Sample No. 3 days 6 days 9 days 12 days 15 days 22 days 29 days 1 0.020 0.029 0.037 0.041 0.055 0.071 0.102 2 0.010 0.025 0.030 0.035 0.044 0.069 0.099 3 0.016 0.024 0.030 0.036 0.042 0.065 0.096 4 0.026 0.056 0.061 0.073 0.102 0.140 0.187

[0165] Results and analysis:

[0166] As shown in Tables 2, 3, 4, and 5, after accelerated aging in an oven, the tensile strength and complex viscosity of the untreated polyamide 6,6 samples with cage-type polysilsesquioxane antioxidants containing amide bonds and hindered phenolic functional groups prepared in Examples 1, 4, and 5 of this invention were comparable to those of the polyamide 6,6 samples with traditional antioxidant 1098. Furthermore, the infrared spectra of each sample were within the range of 1734 cm⁻¹. -1 The rate and magnitude of the increase in absorbance were similar to those of the polyamide 6,6 sample with added traditional antioxidant 1098. However, when the samples were subjected to ethylene glycol extraction followed by accelerated oven aging, the tensile strength and complex viscosity of the polyamide 6,6 sample with the cage-type polysilsesquioxane antioxidant containing amide bonds and hindered phenolic functional groups prepared in Examples 1, 4, and 5 of this invention were significantly higher than those of the polyamide 6,6 sample with added traditional antioxidant 1098. It should be noted that, because ethylene glycol is absorbed into the polyamide 6,6 matrix during ethylene glycol extraction and is not completely removed during the drying process, ethylene glycol molecules have a plasticizing effect on the matrix. Therefore, the tensile strength and complex viscosity of the samples after ethylene glycol extraction but before accelerated oven aging decreased compared to the time before extraction. During accelerated oven aging, the volatilization of ethylene glycol molecules and the disappearance of the plasticizing effect caused an initial increase in the tensile strength and complex viscosity of some samples. When polyamide 6,6 film samples were extracted with ethanol and then subjected to accelerated aging in an oven, the infrared spectrum of the polyamide 6,6 sample with added conventional antioxidant 1098 was significantly higher than that of the polyamide 6,6 sample with added hindered phenolic antioxidants prepared in Examples 1, 4, and 5 of this invention, at 1734 cm⁻¹. -1 The absorbance increases faster and by a greater margin. Furthermore, due to the larger size and molecular weight of the Si-O-Si cage-like skeleton of the product in Example 5, its solvent extraction resistance is also the best. Therefore, polyamide 6,6 sample 3 exhibits better resistance to ethylene glycol and ethanol extraction than polyamide 6,6 samples 1 and 2. In summary, the cage-like polysilsesquioxane containing amide bonds and hindered phenolic functional groups obtained in this invention can effectively improve the thermo-oxidative stability of polyamide 6,6 materials. Its anti-aging effect is comparable to commercially available antioxidant 1098, but it has stronger resistance to organic solvent extraction than commercially available antioxidant 1098.

[0167] Experiments have confirmed that the cage-like polysilsesquioxanes containing amide bonds and hindered phenolic functional groups with structures of formulas I, II, and III of this invention all have excellent antioxidant and extraction resistance effects.

[0168] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-described technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A cage-like polysilsesquioxane containing amide bonds and hindered phenolic functional groups, characterized in that, The structural formula is one or more of the following formulas I to III: Wherein, R1 and R2 are independently selected from at least one of hydrogen, alkyl, alkoxy, hydroxyalkyl, cycloalkyl, cycloalkylalkyl, aryl, aralkyl, heterocyclic, heterocyclic alkyl, carboxyl, ester, amide, amino, amine, halogen, nitro, cyano, oxycarbonyl, and aminocarbonyl; R3 and R4 are independently selected from alkylene groups having 0-20 carbon atoms.

2. The cage-like polysilsesquioxane containing amide bonds and hindered phenolic functional groups according to claim 1, characterized in that, R1 and R2 have 0-18 carbons, and R3 and R4 have 0-6 carbons, respectively; Preferably, at least one of R1 and R2 is a C3-C8 branched alkyl group.

3. The cage-like polysilsesquioxane containing amide bonds and hindered phenolic functional groups according to claim 1 or 2, characterized in that, R1 is H or methyl, R2 is a C3-C8 branched alkyl group; and / or, R3 is -CH2-CH2-, R4 is -CH2-CH2-CH2-.

4. A method for preparing cage-like polysilsesquioxanes containing amide bonds and hindered phenolic functional groups, characterized in that, include: Step 1: A nitrogen-containing cage-type polysilsesquioxane and a carboxyl-containing hindered phenolic compound are subjected to a condensation reaction in the presence of a condensing agent and a base to obtain a reaction mixture. Alternatively, hindered phenolic compounds containing carboxyl groups are first synthesized into acyl chloride compounds by the action of acyl chloride reagents, and then reacted with nitrogen-containing cage-type polysilsesquioxanes in the presence of a base to undergo an acylation reaction to obtain a reaction mixture; Step 2: The reaction mixture is post-treated to obtain cage-like polysilsesquioxanes containing amide bonds and hindered phenolic functional groups. Among them, the structural formula of the nitrogen-containing cage-like polysilsesquioxane is selected from one or more of the following structural formulas IV to VI, and the structure of the carboxyl-containing hindered phenolic compound is shown in formula VII: R1 and R2 are independently selected from at least one of hydrogen, alkyl, alkoxy, hydroxyalkyl, cycloalkyl, cycloalkylalkyl, aryl, aralkyl, heterocyclic, heterocyclic alkyl, carboxyl, ester, amide, amino, amine, halogen, nitro, cyano, oxycarbonyl, and aminocarbonyl. R3 and R4 are independently selected from alkylene groups having 0-20 carbon atoms; X is selected from amino-NH2 or ammonium-NH3. + .

5. The method for preparing cage-like polysilsesquioxanes containing amide bonds and hindered phenolic functional groups according to claim 4, characterized in that, In step 1, the condensing reagent is selected from at least one of N,N'-carbonyldiimidazole, dicyclohexylcarbodiimide, diisopropylcarbodiimide, 2-(7-azabenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate, O-(IH-benzotriazole-1-yl)-N,N,N',N'-tetramethylisourea hexafluoride, 1-propylphosphoric anhydride, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, 1-hydroxybenzotriazole, N-hydroxy-7-azabenzotriazole, and dimethylaminopyridine.

6. The method for preparing cage-like polysilsesquioxanes containing hindered phenolic functional groups according to claim 4, characterized in that, In step 1, the acyl chloride reagent is selected from one of phosphorus oxychloride, phosphorus pentachloride, oxalyl chloride, and thionyl chloride.

7. The method for preparing cage-like polysilsesquioxanes containing hindered phenolic functional groups according to claim 4, characterized in that, In step 1, the alkali is selected from at least one of triethylamine, N,N-diisopropylethylamine, pyridine, 1,8-diazabicycloundec-7-ene, triethylenediamine, sodium carbonate, potassium carbonate, sodium bicarbonate, sodium hydroxide, and potassium hydroxide.

8. The method for preparing cage-like polysilsesquioxanes containing hindered phenolic functional groups according to any one of claims 4-7, characterized in that, In step 1, the molar ratio of the nitrogen-containing cage-type polysilsesquioxane to the carboxyl-containing hindered phenolic compound, condensing agent or acyl chloride agent, and base is 1:(8-36):(8-50):(8-50).

9. The method for preparing cage-like polysilsesquioxanes containing hindered phenolic functional groups according to any one of claims 4-7, characterized in that, In step 1, the reaction temperature for the condensation or acylation reaction is 0℃-120℃, and the reaction time is 1~72h; Preferably, the reaction temperature is 25-80℃ and the reaction time is 12-24h.

10. The application of a cage-type polysilsesquioxane containing hindered phenolic functional groups as described in any one of claims 1-3 as an antioxidant for polymer materials.

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