Trapezoidal polysilsesquioxane containing amino and phenyl functional groups as well as preparation method and application of trapezoidal polysilsesquioxane

Abstract

The invention discloses trapezoidal polysilsesquioxane containing amino and phenyl functional groups as well as a preparation method and application of the trapezoidal polysilsesquioxane, in the structural general formula of the trapezoidal polysilsesquioxane, the amino functional group and the phenyl functional group are simultaneously grafted on a side chain, the polymerization degree is 5-1000, and the amino content is 2.0-4.0 wt%. According to the invention, functional groups containing amino groups and phenyl groups are grafted on the side chain of the trapezoidal polysilsesquioxane, so that not only can the number of reactive organic functional groups be increased, but also the thermal stability, compatibility and other properties of the trapezoidal polysilsesquioxane can be improved, and the trapezoidal polysilsesquioxane is easy to graft and modify and is highly regular; the dielectric constant and dielectric loss of the polymer material can be reduced, the thermal stability and damp-heat aging resistance can be improved, and the flexibility of a polymer matrix can be improved; the preparation method has the characteristics of greenness, environmental friendliness, mild conditions, simplicity in operation and easiness in industrial production.

Description

Technical Field

[0001] The present invention belongs to the technical field of ladder polysilsesquioxanes. Specifically, it relates to a ladder polysilsesquioxane containing amino and phenyl functional groups, a preparation method thereof, and an application thereof. Background Art

[0002] In recent years, with the continuous development of polymer synthesis methods, various functional polymer materials have emerged as if bamboo shoots after a spring rain. For example, for ladder polymers, the ideal cyclic ladder unit structure of ladder polymers should be uninterrupted, so that the molecular chain cannot rotate freely. To occur rotation or degradation, two chemical bonds on the same ring must be broken simultaneously. Obviously, the probability of breaking the molecular chain by simultaneously breaking two bonds on the same ring is much smaller than the probability of breaking a single bond accordingly. Therefore, ladder polymers exhibit good thermal, mechanical, radiation, and chemical stabilities compared to single-chain polymers linked by the same type of chemical bonds. Of course, its stability also depends on the regularity of the ladder structure.

[0003] In the synthesis research of ladder polymers, in 1960, Brown et al. first reported the synthesis of ladder-structured polysilsesquioxanes in J.Amer.Chem.Soc. They used phenyltrichlorosilane monomers to undergo a condensation reaction under the catalysis of potassium hydroxide and synthesized at a high temperature of 200 °C. However, the regularity of the ladder structure of the product obtained in this method has been questioned by relevant researchers and was finally overturned by Frey et al. Nevertheless, after Brown et al. proposed the hypothesis of a perfect ladder structure, synthesizing highly regular ladder polysilsesquioxanes has become a hot topic in the field of organosilicon synthesis. Since then, a large number of methods for synthesizing highly regular ladder polysilsesquioxanes have been developed. In these studies, some of the ladder polysilsesquioxanes synthesized by the methods only contain low-reactivity organic functional groups. Considering the increasing demand for reactive blending modification in some application fields, researchers hope to develop ladder polysilsesquioxanes with rich reactive organic functional groups. However, the existing synthesis methods require harsh synthesis conditions, cumbersome post-treatment steps, or a large amount of organic solvents to obtain highly regular reactive ladder polysilsesquioxanes.

[0004] Therefore, it is of great significance to prepare highly regular reactive ladder polysilsesquioxanes under relatively simple and mild conditions and use them in the research of polymer material modification.

[0005] In view of this, the present invention is specifically proposed. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a ladder-type polyhedral oligomeric silsesquioxane containing amino and phenyl functional groups. By grafting functional groups containing amino and phenyl on the side chains of the ladder-type polyhedral oligomeric silsesquioxane, not only can the number of reactive organic functional groups be increased, but also the properties such as thermal stability and compatibility of the ladder-type polyhedral oligomeric silsesquioxane can be improved. It is a ladder-type polyhedral oligomeric silsesquioxane that is easy to graft and modify and has a high degree of regularity.

[0007] To solve the above technical problems, the basic concept of the technical solution adopted by the present invention is:

[0008] A ladder-type polyhedral oligomeric silsesquioxane containing amino and phenyl functional groups has a structure as shown in the general formula (I):

[0009]

[0010] Among them, R is a functional group containing an amino group or a functional group containing a phenyl group;

[0011] In the general formula (I), the functional group containing an amino group and the functional group containing a phenyl group exist simultaneously.

[0012] Furthermore, it may also have a structure as shown in the general formula (Ⅱ):

[0013]

[0014] Among them, R1 is a functional group containing an amino group, and R2 is a functional group containing a phenyl group.

[0015] It may also have other structures. For example, the positions of R1 and R2 in the structure of the general formula (Ⅱ) are interchanged; or, a functional group containing an amino group and a functional group containing a phenyl group are respectively grafted in the vertical columns of the ladder structure, and the upper and lower positions can be interchanged; or, the upper row is grafted with functional groups containing an amino group, and the lower row is grafted with functional groups containing a phenyl group; or, the lower row is grafted with functional groups containing an amino group, and the upper row is grafted with functional groups containing a phenyl group, etc.

[0016] Furthermore, R1 is selected from one of 3-aminopropyl, N-(2-aminoethyl)-3-aminopropyl, N-methyl-3-aminopropyl, and N-phenyl-3-aminopropyl;

[0017] Preferably, R1 is selected from 3-aminopropyl or N-(2-aminoethyl)-3-aminopropyl.

[0018] Furthermore, R2 is selected from one of phenyl, benzyl, 4-vinylphenyl, phenethyl, 3-phenylpropyl, 3-(phenylamino), and 6-phenylhexyl;

[0019] Preferably, R2 is selected from phenyl.

[0020] Furthermore, n is an integer, and 5 ≤ n ≤ 1000.

[0021] Furthermore, the content of the amino group in the general formula (I) is 2.0 - 4.0 wt%, preferably 2.5 - 3.8 wt%.

[0022] In the above scheme, by grafting functional groups containing amino groups and phenyl groups on the side chains of the ladder polysilsesquioxane, compared with grafting functional groups at the end of the molecular structure, the number of reactive organic functional groups can be increased. The presence of the amino group can improve the compatibility of the ladder polysilsesquioxane, and the presence of the phenyl group can improve the thermal stability, rigidity, etc. of the ladder polysilsesquioxane. The prepared ladder polysilsesquioxane containing amino groups and phenyl groups has a high molecular weight, good stability, and good mechanical properties. It is a ladder polysilsesquioxane that is easy to graft and modify and has a high degree of regularity, which can improve its modification performance for polymer materials.

[0023] Moreover, by controlling the content of the amino group in the ladder polysilsesquioxane, it is beneficial for the reactive blending modification of the polymer, and at the same time, the yield of the ladder polysilsesquioxane is ensured.

[0024] A preparation method of a ladder polysilsesquioxane containing amino groups and phenyl groups, which is used to prepare a ladder polysilsesquioxane containing amino groups and phenyl groups as described above. The method includes the following steps:

[0025] (1) Adding a silane precursor to a catalyst and a solvent for reaction to obtain a crude reaction product;

[0026] (2) Post-treating the crude reaction product to obtain a ladder polysilsesquioxane containing amino groups and phenyl groups.

[0027] The silane precursor is selected from a silane precursor containing an amino group and a silane precursor containing a phenyl group;

[0028] Preferably, the silane precursor containing an amino group includes an amino group-containing siloxane and an amino group-containing chlorosilane, and the silane precursor containing a phenyl group includes a phenyl group-containing siloxane and a phenyl group-containing chlorosilane;

[0029] More preferably, the silane precursor containing an amino group is an amino group-containing siloxane, and the silane precursor containing a phenyl group is a phenyl group-containing siloxane;

[0030] More preferably, the feeding mode of the silane precursor is that the silane precursor containing an amino group and the silane precursor containing a phenyl group are premixed and then fed together.

[0031] In the above scheme, the ladder polysilsesquioxane containing amino and phenyl functional groups is obtained by hydrolysis and condensation reaction of amino-containing siloxane and phenyl-containing siloxane. The feeding mode of the silane precursor can be that the amino-containing silane precursor and the phenyl-containing silane precursor are premixed and then fed together, or the amino-containing silane precursor is first fed and hydrolyzed and condensed for a certain time, and then the phenyl-containing silane precursor is fed, or the phenyl-containing silane precursor is first fed and hydrolyzed and condensed for a certain time, and then the amino-containing silane precursor is fed.

[0032] Preferably, the amino-containing silane precursor and the phenyl-containing silane precursor are premixed and then fed together. In this way, the two silane precursors carry out co-condensation reaction simultaneously, and a ladder structure can be directly formed through the direct action of the amino- and phenyl-containing functional groups.

[0033] If the feeding mode of the silane precursor is sequential feeding, the hydrolysis and condensation time of the first-fed silane precursor is 1-12 h, preferably 4-8 h; after the first-fed silane precursor undergoes hydrolysis and condensation to form a self-condensation product, then another silane precursor is fed and also undergoes hydrolysis and condensation to form a self-condensation product, and the two self-condensation products react to form the target product.

[0034] Furthermore, the total molar concentration of the amino-containing silane precursor and the phenyl-containing silane precursor is 0.05-0.8 mo1 / L, preferably 0.1-0.5 mo1 / L.

[0035] Furthermore, the molar ratio of the amino-containing silane precursor to the phenyl-containing silane precursor is (0.5-5):1, preferably (0.5-3):1, and more preferably 0.5:1.

[0036] In the above scheme, when the total molar concentration of the silane precursor is lower than 0.1-0.5 mo1 / L, the product yield is too low. After exceeding this concentration, the reaction rate is too fast, resulting in a decrease in the regularity of the ladder co-condensation product. When the molar ratio of the amino-containing silane precursor to the phenyl-containing silane precursor is less than (0.5-3):1, the amino content in the final product is too low, which is not conducive to the reactive blending modification of the polymer. After exceeding this ratio, the product yield is too low. When it is preferably 1:1, the amino content of the obtained product is the highest and the yield is relatively high.

[0037] Preferably, the molar ratio of the catalyst to the total molar amount of the amino-containing siloxane and the phenyl-containing siloxane is (0.01-2):1, preferably (0.05-1):1.

[0038] In the above solution, when the ratio of the number of moles of the catalyst to the total number of moles of the amino-containing siloxane and the phenyl-containing siloxane is less than (0.05 - 1):1, the catalytic efficiency is too low, the reaction rate slows down, and the yield decreases. When it is greater than this ratio, the catalyst concentration is too high, the reaction is violent, and the regularity of the obtained ladder co-condensation product decreases.

[0039] Furthermore, the amino-containing silane precursor is selected from one of 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltriethoxysilane, N-methyl-3-aminopropyltrimethoxysilane, N-methyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, and N-phenyl-3-aminopropyltriethoxysilane;

[0040] The phenyl-containing silane precursor is selected from one of phenyltrimethoxysilane, phenyltriethoxysilane, phenyltrichlorosilane, benzyltrimethoxysilane, benzyltriethoxysilane, benzyltrichlorosilane, (4-vinylphenyl)trimethoxysilane, phenethyltrimethoxysilane, phenethyltriethoxysilane, phenethyltrichlorosilane, 3-(phenylamino)propyltrimethoxysilane, 3-(phenylamino)propyltriethoxysilane, 3-phenylpropyltrichlorosilane, and 6-phenylhexyltrichlorosilane;

[0041] Preferably, the amino-containing silane precursor is selected from 3-aminopropyltriethoxysilane or N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, and the phenyl-containing silane precursor is selected from phenyltrimethoxysilane.

[0042] In the above solution, since chlorosilane is more prone to hydrolysis than alkoxysilane, the reaction is more violent, and the regularity of the generated product is lower. Therefore, the preferred raw material is alkoxysilane. The preferred amino and phenyl silanes are more common and easily available raw materials.

[0043] Furthermore, in step (1), the solvent can be water, a mixed solvent of water and ethanol, a mixed solvent of water and tetrahydrofuran, a mixed solvent of water and acetone, etc.; preferably water, which simplifies the post-treatment process and is environmentally friendly.

[0044] Furthermore, the catalyst is selected from basic inorganic salts such as sodium hydroxide, potassium hydroxide, potassium carbonate, and sodium carbonate.

[0045] Furthermore, in step (1), the reaction temperature is 0 - 80°C, preferably 25 - 60°C;

[0046] Preferably, the reaction time after the silane precursor is fed is 1 - 24 h, preferably 2 - 8 h;

[0047] Preferably, in step (2), the post-treatment includes filtering the reaction system by suction, washing it with deionized water multiple times, drying, grinding into powder, washing it with ethyl acetate multiple times, and drying again.

[0048] Preferably, the drying is carried out by blowing air, and the temperature is 80 °C; the re-drying is carried out under vacuum, the temperature is 60 - 80 °C, and the vacuum degree is -0.1 to -0.05 MPa.

[0049] In the above scheme, during the washing process, the catalyst and by-products with low degree of condensation are dissolved and rinsed off by water and ethyl acetate, improving the purity of the target product.

[0050] The application of a ladder-type polyhedral oligomeric silsesquioxane containing amino and phenyl functional groups is to apply the ladder-type polyhedral oligomeric silsesquioxane containing amino and phenyl functional groups as described above in the modification treatment of polymer materials. The polymer materials include at least polyamide, polyethylene, polypropylene, polyvinyl chloride, epoxy resin, and bismaleimide resin;

[0051] Preferably, the polymer materials are polyamide, epoxy resin, and bismaleimide resin.

[0052] In the above scheme, the ladder-type polyhedral oligomeric silsesquioxane has a special linear ladder-shaped double-chain Si-O-Si skeleton, and has higher mechanical properties, heat-oxygen stability, and hydrolysis resistance than single-chain linear polysiloxane; the higher molecular weight and double-chain structure endow the ladder-type polyhedral oligomeric silsesquioxane with excellent thermal stability and mechanical properties; the regular ladder structure enables them to have good solubility in organic solvents, facilitating their solution blending and compounding with some polymers; the reactive organic R-Si segments enable them to carry out reactive blending with the polymer matrix, thereby improving their dispersibility in the polymer matrix and compatibility with the polymer matrix.

[0053] The ladder-type polyhedral oligomeric silsesquioxane containing amino and phenyl functional groups prepared by the present invention is an easily graft-modified and highly regular ladder-type polyhedral oligomeric silsesquioxane, which can reduce the dielectric constant and dielectric loss of polymer materials, improve the thermal stability and resistance to humid heat aging performance, increase the flexibility of the polymer matrix, and it has good dispersion, good compatibility, high thermal stability, and strong extraction resistance in polymers, improving its modification performance for polymer materials and can be used as a modified filler for polymer materials.

[0054] After adopting the above technical scheme, the present invention has the following beneficial effects compared with the prior art:

[0055] 1. The present invention provides a ladder polysilsesquioxane containing amino and phenyl functional groups. By grafting functional groups containing amino and phenyl on the side chains of the ladder polysilsesquioxane, it can not only increase the number of reactive organic functional groups, but also improve the properties such as the thermal stability and compatibility of the ladder polysilsesquioxane. It is a ladder polysilsesquioxane that is easy to graft-modify and highly regular.

[0056] 2. The ladder polysilsesquioxane containing amino and phenyl functional groups provided by the present invention can reduce the dielectric constant and dielectric loss of polymer materials, improve the thermal stability and resistance to wet heat aging performance, increase the flexibility of the polymer matrix, and it has good dispersion, compatibility, high thermal stability and strong extraction resistance in the polymer. It is a modifier with stable structure, multiple effects and environmental friendliness.

[0057] 3. The present invention also provides a preparation method of a ladder polysilsesquioxane containing amino and phenyl functional groups, which has the characteristics of green environmental protection, mild conditions, simple operation and easy industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] The drawings, as part of this application, are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention, but do not constitute an improper limitation to the present invention. Obviously, the drawings described below are only some embodiments. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts. In the drawings:

[0059] Figure 1 is the liquid nuclear magnetic resonance silicon spectrum of the product obtained in Example 1 of the present invention;

[0060] Figure 2 is the XRD diffraction spectrum of the products obtained in Example 1 and Example 4 of the present invention;

[0061] Figure 3 is the graph of the change of the dielectric constant (a) and dielectric loss (b) of the polymer sample with frequency in Experimental Example 3 of the present invention;

[0062] Figure 4 is the graph of the tensile strength test results of the polymer sample before and after boiling water aging in Experimental Example 3 of the present invention.

[0063] It should be noted that these drawings and text descriptions are not intended to limit the scope of the concept of the present invention in any way, but to illustrate the concept of the present invention to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0064] To make the objectives, technical solutions, and advantages of the present invention clearer, the following describes the technical solutions of the present invention clearly and completely in combination with some embodiments. Those skilled in the art can understand that the following embodiments are only used to explain the technical principle of the present invention and are not intended to limit the protection scope of the present invention. For example, although the steps of the method of the present invention are described in a specific order in this application, these orders are not restrictive. Without departing from the basic principle of the present invention, those skilled in the art can execute the steps in a different order.

[0065] Example 1

[0066] (1) Add 600 ml of 0.01 mol / L NaOH aqueous solution to a 1 L three-necked flask, stir mechanically at 300 rpm, and keep the system temperature stable at 30 °C. Mix 27.067 g of phenyltrimethoxysilane and 16.271 g of 3-aminopropyltriethoxysilane evenly in a beaker to prepare a transparent silane mixture. Add the silane mixture to the three-necked flask and stop stirring after reacting for 2 h.

[0067] (2) Filter the reaction system to obtain a solid product. Wash the solid product three times with deionized water to remove the sodium hydroxide and by-products with low condensation degree that may adhere to the solid product to obtain a crude product. Dry it to constant weight in a blast drying oven at 80 °C, grind it into powder, and then wash the solid three times with ethyl acetate. Finally, dry the solid product to constant weight in a vacuum oven at a temperature of 60 °C and a vacuum degree of -0.1 to -0.05 MPa to obtain a ladder-type polyhedral oligomeric silsesquioxane containing amino and phenyl groups.

[0068] The reaction equation is shown in (Ⅲ):

[0069]

[0070] The specific hydrolysis and condensation process is shown in (Ⅳ):

[0071]

[0072] The silane precursors phenyltrimethoxysilane and 3-aminopropyltriethoxysilane first undergo hydrolysis reactions to generate their corresponding trihydroxysilanes, and then the two trihydroxysilanes undergo dehydration condensation under the action of a catalyst to form the final product. This method is a product obtained by the direct co-condensation of two functional silanes. The reactive 3-aminopropyl functional group in the product is located on the side chain of the inorganic siloxane backbone, and its content is much higher than that of a similar product obtained by grafting 3-aminopropyltriethoxysilane at the end.

[0073] When R1 is phenyl and R2 is 3-aminopropyl, the structural formula of the prepared target product is shown in Figure (Ⅴ):

[0074]

[0075] The liquid nuclear magnetic resonance silicon spectrum and XRD diffraction spectrum of the product are shown in Figure 1 and Figure 2 respectively.

[0076] It can be seen from Figure 2 that the polyhedral oligomeric silsesquioxane product containing amino and phenyl groups synthesized in Example 1 has a relatively sharp diffraction peak and a broadened diffraction peak at 7° and 19°, which represent the trapezoidal width and thickness of the ladder structure respectively, showing the typical characteristics of the ladder structure.

[0077] It can be seen from Figure 1 that the resonance signals near -78, -69 and -65 ppm correspond to Ph-T 3 [PhSi-(OSi)3], Ph-T 2 [PhSiOH-(OSi)2] and NH2(CH2)3-T 3 [NH2(CH2)3Si-(OSi)3]. It should be noted that although the signal from Ph-T 2 [PhSiOH-(OSi)2] was monitored, its integral area is almost zero, which is negligible compared with Ph-T 3 and NH2(CH2)3-T 3 , indicating that it comes from the end structure of the ladder-like structure. In the generally accepted interpretation, 29 in the Si NMR spectrum, the maximum full width at half maximum (Δ1 / 2) of the T 3 peak decreases with the increase in the regularity of the ladder polyhedral oligomeric silsesquioxane. The Δ1 / 2 shown by the ladder polyhedral oligomeric silsesquioxane containing amino and phenyl groups is 197 Hz. This is comparable to the report of LPSQs synthesized by Choi (CHOI S-S, et al. Macromolecules, 2015, 6063 - 6070) before, and the Δ1 / 2 of the latter is 172 Hz. N-PPSQ has a higher proportion of T3 siloxane structure and a smaller Δ1 / 2, strongly proving its high regularity.

[0078] Example 2

[0079] (1) Add 600 ml of 0.01 mol / L NaOH aqueous solution to a 1 L three-necked flask, stir mechanically at 300 rpm, and keep the system temperature stable at 30 °C. Add 16.271 g of 3-aminopropyltriethoxysilane to the three-necked flask, pre-hydrolyze and condense for 4 h, and then add 27.067 g of phenyltrimethoxysilane. Stop stirring after reacting for 6 h;

[0080] (2) Filter the reaction system to obtain a solid product. Wash the solid product three times with deionized water to remove the sodium hydroxide and by-products with low condensation degree that may adhere to the solid product, obtaining a crude product. Dry it to constant weight in a blast drying oven at 80 °C, grind it into a powder, and then wash the solid three times with ethyl acetate. Finally, dry the solid product to constant weight in a vacuum drying oven at a temperature of 60 °C and a vacuum degree of -0.1 to -0.05 MPa to obtain a ladder-type polyhedral oligomeric silsesquioxane containing amino and phenyl groups.

[0081] Example 3

[0082] (1) Add 600 ml of 0.01 mol / L NaOH aqueous solution to a 1 L three-necked flask, stir mechanically at 300 rpm, and keep the system temperature stable at 30 °C. Mix 27.067 g of phenyltrimethoxysilane and 16.343 g of N-(2-aminoethyl)-3-aminopropyltrimethoxysilane evenly in a beaker to prepare a transparent silane mixture. Add the silane mixture to the three-necked flask and stop stirring after reacting for 2 h.

[0083] (2) Filter the reaction system to obtain a solid product. Wash the solid product three times with deionized water to remove the sodium hydroxide and by-products with low condensation degree that may adhere to the solid product, obtaining a crude product. Dry it to constant weight in a blast drying oven at 80 °C, grind it into a powder, and then wash the solid three times with ethyl acetate. Finally, dry the solid product to constant weight in a vacuum drying oven at a temperature of 60 °C and a vacuum degree of -0.1 to -0.05 MPa to obtain a ladder-type polyhedral oligomeric silsesquioxane containing amino and phenyl groups.

[0084] Example 4

[0085] (1) Add 600 ml of 0.01 mol / L NaOH aqueous solution to a 1 L three-necked flask, stir mechanically at 300 rpm, and keep the system temperature stable at 30 °C. Add 16.343 g of N-(2-aminoethyl)-3-aminopropyltrimethoxysilane to the three-necked flask and pre-hydrolyze and condense for 4 h, then add 27.067 g of phenyltrimethoxysilane and stop stirring after reacting for 6 h.

[0086] (2) Filter the reaction system to obtain a solid product. Wash the solid product three times with deionized water to remove the sodium hydroxide and by-products with low condensation degree that may adhere to the solid product, obtaining a crude product. Dry it to constant weight in a blast drying oven at 80 °C, grind it into a powder, and then wash the solid three times with ethyl acetate. Finally, dry the solid product to constant weight in a vacuum drying oven at a temperature of 60 °C and a vacuum degree of -0.1 to -0.05 MPa to obtain a ladder-type polyhedral oligomeric silsesquioxane containing amino and phenyl groups.

[0087] When R1 is phenyl and R2 is N-(2-aminoethyl)-3-aminopropyl, the structural formula of the prepared target product is as shown in (Ⅵ):

[0088]

[0089] The XRD diffraction pattern of the target product is as Figure 2 shown, and it can be clearly seen that the product has a typical ladder structure.

[0090] Comparative Example 1

[0091] (1) Add 600 ml of 0.01 mol / L NaOH aqueous solution to a 1 L three-necked flask, stir mechanically at 300 rpm, and keep the system temperature stable at 30 °C. Add 27.067 g of phenyltrimethoxysilane to the three-necked flask, stop stirring after reacting for 2 h; filter the reaction system to obtain a solid product, wash the solid product three times with deionized water to remove the sodium hydroxide and by-products with low degree of condensation that may adhere to the solid product, and obtain a crude product; dry it to constant weight in a blast drying oven at 80 °C, grind it into powder, and then wash the solid three times with ethyl acetate; finally, dry the solid product to constant weight in a vacuum drying oven at a temperature of 60 °C and a vacuum degree of -0.1 to -0.05 MPa to obtain a ladder-type polyhedral oligomeric silsesquioxane containing phenyl, and its structural formula is as shown in (Ⅶ):

[0092]

[0093] (2) Add 600 ml of 0.01 mol / L NaOH aqueous solution to a 1 L three-necked flask, stir mechanically at 300 rpm, and keep the system temperature stable at 30 °C. Add 16.271 g of 3-aminopropyltriethoxysilane to the three-necked flask, stop stirring after reacting for 2 h; filter the reaction system to obtain a solid product, wash the solid product three times with deionized water to remove the sodium hydroxide and by-products with low degree of condensation that may adhere to the solid product, and obtain a crude product; dry it to constant weight in a blast drying oven at 80 °C, grind it into powder, and then wash the solid three times with ethyl acetate; finally, dry the solid product to constant weight in a vacuum drying oven at a temperature of 60 °C and a vacuum degree of -0.1 to -0.05 MPa to obtain a ladder-type polyhedral oligomeric silsesquioxane containing amino and phenyl, and its structural formula is as shown in (Ⅷ):

[0094]

[0095] Comparative Example 2

[0096] Compared with Example 1, the steps of washing the process product with deionized water and ethyl acetate are omitted, and other conditions remain unchanged, to obtain a ladder-type polyhedral oligomeric silsesquioxane containing amino and phenyl.

[0097] Experimental Example 1

[0098] In this experimental example, the products prepared in Examples 1 to 4, Comparative Examples 1 and 2 were tested.

[0099] Compared with Example 1, the product obtained in Example 2 has lower regularity. This is because when 3-aminopropyltriethoxysilane and phenyltrimethoxysilane are fed simultaneously, the π-π stacking interaction between benzene rings, the hydrogen bond interaction between Si-OH, and the NH…N hydrogen bond interaction can achieve the best synergistic effect, resulting in the highest regularity of the final product. Similarly, compared with Example 3, the product obtained in Example 4 has lower regularity.

[0100] The nitrogen content of the sample obtained in Comparative Example 1 is much lower than that of the sample obtained in Experimental Example 1, which is not conducive to the subsequent reactive blending modification of the polymer.

[0101] Taking Example 1 as an example, when phenyltrimethoxysilane and 3-aminopropyltriethoxysilane undergo random hydrolysis and condensation in the system, in addition to the co-condensation products of the two, self-condensation products of each will inevitably be generated. Among them, 3-aminopropyltriethoxysilane cannot form solid self-condensation products under the reaction conditions used in this study, and the hydrolysis and condensation products are always dissolved in water. While phenyltrimethoxysilane can form white solid self-condensation products, which are mixed with the co-condensation products to form a mixture. Directly washing the crude product with a solvent in the wet state will cause some of the co-condensation products to also dissolve in it, and it is impossible to effectively separate them from the self-condensation products of phenyltrimethoxysilane. However, when the crude product is washed with water and dried, the solubility of the co-condensation products in acetone and ethyl acetate decreases significantly. Therefore, first wash with deionized water to remove the silane precursors with lower hydrolysis and condensation degree and the self-condensation products of 3-aminopropyltriethoxysilane. After the product is dried, then wash with ethyl acetate to remove the self-condensation products of phenyltrimethoxysilane, thereby obtaining a pure ladder-shaped co-condensation product. In Comparative Example 2, the self-condensation products of the silane precursors in the product were not removed, and the catalyst and products with low condensation degree were not washed, and the product was not further purified. The obtained product was mixed with self-condensation products, resulting in an impure target product.

[0102] Experimental Example 2

[0103] On the basis of Example 1, by changing the total molar concentration of the silane precursors and the molar ratio of the amino-containing silane precursor to the phenyl-containing silane precursor, Examples 5 to 11 and Comparative Examples 3 to 6 were obtained, and the prepared products were tested. The results are shown in Table 2.

[0104] Table 2

[0105]

[0106] As can be seen from Table 2, under the same other conditions, when changing the total molar concentration of the silane precursor, when the total molar concentration of the silane precursor is in the range of 0.05 - 0.8 mo1 / L, such as in Examples 1, 5 to 8, the yield of the ladder co - condensation product is relatively high; especially when the total molar concentration of the silane precursor is within 0.1 - 0.5 mo1 / L, such as in Examples 1, 6 and 7, the proportion of the phenyl self - condensation product is relatively low and the yield of the ladder co - condensation product is relatively high. However, when the total molar concentration of the silane precursor is lower than 0.1 - 0.5 mo1 / L, such as in Comparative Example 3, the yield of the ladder co - condensation product is too low; after being higher than this concentration, such as in Comparative Example 4, the reaction rate is too fast, the proportion of the phenyl self - condensation product is too high, and the yield of the ladder co - condensation product decreases.

[0107] Under the same other conditions, when changing the molar ratio of the amino - containing silane precursor to the phenyl - containing silane precursor, when the molar ratio is in the range of (0.5 - 5):1, such as in Examples 1, 9 to 11, the amino content in the ladder co - condensation product is relatively high, which is beneficial for the reactive blending modification of the polymer; especially when the molar ratio is in the range of (0.5 - 3):1, such as in Examples 1, 9, its modification performance is more excellent. However, when the molar ratio of the amino - containing silane precursor to the phenyl - containing silane precursor is lower than (0.5 - 5):1, such as in Comparative Example 5, the amino content in the ladder co - condensation product is too low, which is not conducive to the reactive blending modification of the polymer, and after being greater than this ratio, such as in Comparative Example 6, the yield of the ladder co - condensation product is too low and the amino content is also low.

[0108] As in Example 1, when the total molar concentration of the silane precursor is 0.35 mo1 / L and the molar ratio of the amino - containing silane precursor to the phenyl - containing silane precursor is 0.5:1, the amino content in the ladder co - condensation product is the highest, the proportion of the phenyl self - condensation product is less, and the yield of the ladder co - condensation product is the highest.

[0109] It should be noted that the amino content in the ladder co - condensation product is affected by at least the total molar concentration of the silane precursor and the molar ratio of the amino - containing silane precursor to the phenyl - containing silane precursor, but the influence is not linearly variable.

[0110] Experimental Example 3

[0111] Take 30 g of E - 51 epoxy resin, and add 4wt%, 6wt%, 10wt%, 14wt% of the amino - and phenyl - containing ladder polysilsesquioxane prepared in Example 1 as the modified experimental groups, and do not add a modifier as the control group. The sample composition information is shown in Table 3.

[0112] Table 3

[0113] Number Resin Modifier Content 1 E-51 None 0 2 E-51 Product of Example 1 4％ 3 E-51 Product of Example 1 6％ 4 E-51 Product of Example 1 10％ 5 E-51 Product of Example 1 14％

[0114] At 120 °C, the ladder poly(silsesquioxane) containing amino and phenyl groups in the corresponding mass was dissolved in a certain volume of DMF by magnetic stirring, and then the transparent solution was poured into the epoxy resin matrix. The system was stirred until a transparent mixture was obtained. After that, DMF was completely removed from the mixture by rotary evaporation at 120 °C. A curing agent IPDA (the stoichiometric ratio of epoxy groups to active hydrogen was 1:1) was added to the mixture, and then it was stirred until a transparent and homogeneous system was obtained. The mixture was degassed repeatedly by vacuum pumping for 5 minutes to remove the air bubbles in the system. Finally, the mixture was quickly poured into a stainless-steel mold and cured at 80 °C for 4 hours and at 150 °C for 2 hours. After cooling to room temperature in the furnace, it was demolded to obtain the modified epoxy resin material. The control group was prepared by the same process without adding the ladder poly(silsesquioxane) containing amino and phenyl groups as the modifier.

[0115] (1) Mechanical property tests: Tensile and flexural properties were tested using an Instron 3365 universal materials testing machine (Instron, USA). According to the standard of GB / T 1040.2 - 2006, tensile samples with a thickness of 3.5 mm were tested at a speed of 2 mm / min. According to the GB / T 9341 - 2000 standard, flexural properties were tested in a three-point bending mode at a constant speed of 2 mm / min with a thickness of 4 mm. According to the GB / T 8762 - 1998 standard, the non-notched impact strength of the samples was obtained using an XJC-250 pendulum impact testing machine (China). Each sample was tested at least five times, and the results were averaged. The test results are shown in Table 4.

[0116] Table 4

[0117]

[0118] As can be seen from Table 4, specimens 2, 3, 4, and 5 have higher impact strength than the pure E-51 specimen. When 10 wt.% of the ladder poly(silsesquioxane) containing amino and phenyl functional groups prepared by the synthesis method of the present invention was added, the impact strength of the specimen increased by 73% compared with the pure E-51 specimen. In addition, compared with the pure E-51 specimen, the Young's modulus, flexural strength, and flexural modulus of specimens 2, 3, 4, and 5 all increased, while the tensile strength was basically maintained. Therefore, the ladder poly(silsesquioxane) containing amino and phenyl functional groups prepared by the synthesis method of the present invention can improve the toughness of E-51 resin without sacrificing its strength and modulus.

[0119] (2) Solvent extraction resistance experiment: Immerse the Soxhlet extraction devices with appropriate weighed samples 1 and 5 in an oil bath at 170 °C for heating and maintain the temperature, using N,N-dimethylformamide as the Soxhlet extraction solvent. After 72 hours, take out the samples and dry them to constant weight by vacuum drying in a vacuum oven at 120 °C to remove the residual solvent, and then weigh the samples after extraction. The test results are shown in Table 5.

[0120] Table 5

[0121] Number Mass before extraction (g) Mass after extraction (g) Mass loss rate (%) 1 7.674 7.445 2.98 5 10.293 10.116 1.72

[0122] As can be seen from Table 5, for the epoxy resin samples containing the ladder polyhedral oligomeric silsesquioxane with amino and phenyl functional groups prepared by the synthesis method of the present invention with 14 wt.%, after 72 hours of extraction with N,N-dimethylformamide, the mass loss rate is lower than that of pure epoxy resin. It can be seen that the ladder polyhedral oligomeric silsesquioxane with amino and phenyl functional groups prepared by the synthesis method of the present invention can improve the extraction resistance of epoxy resin to a certain extent. In addition, since the ladder polyhedral oligomeric silsesquioxane with amino and phenyl functional groups prepared by the synthesis method of the present invention can be dissolved in N,N-dimethylformamide, this result also proves that it has undergone reactive blending with the epoxy resin matrix and has not been extracted from the system by DMF.

[0123] (3) Dielectric property test: Evaluate by a Concept40 broadband dielectric spectrometer (Novocontrol, Germany) at room temperature in the frequency range of 102 - 106 Hz. The sample is a disc-shaped thin sheet with a diameter of 20 mm and a thickness of 1 mm. The test results are shown in Figure 3 .

[0124] As can be seen from Figure 3 , after introducing the ladder polyhedral oligomeric silsesquioxane with amino and phenyl functional groups prepared by the synthesis method of the present invention, both the dielectric constant and the dielectric loss of the E-51 resin matrix have decreased. Specifically, the dielectric constant and dielectric loss of the pure E-51 sample at a frequency of 10 6 Hz are 3.31 and 0.052 respectively, while those of sample 5 at a frequency of 10 6 Hz are 3.15 and 0.019 respectively. It can be seen that the ladder polyhedral oligomeric silsesquioxane with amino and phenyl functional groups prepared by the synthesis method of the present invention can enable the E-51 resin to obtain lower dielectric constant and dielectric loss, which is crucial for its application in the fields of electronic communication and so on.

[0125] (4) Damp heat aging resistance property test: Immerse the pure epoxy resin and the epoxy composite containing the ladder polyhedral oligomeric silsesquioxane with amino and phenyl groups in a constant temperature water bath at 90 °C and boil for 105 days to conduct an accelerated damp heat aging test. After the aging is completed, conduct a tensile property test on it. The test results are asFigure 4 as shown

[0126] As Figure 4 It can be seen that after hydrothermal aging, specimens 2, 3, 4, and 5 have higher tensile strengths than the pure E-51 specimen. The tensile strength loss rate of the pure E-51 specimen is 41%, while the tensile strength loss rates of specimens 2, 3, 4, and 5 are 31%, 28%, 30%, and 30% respectively. This indicates that adding the ladder poly(silsesquioxane) containing amino and phenyl functional groups prepared by the synthesis method of the present invention can effectively improve the hydrothermal aging resistance of the E-51 resin and reduce the degree of tensile strength loss caused by hydrothermal aging.

[0127] The above are only the preferred embodiments of the present invention, and do not impose any form of limitation on the present invention. Although the present invention has been disclosed above with the preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to the above-mentioned technical content as equivalent embodiments with equivalent changes within the scope of the technical solution of the present invention. However, as long as it does not depart from the content of the technical solution of the present invention, any simple modification, equivalent change, and modification made to the above embodiments according to the technical essence of the present invention still fall within the scope of the present invention.

Claims

1. A ladder-type polyhedral oligomeric silsesquioxane containing amino and phenyl functional groups, characterized in that, It has a structure as shown in the general formula (I): Wherein, R is a functional group containing an amino group or a functional group containing a phenyl group; In the general formula (I), the functional group containing an amino group and the functional group containing a phenyl group exist simultaneously.

2. A ladder-type polyhedral oligomeric silsesquioxane containing amino and phenyl functional groups according to claim 1, characterized in that, R1 is selected from one of 3-aminopropyl, N-(2-aminoethyl)-3-aminopropyl, N-methyl-3-aminopropyl, and N-phenyl-3-aminopropyl; Preferably, R1 is selected from 3-aminopropyl or N-(2-aminoethyl)-3-aminopropyl.

3. A ladder-type polyhedral oligomeric silsesquioxane containing amino and phenyl functional groups according to claim 1 or 2, characterized in that, R2 is selected from one of phenyl, benzyl, 4-vinylphenyl, phenethyl, 3-phenylpropyl, 3-(phenylamino), and 6-phenylhexyl; Preferably, R2 is selected from phenyl.

4. A ladder-type polyhedral oligomeric silsesquioxane containing amino and phenyl functional groups according to any one of claims 1-3, characterized in that, n is an integer, 5 ≤ n ≤ 1000.

5. A ladder-type polyhedral oligomeric silsesquioxane containing amino and phenyl functional groups according to any one of claims 1-4, characterized in that, The content of amino groups in the general formula (I) is 2.0 - 4.0 wt%, preferably 2.5 - 3.8 wt%.

6. A preparation method of a ladder-type polyhedral oligomeric silsesquioxane containing amino and phenyl functional groups, characterized in that, It is used for preparing a ladder polyhedral oligomeric silsesquioxane containing amino and phenyl functional groups as described in any one of claims 1-5. The method includes the following steps: (1) Adding a silane precursor to a catalyst and a solvent for reaction to obtain a crude reaction product; (2) Post-treating the crude reaction product to obtain a ladder polyhedral oligomeric silsesquioxane containing amino and phenyl functional groups; The silane precursor is selected from a silane precursor containing an amino group and a silane precursor containing a phenyl group; Preferably, the silane precursor containing an amino group includes an amino group-containing siloxane and an amino group-containing chlorosilane; the silane precursor containing a phenyl group includes a phenyl group-containing siloxane and a phenyl group-containing chlorosilane; More preferably, the feeding mode of the silane precursor is that the silane precursor containing an amino group and the silane precursor containing a phenyl group are premixed and then fed together.

7. The preparation method of a ladder-type polyhedral oligomeric silsesquioxane containing amino and phenyl functional groups according to claim 6, characterized in that, The total molar concentration of the silane precursor containing an amino group and the silane precursor containing a phenyl group is 0.05 - 0.8 mo1 / L, preferably 0.1 - 0.5 mo1 / L.

8. The preparation method of a ladder-type poly(silsesquioxane) containing amino and phenyl functional groups according to claim 6 or 7, characterized in that, The molar ratio of the silane precursor containing an amino group to the silane precursor containing a phenyl group is (0.5 - 5):1, preferably (0.5 - 3):1, and more preferably 0.5:

1.

9. The preparation method of a ladder-type polyhedral oligomeric silsesquioxane containing amino and phenyl functional groups according to any one of claims 6-8, characterized in that, In step (1), the reaction temperature is 0 - 80 °C, preferably 25 - 60 °C; Preferably, the reaction time after the silane precursor is fed is 1 - 24 h, preferably 2 - 8 h; Preferably, in step (2), the post-treatment includes filtering the reaction system, washing it with deionized water multiple times, drying, pulverizing, washing it with ethyl acetate multiple times, and drying again.

10. Application of a ladder-type poly(silsesquioxane) containing amino and phenyl functional groups, characterized in that, Applying a ladder polyhedral oligomeric silsesquioxane containing amino and phenyl functional groups as described in any one of claims 1-5 in the modification treatment of polymer materials. The polymer materials include at least polyamide, polyethylene, polypropylene, polyvinyl chloride, epoxy resin, and bismaleimide resin; Preferably, the polymer materials are polyamide, epoxy resin, and bismaleimide resin.

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