Aminophenyl co-modified silicone oil as well as preparation method and application thereof

Abstract

The invention particularly relates to aminophenyl co-modified silicone oil as well as a preparation method and application thereof. The structural general formula of the aminophenyl co-modified silicone oil is as follows: (R1R2R3SiO1 / 2) a (R4R5SiO) b (R6R7SiO) c (R8R9SiO) d, wherein R1, R2, R3 and R6 are the same or different hydrogen groups or monovalent hydrocarbon groups without aliphatic unsaturated bonds; r4 and R5 are monovalent hydrocarbon groups or aromatic hydrocarbon groups which do not contain aliphatic unsaturated bonds and at least contain one aromatic hydrocarbon group; r7 is monovalent alkyl containing no less than one amino group; and R8 and R9 each represents a monovalent hydrocarbon group that does not contain an aliphatic unsaturated bond. The aminophenyl co-modified silicone oil is especially suitable for the application fields of organic silicon modified epoxy pouring sealants, structural adhesives and the like, can replace traditional amine catalysts, reduces the production cost, and improves the temperature resistance of the product.

Description

Technical Field

[0001] The present invention belongs to the technical field of silicone oil, and particularly relates to an amino phenyl co-modified silicone oil, a preparation method thereof, and an application thereof. Background Art

[0002] As a high-performance bonding material, epoxy resin structural adhesives are widely used in key fields such as aerospace composite material assembly, electronic component encapsulation, automotive lightweight structure bonding, and building structure reinforcement due to their excellent mechanical strength, chemical corrosion resistance, and dimensional stability. However, with the upgrade of industrial technology towards high temperature, high reliability, and environmental protection, traditional epoxy structural adhesive systems have gradually exposed technical bottlenecks in aspects such as curing process, heat resistance performance, and interfacial bonding strength. Currently, the mainstream curing system of epoxy structural adhesives relies on dicyandiamide (DICY) and its modified derivatives as latent catalysts. Although such catalysts can achieve curing through medium-temperature activation, their inherent defects severely limit the expansion of application scenarios and process upgrades. The compatibility between dicyandiamide and epoxy resin is relatively low, and it is easy to form local agglomerations in the resin matrix, resulting in uneven distribution of the crosslinking density of the curing network, causing problems such as stress concentration and increased brittleness of the adhesive layer. The measured volatility of the bonding strength can reach more than 15%. Moreover, dicyandiamide is listed as a potentially hazardous substance in the EU REACH regulation. Its synthesis process produces cyanide-containing wastewater, posing potential ecological toxicity risks and not conforming to the trend of green manufacturing. After adding amino silicone oil to epoxy adhesives, it can ensure that the epoxy adhesive provides lasting and effective bonding and protection in various extreme environments, extend the service life of the epoxy adhesive, and reduce maintenance costs.

[0003] Amino silicone oil belongs to special organosilicon compounds. Its structure combines the characteristics of organosilicon such as high and low temperature resistance, weather resistance, and low surface tension, as well as the reactivity of amino groups, and has broad application prospects in multiple industries such as textiles, electronics, coatings, and cosmetics. In the textile field, it can be used as a softener and antistatic agent; in the electronics field, due to its excellent insulation performance and temperature resistance characteristics, it is used for the encapsulation and insulation treatment of electronic components. In the field of epoxy adhesives, amino silicone oil, as a key chemical additive, can not only act as a crosslinking agent to promote the chemical reaction between various components in the coating, improve the structural stability of the coating, but also act as a modifier to optimize the basic performance of the coating, and can significantly improve the weather resistance of the coating.

[0004] At present, there have been various reports on the synthesis methods of amino silicone oil. Among them, the more common one is to carry out hydrosilylation reaction between amino silane and organic compounds containing unsaturated bonds, and then introduce amino functional groups. For example, the preparation of amino silicone oil by the addition reaction of polymethylhydrosiloxane and allylamine catalyzed by chloroplatinic acid described in patent CN202310020087.8, and the preparation of amino silicone oil with hydrogen-containing silicone oil, allyl epoxy polyether and polyetheramine as raw materials described in patent CN201911332014.2. These two methods have improved the reaction rate and product purity to a certain extent. However, the cost of platinum catalysts is high, and the difficulty of recycling and reuse is large, thus limiting the prospects of their industrial applications. And there are problems such as complex reaction processes, low product purity, cumbersome treatment and serious environmental pollution.

[0005] In response to the above problems, researchers have made improvement attempts. For example, Hangzhou Dadi Chemical Co., Ltd. uses raw materials such as hydroxyl-terminated silicone oil and N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane (KH-602) to synthesize amino-modified methylphenyl silicone oil by alkali catalysis. However, since the end-capping is still hydroxyl, the molecular weight of the silicone oil is easily affected by temperature during the polycondensation process, and it is difficult to obtain a stable and uniform molecular weight amino phenyl silicone oil. Some researchers have also tried to use physical means such as microwave radiation and ultrasonic waves to promote the reaction, or construct a microreactor to realize the continuity and automation of the reaction. However, the technical maturity and industrial application prospects of these new methods still need to be further verified.

[0006] Although there have been progress in toughening and modifying epoxy resins with organosilicon compounds such as hydroxyl silicone oil and amino silicone oil, there are obvious shortcomings in the technical effects. The traditional synthesis methods of amino silicone oil have high costs, harsh reaction conditions and many by-products, which limit their large-scale industrial applications. The reaction rate between the amino or hydroxyl groups in traditional silicone oil and epoxy groups is slow, and it depends on high-dose promoters or extended high-temperature curing times, and cannot replace the catalytic function of dicyandiamide. The glass transition temperature Tg of conventional epoxy structural adhesives is mostly in the range of 120-150 °C. Under long-term high temperature or thermal shock environments, the resin matrix is prone to chain segment relaxation and microcrack propagation, resulting in a significant attenuation of the bonding strength. Relying solely on amino-modified silicone oil to toughen and modify epoxy structural adhesives cannot further optimize their temperature resistance performance.

[0007] In addition, the production of amino-terminated agent raw materials in the industry is difficult, and the existing amino-terminated polysiloxane intermediates or amino-terminated phenylsiloxane intermediates are expensive. It is necessary to design and prepare an amino phenyl silicone oil synthesis process with low production cost and replaceable amino-terminated silicone oil. Although there are literature reports that amino(phenyl) silicone oil can be prepared by hydrolysis-polycondensation method, the yield is usually not high, the stability is poor, and the product is mostly in the form of emulsion, and it is difficult to form a stable single-phase system when blended with the epoxy resin system.

[0008] In summary, developing a cost-effective, easy-to-operate, and environmentally friendly synthesis process for amino phenyl silicone oil is of great significance for promoting its application in related industries. At present, there is no relatively mature preparation process for silicone oil co-modified with amino and phenyl groups. The present invention designs an amino phenyl co-modified silicone oil. By appropriately introducing phenyl chain segments onto the amino silicone oil chain, an amino phenyl co-modified silicone oil is prepared and applied to epoxy structural adhesives, which can achieve a catalytic effect while improving the adhesiveness and heat resistance of epoxy structural adhesives, and at the same time achieve the goals of high yield, low cost, and environmental friendliness, thus providing a more efficient, economical, and sustainable solution for industrial production.

[0009] Disclosing the information of this background art section is only intended to increase the understanding of the overall background of the present invention, and does not necessarily be regarded as an admission or imply in any form that this information constitutes the prior art already known to those of ordinary skill in the art. Summary of the Invention

[0010] The technical problem to be solved by the present invention is to provide an amino phenyl co-modified silicone oil. By adding phenyl silane monomers or phenyl siloxanes and amino silanes, phenyl chain segments and amino side chains are introduced into the molecular chain of polysiloxane, and the ratio of amino to phenyl content is designed and controlled to enhance the rigidity of the molecular chain and significantly improve the thermal stability of the silicone oil. It can act as a curing agent in epoxy structural adhesives, effectively improve the adhesiveness and high and low temperature impact resistance of epoxy structural adhesives, and at the same time achieve a catalytic effect.

[0011] The technical solution adopted by the present invention to solve the above problems is as follows:

[0012] An amino phenyl co-modified silicone oil, whose structural general formula is as follows:

[0013] (R 1 R 2 R 3 SiO 1 / 2 ) a (R 4 R 5 SiO) b (R 6 R 7 SiO) c (R 8 R 9 SiO) d ;

[0014] Wherein, R 1 , R 2 , R 3 and R 6 are the same or different hydrogen groups or monovalent hydrocarbon groups without aliphatic unsaturated bonds; R 4 and R 5is a monovalent hydrocarbon group or aromatic hydrocarbon group without aliphatic unsaturated bonds and contains at least one aromatic hydrocarbon group; R 7 is a monovalent hydrocarbon group containing at least one amino group; R 8 and R 9 are monovalent hydrocarbon groups without aliphatic unsaturated bonds.

[0015] Preferably, the amino equivalent of the amino phenyl co-modified silicone oil is 240-800 g / eq, the refractive index is 1.48-1.52, and the dynamic viscosity at 25 °C is 800-2000 mPa·s.

[0016] Furthermore, the amino phenyl co-modified silicone oil comprises the following preparation raw materials by weight: 1.5-82 parts of a silane end-capping agent, 30-175 parts of an amino silane, 80-140 parts of a phenyl silane monomer or phenyl siloxane, 9-50 parts of a hydrocarbyl silane monomer or hydrocarbyl siloxane, 0.9-2.4 parts of a basic catalyst, and 4-43 parts of deionized water.

[0017] In the above technical solution, the silane end-capping agent can improve the molecular weight uniformity of the silicone oil; the amino silane can provide side-chain amino groups; the phenyl silane monomer or phenyl siloxane can provide phenyl groups; the hydrocarbyl silane monomer or hydrocarbyl siloxane can reduce steric hindrance.

[0018] Preferably, the structural general formula of the silane end-capping agent is:

[0019] R 1 R 2 R 3 SiOR 4 ;

[0020] wherein, R 1 、R 2 and R 3 are the same or different hydrogen groups or monovalent hydrocarbon groups without aliphatic unsaturated bonds, and R 4 is a hydrogen atom or a monovalent hydrocarbon group or a silyl group without aliphatic unsaturated bonds.

[0021] Preferably, the silane end-capping agent comprises one or two of a silane with a monofunctional siloxane structure, a siloxane with a monofunctional siloxane structure, and a silanol with a monofunctional siloxane structure.

[0022] Exemplarily, the silane end-capping agent includes, but is not limited to, one or two of hexamethyldisiloxane, methoxytrimethylsilane, ethoxytrimethylsilane, trimethoxy(octyl)silane, isopropoxytrimethylsilane, octamethyltrisiloxane, trimethylsilanol, triethylsilanol, dimethylphenylsilanol, and triphenylsilanol.

[0023] Preferably, the aminosilane includes a silane having at least one amino group or amine group; the amine group includes at least one of a primary amine and a secondary amine.

[0024] Exemplarily, the aminosilane includes, but is not limited to, at least one of γ-aminopropylmethyldiethoxysilane, γ-aminopropylmethyldimethoxysilane, N-cyclohexyl-γ-aminopropylmethyldimethoxysilane, N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane, and 3-(N,N-dimethylaminopropyl)aminopropylmethyldimethoxy.

[0025] Preferably, the phenylsilane monomer includes a silane having at least one aromatic group; the phenylsiloxane includes a siloxane having at least one aromatic group.

[0026] Exemplarily, the phenylsilane monomer includes, but is not limited to, diphenyldimethoxysilane, diphenyldiethoxysilane, methylphenyldimethoxysilane, methylphenyldiethoxysilane; the phenylsiloxane is at least one of 2,4,6-trimethyl-2,4,6-triphenylcyclotrisiloxane, tetramethyltetraphenylcyclotetrasiloxane, pentamethylpentaphenylcyclopentasiloxane, and a mixed cyclic body of methylphenylsiloxane.

[0027] Preferably, the structural general formula of the hydrocarbylsilane monomer or hydrocarbylsiloxane is:

[0028] R 1 R 2 Si(O 1 / 2 R 3 )(O 1 / 2 R 4 );

[0029] Wherein, R 1 、R 2 are the same or different hydrogen groups or monovalent hydrocarbon groups without aliphatic unsaturated bonds, and R 3 、R 4 are monovalent hydrocarbon groups without aliphatic unsaturated bonds or silyl groups containing siloxane bonds.

[0030] Exemplarily, the hydrocarbylsilane monomer or hydrocarbylsiloxane includes, but is not limited to, at least one of dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldimethoxysilane, octamethylcyclotetrasiloxane (D 4 ), decamethylcyclopentasiloxane (D 5 ), and a dimethylcyclosiloxane mixture (DMC).

[0031] Preferably, the basic catalyst includes at least one of an organic base and an inorganic base.

[0032] Exemplarily, the basic catalyst includes, but is not limited to, at least one of tetramethylammonium hydroxide (TMAH) and its pentahydrate, potassium hydroxide, and sodium hydroxide.

[0033] The present invention provides the preparation method of the above-mentioned amino-phenyl co-modified silicone oil, comprising the following steps:

[0034] S1. Add a silane endblocker, an amino-silane monomer, a phenyl-silane monomer or phenyl-siloxane, an alkyl-silane monomer or alkyl-siloxane, a basic catalyst, and deionized water into a reactor, introduce nitrogen, stir at 60°C to 80°C, and carry out a condensation reflux reaction for 1 to 1.2 h;

[0035] S2. Remove nitrogen, continue to heat up to 95°C to 105°C and keep warm until the system is basically transparent; then carry out vacuum distillation under the conditions of -0.090 to -0.1 MPa and 95°C to 105°C until the liquid is transparent and no low-boiling substances are distilled out;

[0036] S3. After removing the vacuum distillation device, perform any one of the following operations:

[0037] (i) Open the reactor, heat up to 135°C to 145°C and stir until there is no white foam on the liquid surface;

[0038] or (ii) Maintain the closed state, and after the liquid cools to room temperature, add acetic acid to adjust the pH to 7.0 to 8.0;

[0039] Finally, the obtained transparent viscous substance is the amino-phenyl co-modified silicone oil.

[0040] The present invention also provides an application of the above-mentioned amino-phenyl co-modified silicone oil in the preparation of an epoxy adhesive.

[0041] The present invention has the following beneficial effects:

[0042] By adding a phenyl-silane monomer or phenyl-siloxane and an amino-silane, the present invention introduces phenyl linkages and amino branches into the molecular chain of polysiloxane, and designs and controls the content ratio of amino groups and phenyl groups, enhancing the rigidity of the molecular chain, significantly improving the thermal stability of the silicone oil. It can act as a curing agent in an epoxy structural adhesive, effectively improving the adhesiveness and high and low temperature impact resistance of the epoxy structural adhesive, and simultaneously achieving a catalytic effect.

[0043] The amino-phenyl co-modified silicone oil prepared by the present invention is a colorless transparent or light yellow transparent viscous substance, without pungent odor, with high transparency, and can be applied to a high refractive index epoxy structural adhesive system. It has high compatibility with epoxy-modified silicone oil and silicone resin, can replace the dicyandiamide-based latent curing agent used in traditional epoxy adhesives, and solve the problem of poor compatibility between traditional dicyandiamide-based curing agents and silicone components. At the same time, it can be applied to the catalysis of epoxy adhesives, completely abandoning traditional toxic dicyandiamide-based catalysts, and reducing the volatile organic compound (VOC) emissions by more than 70%.

[0044] The preparation method of the present invention designs the molecular chain structure, controls the proportion of amino and phenyl contents, and optimizes the reaction conditions, designing an amino-phenyl silicone oil synthesis process for end-amino silicone oil with low preparation cost, high yield, environmental friendliness and replaceability, providing a more efficient, economical and sustainable solution for industrial production to meet the needs of industrial production; it has important application and replacement value in the field of silicone-modified epoxy resins. The obtained amino-phenyl co-modified silicone oil realizes the replacement of traditional end-amino (phenyl) silicone oil, reduces the production cost, improves the heat resistance of the product, and has excellent storage stability, and can be stored for more than 300 days. Brief Description of the Drawings

[0045] Figure 1 : Ultraviolet-visible absorption spectrogram of the amino-phenyl co-modified silicone oil prepared in Examples 1 to 5;

[0046] Figure 2 : FTIR test result diagram of the amino-phenyl co-modified silicone oil prepared in Example 2;

[0047] Figure 3 : The 1 H NMR test result diagram of the amino-phenyl co-modified silicone oil prepared in Example 2;

[0048] Figure 4 : The 13 C NMR test result diagram of the amino-phenyl co-modified silicone oil prepared in Example 2. Detailed Embodiments

[0049] To make the technical problems, technical solutions and technical advantages to be solved by the present invention clearer, the following will be described in detail with specific examples. However, the protection scope of the present invention is not limited to the following specific examples. The described embodiments are only a part of the embodiments of the present invention, not all of the embodiments, and even less a limitation of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0050] Unless otherwise defined, all technical terms used hereinafter have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present invention.

[0051] Unless otherwise specifically stated, various raw materials, reagents, instruments, equipment, etc. used in the present invention can be obtained through market purchase or can be prepared by existing methods.

[0052] Example 1:

[0053] S1. Add hexamethyldisiloxane (1.62 g, 0.01 mol), N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane (137.58 g, 0.67 mol), methylphenyldimethoxysilane (109.37 g, 0.600 mol), octamethylcyclotetrasiloxane (9.67 g, 0.0326 mol), tetramethylammonium hydroxide (1.29 g) and deionized water (36.48 g) into a 1 L four-necked flask, introduce nitrogen, and mechanically stir at 75 °C for condensation reflux reaction for 1 h;

[0054] S2. Remove nitrogen, raise the temperature to 95 °C and continue the reaction for 4 h; then carry out vacuum distillation under the conditions of -0.1 MPa and 95 °C until the liquid is transparent and no low-boiling substances are distilled out;

[0055] S3. After removing the vacuum distillation device, open the reactor, raise the temperature to 135 °C - 145 °C and stir the reaction until there is no white foam on the liquid surface to obtain amino-phenyl co-modified silicone oil.

[0056] Total weight of the product obtained in Example 1: 184.77 g, yield: 92.41%.

[0057] Example 2:

[0058] S1. Add hexamethyldisiloxane (81.20 g, 0.500 mol), N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane (51.60 g, 0.25 mol), methylphenyldimethoxysilane (136.72 g, 0.75 mol), octamethylcyclotetrasiloxane (26.64 g, 0.09 mol), tetramethylammonium hydroxide (1.48 g) and deionized water (28.80 g) into a 1 L four-necked flask, introduce nitrogen (99.9%), and mechanically stir at 75 °C for condensation reflux reaction for 1 h;

[0059] S2. Remove nitrogen, raise the temperature to 95 °C and continue the reaction for 4 h; then carry out vacuum distillation under the conditions of -0.1 MPa and 95 °C until the liquid is transparent and no low-boiling substances are distilled out;

[0060] S3. After removing the vacuum distillation device, open the reactor and raise the temperature to 135 °C to 145 °C for stirring reaction until there is no white foam on the liquid surface, thus obtaining the amino phenyl co-modified silicone oil.

[0061] Total weight of the product obtained in Example 2: 229.19 g, yield: 91.62%.

[0062] Example 3:

[0063] S1. Add hexamethyldisiloxane (33.10 g, 0.204 mol), N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane (30.95 g, 0.15 mol), methylphenyldimethoxysilane (127.60 g, 0.70 mol), octamethylcyclotetrasiloxane (48.10 g, 0.65 mol), tetramethylammonium hydroxide (0.96 g) and deionized water (42.91 g) into a 1 L four-necked flask.

[0064] S2. Remove nitrogen and raise the temperature to 95 °C for continuous reaction for 4 h; then carry out vacuum distillation under the conditions of -0.090 MPa and 95 °C until the liquid is transparent and no low-boiling substances are distilled out.

[0065] S3. After the vacuum distillation is completed, remove the distillation device, maintain the flask in a closed state, and add acetic acid to adjust the pH to 7.0 - 8.0 after the liquid cools to room temperature, thus obtaining the amino phenyl co-modified silicone oil.

[0066] Total weight of the product obtained in Example 3: 191.22 g, yield: 92.13%.

[0067] Example 4:

[0068] S1. Add hexamethyldisiloxane (32.48 g, 0.20 mol), γ-aminopropylmethyldiethoxysilane (57.40 g, 0.30 mol), methylphenyldimethoxysilane (116.67 g, 0.64 mol), dimethylcyclosiloxane mixture DMC (45.15 g), tetramethylammonium hydroxide (2.01 g) and deionized water (27.07 g) into a 1 L four-necked flask, introduce nitrogen (99.9%), and carry out mechanical stirring at 75 °C for condensation reflux reaction for 1 h.

[0069] S2. Remove nitrogen and raise the temperature to 95 °C for continuous reaction for 4 h; then carry out vacuum distillation under the conditions of -0.1 MPa and 95 °C until the liquid is transparent and no low-boiling substances are distilled out.

[0070] S3. After removing the vacuum distillation device, open the reactor and raise the temperature to 135 °C to 145 °C for stirring reaction until there is no white foam on the liquid surface, thus obtaining the amino phenyl co-modified silicone oil.

[0071] Total weight of the product obtained in Example 4: 167.91 g, yield: 83.95%.

[0072] Example 5:

[0073] S1. Add hexamethyldisiloxane (1.62 g, 0.01 mol), γ-aminopropylmethyldiethoxysilane (172.21 g, 0.90 mol), methylphenylsiloxane mixed cyclic oligomers (81.78 g, 0.60 mol), dimethylcyclosiloxane mixture DMC (11.09 g), tetramethylammonium hydroxide (2.37 g) and deionized water (4.2 g) into a 1 L four-necked flask. Introduce nitrogen (99.9%), stir mechanically at 75 °C, and carry out a condensation reflux reaction for 1 h;

[0074] S2. Remove nitrogen, raise the temperature to 95 °C and continue the reaction for 4 h; then carry out vacuum distillation under the conditions of -0.1 MPa and 95 °C until the liquid is transparent and no low-boiling substances are distilled out;

[0075] S3. After removing the vacuum distillation device, open the reactor, raise the temperature to 135 °C - 145 °C and stir the reaction until there is no white foam on the liquid surface to obtain the amino-phenyl co-modified silicone oil.

[0076] Total weight of the product obtained in Example 5: 166.31 g, yield: 83.15%.

[0077] The characteristic structures of the amino-phenyl co-modified silicone oils prepared in the above Examples 1 - 3 are as follows:

[0078]

[0079] The characteristic structures of the amino-phenyl co-modified silicone oils prepared in the above Examples 4 - 5 are as follows:

[0080]

[0081] The amino-phenyl co-modified silicone oils prepared in Examples 1 - 5 were tested as follows:

[0082] (1) Fourier transform infrared spectroscopy (FTIR):

[0083] Using a Nicolet iS50 Fourier transform infrared spectrometer manufactured by Thermo Fisher Scientific, Germany, by the KBr tablet method, the scanning wavelength range is 4000 - 600 cm -1 , the resolution is 4 cm -1 , and the scanning times are 32 times for the test.

[0084] (2) Proton nuclear magnetic resonance ( 1 H-NMR) and carbon-13 nuclear magnetic resonance ( 13 C-NMR):

[0085] The Bruker AVANCE III 400MHz Superconducting Fourier nuclear magnetic resonance spectrometer made in Switzerland was used, and the measurement condition was room temperature. The solvent was deuterated chloroform (CDCl 3 ). And the 1 1H NMR internal standard method was adopted to test the amino content of the prepared amino phenyl co-modified silicone oil. The specific method was as follows: at room temperature, 1,4-dioxane was used as the internal standard substance, and CDCl 3 was used as the solvent. A certain amount of the sample and 1,4-dioxane were weighed and mixed in CDCl 3 , and after ultrasonic treatment for 20 min, the test was carried out, and the amino content was calculated. Then the nuclear magnetic carbon spectrum was measured by changing the scanning mode.

[0086] (3) Density: It was tested according to GB / T 13354-1992.

[0087] (4) Viscosity: The dynamic viscosity value at 25 °C was tested according to GB / T 10247-1988.

[0088] (5) Refractive index: It was tested according to GB / T 6488-2008.

[0089] (6) Visible light transmittance: It was tested by using the UV2450 ultraviolet-visible spectrophotometer of Shimadzu Corporation in Japan according to the ASTM D 1003-13 standard.

[0090] (7) Storage stability: According to GB / T7123.2-2002, with viscosity as the index, the storage period was obtained, and the storage stability was compared by the length of the storage period.

[0091] The ultraviolet-visible absorption spectra of the amino phenyl co-modified silicone oils prepared in Examples 1 to 5 were as Figure 1 shown: The amino phenyl co-modified silicone oils in Examples 1 to 5 all had high transparency, and their refractive indices were all between 1.48 and 1.52, and they had good compatible transparency with substances such as conventional phenyl silicone resins.

[0092] The FTIR test results of the amino phenyl co-modified silicone oil prepared in Example 2 were as Figure 2 shown: The characteristic absorption peak of the stretching vibration of C-H on the benzene ring was at 3070 cm -1 ; the characteristic absorption peaks of the stretching vibration of C-H on methyl and methylene were at 2960 cm -1 and 2923 cm -1 ; the stretching vibration absorption peak of -NH- and -NH 2 on KH-602 was at 1592 cm -1 , and the stretching vibration absorption peak at 1429 cm -1For KH-602, the bending vibration absorption peaks of -NH- and -NH 2 are at 1257 cm -1 , 839 cm -1 , 792 cm -1 ; the characteristic bending vibration absorption peak of Si-CH 3 is at 1013 cm -1 ; the characteristic stretching vibration absorption peak of the silicon-oxygen chain is at 696 cm -1 ; 696 cm

[0093] The 1 H NMR test results of the amino-phenyl co-modified silicone oil prepared in Example 2 are as follows Figure 3 : 1 H NMR: The peak at 7.31 ppm is the deuterated chloroform peak, and the peak at 3.70 ppm is 1,4-dioxane; the doublets at 7.34 ppm and 7.52 ppm are phenyl peaks, the peak at 0.07 ppm is the silicon methyl peak, the peak at 0.38 ppm is the methylene hydrogen atom peak closer to the silicon atom between the secondary amine and the silicon atom, the peak at 1.29 ppm is the second methylene hydrogen atom peak between the secondary amine and the silicon atom, the peak at 2.41 ppm is the hydrogen atom peak on the α-H and β-C of the primary amine, and the peak at 2.72 ppm is the hydrogen atom peak on the α-H and two α-C of the secondary amine.

[0094] The 13 C NMR test results of the amino-phenyl co-modified silicone oil prepared in Example 2 are as follows Figure 4 : 13 C NMR: The quartet at 129.51 ppm is the benzene ring carbon atom peak, the doublets at 52.87 ppm and 50.49 ppm are the two α-C of the secondary amino group, the α-C of the primary amino group is at 41.92 ppm, the β-C on the side of the secondary amino group closer to the silicon atom is at 23.51 ppm, the carbon atom closest to the silicon atom near the secondary amino group is at 14.82 ppm, and the multiplet near -0.12 ppm is the carbon atom of the silicon methyl group.

[0095] The physical property characterization results of the amino-phenyl co-modified silicone oils prepared in Examples 1-5 are shown in Table 1.

[0096] Table 1:

[0097]

[0098]

[0099] Examples 6-10

[0100] The amino phenyl silicone oils described in Examples 1 to 5 were applied to the preparation of epoxy structural adhesives. The amounts of each component used in the preparation of epoxy structural adhesives in Examples 6 to 10 are shown in Table 2 (unit: g).

[0101] Table 2:

[0102]

[0103] In Examples 6 to 10, the above components were respectively mixed and cured at a high temperature of 180 °C for 20 min.

[0104] Comparative Example 1 provided a commercially available product, specifically ShinEtsu X-22-9409 modified silicone oil.

[0105] Comparative Example 2 provided a commercially available product, specifically Silok - 3262F2.

[0106] Comparative Example 3 provided a commercially available product, specifically Huiya New Materials DICY-06 one-component dicyandiamide curing agent.

[0107] The commercially available products provided in Comparative Examples 1 to 3 were used to prepare a kind of high-temperature resistant structural adhesive. The amounts of each component used in the preparation of high-temperature resistant structural adhesives in Comparative Examples 1 to 3 are shown in Table 3 (unit: g).

[0108] Table 3:

[0109]

[0110] In Comparative Examples 1 to 3, the above components were respectively mixed and cured at a high temperature of 180 °C for 20 min.

[0111] The epoxy structural adhesives prepared in Examples 6 to 10 and the structural adhesives prepared in Comparative Examples 1 to 3 were tested as follows:

[0112] (1) Voltage resistance test: After the adhesive was coated on the surface of a 0.4 mm thick copper sheet at 90 μm and cured, a Blue Science 2672X voltage resistance tester was used to test its maximum breakdown current. The insulation requirement: for any AC or DC voltage, the leakage current ≤ 5 mA and the insulation time ≥ 5 s.

[0113] (2) Shrinkage rate: Tested according to ISO 3521 standard.

[0114] (3) Pull-out force test: The adhesive was coated on the surface of a cylindrical pure copper fixture with φ = 1.5 cm. After the two fixtures were butted and cured, the pull-out force was calculated according to pull-out force = maximum force / area.

[0115] (4) Bending test: Bend the copper sheet coated with the cured adhesive at a 90° angle according to the requirement that the size of the bent part is about R5, observe whether the bent part is intact (no cracks, no peeling), and test the maximum breakdown voltage of the bent part according to the above-mentioned withstand voltage test standard.

[0116] (5) High and low temperature shock test: After subjecting to a low temperature shock of -40°C for 15 minutes and then a high temperature shock of 285°C for 15 minutes, with a total of 30 minutes as one cycle, conduct the high and low temperature shock test on the copper sheet coated with the cured adhesive and cycle 12 times, and then test the adhesive pull-out force test, bending test, and withstand voltage test according to the above standards.

[0117] The insulation test results of Examples 6 to 10 and Comparative Examples 1 to 3 after high temperature curing at 180°C are shown in Table 4.

[0118] Table 4:

[0119]

[0120] It can be tested that after curing, Examples 6 to 10 all have good insulation properties. The maximum AC breakdown voltage on the flat surface ≥ 1.97 kV, DC ≥ 2.48 kV; the AC ≥ 1.32 kV, DC ≥ 1.56 kV at the bent part.

[0121] The insulation test results of Examples 6 to 10 and Comparative Examples 1 to 3 after 12 cycles of high and low temperature shock at -40°C * 15 min to 285°C * 15 min are shown in Table 5. Among them, the bent parts of Comparative Example 2 and Comparative Example 3 cracked after 6 and 4 cycles of high and low temperature shock respectively, so there are no corresponding AC and DC test values.

[0122] Table 5:

[0123]

[0124] The test shows that after high and low temperature shock, the 5 examples can still maintain the maximum AC breakdown voltage on the flat surface ≥ 1.72 kV, DC ≥ 2.04 kV; and the AC ≥ 1.01 kV, DC ≥ 1.47 kV at the bent part, proving that these 5 examples have insulation effects in extreme temperature environments. The flexibility of Comparative Examples 1 to 3 decreased significantly after 12 shock cycles and the maximum breakdown current value at the bent part decreased significantly. The reason is that there are no branched amino groups in the polysiloxane chain of Comparative Example 1, resulting in a decrease in the crosslinking density of the structural adhesive, while the molecular chain of Comparative Example 2 does not contain high-temperature-resistant groups such as phenyl groups and is prone to chain breakage in high-temperature environments, thereby leading to a decrease in adhesion; in addition, Comparative Example 3 uses a traditional dicyandiamide curing agent for crosslinking, which is prone to causing the glue surface to crack. Therefore, using the catalysts of Examples 1 to 5 of the present invention to cure epoxy structural adhesives can effectively improve the flexibility of the product.

[0125] The test results of the drawing force and shrinkage rate of Examples 6 to 10 and Comparative Examples 1 to 3 are shown in Table 6.

[0126] Table 6:

[0127]

[0128] After high-temperature curing, the shrinkage rates of Examples 6 to 10 were all < 2.5%, and they had good bonding strength, which could effectively act on the bonding between metal surfaces; after 12 high-low temperature cycle impacts, they could still maintain a relatively high drawing force, and the maximum value was 243.10 kg / cm 2 , which could effectively meet the high bonding strength requirements in small areas.

[0129] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0130] In addition, it should be noted that, in the case of no contradiction, the various specific technical features described in the above specific embodiments can be combined in any suitable manner. To avoid unnecessary repetition, the present invention will not separately describe various possible combination methods.

[0131] Furthermore, any combination can be made between various different embodiments of the present invention, as long as it does not violate the idea of the present invention, and it should also be regarded as the content disclosed by the present invention.

Claims

1. An aminophenyl co-modified silicone oil, characterized in that: Its general structure is as follows: (R1R2R3SiO 1 / 2 ) a (R4R5SiO) b (R6R7SiO) c (R8R9SiO) d ; Among them, R1, R2, R3 and R6 are the same or different hydrogen groups or monovalent hydrocarbon groups without aliphatic unsaturated bonds; R4 and R5 are monovalent hydrocarbon groups without aliphatic unsaturated bonds or aromatic hydrocarbon groups and contain at least one aromatic hydrocarbon group; R7 is a monovalent hydrocarbon group containing not less than one amino group; R8 and R9 are monovalent hydrocarbon groups without aliphatic unsaturated bonds.

2. The aminophenyl co-modified silicone oil according to claim 1, characterized in that The aminophenyl co-modified silicone oil comprises the following raw materials in parts by weight: 1.5 to 82 parts of silane end-capping agent, 30 to 175 parts of aminosilane, 80 to 140 parts of phenylsilane monomer or phenylsiloxane, 9 to 50 parts of hydrocarbon silane monomer or hydrocarbon siloxane, 0.9 to 2.4 parts of alkaline catalyst, and 4 to 43 parts of deionized water.

3. The aminophenyl co-modified silicone oil according to claim 2, characterized in that: The general structural formula of the silane capping agent is: R1R2R3SiOR4; Among them, R1, R2 and R3 are the same or different hydrogen groups or monovalent hydrocarbon groups without aliphatic unsaturated bonds, and R4 is a hydrogen atom or a monovalent hydrocarbon group without aliphatic unsaturated bonds or a silane group.

4. The aminophenyl co-modified silicone oil according to claim 2, characterized in that: The silane capping agent includes one or two of silane having a monofunctional silicon-oxygen structure, siloxane having a monofunctional silicon-oxygen structure, and silanol having a monofunctional silicon-oxygen structure.

5. The aminophenyl co-modified silicone oil according to claim 2, characterized in that: The aminosilane includes a silane having at least one amino group or amine group; the amine group includes at least one of a primary amine and a secondary amine.

6. The aminophenyl co-modified silicone oil according to claim 2, characterized in that: The phenylsilane monomer includes a silane having at least one aromatic group; and the phenylsiloxane includes a siloxane having at least one aromatic group.

7. The aminophenyl co-modified silicone oil according to claim 2, characterized in that: The general structural formula of the hydrocarbyl silane monomer or hydrocarbyl siloxane is: R1R2Si(O 1 / 2 R3)(O 1 / 2 R4); Among them, R1 and R2 are the same or different hydrogen groups or monovalent hydrocarbon groups without aliphatic unsaturated bonds, and R3 and R4 are monovalent hydrocarbon groups without aliphatic unsaturated bonds or silane groups containing silicon-oxygen bonds.

8. The aminophenyl co-modified silicone oil according to claim 2, characterized in that: The alkaline catalyst includes at least one of an organic base and an inorganic base.

9. A method for preparing the aminophenyl co-modified silicone oil according to any one of claims 1 to 8, characterized in that: The steps include: S1. Add a silane capping agent, an aminosilane monomer, a phenylsilane monomer or a phenylsiloxane, a hydrocarbylsilane monomer or a hydrocarbylsiloxane, a basic catalyst and deionized water into a reactor, introduce nitrogen gas, stir at 60°C to 80°C, and condense and reflux for 1 to 1.2 hours; S2. Remove nitrogen, continue to heat to 95 ℃ ~ 105 ℃ and keep warm until the system is basically transparent; then distill under reduced pressure at -0.090 ~ -0.1MPa, 95 ℃ ~ 105 ℃ until the liquid is transparent and no low-boiling substances are distilled; S3. After removing the vacuum distillation apparatus, perform any of the following operations: (i) opening the reactor, heating it to 135°C to 145°C and stirring until there is no white foam on the liquid surface; or (ii) maintaining the sealed state, adding acetic acid to adjust the pH to 7.0-8.0 after the liquid is cooled to room temperature; The transparent viscous substance finally obtained is aminophenyl co-modified silicone oil.

10. Use of the aminophenyl co-modified silicone oil according to any one of claims 1 to 9 in the preparation of epoxy adhesives.

Images