Adamantane-modified silane coupling agent, one-component dealcoholized silicone rubber and preparation method thereof

Abstract

The application discloses adamantane-modified silane coupling agent, one-component dealcoholization type silicone rubber and a preparation method thereof. The adamantane-modified silane coupling agent is obtained by sequentially reacting adamantanol with tetramethyldivinyl disilazane and a modifier; and the structural formula of the modifier is as follows. The crosslinking agent in the one-component dealcoholization type silicone rubber is the adamantane-modified silane coupling agent. The one-component dealcoholization type silicone rubber prepared by using the adamantane-modified silane coupling agent as the crosslinking agent has high tensile strength and elongation at break, and has good comprehensive mechanical properties.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of silicone rubber, in particular to dealcoholized silicone rubber, and more particularly to adamantane-modified silane coupling agent, one-component dealcoholized silicone rubber and preparation method thereof. BACKGROUND

[0002] As an important classification of coupling agent, silane coupling agent is an organosilicon compound with two or more different reactive groups, which can form chemical bonding between organic and inorganic materials as a reactive "bridge". At present, one of the important uses of silane coupling agent is as a crosslinking agent, which can form a three-dimensional network structure of siloxane as a "bridge" to obtain room temperature vulcanized silicone rubber. New crosslinking agents can impart room temperature vulcanized silicone rubber with more excellent performance or special functionality by introducing different functional groups and molecular structure design. There are more than one hundred kinds of silane coupling agents with known structures, and the prepared silicone rubber has been widely used in various fields such as construction, medical treatment, electronics and electrical appliances, photovoltaic, battery, energy storage, aerospace, etc.

[0003] With the development of science and technology, better expectations are put forward for the advanced indicators of functional materials. The commonly used crosslinking agents for dealcoholized RTV-1 silicone rubber, such as vinyltrimethoxysilane, methyltrimethoxysilane, and tetramethoxysilane, have limited improvement on the mechanical properties of silicone rubber, which is obviously not suitable for new requirements. In recent years, the newly introduced phenyltrimethoxysilane coupling agent improves the elongation of silicone rubber while improving its heat resistance, but reduces the tensile strength of silicone rubber; the introduced bis-silane coupling agent 1,2-bis(trimethoxysilyl)ethane has two silane structures in the same molecular structure, and there are six alkoxy groups on one molecule, which can form a higher crosslinking density on the surface of inorganic materials. The silanol formed after hydrolysis is more acidic than the silanol formed by ordinary silane coupling agents, so it can form a more stable covalent bond with the hydroxyl group on the surface of metal and inorganic materials, and is not easy to hydrolyze, thereby improving the water resistance. In addition, there are alkoxy silane oligomers, which have the characteristics of low odor, low volatility, and high flash point. By increasing the crosslinking points on the coupling agent, the curing speed and mechanical strength can be improved. However, these silane coupling agents that increase the crosslinking density of the silicone rubber network by increasing the crosslinking points will reduce the tensile rate of the silicone rubber.

[0004] Therefore, it is urgent to further research and develop a new type of coupling agent to simultaneously improve the tensile strength and elongation of silicone rubber. SUMMARY

[0005] Therefore, the purpose of the present application is to provide a crosslinking agent that can simultaneously improve the tensile strength and elongation of silicone rubber, and to provide a one-component dealcoholized silicone rubber that has both high tensile strength and elongation.

[0006] In order to achieve the above object, the present application comprises the following technical solutions.

[0007] In a first aspect, the present application provides adamantane-modified silane coupling agent, having the following structure:

[0008]

[0009] Each X is independently selected from -H, -OH and -R;

[0010] Each R is independently selected from:

[0011] n is 0 or an integer greater than 0;

[0012] Y1 is -OCH3 or -OCH2CH3, and Y2 is -OCH3, -OCH2CH3 or -CH3.

[0013] The adamantane-modified silane coupling agent of the present application is obtained by sequentially reacting adamantanol with tetramethyldivinyl disilazane and a modifier;

[0014] The modifier has the following structure:

[0015] n is 0 or an integer greater than 0;

[0016] Y1 is -OCH3 or -OCH2CH3, and Y2 is -OCH3, -OCH2CH3 or -CH3.

[0017] In a second aspect, the present application provides a preparation method of the adamantane-modified silane coupling agent, comprising the following steps:

[0018] (1) reacting the adamantanol with tetramethyldivinyl disilazane to obtain an intermediate product;

[0019] (2) reacting the intermediate product with the modifier in the presence of a platinum-gold catalyst to obtain the adamantane-modified silane coupling agent.

[0020] In a third aspect, the present application provides application of the adamantane-modified silane coupling agent as a crosslinking agent in preparation of one-component dealcoholized silicone rubber.

[0021] In a fourth aspect, the present application provides one-component dealcoholized silicone rubber, wherein the crosslinking agent is the adamantane-modified silane coupling agent of the present application.

[0022] For example, the one-component dealcoholized silicone rubber is prepared from raw materials comprising the following components by weight:

[0023]

[0024] In a fifth aspect, the present application provides a preparation method of the one-component dealcoholized silicone rubber, comprising the following steps: mixing the base polymer, the filler and the plasticizer uniformly, then heating and dehydrating, adding the crosslinking agent, the coupling agent and the catalyst after cooling, and mixing uniformly to obtain the one-component dealcoholized silicone rubber.

[0025] The present application has the following beneficial effects:

[0026] The present application designs and synthesizes a kind of adamantyl-based silane coupling agent, and uses it as a crosslinking agent to prepare a one-component dealcoholized room temperature vulcanized silicone rubber. The introduction of the stereoscopic adamantane cage structure in the siloxane network can increase the rigid fulcrum and hydrogen bonding points of the siloxane network. At the same time, the hollow adamantane cage structure has a large specific surface area, which can improve the mechanical strength of the silicone rubber. In addition, the adamantyl group has a large steric hindrance, which can significantly weaken the effect of intermolecular forces and increase the activity space between polymer molecular chains, thereby reducing the cohesion of the silicone rubber and improving the elongation of the silicone rubber.

[0027] The one-component dealcoholized silicone rubber prepared by using the adamantane-modified silane coupling agent as a crosslinking agent has high tensile strength and elongation at break, and good comprehensive mechanical properties. In addition, the synergistic effect of the reasonable chain length and structure can further improve the tensile strength and elongation of the obtained silicone rubber, and the silicone rubber has a reasonable surface drying time and good construction performance, and has excellent comprehensive performance.

[0028] The preparation method of the adamantane-modified silane coupling agent is simple and reproducible, and can be applied to the design and preparation of silicone rubber without special process, thereby improving the comprehensive mechanical properties of the silicone rubber and facilitating industrialization. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 IR spectra of the intermediate product (a) obtained in step (1) and the adamantane-modified silane coupling agent (b) obtained in step (2) in Example 1. DETAILED DESCRIPTION

[0030] The technical solutions of the present application will be further described below through specific examples. Those skilled in the art should understand that the examples are only used to help understand the present application and should not be regarded as a specific limitation of the present application.

[0031] Unless otherwise defined, all technical and scientific terms used in the present application have the same meaning as understood by those skilled in the art to which the present application belongs. The terms used in the specification of the present application are only for the purpose of describing the specific examples and should not be used to limit the present application.

[0032] The terms "comprising" and "having" and any variations thereof herein are intended to cover a non-exclusive inclusion. For example, a process, method, article, or apparatus that comprises a list of steps or modules are not necessarily limited to those listed steps or modules, but can include additional steps or modules, not necessarily listed, or can include steps or modules inherent to such process, method, article, or apparatus.

[0033] "Multiple" mentioned in the present application refers to two or more. "And / or", which describes the association relationship of the associated objects, means that there can be three relationships, for example, A and / or B can represent the following three cases: A exists alone, A and B exist together, and B exists alone. The character " / " generally represents that the associated objects before and after it are in an "or" relationship.

[0034] Some embodiments of the present application relate to adamantane-modified silane coupling agents, which have the following structure:

[0035]

[0036] Each X is independently selected from -H, -OH, and -R;

[0037] Each R is independently selected from:

[0038] n is 0 or an integer greater than 0;

[0039] Y1 is -OCH3 or -OCH2CH3, and Y2 is -OCH3, -OCH2CH3, or -CH3.

[0040] In some preferred embodiments, each X is hydrogen.

[0041] In some preferred embodiments, one X is hydrogen and two Xs are R.

[0042] In some preferred embodiments, two Xs are hydrogen and one X is R.

[0043] In some preferred embodiments, three Xs are R.

[0044] In some preferred embodiments, n is an integer between 0 and 50, preferably an integer between 5 and 30, and more preferably an integer between 8 and 15. For example, n can be 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, etc.

[0045] In some preferred embodiments, Y1 is -OCH3 and Y2 is -OCH3.

[0046] In some preferred embodiments, Y1 is -OCH3 and Y2 is -CH3.

[0047] The adamantane-modified silane coupling agent of the present application is obtained by sequentially reacting adamantanol with tetramethyldivinyl disilazane and a modifier;

[0048] The structural formula of the modifier is:

[0049] wherein n is 0 or an integer greater than 0;

[0050] Y1 is -OCH3 or -OCH2CH3, and Y2 is -OCH3, -OCH2CH3 or -CH3.

[0051] In some preferred embodiments, the molar ratio of the hydroxyl group in the adamantanol to tetramethyldivinyl disilazane and the modifier is 1:(0.5-20):(0.8-2), preferably 1:(1-5):(1-1.5).

[0052] In some preferred embodiments, the adamantanol is selected from the group consisting of one or more of 1-adamantanol, adamantane-1,3-diol, adamantane-1,3,5-triol, adamantane-1,3,5,7-tetraol and 1-adamantanemethanol.

[0053] In some preferred embodiments, n is an integer between 0 and 50, preferably an integer between 5 and 30, and more preferably an integer between 8 and 15. For example, n can be 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, etc.

[0054] In some preferred embodiments, Y1 is -OCH3 and Y2 is -OCH3.

[0055] In some preferred embodiments, Y1 is -OCH3 and Y2 is -CH3.

[0056] In some embodiments of the present application, a preparation method of the adamantane-modified silane coupling agent is also provided, which comprises the following steps:

[0057] (1) reacting the adamantanol with tetramethyldivinyl disilazane to obtain an intermediate product;

[0058] (2) reacting the intermediate product with the modifier in the presence of a platinum-gold catalyst to obtain the adamantane-modified silane coupling agent.

[0059] In some preferred embodiments, the platinum catalyst is selected from at least one of platinum-vinyl complex and platinum-alkyne complex, preferably bis(1,3-divinyl-1,1,3,3-tetramethyldisiloxane)platinum(0) and / or trimethyl(methylcyclopentadienyl)platinum(IV).

[0060] In some embodiments, the reaction in step (1) and step (2) is carried out in an organic solvent, preferably ethyl acetate.

[0061] In some preferred embodiments, the reaction in step (1) is carried out at a temperature of 40-90℃ for 0.5-8h.

[0062] In some preferred embodiments, the reaction in step (1) is carried out at a temperature of 70-90℃ for 1-3h.

[0063] In some preferred embodiments, the reaction in step (2) is carried out at a temperature of 10-100℃ for 0.5-5h.

[0064] In some preferred embodiments, the reaction in step (2) is carried out at a temperature of 60-80℃ for 1-3h.

[0065] In some embodiments of the present application, the adamantane-modified silane coupling agent is also used as a crosslinking agent in the preparation of one-component dealcoholized silicone rubber.

[0066] In some embodiments of the present application, one-component dealcoholized silicone rubber is also provided, wherein the crosslinking agent is the adamantane-modified silane coupling agent of the present application.

[0067] In some embodiments, the one-component dealcoholized silicone rubber is prepared from raw materials comprising the following components by weight:

[0068]

[0069] In some preferred embodiments, the one-component dealcoholized silicone rubber is prepared from raw materials comprising the following components by weight:

[0070]

[0071] In some preferred embodiments, the one-component dealcoholized silicone rubber is prepared from raw materials comprising the following components by weight:

[0072]

[0073]

[0074] In some preferred embodiments, the base polymer is a hydroxyl-terminated polydimethylsiloxane or an alkoxyl-terminated polydimethylsiloxane, and the viscosity of the base polymer at 23°C is preferably 1500 mP s to 80000 mP s, more preferably 10000 mP s to 80000 mP s, more preferably 10000 mP s to 50000 mP s, more preferably 18000 mP s to 22000 mP s.

[0075] In some preferred embodiments, the filler is selected from one or more combinations of fumed silica, nano calcium carbonate, titanium dioxide, kaolin, diatomite, silica powder, mica, and barium sulfate.

[0076] In some embodiments, the filler is a combination of nano calcium carbonate and R812 fumed silica, and the mass ratio of the nano calcium carbonate to the R812 fumed silica is preferably 5-8:1, more preferably 6-7:1.

[0077] In some preferred embodiments, the plasticizer is selected from at least one of dimethyl silicone oil, methoxyl silicone oil, MDT silicone oil, and hydroxyl silicone oil, and the viscosity of the plasticizer at 23°C is preferably 50 mP s to 1000 mP s, more preferably 300 mP s to 500 mP s.

[0078] In some preferred embodiments, the coupling agent is selected from one or more combinations of 3-aminopropyltrimethoxysilane, N-cyclohexyl-γ-aminopropylmethyldimethoxysilane, bis(3-trimethoxysilylpropyl)amine, amino silane oligomer, cyanopropyltriethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, and 3-ureidopropyltriethoxysilane.

[0079] In some preferred embodiments, the catalyst is one or more combinations of an organic tin catalyst and a phthalate catalyst.

[0080] In some preferred embodiments, the organic tin catalyst is selected from at least one of dibutyltin dilaurate, dibutyltin diacetate, dimethyltin bis(neodecanoate), and bis(acetylacetonyl) dibutyltin.

[0081] In some preferred embodiments, the phthalate catalyst is selected from at least one of tetra-n-butyl titanate, polytetra-n-butyl titanate, 2-ethylhexyloxy titanate, 1,3-propanediolytitanium bis(ethyl acetoacetate) (acetylacetone), and diisopropyl titanate bis(ethyl acetoacetate).

[0082] In some embodiments of the present invention, a method for preparing a one-component de-alcoholized silicone rubber is also involved, comprising the following steps: mixing the base polymer, filler, and plasticizer evenly, heating to dehydrate, cooling, adding the crosslinking agent, coupling agent, and catalyst, mixing evenly, and obtaining the one-component de-alcoholized silicone rubber.

[0083] The following are specific examples.

[0084] Unless otherwise specified, "parts" in the following embodiments refer to parts by weight.

[0085] The general formula of the modifier in the following examples is as follows:

[0086]

[0087] Example 1

[0088] 1. Preparation of adamantane-modified silane coupling agents

[0089]

[0090] (1) Dissolve 0.1 mol adamantane-1-ol in 30 ml ethyl acetate, add 0.15 mol tetramethyldivinyldisilazane while stirring, and reflux at 80 °C for 2 h while stirring thoroughly. Remove the solvent and unreacted silazane by vacuum distillation; wash the filtrate with deionized water until neutral and dry for later use.

[0091] (2) The product obtained in step (1) was redissolved in 50 ml of ethyl acetate. After it was fully dissolved, 0.11 mol of modifier (n = 10, Y1 is -OCH3 and Y2 is -OCH3) was added and dispersed evenly. Under stirring, 0.0001 mol of bis(1,3-divinyl-1,1,3,3-tetramethyldisiloxane)platinum (0) was added. The temperature was raised to 70 °C and the reaction was stirred for 2 h. The solvent was removed under reduced pressure to obtain a colorless or light yellow liquid, which is the adamantane-modified silane coupling agent.

[0092] The IR spectrum of the intermediate product obtained in step (1) is shown below. Figure 1 As shown in a, at 1630cm -1 The point is the deformation vibration of the carbon-carbon double bond C=C; the IR spectrum of the adamantane-modified silane coupling agent obtained in step (2) is as follows. Figure 1 As shown in b: 1630cm -1 The deformation vibration peak of the carbon-carbon double bond C=C disappears at 1270m. -1 The point represents the CO stretching vibration on the methoxy group.

[0093] 2. Preparation of one-component dealcoholized silicone rubber

[0094] Hydroxyl-terminated polydimethylsiloxane with viscosity of 80000 mP·s at 23℃ 60 parts, hydroxyl-terminated polydimethylsiloxane with viscosity of 20000 mP·s at 23℃ 40 parts, nano calcium carbonate CCS-23 powder 120 parts, dimethyl silane with viscosity of 350 mP·s at 23℃ 5 parts were mixed uniformly and heated to 150℃ for 3 hours of dehydration, then cooled to add adamantane modified silane coupling agent 5 parts, N-cyclohexyl-γ-aminopropyl methyl dimethoxy silane 0.5 parts, bis(3-trimethoxysilylpropyl)amine 0.5 parts and 1,3-propylene glycol titanium bis(acetylacetate ethyl ester) (acetylacetone) 3 parts, mixed uniformly, and discharged to obtain one-component dealcoholized silicone rubber.

[0095] Example 2

[0096] 1, Preparation of adamantane modified silane coupling agent

[0097]

[0098] The difference from example 1 is that adamantane-1,3-diol is used instead of adamantane-1-al, and the addition amount is 0.05 mol. The other raw materials and amounts and preparation methods are the same as those of example 1.

[0099] 2, Preparation of one-component dealcoholized silicone rubber

[0100] The difference from example 1 is that the adamantane modified silane coupling agent prepared in example 2 is used to replace the adamantane modified silane coupling agent in example 1, and the other raw materials and amounts and preparation methods are the same as those of example 1.

[0101] Example 3

[0102] 1, Preparation of adamantane modified silane coupling agent

[0103]

[0104] The difference from example 1 is that adamantane-1,3,5,7-tetraol is used instead of adamantane-1-al, and the addition amount is 0.02 mol. The other raw materials and amounts and preparation methods are the same as those of example 1.

[0105] 2, Preparation of one-component dealcoholized silicone rubber

[0106] The difference from example 1 is that the adamantane modified silane coupling agent prepared in example 3 is used to replace the adamantane modified silane coupling agent in example 1, and the other raw materials and amounts and preparation methods are the same as those of example 1.

[0107] Example 4

[0108] 1, Preparation of adamantane modified silane coupling agent

[0109] The difference from Example 1 is that n = 30 in the modifier, Y1 is -OCH3, and Y2 is -OCH3. The other raw materials and amounts and the preparation method are the same as in Example 1.

[0110] 2. Preparation of one-component dealcoholized silicone rubber

[0111] The difference from Example 1 is that adamantane-modified silane coupling agent prepared in Example 4 is used to replace the adamantane-modified silane coupling agent in Example 1, and the other raw materials and amounts and the preparation method are the same as in Example 1.

[0112] Example 5

[0113] 1. Preparation of adamantane-modified silane coupling agent

[0114] The difference from Example 1 is that n = 10 in the modifier, Y1 is -OCH3, and Y2 is -CH3. The other raw materials and amounts and the preparation method are the same as in Example 1.

[0115] 2. Preparation of one-component dealcoholized silicone rubber

[0116] The difference from Example 1 is that adamantane-modified silane coupling agent prepared in Example 6 is used to replace the adamantane-modified silane coupling agent in Example 1, and the other raw materials and amounts and the preparation method are the same as in Example 1.

[0117] Example 6

[0118] 1. Preparation of adamantane-modified silane coupling agent

[0119] The difference from Example 1 is that an equal amount of trimethyl(methylcyclopentadienyl) platinum (IV) is used to replace bis(1,3-divinyl-1,1,3,3-tetramethyldisiloxane) platinum. The other raw materials and amounts and the preparation method are the same as in Example 1.

[0120] 2. Preparation of one-component dealcoholized silicone rubber

[0121] The difference from Example 1 is that adamantane-modified silane coupling agent prepared in Example 7 is used to replace the adamantane-modified silane coupling agent in Example 1, and the other raw materials and amounts and the preparation method are the same as in Example 1.

[0122] Example 7

[0123] 1. Preparation of adamantane-modified silane coupling agent is the same as in Example 1.

[0124] 2. Preparation of one-component dealcoholized silicone rubber

[0125] The difference between this example and example 1 is that the amount of adamantane-modified silane coupling agent is 15 parts, and the other raw materials and amounts and the preparation method are the same as in example 1.

[0126] Example 8

[0127] 1. Preparation of adamantane-modified silane coupling agent as in example 1.

[0128] 2. Preparation of one-component dealcoholized silicone rubber

[0129] Mix 100 parts of alkoxy-terminated polydimethylsiloxane with a viscosity of 20000 mP·s at 23℃, 80 parts of nano calcium carbonate CCS-25 powder, and 10 parts of dimethyl silicone oil with a viscosity of 350 mP·s at 23℃, and then dehydrate at 150℃ for 3h after uniform mixing. After cooling, add 12 parts of R812 fumed silica and disperse uniformly, then add 4 parts of adamantane-modified silane coupling agent, 0.5 parts of γ-methacryloyloxypropyltrimethoxysilane, and 0.8 parts of 1,3-propanediol titanium bis(acetylacetic acid ethyl ester) (acetylacetone), mix uniformly, and discharge to obtain one-component dealcoholized silicone rubber.

[0130] Comparative Example 1

[0131] The one-component dealcoholized silicone rubber provided in this comparative example differs from example 1 in that equal parts by weight of methyltrimethoxysilane are used instead of adamantane-modified silane coupling agent, and the other raw materials and amounts and the preparation method are the same as in example 1.

[0132] Comparative Example 2

[0133] The one-component dealcoholized silicone rubber provided in this comparative example differs from example 1 in that equal parts by weight of phenyltrimethoxysilane are used instead of adamantane-modified silane coupling agent, and the other raw materials and amounts and the preparation method are the same as in example 1.

[0134] Comparative Example 3

[0135] The one-component dealcoholized silicone rubber provided in this comparative example differs from example 1 in that equal parts by weight of methyltrimethoxysilane oligomer are used instead of adamantane-modified silane coupling agent, and the other raw materials and amounts and the preparation method are the same as in example 1.

[0136] Performance testing

[0137] The one-component dealcoholized silicone rubber prepared in the above examples and comparative examples is subjected to sample preparation and sample curing under the same conditions, and then the following performance tests are performed:

[0138] Surface dry time: the surface dry time is determined according to the GB / T 13477.5-2002 B method of finger touch;

[0139] Tensile strength and elongation at break: The tensile strength and elongation at break of the vulcanized for 168 h at room temperature were determined according to GB / T 528-2009.

[0140] The results are shown in Table 1.

[0141] Table 1

[0142]

[0143]

[0144] As can be seen from Table 1, the crosslinking reaction is greatly affected by the molecular shielding effect. The stronger the steric hindrance effect provided by the crosslinking agent group, the more the crosslinking points are shielded, which will lead to the decrease of the strength and the increase of the elongation of the silicone rubber. The tensile strength and elongation at break of the silicone rubber obtained in Comparative Example 1 are not ideal, because the conventional methyltrimethoxysilane is used as the crosslinking agent. In Comparative Example 2, the methyltrimethoxysilane in Comparative Example 1 is replaced by phenyltrimethoxysilane. The phenyl group has a larger steric hindrance than the methyl group, and the shielding effect of the crosslinking reaction is stronger, which leads to a decrease in the crosslinking points, a significant decrease in the strength and a significant increase in the elongation of the obtained silicone rubber. In Comparative Example 3, the methyltrimethoxysilane in Comparative Example 1 is replaced by a methylmethoxysilane oligomer. The local crosslinking density around the crosslinking points is increased, and the crosslinking network is formed faster, which shortens the surface drying time of the obtained silicone rubber and increases the tensile strength, but the crosslinking density is uneven, which leads to a decrease in the elongation. It can be seen that the existing silane coupling agent is difficult to simultaneously improve the tensile strength and elongation at break of the silicone rubber.

[0145] In Examples 1-8, the adamantane-modified silane coupling agent prepared in the present application is used to replace the methyltrimethoxysilane in Comparative Example 1, and the tensile strength and elongation at break of the obtained silicone rubber are significantly improved. This may be because the adamantyl group has a large steric hindrance, and the internal hollow structure is stable, so the shielding effect is strong, which can improve the elongation. At the same time, the multiple active hydrogens on the adamantane can form more hydrogen bonds with polysiloxane. The adamantyl group has a rigid cage structure and a large specific surface area, which can play a reinforcing effect similar to that of silica. Therefore, under the combined action of various factors, the tensile strength and elongation of the obtained silicone rubber can be simultaneously improved.

[0146] The number of hydroxyl groups in adamantane used in Examples 1-3 is different, i.e. the number of siloxy groups in the adamantane-modified silane coupling agent is different, as can be seen from the data in the table. The increase in crosslinking points provided by the adamantane-modified silane coupling agent shortens the time for forming a crosslinking network, which is manifested in that the surface dry time of the obtained silicone rubber becomes shorter as the crosslinking points increase, and the tensile strength improves as the crosslinking points increase. It is found that, thanks to the stereocage structure of adamantane, the reactive siloxane groups are distributed stereoscopically around adamantane, unlike the linear methyltrimethoxysilane oligomer (Comparative Example 3), as the crosslinking density increases, the elongation of the silicone rubber does not decrease, but rather is further significantly improved. The silicone rubber of Example 3 has a relatively higher tensile strength and the highest elongation at break, and has the lowest surface dry time, and has the best comprehensive performance.

[0147] Example 4 increases the flexible siloxane chain segment between adamantane and alkoxy compared to Example 1, which weakens the intermolecular force, and the activity space between polymer molecular chains is larger, the tensile strength decreases and the elongation at break slightly improves.

[0148] Example 5 replaces the trimethoxysilane-terminated modifier with a dimethoxyl-terminated modifier compared to Example 1, the hydrolytic activity of the end group is significantly reduced, the crosslinking density is reduced, the surface dry time is significantly increased, which will affect the construction efficiency; the crosslinking degree is reduced, the modulus is reduced, which leads to an increase in the elongation at break; at the same time, the steric hindrance is reduced, the crosslinking is more complete, and the tensile strength is also slightly improved.

[0149] Example 6 replaces the catalyst for catalyzing the vinyl addition reaction compared to Example 1, which has little effect on the final performance of the obtained silicone rubber.

[0150] Example 7 increases the amount of adamantane-modified silane coupling agent to 15 parts compared to Example 1, the tensile strength is further improved, but the elongation at break decreases, and the surface dry time increases.

[0151] Example 8 uses a combination of nano calcium carbonate and fumed silica as fillers, which is used in combination with the adamantane-modified silane coupling agent, and the three have a synergistic reinforcing effect, which can further significantly improve the tensile strength of the obtained silicone rubber, and also further improve the elongation, but the surface dry time will increase.

[0152] The technical features of the above-described examples can be combined in any manner. In order to make the description concise, not all possible combinations of the technical features in the above-described examples are described, however, as long as the combinations of the technical features do not exist contradictory, they should be considered as the scope of the present description.

[0153] The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent. It should be noted that for ordinary skilled persons in the art, without departing from the concept of the present application, several modifications and improvements can be made, which are within the scope of protection of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A silane coupling agent modified with adamantane, characterized in that, It has the following structure: Each X is independently selected from: -H, -OH, and -R; Each R is selected independently from: n is an integer that is 0 or greater than 0; Y1 is -OCH3 or -OCH2CH3, and Y2 is -OCH3, -OCH2CH3, or -CH3.

2. The adamantane-modified silane coupling agent according to claim 1, characterized in that, All X are hydrogen; or, one X is hydrogen and two X are R; or, two X are hydrogen and one X is R; or, all three X are R.

3. The adamantane-modified silane coupling agent according to claim 1 or 2, characterized in that, n is an integer between 0 and 50; And / or, Y1 is -OCH3, Y2 is -OCH3 or -CH3.

4. The adamantane-modified silane coupling agent according to claim 3, characterized in that, n is an integer between 5 and 30.

5. The adamantane-modified silane coupling agent according to claim 4, characterized in that, n is an integer between 8 and 15.

6. A silane coupling agent modified with adamantane, characterized in that, It is obtained by reacting adamantane alcohol with tetramethyldivinyldisilazane and a modifier in sequence according to the following steps; (1) The adamantanol reacts with tetramethyldivinyldisilazane to give an intermediate product; (2) The intermediate product reacts with the modifier under the action of a platinum catalyst to obtain the adamantane-modified silane coupling agent; The structural formula of the modifier is: Where n is a zero or a greater than zero integer; Y1 is -OCH3 or -OCH2CH3, and Y2 is -OCH3, -OCH2CH3, or -CH3.

7. The adamantane-modified silane coupling agent according to claim 6, characterized in that, The molar ratio of the hydroxyl group in the adamantanol to tetramethyldivinyldisilazane and the modifier is 1:(0.5-20):(0.8-2); And / or, the adamantanol is selected from one or more combinations of 1-adamantanol, adamantane-1,3-diol, adamantane-1,3,5-triol, adamantane-1,3,5,7-tetraol and 1-adamantanethanol; And / or, n is an integer between 0 and 50; And / or, Y1 is -OCH3, Y2 is -OCH3 or -CH3.

8. The adamantane-modified silane coupling agent according to claim 7, characterized in that, The molar ratio of the hydroxyl group in the adamantanol to tetramethyldivinyldisilazane and the modifier is 1:(1-5):(1-1.5).

9. The adamantane-modified silane coupling agent according to claim 7, characterized in that, n is an integer between 5 and 30.

10. The adamantane-modified silane coupling agent according to claim 9, characterized in that, n is an integer between 8 and 15.

11. A method for preparing an adamantane-modified silane coupling agent according to any one of claims 1-10, characterized in that, Includes the following steps: (1) Adamantanol reacts with tetramethyldivinyldisilazane to give an intermediate product; (2) The intermediate product reacts with a modifier under the action of a platinum catalyst to obtain the adamantane-modified silane coupling agent. The structural formula of the modifier is: Where n is a zero or a greater than zero integer; Y1 is -OCH3 or -OCH2CH3, and Y2 is -OCH3, -OCH2CH3, or -CH3.

12. The method for preparing the adamantane-modified silane coupling agent according to claim 11, characterized in that, The platinum catalyst is selected from at least one of platinum-vinyl complexes and platinum-alkynyl complexes.

13. The method for preparing the adamantane-modified silane coupling agent according to claim 12, characterized in that, The platinum catalyst is bis(1,3-divinyl-1,1,3,3-tetramethyldisiloxane)platinum (0) and / or trimethyl(methylcyclopentadienyl)platinum (IV).

14. The method for preparing the adamantane-modified silane coupling agent according to claim 11, characterized in that, The reaction in step (1) is carried out at a temperature of 40℃ to 90℃ for a time of 0.5h to 8h.

15. The method for preparing the adamantane-modified silane coupling agent according to claim 11, characterized in that, The reaction in step (2) is carried out at a temperature of 10℃ to 100℃ for a time of 0.5h to 5h.

16. The use of the adamantane-modified silane coupling agent according to any one of claims 1-10 as a crosslinking agent in the preparation of one-component alcohol-free silicone rubber.

17. A one-component dealcoholized silicone rubber, characterized in that, The crosslinking agent is the adamantane-modified silane coupling agent as described in any one of claims 1-10.

18. The one-component dealcoholized silicone rubber according to claim 17, characterized in that, The one-component dealcoholized silicone rubber is prepared from raw materials comprising the following components, by weight:

19. The single-component dealcoholized silicone rubber according to claim 18, characterized in that, By weight, the single-component alcohol-free silicone rubber is prepared from raw materials comprising the following components:

20. The single-component dealcoholized silicone rubber according to claim 19, characterized in that, By weight, the single-component alcohol-free silicone rubber is prepared from raw materials comprising the following components:

21. The one-component dealcoholized silicone rubber according to any one of claims 18-20, characterized in that, The base polymer is either hydroxyl-terminated polydimethylsiloxane or alkoxy-terminated polydimethylsiloxane.

22. The one-component dealcoholized silicone rubber according to any one of claims 18-20, characterized in that, The viscosity of the base polymer at 23°C is 1500 mP·s to 80000 mP·s.

23. The single-component alcohol-de-alcoholized silicone rubber according to claim 22, characterized in that, The viscosity of the base polymer at 23°C is 10,000 mP·s to 80,000 mP·s.

24. The single-component alcohol-free silicone rubber according to claim 23, characterized in that, The viscosity of the base polymer at 23°C is 10,000 mP·s to 50,000 mP·s.

25. The single-component alcohol-free silicone rubber according to claim 24, characterized in that, The viscosity of the base polymer at 23°C is 18000 mP·s to 22000 mP·s.

26. The one-component dealcoholized silicone rubber according to any one of claims 18-20, characterized in that, The filler is selected from one or more combinations of fumed silica, nano-calcium carbonate, titanium dioxide, kaolin, diatomaceous earth, silica powder, mica and barium sulfate.

27. The one-component dealcoholized silicone rubber according to any one of claims 18-20, characterized in that, The plasticizer is selected from at least one of dimethyl silicone oil, methoxy silicone oil, MDT silicone oil, and hydroxyl silicone oil.

28. The one-component dealcoholized silicone rubber according to any one of claims 18-20, characterized in that, The viscosity of the plasticizer at 23°C is 50 mP·s to 1000 mP·s.

29. The single-component dealcoholized silicone rubber according to claim 28, characterized in that, The viscosity of the plasticizer at 23°C is 300 mP·s to 500 mP·s.

30. The one-component dealcoholized silicone rubber according to any one of claims 18-20, characterized in that, The coupling agent is selected from one or more combinations of 3-aminopropyltrimethoxysilane, N-cyclohexyl-γ-aminopropylmethyldimethoxysilane, bis(3-trimethoxysilylpropyl)amine, aminosilane oligomers, γ-methacryloyloxypropyltrimethoxysilane, and 3-ureopropyltriethoxysilane.

31. The one-component dealcoholized silicone rubber according to any one of claims 18-20, characterized in that, The catalyst is one or more of organotin catalysts and phthalate catalysts.

32. The single-component alcohol-free silicone rubber according to claim 31, characterized in that, The organotin catalyst is selected from at least one of dibutyltin dilaurate, dibutyltin diacetate, dimethyltin dinecapate, and diacetylacetonate dibutyltin.

33. The single-component alcohol-free silicone rubber according to claim 31, characterized in that, The phthalate catalyst is selected from at least one of tetrabutyl titanate, polytetrabutyl titanate, 1,3-propanedioxytitanium bis(ethyl acetoacetate) (acetylacetone), and bis(ethyl acetoacetate) diisopropyl titanate.

34. A method for preparing a one-component dealcoholized silicone rubber according to any one of claims 18-33, characterized in that, The process includes the following steps: mixing the base polymer, filler, and plasticizer evenly, heating to dehydrate, cooling, adding the crosslinking agent, coupling agent, and catalyst, mixing evenly, and obtaining the single-component de-alcoholized silicone rubber.

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