Platinum complex as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of addition type liquid silicone rubber, and discloses a platinum complex as well as a preparation method and application thereof. The molecular structural formula of the platinum complex comprises at least one of the structural formulas shown in the formula (I) and the formula (II): # imgabs0. The multi-ligand synergistically coordinated platinum complex has low activity at room temperature, the stability and room temperature storage time of addition type liquid silicone rubber can be greatly prolonged, and the platinum complex can be stably stored at room temperature for more than 3 months at most; and the catalytic activity is quickly recovered at the temperature higher than 100 DEG C, so that the addition type liquid silicone rubber can be vulcanized within 10 minutes. The platinum complex disclosed by the invention has the characteristics of simple preparation process, good catalytic performance, high stability and the like, and is a high-performance platinum catalyst capable of greatly prolonging the stability and room-temperature storage time of the addition type liquid silicone rubber and catalyzing rapid vulcanization of the addition type liquid silicone rubber at a high temperature.

Description

Technical Field

[0001] The present invention belongs to the technical field of addition-cured liquid silicone rubber, and particularly relates to a platinum complex, a preparation method thereof and an application thereof. Background Art

[0002] Organosilicon compounds refer to compounds containing Si-C bonds and having at least one organic substituent directly connected to a silicon atom. Organosilicon materials made from organosilicon compounds have a wide variety of varieties and excellent properties, and have been widely used in industrial and agricultural production, emerging technologies, national defense industry, medical and health care, and people's daily lives. Organosilicon products have become one of the fastest-growing varieties in new chemical materials. Among them, the transition metal-catalyzed hydrosilylation reaction is a synthetic method for organosilicon compounds with step economy and atom economy. Currently, the catalysts used in hydrosilylation reactions are mainly compounds of transition metal elements in Group VIII B of the periodic table, such as platinum, palladium, nickel, and rhodium. Among them, platinum catalysts have the highest catalytic activity and are the most widely used. Most platinum catalysts have extremely high activity at room temperature. Among them, Karstedt catalyst is a highly active catalyst for hydrosilylation, and it is also the most common hydrosilylation catalyst on the market today.

[0003] Karstedt catalyst has extremely high activity at room temperature. However, industrial applications often require a sufficient long operation time. Usually, a certain amount of inhibitor is added according to the usage situation. The inhibitor can reduce the low-temperature catalytic activity of the platinum catalyst and extend the reaction time, while the catalyst quickly resumes its activity at high temperatures. Therefore, in the field of addition-cured liquid silicone rubber, the catalyst usually needs to be stored separately from the inhibitor and the cross-linking agent. Generally, it consists of two components, A and B. Before use, it needs to be mixed and stirred according to a certain ratio to cure (vulcanize) the two-component liquid silicone rubber. Therefore, the two-component liquid silicone rubber can only be mixed before use, but the operation time after mixing is relatively short, which is inconvenient to use. Moreover, if the proportion control is improper during mixing, the product yield will decrease. In view of the deficiencies of two-component liquid silicone rubber, one-component liquid silicone rubber has emerged.

[0004] One-component liquid silicone rubber can be taken and used at any time, which is beneficial to reducing the process complexity and product yield. As a catalyst for one-component liquid silicone rubber products, it is required to have low activity at room temperature to extend the room-temperature storage time, and can quickly resume catalytic activity at high temperatures to achieve rapid cross-linking. Currently, there is still a lack of high-performance one-component liquid silicone rubber in China. Currently, there are two ideas for developing a catalytic system suitable for one-component liquid silicone rubber.

[0005] One approach is to develop catalysts with low activity at room temperature. For example, Guoqiao Lai et al. developed an acetylated platinum complex as a catalyst for one-component silicone rubber, which improved the room-temperature storage time of addition-cured one-component liquid silicone rubber to a certain extent, allowing it to be stably stored for 15 days [Appl. Organometal. Chem. 2012, 26, 461–466]. However, the storage time of the one-component liquid silicone rubber based on this catalyst is still relatively short. Based on the procurement and storage requirements of enterprises, a longer storage time is expected.

[0006] Another approach is to add a large amount of inhibitors. For example, the Chinese patent application with the publication number CN 112662181 A discloses a one-component platinum vulcanizing agent and its preparation method. This one-component platinum vulcanizing agent is prepared by mixing a Karstedt platinum catalyst, an inhibitor, an organic amine, a hydrogen-containing silicone oil, and silica according to a certain formula. It can complete vulcanization within 2 minutes at high temperature, but its room-temperature storage time is only 5 days, which is too short and not conducive to enterprise procurement and storage. In addition, there are certain defects in such a catalytic-inhibitor system. If a longer operation time at room temperature is to be achieved, a large amount of inhibitor must be added, which correspondingly leads to a significant extension of the vulcanization time of the one-component liquid silicone rubber at high temperature, reducing production efficiency and increasing energy consumption.

[0007] The above-mentioned one-component catalyst systems generally have problems such as too long high-temperature vulcanization time or too short room-temperature storage time, and have many limitations in actual use. Therefore, developing new catalysts and preparing high-performance liquid silicone rubber is of great significance for the domestic silicone industry. Summary of the Invention

[0008] To overcome the above-mentioned disadvantages and deficiencies of the prior art, the primary object of the present invention is to provide a platinum complex.

[0009] The platinum complex of the present invention is characterized by low activity at room temperature and rapid recovery of activity at high temperature. When used as a catalyst in addition-cured liquid silicone rubber, its property of being stably stored at room temperature for a long time greatly extends the stability and room-temperature storage time of the addition-cured liquid silicone rubber, and the room-temperature storage can exceed 90 days. At the same time, when the temperature is higher than 100 °C, the catalytic activity can be quickly restored, enabling the addition-cured liquid silicone rubber to quickly complete vulcanization, and the T90 vulcanization time can be less than 10 minutes.

[0010] Another object of the present invention is to provide a preparation method of the above-mentioned platinum complex.

[0011] Another object of the present invention is to provide the application of the above-mentioned platinum complex in the field of addition-cured liquid silicone rubber.

[0012] The objects of the present invention are achieved by the following solutions:

[0013] A platinum complex, the molecular structural formula of which includes at least one of the structural formulas shown in formula (I) and formula (II):

[0014]

[0015] Wherein, L 1 is tetramethyldivinyldisiloxane, and L 2 are respectively organophosphorus compounds that are the same or different, and L 3 is an alkynol compound; x, y, and z are coordination numbers, x is 0 or 1; y is a natural number from 1 to 4, and z is a natural number from 1 to 20.

[0016] In the structure of the platinum complex of the present invention, zero-valent platinum coordinates with multiple ligands simultaneously to obtain a multi-ligand synergistic coordination platinum complex. Among them, there is a competitive relationship when the ligand coordinates with zero-valent platinum. For example, zero-valent platinum can coordinate with the ethylene unit of the L 1 ligand and the phosphorus of the L 2 ligand. When the amount of the L 2 ligand is sufficient, zero-valent platinum no longer coordinates with the ethylene unit of the L 1 ligand and only coordinates with the phosphorus of the L 2 ligand; similarly, zero-valent platinum can coordinate with the ethylene unit of the L 1 ligand, the phosphorus of the L 2 ligand, and the alkynyl of the L 3 ligand. When the amount of the L 2 ligand or the L 3 ligand is sufficient, zero-valent platinum no longer coordinates with the ethylene unit of the L 1 ligand and only coordinates with the L 2 ligand and the L 3 ligand.

[0017] Furthermore, the organophosphorus compound includes but is not limited to at least one of tris(4-methoxyphenyl)phosphine, tris(4-tert-butylphenyl) phosphite, tris(4-butoxyphenyl) phosphite, bis(2,4-di-tert-butylphenol)pentaerythritol diphosphite, tris(2-tert-butylphenyl) phosphite, bis(2-tert-butylphenyl)-(2-nonylphenyl) phosphite, (2-tert-butylphenyl)-bis(2-nonylphenyl) phosphite, tris(2-nonylphenyl) phosphite, tris(2,4-di-tert-butylphenyl) phosphite, phenyl diisooctyl phosphite, triethyl phosphite, triisooctyl phosphite, triisodecyl phosphite, bis(isodecyl alcohol)pentaerythritol diphosphite, diphenyl isooctyl phosphite, tris(trifluoroethyl) phosphite, tris(hexafluoroisopropyl) phosphite, tris(trimethylsilyl) phosphite, tris(allyl) phosphite, tris(propynyl) phosphite, etc.

[0018] Specifically, the organophosphorus compounds include but are not limited to at least one of the following formulas (1) to (20):

[0019]

[0020] Furthermore, the alkynol compounds include but are not limited to at least one of cyclohexyl alkynol, cyclopentyl alkynol, 1-cyclohexylprop-2-yn-1-ol, 3,5-dimethyl-1-hexyn-3-ol, 2-methyl-5-octyn-4-ol, 5-methyl-1-hexyn-3-ol, 2-methyl-1-butyn-2-ol, 1-trimethylsilylpropyne-3-ol, 2-butyn-1-ol, 2,4,7,9-tetramethyl-5-decyn-4,7-diol, 3,7,11-trimethyldodecyn-3-ol, 3-methyl-1-pentyn-3-ol, 3-methyl-1-dodecyn-3-ol, 3-pentyl-1-octyn-3-ol, 3-propyl-1-hexyn-3-ol, 3-methyl-1-tetradecyn-3-ol, 4-methyl-1-heptyn-3-ol, 4-ethyl-1-hexyn-3-ol, 1-heptyn-3-ol, 1-octyn-3-ol, 3-ethyl-1-hexyn-3-ol, etc.

[0021] Specifically, the alkynol compounds include but are not limited to at least one of the following formulas (21) to (41):

[0022]

[0023] The present invention also provides a preparation method of a platinum complex, which is obtained by successively carrying out coordination reactions with connected ligands using chloroplatinic acid as a raw material; furthermore, using chloroplatinic acid as a raw material, successively carrying out coordination reactions with tetramethyldivinyldisiloxane, organophosphorus compounds or alkynol compounds to obtain.

[0024] Specifically, first reduce chloroplatinic acid to generate a platinum intermediate, and then carry out coordination with organophosphorus compounds to obtain a platinum complex having the structure shown in formula (I); furthermore, the complex having the structure shown in formula (I) is coordinated with alkynol compounds to form a new platinum complex having the structure shown in formula (II) with multi-ligand synergistic coordination.

[0025] Specifically, it includes the following steps:

[0026] (1) Using chloroplatinic acid and tetramethyldivinyldisiloxane as raw materials, heating and reacting A under the catalysis of a basic substance to obtain a platinum complex connected with L 1 ligand;

[0027] (2) Mixing and heating the platinum complex connected with L 1 ligand with organophosphorus to carry out reaction B to obtain a platinum complex having the structure shown in formula (I).

[0028] In step (1), the mass ratio of chloroplatinic acid and tetramethyldivinyldisiloxane used can be 1:1 - 1:50.

[0029] In step (1), the mass of the basic substance used can be 0.5 - 10 times the mass of chloroplatinic acid.

[0030] In step (1), the conditions for the heating reaction can be stirring reaction at 40 - 90 °C for 0.5 - 24 h.

[0031] In step (1), the basic substance can include but is not limited to at least one of sodium carbonate, sodium bicarbonate, potassium bicarbonate, ammonium bicarbonate, etc.

[0032] In step (1), the reaction is preferably carried out in an alcohol solvent, such as including but not limited to at least one of methanol, ethanol, isopropanol, 1 - butanol, tert - butanol, 2 - butanol, isobutanol, and ethylene glycol. The reaction is preferably carried out under the protection of an inert gas. After the reaction, it can be filtered to remove the filter residue, and then the solvent is removed by rotary evaporation to obtain the product.

[0033] In step (2), the amount of the organic phosphorus used is 0.1 - 10 times the mass of chloroplatinic acid.

[0034] In step (2), the conditions for the heating reaction can be stirring reaction at 20 - 60 °C for 0.5 - 24 h.

[0035] In step (2), the reaction is preferably carried out in a benzene solvent, such as including but not limited to at least one of benzene, toluene, xylene, etc. After the reaction, the solvent is removed by rotary evaporation to obtain the product. The reaction is preferably carried out under the protection of an inert gas, such as argon.

[0036] Furthermore, when preparing the platinum complex shown in formula (Ⅱ), it is obtained by mixing and heating the platinum complex shown in formula (Ⅰ) with an alkynol compound for reaction C.

[0037] The amount of the alkynol compound used is 0.1 - 20 times the mass of chloroplatinic acid.

[0038] The conditions for the heating reaction C can be stirring reaction at 20 - 60 °C for 0.5 - 24 h.

[0039] The reaction is preferably carried out in a benzene solvent, such as including but not limited to at least one of benzene, toluene, xylene, etc. After the reaction, the solvent is removed by rotary evaporation to obtain the product. The reaction is preferably carried out under the protection of an inert gas, such as argon.

[0040] The platinum complex prepared by the method of the present invention can be directly stored or used, or it can be diluted with silicone oil and then stored or used. It can also be stored after dilution with saturated alkane solvents, and the saturated alkane solvents can include but are not limited to petroleum ether, solvent oil No. 120, D40 solvent oil, D60 solvent oil, D80 solvent oil, etc.

[0041] The platinum complex of the present invention has the characteristics of low activity at room temperature and can quickly recover its activity at high temperature. As a catalyst applied to addition-curable liquid silicone rubber, its characteristic of being able to be stably stored at room temperature for a long time greatly extends the stability and room temperature storage time of addition-curable liquid silicone rubber; at the same time, it can quickly recover its catalytic activity above 100 °C, enabling the addition-curable liquid silicone rubber to quickly complete vulcanization.

[0042] The present invention also provides the application of the above platinum complex in the field of addition-curable liquid silicone rubber.

[0043] The present invention also provides an addition-curable liquid silicone rubber, the components of which contain the above platinum complex. The addition-curable liquid silicone rubber containing the platinum complex provided by the present invention can be stably stored at room temperature for a long time and can be quickly vulcanized after being above 100 °C to obtain an addition-curable liquid silicone rubber.

[0044] The present invention also provides an addition-curable liquid silicone rubber, the components of which contain the above platinum complex, and the concentration of platinum is 1 to 20 ppm. The combination also contains conventional components, such as 100 parts of vinyl silicone oil, 0.5 to 5 parts of hydrogen-containing silicone oil, and may also contain other additives such as 0 to 30 parts of silica.

[0045] The present invention also provides a preparation method of the above addition-curable liquid silicone rubber, which can be obtained by adding the above platinum complex or the above platinum complex solution to vinyl silicone oil and stirring evenly, and then adding hydrogen-containing silicone oil, or other additives such as silica and mixing evenly; or by mixing vinyl silicone oil, hydrogen-containing silicone oil, or other additives such as silica evenly, and then adding the above platinum complex or the above platinum complex solution and stirring evenly.

[0046] The platinum complex solution refers to the platinum complex solution diluted with solvents such as silicone oil.

[0047] The addition-curable liquid silicone rubber provided by the present invention is preferably stored sealed and away from light at room temperature. During use, it is first constructed and then heated at 100 °C to 160 °C for vulcanization to obtain a cured product.

[0048] The platinum complex with multi-ligand cooperative coordination of the present invention has low activity at room temperature, which can greatly extend the stability and room-temperature storage time of addition-curing liquid silicone rubber. It can be stably stored at room temperature for more than 3 months. At the same time, when the temperature is higher than 100 °C, its catalytic activity can be quickly restored, enabling the addition-curing liquid silicone rubber to complete vulcanization rapidly, and the vulcanization can be completed within 10 minutes. The platinum complex of the present invention has the characteristics of simple preparation process, good catalytic performance, high stability, etc. It is a high-performance platinum catalyst that can greatly extend the stability and room-temperature storage time of addition-curing liquid silicone rubber and can catalyze the rapid vulcanization of addition-curing liquid silicone rubber at high temperature.

[0049] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0050] (1) The platinum complex of the present invention can be used as an effective catalyst for addition-curing liquid silicone rubber. The addition-curing liquid silicone rubber based on this catalyst can be stored for a long time at room temperature and can be rapidly vulcanized at a temperature higher than 100 °C.

[0051] (2) The addition-curing liquid silicone rubber based on the platinum complex of the present invention (platinum concentration 5 ppm) can be stably stored at room temperature for more than 3 months.

[0052] (3) The vulcanization time of the addition-curing liquid silicone rubber based on the platinum complex of the present invention (platinum concentration 5 ppm) at 120 °C is less than 10 minutes. Detailed implementation manners

[0053] The present invention will be further described in detail below in conjunction with embodiments, but the implementation manners of the present invention are not limited thereto. The materials involved in the following embodiments can be obtained from commercial channels without special instructions. The methods are conventional methods without special instructions. The dosages of each component are in parts by mass, parts by volume, g, mL.

[0054] Example 1:

[0055] A platinum complex PtP-1 is obtained by reacting chloroplatinic acid with tetramethyldivinyldisiloxane and tris(4-methoxyphenyl)phosphine. The reaction equation is as follows:

[0056]

[0057] In this example, the preparation method of the platinum complex PtP-1 includes the following steps:

[0058] (1) Add 1 part by mass of chloroplatinic acid, 5 parts by mass of potassium bicarbonate, 20 parts by mass of tetramethyldivinyldisiloxane, and 50 parts by volume of isopropanol as a solvent to the reaction flask in sequence. Under the protection of argon, heat up to 70 °C and react for 2 h.

[0059] (2) After the reaction is completed, a turbid intermediate solution is obtained. Filter it, add 50 parts by volume of xylene to the filtrate, remove isopropanol by rotary evaporation to displace the solvent, then add 1.36 parts by mass of tris(4-methoxyphenyl)phosphine, and react at 50 °C for 24 h under argon protection. Remove the solvent in the reaction solution by rotary evaporation to obtain the platinum complex PtP-1. The platinum complex PtP-1 can be directly used without further purification, or it can be dispersed in vinyl silicone oil or alkane solvents to prepare a dilute solution for use.

[0060] Example 2:

[0061] A platinum complex PtP-2 is obtained by reacting chloroplatinic acid with tetramethyldivinyldisiloxane and tris(4-butoxyphenyl) phosphite. The reaction equation is:

[0062]

[0063] In this example, the preparation method of the platinum complex PtP-2 includes the following steps:

[0064] (1) Add 1 part by mass of chloroplatinic acid, 4 parts by mass of sodium bicarbonate, 20 parts by mass of tetramethyldivinyldisiloxane, and 50 volumes of isopropanol as a solvent to the reaction flask in sequence. Heat to 70 °C and react for 2 h under argon protection.

[0065] (2) After the reaction is completed, a turbid intermediate solution is obtained. Filter it, add 50 parts by volume of xylene to the filtrate, remove isopropanol by rotary evaporation to displace the solvent, then add 2.03 parts by mass of tris(4-butoxyphenyl) phosphite, and react at 50 °C for 24 h under argon protection. Remove the solvent in the reaction solution by rotary evaporation to obtain the platinum complex PtP-2. The platinum complex PtP-2 can be directly used without further purification, or it can be dispersed in vinyl silicone oil or alkane solvents to prepare a dilute solution for use.

[0066] Example 3:

[0067] A platinum complex PtP-3 is obtained by reacting chloroplatinic acid with tetramethyldivinyldisiloxane and tris(4-butoxyphenyl) phosphite. The reaction equation is:

[0068]

[0069] In this example, the preparation method of the platinum complex PtP-3 includes the following steps:

[0070] (1) Add 1 part by mass of chloroplatinic acid, 2 parts by mass of sodium carbonate, 20 parts by mass of tetramethyldivinyldisiloxane, and 50 parts by volume of isopropanol as a solvent to the reaction flask in sequence. Heat to 70 °C and react for 2 h under argon protection.

[0071] (2) After the reaction is completed, a turbid intermediate solution is obtained, which is filtered. 50 volume parts of toluene are added to the filtrate, and isopropanol is removed by rotary evaporation to displace the solvent. Subsequently, 4.04 parts by mass of tris(4-butoxyphenyl) phosphite are added, and the reaction is carried out at 50 °C for 24 h under argon protection. The solvent in the reaction solution is removed by rotary evaporation to obtain the platinum complex PtP-3. The platinum complex PtP-3 can be used directly without further purification, or it can be dispersed in vinyl silicone oil or alkane solvents to prepare a dilute solution for use.

[0072] Example 4:

[0073] A platinum complex PtP-4 is obtained by reacting chloroplatinic acid with tetramethyldivinyldisiloxane and tris(4-tert-butylphenyl) phosphite. The reaction equation is as follows:

[0074]

[0075] In this example, the preparation method of the platinum complex PtP-4 includes the following steps:

[0076] (1) 1 part by mass of chloroplatinic acid, 4 parts by mass of sodium bicarbonate, 20 parts by mass of tetramethyldivinyldisiloxane are successively added to a reaction flask, and 50 volumes of isopropanol are used as a solvent. The temperature is raised to 70 °C and the reaction is carried out for 2 h under argon protection.

[0077] (2) After the reaction is completed, a turbid intermediate solution is obtained, which is filtered. 50 volumes of toluene are added to the filtrate, and isopropanol is removed by rotary evaporation to displace the solvent. Subsequently, 1.85 parts by mass of tris(4-tert-butylphenyl) phosphite are added, and the reaction is carried out at 50 °C for 24 h under argon protection. The solvent in the reaction solution is removed by rotary evaporation to obtain the platinum complex PtP-4. The platinum complex PtP-4 can be used directly without further purification, or it can be dispersed in vinyl silicone oil or alkane solvents to prepare a dilute solution for use.

[0078] Example 5:

[0079] A platinum complex PtP-5 is obtained by reacting chloroplatinic acid with tetramethyldivinyldisiloxane and tris(2-tert-butylphenyl) phosphite. The reaction equation is as follows:

[0080]

[0081] In this example, the preparation method of the platinum complex PtP-5 includes the following steps:

[0082] (1) Add 1 part by mass of chloroplatinic acid, 4 parts by mass of sodium bicarbonate, 10 parts by mass of tetramethyldivinyldisiloxane, and 50 volumes of isopropanol as a solvent to the reaction flask. Heat the mixture to 70 °C under argon protection and react for 5 h.

[0083] (2) After the reaction is completed, a turbid intermediate solution is obtained. Filter it, add 50 volumes of toluene to the filtrate, remove isopropanol by rotary evaporation to displace the solvent, then add 0.94 part by mass of tris(2-tert-butylphenyl) phosphite, and react at 50 °C for 24 h under argon protection. Remove the solvent of the reaction solution by rotary evaporation to obtain the platinum complex PtP-5. The platinum complex PtP-5 can be used directly without further purification, or it can be dispersed in vinyl silicone oil or alkane solvents to prepare a dilute solution for use.

[0084] Example 6:

[0085] A platinum complex PtP-6 is obtained by reacting chloroplatinic acid with tetramethyldivinyldisiloxane and tris(2-tert-butylphenyl) phosphite. The reaction equation is as follows:

[0086]

[0087] In this example, the preparation method of the platinum complex PtP-6 includes the following steps:

[0088] (1) Add 1 part by mass of chloroplatinic acid, 4 parts by mass of sodium bicarbonate, 10 parts by mass of tetramethyldivinyldisiloxane, and 50 volumes of isopropanol as a solvent to the reaction flask. Heat the mixture to 70 °C under argon protection and react for 1 h.

[0089] (2) After the reaction is completed, a turbid intermediate solution is obtained. Filter it, add 50 volumes of toluene to the filtrate, remove isopropanol by rotary evaporation to displace the solvent, then add 1.85 parts by mass of tris(2-tert-butylphenyl) phosphite, and react at 50 °C for 24 h under argon protection. Remove the solvent in the reaction solution by rotary evaporation to obtain the platinum complex PtP-6. The platinum complex PtP-6 can be used directly without further purification, or it can be dispersed in vinyl silicone oil or alkane solvents to prepare a dilute solution for use.

[0090] Example 7:

[0091] A platinum complex PtP-7 is obtained by reacting chloroplatinic acid with tetramethyldivinyldisiloxane and monophenylbis(2-ethylhexyl) phosphite. The reaction equation is as follows:

[0092]

[0093] In this example, the preparation method of the platinum complex PtP-7 includes the following steps:

[0094] (1) Add 1 part by mass of chloroplatinic acid, 4 parts by mass of potassium bicarbonate, 10 parts by mass of tetramethyldivinyldisiloxane, and 50 volumes of isopropanol as a solvent to the reaction flask in sequence. Heat to 70 °C under argon protection and react for 3 h.

[0095] (2) After the reaction, a turbid intermediate solution is obtained. Filter it, add 50 volumes of xylene to the filtrate, remove isopropanol by rotary evaporation to replace the solvent, then add 1.48 parts by mass of bis(2-ethylhexyl)phenyl phosphite, and react at 50 °C for 24 h under argon protection. Remove the solvent in the reaction solution by rotary evaporation to obtain the platinum complex PtP-7. The platinum complex PtP-7 can be used directly without further purification, or it can be dispersed in vinyl silicone oil or alkane solvents to prepare a dilute solution for use.

[0096] Example 8:

[0097] A platinum complex PtP-8 is obtained by reacting chloroplatinic acid with tetramethyldivinyldisiloxane and tris(2,4-di-tert-butylphenyl) phosphite. The reaction equation is:

[0098]

[0099] In this example, the preparation method of the platinum complex PtP-8 includes the following steps:

[0100] (1) Add 1 part by mass of chloroplatinic acid, 4 parts by mass of sodium bicarbonate, 15 parts by mass of tetramethyldivinyldisiloxane, and 50 volumes of isopropanol as a solvent to the reaction flask in sequence. Heat to 70 °C under argon protection and react for 5 h.

[0101] (2) After the reaction, a turbid intermediate solution is obtained. Filter it, add 50 volumes of toluene to the filtrate, remove isopropanol by rotary evaporation to replace the solvent, then add 1.25 parts by mass of tris(2,4-di-tert-butylphenyl) phosphite, and react at 50 °C for 24 h under argon protection. Remove the solvent in the reaction solution by rotary evaporation to obtain the platinum complex PtP-8. The platinum complex PtP-8 can be used directly without further purification, or it can be dispersed in vinyl silicone oil or alkane solvents to prepare a dilute solution for use.

[0102] Example 9:

[0103] A platinum complex PtP-9 is obtained by reacting chloroplatinic acid with tetramethyldivinyldisiloxane and tris(2,4-di-tert-butylphenyl) phosphite. The reaction equation is:

[0104]

[0105] In this embodiment, the preparation method of the platinum complex PtP-9 includes the following steps:

[0106] (1) Add 1 part by mass of chloroplatinic acid, 5 parts by mass of sodium bicarbonate, 20 parts by mass of tetramethyldivinyldisiloxane, and 50 volumes of isopropanol as a solvent to the reaction flask in sequence. Under the protection of argon, heat to 70 °C and react for 2 h.

[0107] (2) After the reaction is completed, a turbid intermediate solution is obtained. Filter it, add 50 volumes of toluene to the filtrate, remove isopropanol by rotary evaporation to replace the solvent, then add 2.45 parts by mass of tris(2,4-di-tert-butylphenyl) phosphite, and react at 50 °C for 24 h under the protection of argon. Remove the solvent in the reaction solution by rotary evaporation to obtain the platinum complex PtP-9. The platinum complex PtP-9 can be used directly without further purification, or it can be dispersed in vinyl silicone oil or alkane solvents to prepare a dilute solution for use.

[0108] Example 10:

[0109] A platinum complex PtP-10 is obtained by reacting chloroplatinic acid with tetramethyldivinyldisiloxane and tris(2-nonylphenyl) phosphite. The reaction equation is:

[0110]

[0111] In this embodiment, the preparation method of the platinum complex PtP-10 includes the following steps:

[0112] (1) Add 1 part by mass of chloroplatinic acid, 4 parts by mass of sodium bicarbonate, 20 parts by mass of tetramethyldivinyldisiloxane, and 50 volumes of isopropanol as a solvent to the reaction flask in sequence. Under the protection of argon, heat to 70 °C and react for 2 h.

[0113] (2) After the reaction is completed, a turbid intermediate solution is obtained. Filter it, add 50 volumes of toluene to the filtrate, remove isopropanol by rotary evaporation to replace the solvent, then add 2.66 parts by mass of tris(2-nonylphenyl) phosphite, and react at 50 °C for 24 h under the protection of argon. Remove the solvent in the reaction solution by rotary evaporation to obtain the platinum complex PtP-10. The platinum complex PtP-10 can be used directly without further purification, or it can be dispersed in vinyl silicone oil or alkane solvents to prepare a dilute solution for use.

[0114] Example 11:

[0115] A platinum complex PtP-11 is obtained by reacting chloroplatinic acid with tetramethyldivinyldisiloxane and tris(2-isooctyloxyphenyl) phosphite. The reaction equation is:

[0116]

[0117] In this embodiment, the preparation method of the platinum complex PtP-11 includes the following steps:

[0118] (1) Add 1 part by mass of chloroplatinic acid, 5 parts by mass of sodium bicarbonate, 20 parts by mass of tetramethyldivinyldisiloxane, and 50 volumes of isopropanol as a solvent to the reaction flask in sequence. Under argon protection, heat to 70 °C and react for 2 h.

[0119] (2) After the reaction is completed, obtain a turbid intermediate solution, filter it, add 50 volumes of toluene to the filtrate, remove isopropanol by rotary evaporation to displace the solvent, then add 2.68 parts by mass of tris(2-isooctyloxyphenyl) phosphite, and react at 50 °C for 24 h under argon protection. Remove the solvent in the reaction solution by rotary evaporation to obtain the platinum complex PtP-11. The platinum complex PtP-11 can be directly used without further purification, or the platinum complex PtP-11 can be dispersed in vinyl silicone oil or alkane solvents to prepare a dilute solution for use.

[0120] Example 12:

[0121] A platinum complex PtP-12 is obtained by reacting chloroplatinic acid with tetramethyldivinyldisiloxane, tris(2,4-di-tert-butylphenyl) phosphite, and ethynylcyclohexanol. The reaction equation is as follows:

[0122]

[0123] In this embodiment, the preparation method of the platinum complex PtP-12 includes the following steps:

[0124] (1) Add 1 part by mass of chloroplatinic acid, 4 parts by mass of sodium bicarbonate, 20 parts by mass of tetramethyldivinyldisiloxane, and 50 volumes of isopropanol as a solvent to the reaction flask in sequence. Under argon protection, heat to 70 °C and react for 2 h.

[0125] (2) After the reaction is completed, obtain a turbid intermediate solution, filter it, add 50 volumes of toluene to the filtrate, remove isopropanol by rotary evaporation to displace the solvent, then add 2.45 parts by mass of tris(2,4-di-tert-butylphenyl) phosphite, and react at 50 °C for 24 h under argon protection. Then add 0.48 part by mass of ethynylcyclohexanol and continue to react at 50 °C for 24 h under argon protection. Remove the solvent in the reaction solution by rotary evaporation to obtain the platinum complex PtP-12. The platinum complex PtP-12 can be directly used without further purification, or the platinum complex PtP-12 can be dispersed in vinyl silicone oil or alkane solvents to prepare a dilute solution for use.

[0126] Example 13:

[0127] A platinum complex PtP-13 is obtained by reacting chloroplatinic acid with tetramethyldivinyldisiloxane, tris(2,4-di-tert-butylphenyl) phosphite, and ethynylcyclohexanol. The reaction equation is as follows:

[0128]

[0129] In this example, the preparation method of the platinum complex PtP-13 includes the following steps:

[0130] (1) Add 1 part by mass of chloroplatinic acid, 5 parts by mass of sodium bicarbonate, 20 parts by mass of tetramethyldivinyldisiloxane, and 50 volumes of isopropanol as a solvent to the reaction flask in sequence. Under argon protection, heat it to 70 °C and react for 2 h.

[0131] (2) After the reaction, a turbid intermediate solution is obtained. Filter it, add 50 volumes of toluene to the filtrate, remove isopropanol by rotary evaporation to replace the solvent, then add 2.45 parts by mass of tris(2,4-di-tert-butylphenyl) phosphite, react at 50 °C for 24 h under argon protection, and then add 1.14 parts by mass of 3-methyl-1-dodecyn-3-ol and continue to react at 50 °C for 24 h under argon protection. Remove the solvent in the reaction solution by rotary evaporation to obtain the platinum complex PtP-13. The platinum complex PtP-13 can be used directly without further purification, or it can be dispersed in vinyl silicone oil or alkane solvents to prepare a dilute solution for use.

[0132] Comparative Example 1:

[0133] Take 77 parts by mass of vinyl silicone oil with a content of 0.1%, add an inhibitor: ethynylcyclohexanol (the content of the inhibitor in the silicone oil is 200 ppm), stir and mix evenly, then add Karstedt catalyst (the content of platinum in the silicone oil is 5 ppm), stir and mix evenly, and finally add 1 part by mass of hydrogen-containing silicone oil with a content of 0.43%, and continue to stir and mix evenly to obtain an addition-type two-component liquid silicone rubber.

[0134] (1) Store this addition-type liquid silicone rubber in a dark place, keep the ambient temperature at 25 °C, continuously observe the rheological properties of the addition-type liquid silicone rubber. When the addition-type two-component liquid silicone rubber loses fluidity, it is the end point of room temperature storage. Judge the stability of the system based on the duration of this experiment. The test results are shown in Table 1.

[0135] (2) Refer to the national standard GB 4806.11-2016 to test the vulcanization performance of the addition-type liquid silicone rubber. Coat this addition-type liquid silicone rubber on a special test film for a rubber vulcanization instrument, and then use the vulcanization instrument to test its vulcanization curve at 120 °C. Judge the high-temperature catalytic activity of the platinum complex based on the T90 vulcanization time. The test results are shown in Table 1.

[0136] Performance Test:

[0137] (1) Room Temperature Storage Period Experiment:

[0138] Take 77 parts by mass of vinyl silicone oil with a content of 0.1%, add one or several of platinum complexes PtP-1 to PtP-13, so that the platinum content in the silicone oil is 5 ppm, stir and mix evenly, and then add 1 part by mass of 0.43% hydrogen-containing silicone oil. After continuing to stir and mix evenly, an addition-curable liquid silicone rubber is obtained.

[0139] Store this addition-curable liquid silicone rubber in a light-proof place, keep the ambient temperature at 25 °C, continuously observe the rheological properties of the addition-curable silicone oil. When the addition-curable one-component liquid silicone rubber loses fluidity, it is the end point of room temperature storage. Judge the stability of the system based on the duration of this experiment. The test results are shown in Table 1.

[0140] (2) High Temperature Vulcanization Experiment:

[0141] Take 77 parts by mass of vinyl silicone oil with a content of 0.1%, add one or several of platinum complexes PtP-1 to PtP-13, so that the platinum concentration in the silicone oil is 5 ppm, stir and mix evenly, and then add 1 part by mass of 0.43% hydrogen-containing silicone oil. After continuing to stir and mix evenly, an addition-curable liquid silicone rubber is obtained.

[0142] Refer to the national standard GB 4806.11-2016 to test the vulcanization performance of the addition-curable liquid silicone rubber. Coat this addition-curable liquid silicone rubber on a special test film for a rubber vulcanization instrument, and then use the vulcanization instrument to test its vulcanization curve at 120 °C. Judge the high temperature catalytic activity of the platinum complex based on the T90 vulcanization time. The test results are shown in Table 1.

[0143] Table 1 T90 Vulcanization Time (120 °C) and Room Temperature Storage Period Test Results of Addition-Curable Liquid Silicone Rubber

[0144]

[0145]

[0146] As can be seen from Table 1, compared with Comparative Example 1, the platinum complex of the present invention greatly extends the storage period of the addition-curable liquid silicone rubber, and at the same time has excellent high-temperature catalytic activity, and can rapidly cure the addition-curable liquid silicone rubber within a vulcanization time of less than 30 min. Among them, when the platinum complexes PtP-1, PtP-2, PtP-5, PtP-7, and PtP-8 of the present invention are used alone for catalysis, compared with Comparative Example 1, the storage period of the addition-curable liquid silicone rubber is greatly extended, indicating that these platinum complexes can be used as catalysts for liquid silicone rubber. In particular, the vulcanization speed of the addition-curable liquid silicone rubber based on PtP-5 and PtP-8 is faster than that of Comparative Example 1, and the room-temperature stability is better, meaning that PtP-5 and PtP-8 are high-performance catalysts for addition-curable liquid silicone rubber and can well replace the catalytic system (Karstedt catalyst plus ethynylcyclohexanol) in Comparative Example 1. Further, the platinum complexes PtP-4, PtP-6, PtP-9, PtP-10, PtP-11, PtP-12, and PtP-13 of the present invention greatly extend the storage period of the addition-curable liquid silicone rubber, and the storage period is greater than 60 days, which fully meets the storage requirements of the addition-curable one-component liquid silicone rubber and can be used as an effective catalyst for the addition-curable one-component liquid silicone rubber. In addition, the room-temperature storage periods of the addition-curable liquid silicone rubber based on the platinum complexes PtP-10, PtP-11, and PtP-13 are all greater than 90 days, and T 90 The vulcanization time is less than 12 min, indicating that the platinum complex of the present invention is a catalyst with excellent performance for addition-curable one-component liquid silicone rubber.

[0147] The platinum complex with multi-ligand synergistic coordination of the present invention has the characteristics of low activity at room temperature and rapid recovery of activity at high temperature. When used as a catalyst in addition-curable liquid silicone rubber, it can be stably stored at room temperature for a long time, greatly extending the stability and room-temperature storage time of addition-curable liquid silicone rubber. The room-temperature storage period can be greater than 90 days; at a temperature higher than 100 °C, the catalytic activity can be rapidly restored, and the vulcanization speed of addition-curable liquid silicone rubber can be significantly accelerated, and vulcanization can be completed within 10 min.

[0148] The above are only preferred and better embodiments of the present invention, and do not impose any form of limitation on the present invention. Any technical solutions falling within the idea of the present invention belong to the protection scope of the present invention. For those skilled in the art, without departing from the principle and technical solutions of the present invention, many possible improvements and modifications can be made to the technical solutions of the present invention, or modified into equivalent embodiments with equivalent changes. Therefore, any simple modifications, equivalent replacements, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the technical solutions of the present invention still fall within the protection scope of the technical solutions of the present invention.

Claims

1. A platinum complex, characterized in that The molecular structural formula includes at least one of the structural formulas shown in formula (I) and formula (II): Wherein, L1 is tetramethyldivinyldisiloxane, L2 are the same or different and are respectively organic phosphorus compounds, and L3 is an acetylenic alcohol compound; x, y, and z are coordination numbers, x is 0 or 1; y is a natural number of 1-4, and z is a natural number of 1-20.

2. The platinum complex according to claim 1, characterized in that: The organophosphorus compounds include, but are not limited to, tris(4-methoxyphenyl)phosphine, tris(4-tert-butylphenyl)phosphite, tris(4-butoxyphenyl)phosphite, bis(2,4-di-tert-butylphenol)pentaerythritol diphosphite, tris(2-tert-butylphenyl)phosphite, di(2-tert-butylphenyl)-mono(2-nonylphenyl)phosphite, mono(2-tert-butylphenyl)-di(2-nonylphenyl)phosphite, tris(2-nonylphenyl)phosphite At least one of tris(trifluoroethyl) phosphite, tris(hexafluoroisopropyl) phosphite, tris(trimethylsilyl) phosphite, tris(allyl) phosphite and tris(propynyl) phosphite.

3. The platinum complex according to claim 1, characterized in that: The organophosphorus compound includes but is not limited to at least one of the following formulas (1) to (20):

4. The platinum complex according to claim 1, characterized in that: The alkynol compounds include but are not limited to cyclohexyl alkynol, cyclopentyl alkynol, 1-cyclohexylprop-2-yn-1-ol, 3,5-dimethyl-1-hexyn-3-ol, 2-methyl-5-octyne-4-ol, 5-methyl-1-hexyn-3-ol, 2-methyl-1-butyne-2-ol, 1-trimethylsilylpropyne-3-ol, 2-butyne-1-ol, 2,4,7,9-tetramethyl-5-decyne-4,7-diol, 3,7,1 At least one of 1-trimethyldodecyne-3-ol, 3-methyl-1-pentyne-3-ol, 3-methyl-1-dodecyne-3-ol, 3-pentyl-1-octyne-3-ol, 3-propyl-1-hexyne-3-ol, 3-methyl-1-tetradecyne-3-ol, 4-methyl-1-heptyne-3-ol, 4-ethyl-1-hexyne-3-ol, 1-heptyne-3-ol, 1-octyne-3-ol and 3-ethyl-1-hexyne-3-ol.

5. The platinum complex according to claim 1, characterized in that: The alkynol compound includes but is not limited to at least one of the following formulas (21) to (41):

6. A method for preparing a platinum complex, characterized in that The method is prepared by using chloroplatinic acid as a raw material and sequentially reacting with tetramethyldivinyldisiloxane, an organic phosphorus compound or an acetylene alcohol compound to obtain the product.

7. A method for preparing a platinum complex, characterized in that The specific steps include: (1) using chloroplatinic acid and tetramethyldivinyldisiloxane as raw materials, heating reaction A under the catalysis of alkaline substances to obtain a platinum complex connected with L1 ligand; (2) mixing a platinum complex connected with an L1 ligand and an organic phosphorus and heating them to react B to obtain a platinum complex with a structure represented by formula (I); When preparing the platinum complex of the structure shown in formula (II), the platinum complex of the structure shown in formula (I) is mixed with an alkynol compound and heated to react C to obtain the product.

8. Use of the platinum complex according to any one of claims 1 to 5 in the field of addition-type liquid silicone rubber.

9. An addition type liquid silicone rubber, characterized in that Its components contain the platinum complex described in any one of claims 1 to 5.

10. An addition type liquid silicone rubber, characterized in that Its components contain the platinum complex described in any one of claims 1 to 5, and the concentration of platinum is 1 to 20 ppm.

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