Bicyclic functionalized cyclotetrasiloxane monocomponent platinum catalyst, method of preparation and use thereof in hydrosilylation
Patent Information
- Application Number
- CN202610994663.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-07-06
- Publication Date
- 2026-09-29
AI Technical Summary
[0006]针对现有技术的不足，本发明提供了一种双环官能团化环四硅氧烷单组份铂催化剂、制备方法及其在硅氢加成中的应用，解决了用于工业化生产的单组分硅橡胶用铂催化剂仍面临制备过程繁琐、生产成本高、与硅橡胶制品相容性欠佳、抗黄变性不足的问题
1、本发明，利用二烯组分与四甲基四乙烯基环四硅氧烷发生[4+2]环加成反应制备双环官能团化环四硅氧烷，然后与卡斯特催化剂进行配体交换制备双环官能团化环四硅氧烷单组份铂催化剂；该制备方法简单，两步反应收率高，易于实现工业化生产；应用于硅橡胶制品时，无需添加额外的抑制剂，可实现较长操作时间，制品储存稳定性优异。
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Abstract
Description
Technical Field
[0001] This invention relates to the field of silicone rubber platinum catalyst technology, specifically to a bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst, its preparation method, and its application in hydrosilylation. Background Technology
[0002] Silicone rubber, a high-performance synthetic elastomer with polysiloxane as its core component, is widely used in extreme environments, life sciences, high-tech industries, and everyday applications due to its ability to balance elasticity, stability, and safety. It has become a key component of modern engineering materials. The vulcanization process for silicone rubber products is mainly divided into peroxide vulcanization and platinum-catalyzed vulcanization. Platinum-catalyzed vulcanization, with its outstanding advantages of environmental friendliness, high reaction efficiency, and excellent product purity, is currently the mainstream vulcanization technology in industrial production.
[0003] In platinum-catalyzed sulfidation (addition sulfidation) systems, Castells catalysts are a crucial class of high-performance platinum catalysts, with core advantages including: 1) extremely high catalytic activity and selectivity; 2) excellent solubility and compatibility with matrix materials; and 3) good thermal and storage stability. However, these catalysts also have significant technical drawbacks: 1) they are prone to "poisoning" deactivation: their catalytic activity is easily poisoned by Lewis bases containing lone pairs of electrons, leading to permanent deactivation. Typical poisoning substances include compounds containing nitrogen, phosphorus, sulfur, tin, and heavy metal ions; 2) catalytic activity is difficult to effectively inhibit at room temperature, resulting in short operating times and poor storage stability in silicone rubber compositions.
[0004] To address these issues, the industry is committed to developing highly stable and highly active single-component platinum catalysts. For example, by regulating platinum catalysts with ligands, a controllable activity mechanism of "room temperature stability - high temperature decomposition" can be achieved, thereby realizing the synergistic optimization of catalytic activity and stability.
[0005] Despite significant advancements in ligand regulation technology, platinum catalysts for single-component silicone rubber used in industrial production still face challenges such as cumbersome preparation processes, high production costs, poor compatibility with silicone rubber products, and insufficient resistance to yellowing. Summary of the Invention
[0006] To address the shortcomings of existing technologies, this invention provides a bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst, its preparation method, and its application in hydrosilylation. This solves the problems faced by platinum catalysts for single-component silicone rubber used in industrial production, such as cumbersome preparation process, high production cost, poor compatibility with silicone rubber products, and insufficient resistance to yellowing.
[0007] To achieve the above objectives, the present invention provides the following technical solution: A bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst, comprising: tetramethyltetravinylcyclotetrasiloxane, diene component, organic solvent, and cassiterite catalyst.
[0008] Preferably, the raw material comprises, by weight: 4-5 parts tetramethyltetravinylcyclotetrasiloxane, 0.9-4 parts diene component, 2-50 parts organic solvent, and 9-39 parts caster catalyst.
[0009] Preferably, the diene component is one of cyclopentadiene and furan.
[0010] Preferably, the organic solvent is one or more of toluene, xylene, and tetrahydrofuran.
[0011] Application of a bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst in hydrosilylation.
[0012] A method for preparing a bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst includes the following steps: Step 1: Preparation of bicyclic functionalized cyclotetrasiloxanes: Tetramethyltetravinylcyclotetrasiloxane was added to a three-necked round-bottom flask, followed by the addition of an organic solvent and a diene component. The system was purged three times under nitrogen, and the temperature was raised to 60℃-160℃ for reaction. After the reaction was confirmed to be complete by TLC, the system was cooled to room temperature, and then extracted, concentrated, and purified by silica gel column chromatography to obtain bicyclic functionalized cyclotetrasiloxane. Step 2: Preparation of a bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst: Bicyclic functionalized cyclotetrasiloxane was added to a three-necked round-bottom flask, followed by the addition of an organic solvent and stirring until homogeneous. Then, a caster catalyst was added, and the system was purged three times under nitrogen atmosphere. The temperature was raised to 50℃-80℃ for reaction. The reaction was monitored by TLC until the reactants were fully reacted. The system was then cooled to room temperature, filtered, washed with an alcohol solvent, and dried to obtain a single-component platinum catalyst with bicyclic functionalized cyclotetrasiloxane.
[0013] Preferably, the alcohol solvent used for washing in step two is one or a mixture of methanol, ethanol, and isopropanol.
[0014] Preferably, the diene component is one of cyclopentadiene and furan.
[0015] Preferably, the organic solvent is one or more of toluene, xylene, and tetrahydrofuran.
[0016] Application of a bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst prepared by a method for hydrosilylation.
[0017] This invention provides a bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst, its preparation method, and its application in hydrosilylation. It possesses the following beneficial effects: 1. This invention utilizes a diene component to undergo a [4+2] cycloaddition reaction with tetramethyltetravinylcyclotetrasiloxane to prepare a bicyclic functionalized cyclotetrasiloxane, which is then exchanged with a Castiglione catalyst to prepare a single-component platinum catalyst for the bicyclic functionalized cyclotetrasiloxane. This preparation method is simple, has a high yield in two steps, and is easy to implement for industrial production. When applied to silicone rubber products, no additional inhibitors are required, allowing for longer operating times and excellent product storage stability. Attached Figure Description
[0018] Figure 1 This is a flowchart illustrating the preparation process of a bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst proposed in this invention.
[0019] Wherein, S-1 represents a bicyclic functionalized cyclotetrasiloxane; S-2 represents a bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst. Detailed Implementation
[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example
[0021] This invention provides a method for preparing a bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst, comprising the following specific steps: Step 1, Bicyclic functionalization of cyclotetrasiloxane S-1A: 4.47 g of tetramethyltetravinylcyclotetrasiloxane was added to a 100 mL three-necked round-bottom flask, followed by 50 mL of toluene, and then 0.95 g of cyclopentadiene. The system was purged three times under nitrogen atmosphere and reacted at 80 °C for 4 h. After confirming the complete reaction by TLC, the system was cooled to room temperature, extracted, concentrated, and purified by silica gel column chromatography to obtain 4.68 g of bicyclic functionalized cyclotetrasiloxane S-1A.
[0022] Step 2, Bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst S-2A: 4.24 mg of bicyclic functionalized cyclotetrasiloxane S-1A was added to a three-necked round-bottom flask, followed by 2 mL of toluene and stirring until homogeneous. Then, 9.75 g of caster catalyst was added. The system was purged three times under nitrogen atmosphere and reacted at 50 °C for 2 h. TLC monitoring showed that the reaction of the starting material was complete. The system was then cooled to room temperature, filtered, washed with alcohol solvent, and dried to obtain 8.05 mg of bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst S-2A.
[0023] Step 3: Add 8.05 mg S-2A to a round-bottom flask, add 200 mg toluene, then add 188 mg vinyl silicone oil (vinyl content 1.08%), stir well to obtain platinum catalyst C1 (platinum concentration 5000 ppm). Example
[0024] Step 1, Bicyclic functionalization of cyclotetrasiloxane S-1B: 4.47 g of tetramethyltetravinylcyclotetrasiloxane was added to a 100 mL three-necked round-bottom flask, followed by 50 mL of toluene, and then 3.63 g of cyclopentadiene. The system was purged three times under nitrogen atmosphere and reacted at 80 °C for 10 h. After confirming the complete reaction by TLC, the system was cooled to room temperature, extracted, concentrated, and purified by silica gel column chromatography to obtain 6.32 g of bicyclic functionalized cyclotetrasiloxane S-1B.
[0025] Step 2, Bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst S-2B: 6.08 mg of bicyclic functionalized cyclotetrasiloxane S-1B was added to a three-necked round-bottom flask, followed by 2 mL of toluene and stirring until homogeneous. Then, 39 g of caster catalyst was added. The system was purged three times under nitrogen atmosphere and reacted at 50 °C for 2 h. TLC monitoring showed that the reaction of the starting material was complete. The system was then cooled to room temperature, filtered, washed with alcohol solvent, and dried to obtain 9.89 mg of bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst S-2B.
[0026] Step 3: Add 9.89 mg S-2B to a round-bottom flask, add 200 mg toluene, and then add 1.35 g vinyl silicone oil (vinyl content 1.08%). Stir well to obtain platinum catalyst C2 (platinum concentration 5000 ppm). Example
[0027] Step 1, Bicyclic functionalization of cyclotetrasiloxane S-1C: 4.47 g of tetramethyltetravinylcyclotetrasiloxane was added to a 100 mL three-necked round-bottom flask, followed by 50 mL of xylene, and then 0.984 g of furan. The system was purged three times under nitrogen atmosphere and reacted at 120 °C for 2 h. After confirming the complete reaction by TLC, the system was cooled to room temperature, extracted, concentrated, and purified by silica gel column chromatography to obtain 4.59 g of bicyclic functionalized cyclotetrasiloxane S-1C.
[0028] Step 2, Bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst S-2C: 4.26 mg of bicyclic functionalized cyclotetrasiloxane S-1C was added to a three-necked round-bottom flask, 2 mL of toluene was added and stirred until homogeneous, followed by 9.75 g of caster catalyst. The system was purged three times under nitrogen atmosphere and reacted at 80 °C for 2 h. TLC monitoring showed that the reaction of the starting material was complete. The system was cooled to room temperature, filtered, washed with alcohol solvent, and dried to obtain 8.07 mg of bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst S-2B.
[0029] Step 3: Add 8.07 mg S-2C to a round-bottom flask, add 200 mg toluene, then add 188 mg vinyl silicone oil (vinyl content 1.08%), stir well to obtain platinum catalyst C3 (platinum concentration 5000 ppm). Example
[0030] Step 1, Bicyclic functionalization of cyclotetrasiloxane S-1D: 4.47 g of tetramethyltetravinylcyclotetrasiloxane was added to a 100 mL three-necked round-bottom flask, followed by 50 mL of xylene, and then 3.54 g of furan. The system was purged three times under nitrogen atmosphere and reacted at 120 °C for 8 h. After confirming the complete reaction by TLC, the system was cooled to room temperature, extracted, concentrated, and purified by silica gel column chromatography to obtain 6.97 g of bicyclic functionalized cyclotetrasiloxane S-1D.
[0031] Step 2, Bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst S-2D: 6.16 mg of bicyclic functionalized cyclotetrasiloxane S-1D was added to a three-necked round-bottom flask, 2 mL of toluene was added and stirred until homogeneous, followed by the addition of 39 g of caster catalyst. The system was purged three times under nitrogen atmosphere and reacted at 80 °C for 6 h. TLC monitoring showed that the reaction of the starting material was complete. The system was then cooled to room temperature, filtered, washed with alcohol solvent, and dried to obtain 9.97 mg of bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst S-2D.
[0032] Step 3: Add 9.97 mg S-2D to a round-bottom flask, add 200 mg toluene, then add 1.35 g vinyl silicone oil (vinyl content 1.08%), stir well to obtain platinum catalyst C4 (platinum concentration 5000 ppm).
[0033] Comparative Example 1: A complex system of cascade catalyst C5 (platinum concentration of 5000 ppm) and acetylenecyclohexanol.
[0034] a. Testing of high-temperature vulcanization performance Four 100g portions of liquid silicone rubber (Shenzhen Zhengan Organosilicon Technology Co., Ltd.) were taken, and 0.2g of C1-C4 (5000ppm) was added to each. The mixture was stirred for five minutes and then vulcanized at 160℃ for 5 minutes to obtain silicone rubber samples A, B, C, and D. Another 100g portion of the same liquid silicone rubber was taken, and 0.3% acetylenecyclohexanol was added. The mixture was stirred for 5 minutes, and then 0.2g of C5 (5000ppm) was added to obtain silicone rubber sample E. The vulcanization characteristics were tested using a vulcanization apparatus, and the results are shown in Table 1.
[0035] Table 1 below shows the vulcanization results of silicone rubber samples A, B, C, D, and E prepared in the examples and comparative examples.
[0036]
[0037] As shown in Table 1, the bicyclic functionalized single-component platinum catalysts C1-C4 prepared in this invention, when applied to silicone rubber systems, do not require the addition of additional inhibitors. Their high-temperature vulcanization characteristics are similar to those of the traditional caster catalyst-ethynylcyclohexanol inhibitor system (sample D). All samples can vulcanize normally under high-temperature conditions, demonstrating that the bicyclic functionalized cyclotetrasiloxane single-component platinum catalysts (S-2A, S-2B, S-2C, S-2D) possess excellent catalytic activity.
[0038] b. Room temperature stability test Four 100g portions of liquid silicone rubber (Shenzhen Zhengan Organosilicon Technology Co., Ltd.) were taken, and 0.2g of catalyst diluent C1-C4 were added to each to prepare samples A1, B1, C1, and D1, respectively. Another 100g of the same liquid silicone rubber was taken, and 0.3% acetylenecyclohexanol was added. After stirring for 5 minutes, 0.2g of C5 (5000ppm) was added to obtain silicone rubber sample E1. All samples were sealed and placed in a constant temperature environment of 25℃. The viscosity of the system was measured periodically using an NDJ-8S rotational viscometer (Shanghai Changji Geological Instrument Co., Ltd.) to investigate storage stability. The results are shown in Table 2.
[0039] Table 2 below shows the viscosity changes of silicone rubber samples A1, B1, C1, D1, and E1 prepared in the examples and comparative examples at 25°C.
[0040]
[0041] As shown in Table 2, when the catalysts (C1-C4) prepared in this invention are applied to silicone rubber, samples A1 and C1 show a sharp increase in viscosity to over 10,000 mPa·s after 30 days of storage at 25°C, making subsequent molding impossible. Sample E1 shows a viscosity increase to over 10,000 mPa·s after 10 days of storage, while samples B1 and D1 show a smaller viscosity change (≤10%) after 60 days of storage. This comparison shows that as the proportion of bicyclic functional groups increases, the catalyst's inhibition of platinum at room temperature is enhanced, thereby increasing the storage stability of silicone rubber products at room temperature.
[0042] As can be seen from Tables 1 and 2, the tetrasubstituted single-component platinum catalysts S-2B and S-2D with bicyclic functional groups prepared by the method of the present invention exhibit good stability at room temperature when applied to single-component silicone rubber. They can also achieve crosslinking and curing reactions normally under high temperature conditions. These single-component platinum catalysts are beneficial for the storage and transportation of silicone rubber and are suitable for single-component silicone rubber.
[0043] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst, characterized in that, Raw materials include: Tetramethyltetravinylcyclotetrasiloxane, diene component, organic solvent, caster catalyst.
2. The bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst according to claim 1 is characterized in that, The raw materials, by weight, include: 4-5 parts tetramethyltetravinylcyclotetrasiloxane, 0.9-4 parts diene component, 2-50 parts organic solvent, and 9-39 parts caster catalyst.
3. The bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst according to claim 2, characterized in that: The diene component is one of cyclopentadiene and furan.
4. The bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst according to claim 2, characterized in that: The organic solvent is one or more of toluene, xylene, and tetrahydrofuran.
5. A method for preparing a bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst, characterized in that, Includes the following steps: Step 1: Preparation of bicyclic functionalized cyclotetrasiloxanes: Tetramethyltetravinylcyclotetrasiloxane was added to a three-necked round-bottom flask, followed by the addition of an organic solvent and a diene component. The system was purged three times under nitrogen, and the temperature was raised to 60℃-160℃ for reaction. After the reaction was confirmed to be complete by TLC, the system was cooled to room temperature, and then extracted, concentrated, and purified by silica gel column chromatography to obtain bicyclic functionalized cyclotetrasiloxane. Step 2: Preparation of a bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst: Bicyclic functionalized cyclotetrasiloxane was added to a three-necked round-bottom flask, followed by the addition of an organic solvent and stirring until homogeneous. Then, a caster catalyst was added, and the system was purged three times under nitrogen atmosphere. The temperature was raised to 50℃-80℃ for reaction. The reaction was monitored by TLC until the reactants were fully reacted. The system was then cooled to room temperature, filtered, washed with an alcohol solvent, and dried to obtain a single-component platinum catalyst with bicyclic functionalized cyclotetrasiloxane.
6. The method for preparing a bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst according to claim 5, characterized in that: The alcohol solvent used for washing in step two is one or a mixture of methanol, ethanol, and isopropanol.
7. The method for preparing a bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst according to claim 5, characterized in that: The diene component is one of cyclopentadiene and furan.
8. The method for preparing a bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst according to claim 5, characterized in that: The organic solvent is one or more of toluene, xylene, and tetrahydrofuran.
9. The application of a bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst according to any one of claims 1-4 in hydrosilylation.
10. The application of the bicyclic functionalized cyclotetrasiloxane single-component platinum catalyst prepared by the method according to any one of claims 5-8 in hydrosilylation.