Preparation method of phenyl raw rubber and preparation method of phenyl silicone raw rubber

Abstract

The invention discloses a preparation method of phenyl raw rubber and a preparation method of phenyl silicone raw rubber, and belongs to the technical field of silicone rubber, and the prepared phenyl silicone raw rubber has good high and low temperature resistance and high mechanical strength. The method for preparing the phenyl raw rubber comprises the following steps: adding D4, D4vi and a methyl phenyl siloxane mixed ring body into a stirrer for stirring and mixing, heating to 55-95 DEG C, and carrying out vacuum dehydration for set time; adding a catalyst and an end-capping reagent, raising the temperature to 110-160 DEG C, introducing N2, and stirring to carry out polymerization reaction; after the reaction is finished, cooling the stirrer to normal temperature, adding a neutralizer, and stirring and neutralizing for a set time; the temperature is raised to 140-190 DEG C, and the vacuum dehydration time is set. Adding the raw phenyl rubber prepared by the method and zinc stearate into a kneading machine; then sequentially adding hydroxyl silicone oil, diphenyldihydroxysilane and fumed silica; and after kneading is completed, standing for a set time, and then carrying out vacuum treatment on the rubber compound.

Description

Technical Field

[0001] This invention belongs to the field of silicone rubber technology, specifically relating to a method for preparing phenyl raw rubber. Background Technology

[0002] Phenyl silicone rubber, commonly known as phenylene silica gel or phenyl silicone, is a high-performance elastomer material. Due to its excellent cold resistance, heat resistance, oxidation resistance, radiation resistance, and good electrical and chemical stability, phenyl silicone rubber is widely used in aerospace and other fields. In addition, it is also used in radiation-resistant rollers in copiers, fax machines, and laser printers to improve ozone resistance, antistatic properties, print and copy quality, and protect toner. It also has wide applications in medical equipment, sealing materials, and electronic encapsulation materials.

[0003] To improve the temperature resistance of phenyl silicone rubber, existing silicone rubbers are made by adding temperature-resistant agents to improve temperature resistance or enhance the mechanical properties of the material. Although these additives provide certain temperature resistance or reinforcement effects to silicone rubber, they will affect the hardness, elasticity and other properties of the rubber compound. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a method for preparing phenyl raw rubber and a method for preparing phenyl silicone raw rubber, the prepared phenyl silicone raw rubber exhibiting good high and low temperature resistance and high mechanical strength.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] First, a method for preparing phenyl raw gum is provided.

[0007] The raw materials for preparing phenyl gum include:

[0008] D4 0.1-100 parts by weight

[0009] D4 vi 0.01-10 parts by weight

[0010] 2-100 parts by weight of methylphenylsiloxane mixed ring

[0011] End-capping agent 0.001-1 parts by weight

[0012] Catalyst 0.01-10 parts by weight

[0013] Neutralizing agent 0.01-10 parts by weight;

[0014] The method for preparing phenyl raw gum includes the following steps:

[0015] Change D4, D4 viAdd the methylphenylsiloxane mixed ring to a mixer and mix. Heat the mixture to 55-95℃ and vacuum dehydrate for a set time.

[0016] Add catalyst and end-capping agent, raise temperature to 110-160℃, introduce N2 and stir to carry out polymerization reaction;

[0017] After the reaction is complete, cool the mixer to room temperature, add the neutralizing agent, and stir for the set time.

[0018] Set the vacuum dehydration time to between 140-190℃.

[0019] Preferably, the catalyst is an alkali metal silanolate, the neutralizing agent is acetic acid, and the capping agent is tetramethyldivinyldisiloxane.

[0020] Preferably, the catalyst is prepared by adding D4 and KOH to a reaction vessel, stirring and mixing, heating, vacuum dehydration, and reacting to generate an alkali metal silanolate.

[0021] Preferably, in the preparation method of the catalyst, D4 and KOH are stirred and mixed, and then heated to 60°C for vacuum dehydration for 2 hours.

[0022] Preferably, in the preparation method of the catalyst, after vacuum dehydration, the temperature is raised to 80°C, and N2 is introduced to carry out a stirring reaction for 2 hours.

[0023] Preferably, in the preparation method of the catalyst, KOH∶D4 = (0.1-2)∶99 parts by weight.

[0024] Preferably, the raw materials for preparing phenyl raw rubber include

[0025] D4 70 parts by weight

[0026] D4 vi 0.5 parts by weight

[0027] 30 parts by weight of methylphenylsiloxane mixed ring

[0028] 0.1 parts by weight of capping agent

[0029] 5 parts by weight of catalyst

[0030] Neutralizing agent 4 parts by weight.

[0031] In addition, a method for preparing phenyl silicone raw rubber is provided, wherein the phenyl raw rubber prepared by the above method and zinc stearate are added to a kneader; then hydroxyl silicone oil, diphenyl dihydroxysilane and fumed silica are added in sequence; after kneading is completed, the mixture is allowed to stand for a set time, and then the compound is subjected to vacuum treatment.

[0032] Preferably, the raw materials for preparing the styrene-silicone raw rubber include:

[0033] 100 parts by weight of phenyl raw rubber

[0034] 10-50 parts by weight of fumed silica

[0035] Hydroxy silicone oil 1-20 parts by weight

[0036] 1-10 parts by weight of diphenyl dihydroxysilane

[0037] 0-1 parts by weight of zinc stearate.

[0038] Preferably, the raw materials for preparing the styrene-silicone raw rubber include:

[0039] 100 parts by weight of phenyl raw rubber

[0040] 30 parts by weight of fumed silica

[0041] 8 parts by weight of hydroxy silicone oil

[0042] 6 parts by weight of diphenyldihydroxysilane

[0043] 0.15 parts by weight of zinc stearate.

[0044] According to the above technical solution, the present invention has the following beneficial effects:

[0045] Through D4 and D4 vi The precise control of the mixing ratio allows for direct control of the vinyl content in the rubber compound, resulting in higher mechanical strength and good elasticity in the finished product. Furthermore, D4 ​​is cheaper than D44. vi While meeting basic crosslinking requirements, using a higher D4 content can reduce raw material costs without significantly sacrificing performance. The siloxane backbone itself possesses excellent resistance to high and low temperatures, ozone, and ultraviolet radiation; the addition of D4 further enhances these properties, enabling the finished product to be used long-term within a temperature range of -60℃ to 200℃. vi The provided cross-linked structure is uniform, and combined with the flexible backbone of D4, it can reduce permanent deformation of the finished product after repeated stretching or compression, thus improving its service life. Methylphenylsiloxane mixed rings can introduce phenyl structures into siloxane materials, thereby simultaneously taking into account the weather resistance of siloxanes and the high-temperature resistance, radiation resistance, and optical properties brought by phenyl. In particular, the cyclic conjugated structure of phenyl enhances the thermal stability of the molecular chain, allowing the long-term service temperature of the resulting silicon material to be increased to 250℃~300℃, far exceeding the 200℃ upper limit of ordinary methylsiloxanes.

[0046] The specific technical solution of the present invention and its beneficial effects will be described in detail in the following specific embodiments. Detailed Implementation

[0047] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. 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.

[0048] Example 1

[0049] A method for preparing phenyl raw gum, wherein the raw materials for preparing phenyl raw gum include:

[0050] D4 (octamethylcyclotetrasiloxane) 0.1-100 parts by weight

[0051] D4 vi (Tetramethyltetravinylcyclotetrasiloxane) 0.01-10 parts by weight

[0052] 2-100 parts by weight of methylphenylsiloxane mixed ring

[0053] End-capping agent 0.001-1 parts by weight

[0054] Catalyst 0.01-10 parts by weight

[0055] Neutralizing agent: 0.01-10 parts by weight.

[0056] It is understandable that the weight proportions of the above raw material components can be varied according to requirements to obtain different hardness, tear strength, low temperature resistance, mechanical strength, etc.

[0057] For example, in some embodiments, the raw materials for preparing phenyl raw gum include

[0058] D4 70 parts by weight

[0059] D4 vi 0.5 parts by weight

[0060] 30 parts by weight of methylphenylsiloxane mixed ring

[0061] 0.1 parts by weight of capping agent

[0062] 5 parts by weight of catalyst

[0063] Neutralizing agent 4 parts by weight.

[0064] For example, in some embodiments, the raw materials for preparing phenyl raw gum include

[0065] D4 90 parts by weight

[0066] D4 vi 0.8 parts by weight

[0067] 40 parts by weight of methylphenylsiloxane mixed ring

[0068] 0.15 parts by weight of end-capping agent

[0069] 7 parts by weight of catalyst

[0070] Neutralizing agent, 5 parts by weight.

[0071] The method for preparing phenyl raw gum includes the following steps:

[0072] Change D4, D4 vi Add the methylphenylsiloxane mixed ring to a mixer and mix. Heat the mixture to 55-95℃ and vacuum dehydrate for a set time.

[0073] Add catalyst and end-capping agent, raise temperature to 110-160℃, introduce N2 and stir to carry out polymerization reaction;

[0074] After the reaction is complete, cool the mixer to room temperature, add the neutralizing agent, and stir for the set time.

[0075] Set the vacuum dehydration time to between 140-190℃.

[0076] In some embodiments, after stirring and mixing, the mixture can be heated to 60°C and vacuum dehydrated for 4 hours. During dehydration, the pressure gauge should be checked to ensure there are no leaks in the machine; the pressure gauge should reach -0.1 MPa. After dehydration, a catalyst and a capping agent are added, and the temperature is raised to 120°C.

[0077] During the polymerization equilibrium reaction, the stirring speed should be high at the beginning. Then observe the viscosity of the material. When the viscosity becomes significantly thicker, reduce the stirring speed. The polymerization reaction should last for 6-7 hours. After the mixer cools to room temperature, add the neutralizing agent and stir for 2 hours to neutralize. Then raise the temperature to 150℃ and dehydrate under vacuum for 2 hours. During dehydration, check the pressure gauge to see if there are any leaks in the machine. The pressure gauge should reach -0.1 MPa.

[0078] The above technical solution, through D4 and D4 vi The precise control of the mixing ratio allows for direct control of the vinyl content in the rubber compound, resulting in higher mechanical strength and good elasticity in the finished product. Furthermore, D4 ​​is cheaper than D44. viWhile meeting basic crosslinking requirements, using a higher D4 content can reduce raw material costs without significantly sacrificing performance. The siloxane backbone itself possesses excellent resistance to high and low temperatures, ozone, and ultraviolet radiation; the addition of D4 further enhances these properties, enabling the finished product to be used long-term within a temperature range of -60℃ to 200℃. vi The provided cross-linked structure is uniform, and combined with the flexible backbone of D4, it can reduce permanent deformation of the finished product after repeated stretching or compression, thus improving its service life. Methylphenylsiloxane mixed rings can introduce phenyl structures into siloxane materials, thereby simultaneously taking into account the weather resistance of siloxanes and the high-temperature resistance, radiation resistance, and optical properties brought by phenyl. In particular, the cyclic conjugated structure of phenyl enhances the thermal stability of the molecular chain, allowing the long-term service temperature of the resulting silicon material to be increased to 250℃~300℃, far exceeding the 200℃ upper limit of ordinary methylsiloxanes.

[0079] Among them, the methylphenylsiloxane mixed ring is a dimethyldiphenyl mixed ring. The core advantage of methylphenyl silicone rubber synthesized using dimethyldiphenyl mixed ring (the core component is diphenyldimethylcyclosiloxane) is that it balances temperature resistance and mechanical properties. It can be used for a long time at temperatures ranging from -60℃ to 200℃ (some formulations can reach 250℃). It is not prone to aging at high temperatures and does not become brittle at low temperatures. It has good tensile strength, tear strength and elastic recovery, and combines softness and durability.

[0080] In addition, the use of tetramethyldivinyldisiloxane as the end-capping agent can improve the reaction rate, enhance the properties of raw rubber, improve material characteristics, and modify the surface.

[0081] High crosslinking density: Tetramethyldivinyldisiloxane contains two vinyl groups, which can significantly increase the crosslinking density of silicone rubber. High crosslinking density helps optimize vulcanization properties and enhances the flexibility and strength of the finished product.

[0082] Enhancing Material Properties: Silicone rubber end-capped with tetramethyldivinyldisiloxane can improve the material's mechanical properties, heat resistance, and chemical corrosion resistance. This is because the end-capping agent can react with the active groups in the polymer chain to form stable chemical bonds, thereby improving the overall performance of the material.

[0083] Improving processing technology: Tetramethyldivinyldisiloxane can be used as an additive to improve the flowability of materials, reduce viscosity, and increase processing efficiency. At the same time, it can also reduce energy consumption during processing and lower production costs.

[0084] Surface modification: Due to its low surface energy, tetramethyldivinyldisiloxane can be used for surface modification of materials, improving their hydrophobicity, abrasion resistance, and stain resistance. This is particularly important for materials that need to be exposed to harsh environments for extended periods.

[0085] Preferably, acetic acid is used as the neutralizing agent, which can adjust the pH value, promote the reaction, and act as a preservative and solvent.

[0086] pH adjustment: Acetic acid can adjust the pH value of styrene-silicone raw rubber to keep it within a suitable pH range, thereby ensuring the efficient conduct of the neutralization reaction.

[0087] Accelerating reactions: In some chemical reactions, acetic acid can act as a catalyst or accelerator, promoting the reaction process. Acetic acid may play a similar role in the neutralization process of styrene-silicone raw rubber.

[0088] Preservative effect: Acetic acid has antibacterial properties, which can prevent the product from deteriorating during storage and use.

[0089] Solvent role: Acetic acid, as a solvent, helps to uniformly mix and disperse the components in styrene-silicone raw rubber, thereby improving the stability and performance of the product.

[0090] The catalyst is an alkali metal silanolate, and the preparation method of the catalyst is as follows:

[0091] D4 and KOH were added to a reaction vessel, stirred and mixed, heated, and dehydrated under vacuum to produce alkali metal silanolates.

[0092] First, add D4 and KOH to the reactor, seal it tightly to prevent air leakage, heat to 60℃ and dehydrate under vacuum for 2 hours. During dehydration, small bubbles will appear in the solution. Check the pressure gauge; it should read -0.1 MPa. After dehydration, heat to 80℃ and stir the reaction with N2 for 2 hours. During the reaction, small water droplets will appear at the vent of the reactor, and there will be a slight escaping sound.

[0093] In the preparation of alkali metal silanolates, the ratio of KOH:D4 is (0.1-2):99 parts by weight, for example, KOH:D4 = 1:99 parts by weight. However, in the process of preparing phenyl raw gum, the ratio of D4 to D4 in the preparation of alkali metal silanolates is 5:1 parts by weight.

[0094] In the reaction of benzene-silicone raw rubber, using alkali metal silanolates as catalysts has advantages such as increasing crosslinking density, improving processing performance, enhancing chemical resistance, increasing transparency, and imparting functionality.

[0095] Increasing crosslinking density: Alkali metal silanodes can undergo crosslinking reactions with styrene-silicone raw rubber to form a three-dimensional network structure, thereby increasing the crosslinking density of the material. This helps to enhance the material's mechanical strength, elasticity, and heat resistance.

[0096] Improved processing performance: Alkali metal silanodes can be used as crosslinking agents for room temperature vulcanizing (RTV) silicone rubber, enabling the raw silicone rubber to complete the vulcanization process at room temperature, simplifying the processing steps and improving production efficiency.

[0097] Enhanced chemical resistance: Through cross-linking reaction with alkali metal silanodes, the chemical resistance of styrene silicone raw rubber is improved, especially in its resistance to acid, alkali and other chemical substances.

[0098] Improved transparency: For certain applications, such as optical materials, the combination of styrene-silicone raw material with alkali metal silanolates can improve the transparency of the material, making it more suitable for use in optical devices such as lenses and optical fibers.

[0099] Imparting functionality: Alkali metal silanodes can also introduce other functional groups, such as hydrophobic, hydrophilic or conductive, thereby giving styrene-silicone raw rubber more functional properties and broadening its application fields.

[0100] Example 2

[0101] A method for preparing phenyl silicone raw rubber involves adding the phenyl raw rubber obtained in Example 1 and zinc stearate into a kneader; then sequentially adding hydroxyl silicone oil, diphenyl dihydroxysilane, and fumed silica (the fumed silica is added in batches); after kneading is completed, the mixture is allowed to stand for a set time (usually 24 hours) and then vacuum-treated.

[0102] The raw materials for preparing the styrene-silicone raw rubber include:

[0103] 100 parts by weight of phenyl raw rubber

[0104] 10-50 parts by weight of fumed silica

[0105] 1-10 parts by weight of hydroxyl silicone oil

[0106] 1-10 parts by weight of diphenyl dihydroxysilane

[0107] 0-1 parts by weight of zinc stearate.

[0108] In one embodiment, the raw materials for preparing the styrene-silicone raw rubber include:

[0109] 100 parts by weight of phenyl raw rubber

[0110] 30 parts by weight of fumed silica

[0111] 8 parts by weight of hydroxy silicone oil

[0112] 6 parts by weight of diphenyldihydroxysilane

[0113] 0.15 parts by weight of zinc stearate.

[0114] In one embodiment, the raw materials for preparing the styrene-silicone raw rubber include:

[0115] 100 parts by weight of phenyl raw rubber

[0116] 25 parts by weight of fumed silica

[0117] 6 parts by weight of hydroxy silicone oil

[0118] 7 parts by weight of diphenyldihydroxysilane

[0119] 0.15 parts by weight of zinc stearate.

[0120] It is understandable that the weight proportions of the above components can be varied according to requirements to obtain different hardness, tear strength, low temperature resistance, mechanical strength, etc.

[0121] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Those skilled in the art should understand that the present invention includes, but is not limited to, the content described in the above specific embodiments. Any modifications that do not depart from the functional and structural principles of the present invention will be included within the scope of the claims.

Claims

1. A method for preparing a phenyl raw rubber, characterized in that, the raw materials for preparing the phenyl raw rubber comprise: D4 0.1-100 parts by weight D4 vi 0.01-10 parts by weight methylphenylsiloxane mixed ring body 2-100 parts by weight capping agent 0.001-1 part by weight catalyst 0.01-10 parts by weight neutralizing agent 0.01-10 parts by weight; the method for preparing the phenyl raw rubber comprises the following steps: D4, D4 vi and methylphenylsiloxane mixed ring body into the blender stirring mixed, warming to 55-95 ℃ between vacuum dehydration set time; adding the catalyst and the capping agent, increasing the temperature to 110-160℃, and performing a polymerization reaction by blowing N2 and stirring; after the reaction is completed, cooling the stirring machine to room temperature, adding the neutralizing agent, and stirring and neutralizing for a set time; increasing the temperature to 140-190℃, and vacuum dewatering for a set time.

2. A process for the preparation of a phenylated raw rubber according to claim 1, characterized in that, The catalyst is an alkali metal silanol salt, the neutralizing agent is acetic acid, and the capping agent is tetramethyldivinyl disiloxane.

3. A process for the preparation of a phenylated raw rubber according to claim 2, characterized in that, The catalyst is prepared by adding D4 and KOH into a reaction kettle, stirring and mixing, increasing the temperature, vacuum dewatering, and reacting to form an alkali metal silanol salt.

4. A process for the preparation of a phenylated raw rubber according to claim 3, characterized in that, In the preparation method of the catalyst, after the D4 and KOH are stirred and mixed, the temperature is increased to 60℃, and vacuum dewatering is performed for 2H.

5. A process for the preparation of a phenylated raw rubber according to claim 4, characterized in that, In the preparation method of the catalyst, after the vacuum dewatering is completed, the temperature is increased to 80℃, N2 is blown, and stirring reaction is performed for 2H.

6. The process for the preparation of phenylated raw rubber according to claim 3, characterized in that, In the preparation method of the catalyst, KOH:D4= (0.1-2) :99 parts by weight.

7. The process for the preparation of phenylated raw rubber according to claim 1, characterized in that, The raw materials for preparing the phenyl raw rubber comprise D4 70 parts by weight D4 vi 0.5 parts by weight methylphenylsiloxane mixed ring body 30 parts by weight capping agent 0.1 part by weight catalyst 5 parts by weight neutralizing agent 4 parts by weight.

8. A process for the preparation of phenyl silicone gum, characterized by, The phenyl raw rubber prepared by the method in any one of claims 1 to 7 and zinc stearate are added into a kneader; then hydroxyl silicone oil, diphenyldihydroxysilane, and fumed silica are sequentially added; after kneading is completed, the mixture is left to stand for a set time, and then the vacuum treatment is performed on the rubber compound.

9. The method for preparing a styrene-silicone raw rubber according to claim 8, characterized in that, The raw materials for preparing the phenyl raw rubber comprise: phenyl raw rubber 100 parts by weight fumed silica 10-50 parts by weight hydroxyl silicone oil 1-10 parts by weight diphenyldihydroxysilane 1-20 parts by weight zinc stearate 0-1 part by weight.

10. The method for preparing a phenyl raw rubber according to claim 9, characterized in that, The raw materials for preparing the phenyl raw rubber comprise: phenyl raw rubber 100 parts by weight fumed silica 30 parts by weight hydroxyl silicone oil 8 parts by weight diphenyldihydroxysilane 6 parts by weight zinc stearate 0.15 parts by weight.