Low-temperature-resistant fluororubber compound and preparation method thereof

Abstract

The invention discloses a low-temperature-resistant fluororubber compound and a preparation method thereof. Comprising the following components in parts by weight: 100 to 105 parts of ternary polymerization fluororubber 2462, 5 to 10 parts of magnesium oxide 150, 6 to 10 parts of calcium hydroxide, 20 to 26 parts of wollastonite, 15 to 20 parts of diatomite 499, 3 to 5 parts of a coloring agent, 15 to 18 parts of viscose-based carbon fiber, 3 to 6 parts of RL-28, 0.6 to 1 part of an accelerant BPP, 2 to 5 parts of bisphenol AF, 2 to 5 parts of nano silicon dioxide, 3 to 5 parts of a low-temperature vulcanizing agent and 3 to 5 parts of a bio-based plasticizer. According to the present invention, the low-temperature curing agent and the bio-based plasticizer are used to further solve the problem of low-temperature embrittlement of the traditional material, and the production process is matched to use so as to achieve the good tensile strength, such that the low-temperature curing agent and the bio-based plasticizer are adopted to further solve the low-temperature embrittlement problem of the traditional material; the nano silicon dioxide can be fully dispersed in the use process, so that the use effect of the nano silicon dioxide is improved.

Description

Technical Field

[0001] The invention relates to the technical field of low-temperature resistant fluororubber production, in particular to a low-temperature resistant fluororubber compound and a preparation method thereof. Background Art

[0002] Compared with other synthetic rubbers, fluororubber has significant advantages in heat resistance, oil resistance and chemical resistance. It is widely used in automotive fuel pipes, hoses, gaskets and other purposes, and has excellent resistance to oil, ethanol mixed fuels, etc. It has low fuel permeability, so it also meets the more stringent automotive industry regulations on gas emissions, and provides good fluidity and outstanding compression set.

[0003] However, the existing technology still has major deficiencies, such as:

[0004] Fluororubber in the prior art often becomes brittle at low temperatures. As a result, fluororubber often gets damaged in low temperature environments. Although the prior art also uses additives to solve this technical problem to a certain extent, simply adding additives without corresponding processes often cannot solve this technical problem well. Summary of the invention

[0005] The object of the present invention is to provide a low temperature resistant fluororubber compound and a preparation method thereof, so as to solve the problems raised in the above background technology.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A low-temperature resistant fluororubber compound comprises 100-105 parts of ternary polymerized fluororubber 2462, 5-10 parts of magnesium oxide 150, 6-10 parts of calcium hydroxide, 20-26 parts of wollastonite, 15-20 parts of diatomaceous earth 499, 3-5 parts of colorant, 15-18 parts of viscous carbon fiber, 3-6 parts of RL-28, 0.6-1 parts of accelerator BPP, 2-5 parts of bisphenol AF, 2-5 parts of nano silicon dioxide, 3-5 parts of low-temperature vulcanizer and 3-5 parts of bio-based plasticizer.

[0008] Preferably, the colorant is aniline black, azo dye, etc.

[0009] Preferably, the low-temperature vulcanizer is ammonium phosphite, and the bio-based plasticizer is polylactic acid.

[0010] A method for preparing a low-temperature resistant fluororubber compound comprises the following steps:

[0011] S1: prepare raw materials;

[0012] S2: pre-treated nano-silica;

[0013] S3: Add plasticizer and vulcanizer;

[0014] S4: cooling and forming;

[0015] S5: Vulcanization treatment.

[0016] Preferably, the step S1: preparing raw materials comprises the following steps:

[0017] S11: Prepare all raw materials in a clean laboratory environment;

[0018] S12: Prepare the mixing equipment and ensure that it is cleaned and in good working condition before use.

[0019] S13: Weigh all raw materials according to the above proportions to ensure accuracy;

[0020] Preferably, S2: pre-treating nano-silicon dioxide comprises the following steps:

[0021] S21: Surface treatment: Before adding nano-silica, its surface is modified by chemical or physical methods to improve its compatibility in a specific matrix. It can be treated by coating with organic compounds or silane to make its surface have better affinity;

[0022] Alternatively, wet dispersion, i.e. premixing in the liquid phase, premixing the nanosilica with the solvent and then mixing with other ingredients, can help reduce aggregation between silica particles;

[0023] S22: Preliminary mixing: dry mixing of nano-silicon dioxide and other solid components. In this stage, high-speed stirring is used to preliminarily disperse the nano-silicon dioxide.

[0024] S23: Adding dispersing aid: Adding a proper amount of dispersing aid can effectively reduce the interaction force between nanoparticles and prevent them from aggregating.

[0025] S24: Wet mixing stage:

[0026] Add liquid ingredients gradually: During the dry mixing process, add liquid ingredients gradually and keep stirring to ensure that the nano-silica can be fully wetted.

[0027] S25: Increase the mixing temperature: Properly increasing the temperature during the wet mixing process can reduce the mixing viscosity, help the material flow, and promote uniform dispersion.

[0028] S26: Using ultrasonic treatment:

[0029] After the mixing is completed, the mixture can be subjected to ultrasonic treatment for 5-10 minutes to further improve the dispersion effect.

[0030] Preferably, S3: adding a plasticizer and a vulcanizing agent comprises the following steps:

[0031] After mixing well, add the bio-based plasticizer and low-temperature vulcanizer gradually. The operating temperature should be kept at 70°C and the mixing time should be 5 minutes to ensure full dispersion.

[0032] Preferably, S4: cooling and molding comprises the following steps:

[0033] The uniformly mixed rubber was taken out from the equipment and allowed to cool to 25°C at room temperature.

[0034] The cooled rubber mixture is molded into a mold and pressed into the desired product shape.

[0035] Preferably, S5: vulcanization treatment comprises the following steps:

[0036] The formed rubber compound is placed in a vulcanizing furnace, the temperature is set to 180°C, and the vulcanization time is 30 minutes to ensure full vulcanization and form ideal physical properties.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] 1. By adding nano-silicon dioxide, it is ensured to have better tensile strength, making it less likely to become brittle in a low-temperature environment. By using low-temperature vulcanizers and bio-based plasticizers, the problem of traditional materials becoming brittle at low temperatures is further solved;

[0039] 2. Through the combination of production processes, it is ensured that nano-silicon dioxide can be fully dispersed during use to improve its use effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 A process flow chart is produced for the present invention. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] See also Figure 1 , the present invention provides a technical solution:

[0043] A low-temperature resistant fluororubber compound comprises 100 parts of ternary polymer fluororubber 2462, 5 parts of magnesium oxide 150, 6 parts of calcium hydroxide, 20 parts of wollastonite, 15 parts of diatomaceous earth 499, 3 parts of colorant, 15 parts of viscous carbon fiber, 3 parts of RL-28, 0.6 parts of accelerator BPP, 2 parts of bisphenol AF, 2 parts of nano silicon dioxide, 3 parts of low-temperature vulcanizer and 3 parts of bio-based plasticizer.

[0044] Colorants include aniline black, azo dyes, etc.

[0045] The low-temperature vulcanizer is ammonium phosphite and the bio-based plasticizer is polylactic acid.

[0046] A method for preparing a low-temperature resistant fluororubber compound comprises the following steps:

[0047] S1: prepare raw materials;

[0048] S11: Prepare all raw materials in a clean laboratory environment;

[0049] S12: Prepare the mixing equipment and ensure that it is cleaned and in good working condition before use.

[0050] S13: Weigh all raw materials according to the above proportions to ensure accuracy;

[0051] The mixing equipment in this embodiment can use an open mixer or an internal mixer, both of which are well known to those skilled in the art and will not be described in detail herein. Preparing in a clean laboratory environment can avoid interference from impurities and ensure the purity and quality of the final product. Selecting the right mixing equipment is also the key to ensuring uniform mixing and temperature control.

[0052] S2: pre-treated nano-silica;

[0053] S21: Surface treatment: Before adding nano-silica, its surface is modified by chemical or physical methods to improve its compatibility in a specific matrix. It can be treated by coating with organic compounds or silane to make its surface have better affinity;

[0054] Alternatively, wet dispersion, i.e. premixing in the liquid phase, premixing the nanosilica with the solvent and then mixing with other ingredients, can help reduce aggregation between silica particles;

[0055] S22: Preliminary mixing: dry mixing of nano-silicon dioxide and other solid components. In this stage, high-speed stirring is used to preliminarily disperse the nano-silicon dioxide.

[0056] S23: Adding dispersing aid: Adding a proper amount of dispersing aid can effectively reduce the interaction force between nanoparticles and prevent them from aggregating.

[0057] S24: Wet mixing stage:

[0058] Gradually add liquid ingredients: During the dry mixing process, gradually add liquid ingredients (such as fluororubber matrix, accelerator, etc.) and keep stirring to ensure that the nano-silica can be fully infiltrated.

[0059] S25: Increase the mixing temperature: Properly increasing the temperature during the wet mixing process can reduce the mixing viscosity, help the material flow, and promote uniform dispersion.

[0060] S26: Using ultrasonic treatment:

[0061] After the mixing is completed, the mixture can be subjected to ultrasonic treatment for 5-10 minutes to further improve the dispersion effect.

[0062] The S2 step in this embodiment is to ensure that the nano-silicon dioxide is distributed more evenly during use and to ensure its effect. This step provides two methods that help to make the nano-silicon dioxide more evenly distributed, namely surface treatment and wet dispersion. The solvent in the wet dispersion can be water, and the added dispersing aid mentioned in S23 can be a surfactant. The temperature in S25 is generally around 60 degrees Celsius. Through surface modification, the hydrophilicity or hydrophobicity of the nano-silicon dioxide can be changed to make it more compatible with the matrix material, reduce the interaction force, and thus improve the dispersion uniformity. Through wet dispersion, premixing in the liquid phase can reduce the mutual attraction between particles and reduce aggregation, thereby improving the dispersion effect. In addition, the presence of the liquid phase can reduce friction during the mixing process, making the particles easier to move and disperse. Mixing nano-silica with other solid ingredients during the dry mixing stage can help the nano-particles form a preliminary dispersion state in the other ingredients and reduce the aggregation phenomenon during subsequent wet mixing. Dispersing aids can reduce the surface tension between particles and increase the mutual repulsion between particles, thereby preventing aggregation and improving the dispersion effect. Gradually adding liquid ingredients can ensure that nano-silica can be fully infiltrated and avoid uneven mixing caused by adding liquid all at once. Increasing the temperature can reduce the viscosity of the mixture and make the rubber more fluid, thereby promoting the mutual mixing of the ingredients and the dispersion of nano-silica, reducing the possibility of coating or agglomeration. Ultrasonic treatment can further break up possible aggregates and promote the uniform dispersion of nano-particles. This step helps to ensure the uniformity and consistency of the final mixture.

[0063] S3: Add plasticizer and vulcanizer;

[0064] After mixing well, add the bio-based plasticizer and low-temperature vulcanizer gradually. The operating temperature should be kept at 70°C and the mixing time should be 5 minutes to ensure full dispersion.

[0065] Using polylactic acid as a plasticizer can improve the low-temperature flexibility of the material, while the introduction of low-temperature vulcanizing agents (such as ammonium phosphite) ensures the activity of the vulcanization reaction within the low temperature range. This step ensures that the compound rubber can still maintain good structure and physical properties under low temperature conditions.

[0066] S4: cooling and forming;

[0067] The uniformly mixed rubber was taken out from the equipment and allowed to cool to 25°C at room temperature.

[0068] The cooled rubber mixture is molded into a mold and pressed into the desired product shape.

[0069] S5: Sulfurization treatment;

[0070] The formed rubber compound is placed in a vulcanizing furnace, the temperature is set to 180°C, and the vulcanization time is 30 minutes to ensure full vulcanization and form ideal physical properties.

[0071] Vulcanization is an important step in the formation of a three-dimensional network structure of fluororubber compounds, which greatly improves the temperature resistance, strength and elasticity of the material. The vulcanization time of 30 minutes at 180°C is determined based on material properties and previous experimental results, which helps to ensure that the vulcanization reaction is fully carried out.

[0072] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A low temperature resistant fluororubber compound, characterized by: It includes ternary polymer fluororubber 2462: 100-105 parts, magnesium oxide 150: 5-10 parts, calcium hydroxide: 6-10 parts, wollastonite: 20-26 parts, diatomaceous earth 499: 15-20 parts, colorant: 3-5 parts, adhesive carbon fiber: 15-18 parts, RL-28: 3-6 parts, accelerator BPP: 0.6-1 parts, bisphenol AF: 2-5 parts, nano silicon dioxide: 2-5 parts, low temperature vulcanizer 3-5 parts and bio-based plasticizer 3-5 parts.

2. The low temperature resistant fluororubber compound according to claim 1, characterized in that: The colorant is aniline black, azo dye and the like.

3. The low temperature resistant fluororubber compound according to claim 2, characterized in that: The low-temperature vulcanizing agent is ammonium phosphite, and the bio-based plasticizer is polylactic acid.

4. The method for preparing a low-temperature resistant fluororubber compound according to claim 3, characterized in that: The following steps are involved: S1: prepare raw materials; S2: pre-treated nano-silica; S3: Add plasticizer and vulcanizer; S4: cooling and forming; S5: Vulcanization treatment.

5. The method for preparing a low-temperature resistant fluororubber compound according to claim 4, characterized in that: S1: preparing raw materials, including the following steps: S11: Prepare all raw materials in a clean laboratory environment; S12: Prepare the mixing equipment and ensure that it is cleaned and in good working condition before use. S13: Weigh all raw materials according to the above proportions to ensure accuracy.

6. The method for preparing a low-temperature resistant fluororubber compound according to claim 4, characterized in that: S2: Pre-treating nano-silicon dioxide, comprising the following steps: S21: Surface treatment: Before adding nano-silica, its surface is modified by chemical or physical methods to improve its compatibility in a specific matrix, which can be achieved by coating with organic compounds or silane treatment; Alternatively, wet dispersion is used, i.e., premixing is performed in the liquid phase, the nano-silica is premixed with the solvent, and then mixed with other ingredients; S22: Preliminary mixing: dry mixing of nano-silicon dioxide and other solid components. In this stage, high-speed stirring is used to preliminarily disperse the nano-silicon dioxide. S23: Adding dispersing aid: Adding a proper amount of dispersing aid can effectively reduce the interaction force between nanoparticles and prevent them from aggregating. S24: Wet mixing stage: Gradually add liquid ingredients: During the dry mixing process, gradually add liquid ingredients (such as fluororubber matrix, accelerator, etc.) and keep stirring to ensure that the nano-silica can be fully infiltrated. S25: Increase the mixing temperature: Properly increasing the temperature during the wet mixing process can reduce the mixing viscosity, help the material flow, and promote uniform dispersion. S26: Using ultrasonic treatment: After the mixing is completed, the mixture can be subjected to ultrasonic treatment for 5-10 minutes to further improve the dispersion effect.

7. The method for preparing a low-temperature resistant fluororubber compound according to claim 4, characterized in that: S3: Adding plasticizer and vulcanizer, including the following steps: After mixing well, add the bio-based plasticizer and low-temperature vulcanizer gradually. The operating temperature should be kept at 70°C and the mixing time should be 5 minutes to ensure full dispersion.

8. The method for preparing a low-temperature resistant fluororubber compound according to claim 4, characterized in that: S4: Cooling and forming, including the following steps: The uniformly mixed rubber was taken out from the equipment and allowed to cool to 25°C at room temperature. The cooled rubber mixture is molded into a mold and pressed into the desired product shape.

9. The method for preparing a low-temperature resistant fluororubber compound according to claim 4, characterized in that: S5: Sulfurization treatment, including the following steps: The formed rubber compound is placed in a vulcanizing furnace, the temperature is set to 180°C, and the vulcanization time is 30 minutes to ensure full vulcanization and form ideal physical properties.

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