Preparation method of magnesium-zinc composite heat stabilizer

Abstract

The invention relates to the technical field of heat stabilizer preparation, and discloses a preparation method of a magnesium-zinc composite heat stabilizer, and the preparation method comprises the following steps: S1, raw material pretreatment, S2, constant-temperature mixing stirring, S3, reaction monitoring and regulation stirring, S4, product post-treatment, and S5, drying and packaging, the method is efficient and stable, and the performance is excellent; the heat stabilizer shows excellent heat stability, can effectively inhibit the thermal degradation reaction of a polymer and prolong the service life of a product in the processing and using processes of rubber and plastic, and can play a stabilizing role in a wider temperature range compared with a traditional heat stabilizer, so that the service life of the product is prolonged. According to the magnesium-zinc composite heat stabilizer, lead salt and other toxic components are completely abandoned, zinc stearate, magnesium stearate and other environment-friendly raw materials are adopted, and harm to human health and the environment is eliminated from the source.

Description

Technical Field

[0001] The present invention relates to the technical field of the preparation of heat stabilizers, and specifically to a preparation method of a magnesium-zinc composite heat stabilizer. Background Art

[0002] In the production and processing fields of rubber and plastics, heat stabilizers are indispensable important additives, and their performance directly affects the quality and application value of products. At present, the heat stabilizers widely used in the market mainly include products such as lead salts, methyl tin, zinc oxide, calcium zinc, etc. However, these traditional heat stabilizers have many defects that cannot be ignored.

[0003] In terms of heat stability performance, the existing heat stabilizers have limited ability to inhibit the degradation of rubber and plastics due to heat, resulting in problems such as performance deterioration and accelerated aging of products during high-temperature processing or long-term use. In terms of colorability, they cannot provide good color stability for products, resulting in the color of products being easily affected by processing conditions and environmental factors and changing, making it difficult to meet application scenarios with high color requirements.

[0004] In actual production, the existing heat stabilizers often need to be added in large amounts to achieve a certain stabilizing effect, which not only significantly increases the production cost but also may affect other properties of the products. More seriously, heat stabilizers such as lead salts have high toxicity and will cause potential harm to human health and the ecological environment during production, use, and waste treatment. With the increasingly strict environmental protection standards, their applications are increasingly restricted. In addition, the products produced using these heat stabilizers have low gloss, which affects the appearance quality and market competitiveness of the products. These problems greatly limit the quality improvement and application expansion of rubber and plastic products, and there is an urgent need to develop a heat stabilizer with better performance. Summary of the Invention

[0005] (1) Technical Problems to be Solved

[0006] Aiming at the deficiencies of the prior art, the present invention provides a preparation method of a magnesium-zinc composite heat stabilizer, which has the advantages of high efficiency, stability, and excellent performance, and solves the problems that the existing heat stabilizers have limited ability to inhibit the degradation of rubber and plastics due to heat, resulting in performance deterioration and accelerated aging of products during high-temperature processing or long-term use.

[0007] (2) Technical Solutions

[0008] To achieve the above-mentioned purpose of high efficiency, stability, and excellent performance, the present invention provides the following technical solutions: a preparation method of a magnesium-zinc composite heat stabilizer, including S1 raw material pretreatment, S2 constant-temperature mixing and stirring, S3 reaction monitoring and regulation, S4 product post-treatment, and S5 drying and packaging. The S1 raw material pretreatment: According to the precise ratios of Example 1 (60 g of zinc stearate, 20 g of magnesium stearate, 8 g of calcium stearate, 2 g of stearic acid, 12 g of nano-light calcium carbonate) and Example 2 (52 g of zinc stearate, 30 g of magnesium stearate, 3 g of calcium stearate, 5 g of stearic acid, 10 g of nano-light calcium carbonate), use an electronic balance with an accuracy of 0.01 g to weigh the raw materials.

[0009] The purity of the raw materials needs to be strictly controlled. The purity of zinc stearate, magnesium stearate, and calcium stearate should not be less than 99%, the purity of stearic acid should not be less than 98%, and the purity of nano-light calcium carbonate should not be less than 99.5%. If the raw materials show agglomeration, use a pulverizer to crush them to a particle size less than 100 mesh; if there are impurities, use a 150-mesh sieve for screening to ensure the uniformity and appropriate particle size of the raw materials, laying a foundation for the full progress of the subsequent mixing reaction.

[0010] Preferably, in the S2 constant-temperature mixing and stirring: Add the weighed raw materials successively into a 500-mL stainless-steel reaction kettle with a stirring device. The reaction kettle is equipped with a high-precision temperature control system. Set the temperature precisely to 25 ± 1 °C and keep it constant. Turn on the stirring device. The stirring paddle is a double-layer inclined blade paddle type. The initial stirring speed is set to 180 r / min. Within the first 30 minutes after the start of stirring, detect the temperature and mixing uniformity of the materials in the reaction kettle every 10 minutes.

[0011] Use a thermometer to measure the material temperature to ensure that the temperature fluctuation does not exceed ±1 °C; Observe the color and particle distribution uniformity of the material by sampling. If it is found to be uneven, appropriately adjust the stirring speed, but not exceeding 220 r / min at most.

[0012] Preferably, in the S3 reaction monitoring and regulation: During the stirring reaction, take out 5 g of samples from the reaction kettle every 30 minutes for analysis. Use a Fourier transform infrared spectrometer (FT-IR) to detect the samples. The scanning range is 400 - 4000 cm-1, and the resolution is 4 cm-1. By comparing with the standard spectrum, monitor the reaction degree of the raw materials and the composition changes of the products.

[0013] Preferably, in the S4 product post-treatment: After the reaction ends, filter the product in the reaction kettle through a stainless-steel filter screen with a pore size of 5 μm to remove particle impurities with a particle size greater than 5 μm. Then, transfer the filtered product to a centrifuge for centrifugal separation. The centrifuge speed is set to 3000 r / min, and the centrifugation time is 15 minutes to further separate possible fine impurities and improve the purity of the product.

[0014] Preferably, for S5 drying and packaging: The heat stabilizer product after separation treatment contains a certain amount of moisture. It is placed in a vacuum drying oven for drying. The vacuum degree in the drying oven is controlled at -0.095 to -0.1 MPa, the temperature is set at 45 ± 2 °C, and the drying time is determined according to the initial moisture content of the product. If the initial moisture content is between 10% and 15%, the drying time is 5 hours.

[0015] Preferably, for S5 drying and packaging: If the initial moisture content is between 5% and 10%, the drying time is 4 hours. The moisture content of the product is detected by a moisture analyzer every 1 hour until the moisture content of the product is lower than 2%. The dried heat stabilizer is sealed and packaged with an aluminum foil bag. The packaging weight of each bag is 1 kg. The product name, ingredients, production date, and shelf life information are marked on the package to prevent it from contacting moisture and oxygen substances in the air, which may affect its performance and stability.

[0016] Preferably, for S3 reaction monitoring and regulation, if it is found that the reaction of zinc stearate or magnesium stearate is incomplete, the stirring speed can be increased by 10 - 20 r / min; if the proportion deviation of some components in the product exceeds 5%, the corresponding raw materials are appropriately supplemented according to the deviation situation, and the stirring time is extended by 0.5 - 1 hour to ensure that the reaction proceeds in the direction of generating the target heat stabilizer.

[0017] Preferably, for S2 constant temperature mixing and stirring, continuous stirring is carried out for 2.5 hours. During the stirring process, the components of zinc stearate and magnesium stearate react due to their own physical and chemical properties and gradually form a stable composite system.

[0018] (III) Beneficial effects

[0019] Compared with the prior art, the present invention provides a preparation method of a magnesium-zinc composite heat stabilizer, which has the following beneficial effects:

[0020] 1. The preparation method of the magnesium-zinc composite heat stabilizer is efficient, stable, and has excellent performance: Through unique formulation design and preparation process, this heat stabilizer exhibits excellent heat stability performance. During the processing and use of rubber and plastics, it can effectively inhibit the thermal degradation reaction of polymers and extend the service life of products. Compared with traditional heat stabilizers, it can play a stabilizing role in a wider temperature range, enabling products to maintain good physical and chemical stability in high-temperature environments.

[0021] 2. The preparation method of the magnesium-zinc composite heat stabilizer is environmentally friendly, non-toxic, safe and reliable: This magnesium-zinc composite heat stabilizer completely abandons the toxic components of lead salts and adopts environmentally friendly raw materials such as zinc stearate and magnesium stearate, eliminating the harm to human health and the environment from the source. During the production and use process, no toxic or harmful substances will be released, meeting the requirements of current strict environmental protection regulations and providing strong support for the green and sustainable development of the rubber and plastic industries.

[0022] 3. The preparation method of the magnesium-zinc composite heat stabilizer uses less and has a low cost: Thanks to its efficient stabilization mechanism, when achieving the same stabilization effect, the required addition amount of this heat stabilizer is much lower than that of traditional heat stabilizers. This means that during the production process, enterprises can significantly reduce the procurement cost of heat stabilizers, while reducing the negative impact on product performance caused by the large addition of additives, achieving a double optimization of cost and performance.

[0023] 4. The preparation method of the magnesium-zinc composite heat stabilizer improves the comprehensive quality of products: On the one hand, this heat stabilizer has good coloring properties, ensuring that the colors of rubber and plastic products are stable and bright during processing and use, meeting the strict requirements of the high-end market for the appearance colors of products. On the other hand, the products produced using this heat stabilizer have high gloss, significantly enhancing the appearance texture of the products and strengthening their competitiveness in the market. In addition, the products also have good heat resistance, weather resistance and flexibility, enabling them to perform excellently in different use environments and application scenarios, and broadening the application fields of rubber and plastic products. Specific embodiments

[0024] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0025] S1 Raw material pretreatment: According to the precise ratios of Example 1 (60 g of zinc stearate, 20 g of magnesium stearate, 8 g of calcium stearate, 2 g of stearic acid, 12 g of nano light calcium carbonate) and Example 2 (52 g of zinc stearate, 30 g of magnesium stearate, 3 g of calcium stearate, 5 g of stearic acid, 10 g of nano light calcium carbonate), use an electronic balance with a precision of 0.01 g to weigh the raw materials;

[0026] The purity of raw materials needs to be strictly controlled. The purity of zinc stearate, magnesium stearate, and calcium stearate should not be less than 99%, the purity of stearic acid should not be less than 98%, and the purity of nano light calcium carbonate should not be less than 99.5%. If the raw materials show caking, use a pulverizer to crush them to a particle size less than 100 mesh; if there are impurities, use a 150-mesh sieve for screening to ensure the uniformity and appropriate particle size of the raw materials, laying a foundation for the full progress of subsequent mixing reactions;

[0027] S2 Constant temperature mixing and stirring: Add the weighed raw materials to a 500 mL stainless steel reaction kettle with a stirring device in sequence. The reaction kettle is equipped with a high-precision temperature control system. Set the temperature accurately to 25 ± 1 °C and keep it constant. Turn on the stirring device. The stirring paddle is a double-layer inclined blade type. The initial stirring speed is set to 180 r / min. Within the first 30 minutes after the start of stirring, detect the temperature and mixing uniformity of the materials in the reaction kettle every 10 minutes;

[0028] Use a thermometer to measure the material temperature to ensure that the temperature fluctuation does not exceed ±1 °C; Observe the color and particle distribution uniformity of the materials by sampling. If it is found to be uneven, appropriately adjust the stirring speed, but the maximum does not exceed 220 r / min;

[0029] Continue stirring for 2.5 hours. During the stirring process, the components of zinc stearate and magnesium stearate react due to their own physical and chemical properties and gradually form a stable composite system;

[0030] S3 Reaction monitoring and regulation: During the stirring reaction process, take out 5 g of samples from the reaction kettle every 30 minutes for analysis. Use a Fourier transform infrared spectrometer (FT-IR) to detect the samples. The scanning range is 400 - 4000 cm-1, and the resolution is 4 cm-1. By comparing with the standard spectrum, monitor the reaction degree of the raw materials and the composition changes of the products;

[0031] If it is found that the reaction of zinc stearate or magnesium stearate is incomplete, the stirring speed can be increased by 10 - 20 r / min; if the proportion deviation of some components in the product exceeds 5%, then appropriately supplement the corresponding raw materials according to the deviation situation and extend the stirring time by 0.5 - 1 hour to ensure that the reaction proceeds in the direction of generating the target heat stabilizer;

[0032] S4 Product post-treatment: After the reaction is completed, filter the product in the reaction kettle through a stainless steel filter screen with a pore size of 5 μm to remove particle impurities with a particle size greater than 5 μm. Then, transfer the filtered product to a centrifuge for centrifugal separation. The centrifuge speed is set to 3000 r / min, and the centrifugation time is 15 minutes to further separate possible fine impurities and improve the purity of the product;

[0033] S5 Drying and Packaging: The heat stabilizer product after separation treatment contains a certain amount of moisture. It is placed in a vacuum drying oven for drying. The vacuum degree in the drying oven is controlled at -0.095 - -0.1 MPa, the temperature is set at 45 ± 2 °C, and the drying time is determined according to the initial moisture content of the product. If the initial moisture content is between 10% - 15%, the drying time is 5 hours;

[0034] If the initial moisture content is between 5% - 10%, the drying time is 4 hours. The moisture content of the product is detected every 1 hour using a moisture analyzer until the moisture content of the product is lower than 2%. The dried heat stabilizer is sealed and packaged in an aluminum foil bag, with each bag weighing 1 kg. The product name, composition, production date, and shelf life information are marked on the package to prevent it from contacting moisture and oxygen in the air, which may affect its performance and stability.

[0035] Furthermore, this method is environmentally friendly, non-toxic, safe and reliable: This magnesium-zinc composite heat stabilizer completely abandons toxic components such as lead salts and uses environmentally friendly raw materials such as zinc stearate and magnesium stearate, eliminating the harm to human health and the environment from the source. During the production and use process, no toxic and harmful substances will be released, meeting the requirements of current strict environmental protection regulations and providing strong support for the green and sustainable development of the rubber and plastic industries;

[0036] Furthermore, this method is efficient, stable and has excellent performance: Through unique formulation design and preparation process, this heat stabilizer exhibits excellent heat stability performance. During the processing and use of rubber and plastics, it can effectively inhibit the thermal degradation reaction of polymers and extend the service life of products. Compared with traditional heat stabilizers, it can play a stabilizing role in a wider temperature range, enabling products to maintain good physical and chemical stability in high-temperature environments;

[0037] Furthermore, this method uses less and has a lower cost: Relying on its efficient stabilization mechanism, when this heat stabilizer achieves the same stabilization effect, the required addition amount is much lower than that of traditional heat stabilizers. This means that during the production process, enterprises can significantly reduce the procurement cost of heat stabilizers and at the same time reduce the negative impact on product performance caused by the large addition of additives, achieving a double optimization of cost and performance;

[0038] Furthermore, this method improves the comprehensive quality of products: On the one hand, this heat stabilizer has good coloring properties, which can ensure that the colors of rubber and plastic products are stable and bright during processing and use, meeting the strict requirements of the high-end market for the appearance colors of products. On the other hand, the products produced using this heat stabilizer have high gloss, significantly improving the appearance texture of the products and enhancing the competitiveness of the products in the market. In addition, the products also have good heat resistance, weather resistance and flexibility, enabling them to perform well in different use environments and application scenarios, and broadening the application fields of rubber and plastic products.

[0039] Although embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a magnesium-zinc composite heat stabilizer, comprising S1 raw material pretreatment, S2 constant temperature mixing and stirring, S3 reaction monitoring and control stirring, S4 product post-treatment and S5 drying and packaging, characterized in that: The S1 raw material pretreatment: according to the precise ratio of Example 1 (60g zinc stearate, 20g magnesium stearate, 8g calcium stearate, 2g stearic acid, 12g nano light calcium carbonate) and Example 2 (52g zinc stearate, 30g magnesium stearate, 3g calcium stearate, 5g stearic acid, 10g nano light calcium carbonate), the raw materials were weighed using an electronic balance with an accuracy of 0.01g; The purity of the raw materials must be strictly controlled. The purity of zinc stearate, magnesium stearate, and calcium stearate should be no less than 99%, the purity of stearic acid should be no less than 98%, and the purity of nano-light calcium carbonate should be no less than 99.5%. If the raw materials are agglomerated, use a grinder to crush them to a particle size of less than 100 mesh; if there are impurities, use a 150-mesh sieve to screen them to ensure the uniformity and appropriate particle size of the raw materials, laying the foundation for the subsequent mixing reaction to proceed fully.

2. The method for preparing the magnesium-zinc composite heat stabilizer according to claim 1, characterized in that: The S2 constant temperature mixing and stirring: the weighed raw materials are added in sequence into a stainless steel reactor with a volume of 500 mL and a stirring device. The reactor is equipped with a high-precision temperature control system. The temperature is accurately set to 25±1°C and maintained at a constant temperature. The stirring device is turned on. The stirring paddle adopts a double-layer inclined blade paddle type. The stirring speed is initially set to 180r / min. Within the first 30 minutes after the stirring starts, the temperature and mixing uniformity of the materials in the reactor are tested every 10 minutes; Use a thermometer to measure the material temperature and ensure that the temperature fluctuation does not exceed ±1°C; observe the color and particle distribution uniformity of the material by sampling. If unevenness is found, adjust the stirring speed appropriately, but the maximum speed shall not exceed 220r / min.

3. The method for preparing the magnesium-zinc composite heat stabilizer according to claim 1, characterized in that: The S3 reaction monitoring and control: During the stirring reaction, 5 g of sample was taken out from the reactor every 30 minutes for analysis, and the sample was detected by Fourier transform infrared spectrometer (FT-IR) with a scanning range of 400-4000 cm-1 and a resolution of 4 cm-1. By comparing with the standard spectrum, the reaction degree of the raw materials and the composition changes of the products were monitored.

4. The method for preparing the magnesium-zinc composite heat stabilizer according to claim 1, characterized in that: The S4 product post-treatment: After the reaction is completed, the product in the reactor is filtered through a stainless steel filter with a pore size of 5 μm to remove particulate impurities with a particle size greater than 5 μm, and then the filtered product is transferred to a centrifuge for centrifugal separation. The centrifuge speed is set to 3000 r / min and the centrifugation time is 15 minutes to further separate possible fine impurities and improve the purity of the product.

5. The method for preparing the magnesium-zinc composite heat stabilizer according to claim 1, characterized in that: The S5 drying and packaging: the heat stabilizer product after separation contains a certain amount of water, which is placed in a vacuum drying oven for drying. The vacuum degree in the drying oven is controlled at -0.095--0.1MPa, and the temperature is set to 45±2°C. The drying time is determined according to the initial water content of the product. If the initial water content is between 10% and 15%, the drying time is 5 hours.

6. The method for preparing the magnesium-zinc composite heat stabilizer according to claim 5, characterized in that: The S5 drying and packaging: if the initial moisture content is between 5% and 10%, the drying time is 4 hours, and the moisture content of the product is detected by a moisture meter every hour until the moisture content of the product is less than 2%. The dried heat stabilizer is sealed and packaged in an aluminum foil bag, and the weight of each bag is 1 kg. The product name, ingredients, production date, and shelf life information are marked on the package to prevent it from contacting with moisture and oxygen in the air, which may affect its performance and stability.

7. The method for preparing the magnesium-zinc composite heat stabilizer according to claim 3, characterized in that: The S3 reaction monitoring and control, if it is found that the reaction of zinc stearate or magnesium stearate is incomplete, the stirring speed can be increased by 10-20r / min; if the deviation of the proportion of certain components in the product exceeds 5%, the corresponding raw materials are appropriately supplemented according to the deviation, and the stirring time is extended by 0.5-1 hour to ensure that the reaction proceeds in the direction of generating the target thermal stabilizer.

8. The method for preparing the magnesium-zinc composite heat stabilizer according to claim 2, characterized in that: The S2 is mixed and stirred at a constant temperature for 2.5 hours. During the stirring process, the zinc stearate and magnesium stearate components react due to their own physical and chemical properties to gradually form a stable composite system.