Preparation method and preparation control system of degradable plastic modified liquid silica gel

Abstract

The invention belongs to the technical field of material preparation, and particularly relates to a preparation method of degradable plastic modified liquid silica gel and a preparation control system of the degradable plastic modified liquid silica gel. The electrical properties of the material are effectively controlled and optimized by using a series of fine regulation and control steps such as dropwise adding of an organic silicon pre-crosslinking agent under the protection of nitrogen, treatment of an alternating electromagnetic field, pH adjustment and curing of an initiator. The method not only solves the problem that the electrical property is difficult to accurately control in the prior art, but also remarkably improves the overall performance of the material, so that the material has higher dielectric constant and lower conductivity, and meanwhile, keeps good mechanical property. Finally, the material prepared by the method can better meet the application fields with relatively high requirements on electrical properties, such as high-performance electronic equipment packaging and sensor manufacturing.

Description

Technical Field

[0001] The invention belongs to the technical field of material preparation, and in particular relates to a preparation method of biodegradable plastic modified liquid silica gel and a preparation control system thereof. Background Art

[0002] At present, the preparation methods of biodegradable plastic modified liquid silicone mainly focus on improving the mechanical properties and environmental friendliness of the materials by adding various fillers (such as nanoparticles, fibers, etc.). However, these methods have certain limitations in controlling and optimizing the electrical properties of the materials. Existing technologies usually use simple physical mixing or chemical cross-linking methods to prepare composite materials, but these methods often have difficulty in accurately regulating the dielectric constant and conductivity of the materials, resulting in limited applicability in specific application scenarios.

[0003] For example, some existing technologies improve the conductivity by adding conductive fillers (such as carbon black or metal powder) to silica gel, but this method easily causes uneven distribution of fillers, affecting the overall performance of the material. In addition, the traditional preparation process lacks the application of advanced methods such as electromagnetic field treatment, and cannot effectively improve the dielectric properties and stability of the material.

[0004] The main problem with existing technologies is that it is difficult to accurately control and optimize the electrical properties (such as dielectric constant and conductivity) of materials while maintaining their mechanical properties to meet the needs of specific application scenarios. Especially in the fields of high-demand electronic equipment packaging, sensors, etc., the electrical properties of materials directly affect the performance and reliability of the final product. Summary of the invention

[0005] The object of the present invention is to provide a method for preparing a biodegradable plastic modified liquid silica gel and a preparation control system thereof, which can effectively control and optimize the electrical properties of the material to solve the problems raised in the above background technology.

[0006] To achieve the above object, the present invention provides a method for preparing a biodegradable plastic modified liquid silica gel, comprising the following steps:

[0007] S1: mixing the biodegradable plastic and liquid silicone in a mass ratio of 1:3, and subjecting the mixture to ultrasonic treatment to form a premix;

[0008] S2: adding 4-5% of the total amount of carbon nanotubes to the premix, and stirring at 200-400 rpm for 14-16 minutes;

[0009] S3: adding 0.7-0.9 mol / L of organosilicon pre-crosslinking agent dropwise to the mixture under nitrogen protection, maintaining the temperature at 50-70° C. for reaction for 20-40 minutes to obtain a reaction product;

[0010] S4: applying an alternating electromagnetic field with a frequency of 40-60 kHz and an intensity of 0.4-0.6 T to the reaction product for 9-11 minutes, adjusting the pH to 8-9, adding 0.1-0.2 wt % of ammonium persulfate initiator, and curing at 60-80° C. for 40-50 minutes to obtain a cured product;

[0011] S5: heat treating the solidified material at 70-90° C. for 1-3 hours, and then cooling it to room temperature to obtain a sample. The dielectric constant of the sample is tested to be in the range of 12-13, and the conductivity is at the level of 10^-5S / cm;

[0012] S6: Repeat steps S2-S5 according to the test results until a material with a dielectric loss tangent value less than 0.03 is obtained.

[0013] Preferably, the biodegradable plastic and liquid silica gel are mixed in a mass ratio of 1:3 and subjected to ultrasonic treatment to form a premix, comprising:

[0014] Weigh the degradable plastic and liquid silicone to make a mass ratio of 1:3, and record the masses m1 and m2, where m1 is the mass of the degradable plastic and m2 is the mass of the liquid silicone;

[0015] Place the degradable plastic in a clean container, add the liquid silica gel, and ensure that the mass of the mixture satisfies the formula M=m1+m2, where M is the total mass of the mixture;

[0016] Using a high-speed stirrer to preliminarily mix the mixture at a speed of 400-600 rpm for 4-6 minutes to form a preliminary mixture;

[0017] The preliminary mixture is transferred to an ultrasonic processor, and the ultrasonic power is set to 70-90 W, the frequency is set to 30-50 kHz, and the processing time is set to 10-20 minutes to finally form a premix.

[0018] Preferably, the step of adding 4-5% of the total carbon nanotubes to the premix and stirring at 200-400 rpm for 14-16 minutes comprises:

[0019] According to the total mass M of the preliminary mixture, the mass Mc of the carbon nanotubes to be added is calculated, and the mass Mc of the carbon nanotubes is 4-5% of the total mass M;

[0020] Weighing carbon nanotubes with a mass of Mc, and slowly and evenly adding them to the preliminary mixture to form a mixed system containing carbon nanotubes;

[0021] Placing the mixed system containing carbon nanotubes in a high-speed stirrer, setting the speed to 200-400 rpm, starting the stirrer and continuing to run;

[0022] During the stirring process, the stirrer was paused every 5 minutes, and the mixing system was manually stirred with a spatula to ensure that the carbon nanotubes would not be deposited until the stirring cycle of 14-16 minutes was completed.

[0023] Preferably, 0.7-0.9 mol / L of organosilicon pre-crosslinking agent is added dropwise to the mixture under nitrogen protection, and the temperature is maintained at 50-70° C. for 20-40 minutes to obtain a reaction product, including:

[0024] According to the total volume of the mixed system V = M + Mc, calculate the required volume of 0.7-0.9 mol / L organosilicon pre-crosslinking agent to ensure that it accounts for 10% of the total volume of the mixed system, that is, Vp = 0.1*V, where Vp is the volume of the pre-crosslinking agent;

[0025] The mixed system is transferred to a reactor equipped with a nitrogen protection device, and the nitrogen flow is turned on to place the mixed system under a nitrogen protection environment;

[0026] Under the condition of keeping the nitrogen flow rate constant, using a microinjection pump to dropwise add a volume of Vp of the organosilicon pre-crosslinking agent into the mixed system at a rate of Vp / 30 per minute;

[0027] After the dropwise addition is completed, the temperature of the reactor is adjusted to 50-70° C. and maintained, and a timer is started to record the reaction time to ensure that the reaction lasts for 20-40 minutes to obtain the reaction product.

[0028] Preferably, the step of applying an alternating electromagnetic field having a frequency of 40-60 kHz and an intensity of 0.4-0.6 T to the reaction product for 9-11 minutes comprises:

[0029] Transferring the reaction product into a non-magnetic container, and placing the non-magnetic container in a working area of ​​an alternating electromagnetic field device;

[0030] Setting the parameters of the alternating electromagnetic field device so that its output frequency is 40-60kHz and the intensity is 0.4-0.6T;

[0031] The alternating electromagnetic field device is started to apply an alternating electromagnetic field with a frequency of 40-60 kHz and an intensity of 0.4-0.6 T to the reaction product, and a timer is used to record the time to ensure that the treatment lasts for 9-11 minutes.

[0032] Preferably, the pH is adjusted to 8-9, 0.1-0.2 wt% of ammonium persulfate initiator is added, and the solidified product is obtained at 60-80° C. for 40-50 minutes, comprising:

[0033] The mass Ma of the required pH adjuster is determined using the formula Ma=V*Ca*10^-3, where Ca is the concentration of the pH adjuster;

[0034] Transferring the reaction product to a container with a stirring device, slowly adding a calculated amount of a pH adjuster, and continuously stirring until the pH value of the reaction product reaches 8-9;

[0035] After the pH value of the reaction product stabilizes at 8-9, weigh 0.1-0.2 wt% of the total mass of the reaction product as ammonium persulfate initiator, sprinkle it evenly into the reaction product, and continue stirring for 4-6 minutes;

[0036] Then the mixture is moved to a curing oven preheated to 60-80° C., and a curing treatment is performed for 40-50 minutes while maintaining a constant temperature to obtain the cured product.

[0037] Preferably, the solidified material is subjected to heat treatment at 70-90° C. for 1-3 hours and then rapidly cooled to room temperature to obtain a sample, comprising:

[0038] The solidified product is taken out of the curing oven and quickly transferred to a heat treatment device with a preset temperature of 70-90°C;

[0039] The cured product is subjected to a heat treatment at 70-90° C. in the heat treatment equipment for a duration of 1-3 hours;

[0040] After the heat treatment is completed, the solidified material is immediately taken out from the heat treatment equipment and quickly placed in a cooling device, and the solidified material is rapidly cooled to room temperature by quenching. The cooling rate Vc can be calculated according to the formula Vc=(Ti-Tf) / Tc, where Ti is the initial temperature, Tf is the final temperature room temperature, and Tc is the cooling time;

[0041] After the solidified material is completely cooled to room temperature, a sample is obtained.

[0042] Preferably, the test of the sample dielectric constant to a range of 12-13, the conductivity to a level of 10^-5S / cm, includes:

[0043] The sample is cut into a standard test size to ensure that its thickness D and area A meet the requirements of the test equipment, and the capacitance value C is calculated using the formula C=ε*A / D, where ε is the target dielectric constant 12-13;

[0044] Install the sample in a test fixture of a dielectric constant tester and connect the measuring circuit;

[0045] Start the dielectric constant tester, apply a specified voltage to the sample, and record the measured capacitance value C;

[0046] After completing the dielectric constant test, the sample is transferred to a conductivity tester to start the test, and the conductivity value σ of the sample is recorded to ensure that it is at the level of 10^-5S / cm.

[0047] Preferably, repeating steps S2-S5 according to the test results until a material with a dielectric loss tangent value less than 0.03 is obtained comprises:

[0048] According to the test results of the sample, the dielectric loss tangent value Tanδ is recorded. If Tanδ is greater than 0.03, the formula or process parameters need to be adjusted;

[0049] Calculate the new amount of carbon nanotubes added Mc' using the formula Mc' = Mc*(1+Δ%), where Δ% is the adjustment ratio;

[0050] Use a new amount of carbon nanotubes Mc' to re-prepare the mixed system, and ensure that the mass of the mixed system satisfies the formula M'=m1+m2+Mc', where M' is the total mass of the new mixed system;

[0051] The new mixed system is sequentially subjected to crosslinking agent addition, electromagnetic field treatment, pH adjustment, initiator addition, curing and heat treatment operations to obtain a new sample;

[0052] Test the new sample and record the new dielectric constant, conductivity and dielectric loss tangent value Tanδ';

[0053] Compare the dielectric loss tangent value Tanδ' of the new sample with the target value 0.03. If the requirement is still not met, adjust the amount of carbon nanotubes added again and repeat the test until the dielectric loss tangent value is less than 0.03.

[0054] On the other hand, the present invention provides a preparation control system for biodegradable plastic modified liquid silicone, comprising:

[0055] A premix preparation module is used to mix the biodegradable plastic and liquid silicone in a mass ratio of 1:3 and form a premix by ultrasonic treatment;

[0056] A carbon nanotube adding module, used for adding 4-5% of the carbon nanotubes to the premix, and stirring at 200-400 rpm for 14-16 minutes;

[0057] An organic silicon pre-crosslinking agent dropping module is used to drop 0.7-0.9 mol / L of organic silicon pre-crosslinking agent into the mixture under nitrogen protection, maintain the temperature at 50-70° C. for 20-40 minutes to obtain a reaction product;

[0058] A solidified product preparation module is used to apply an alternating electromagnetic field with a frequency of 40-60kHz and an intensity of 0.4-0.6T to the reaction product for 9-11 minutes, adjust the pH to 8-9, add 0.1-0.2wt% ammonium persulfate initiator, and cure at 60-80°C for 40-50 minutes to obtain a solidified product;

[0059] A test module, used for heat treating the solidified material at 70-90°C for 1-3 hours, and then cooling it to room temperature to obtain a sample, and testing the dielectric constant of the sample to be within the range of 12-13, and the conductivity to be at the level of 10^-5S / cm;

[0060] The optimization cycle module is used to repeat the preparation steps according to the test results until a material with a dielectric loss tangent value less than 0.03 is obtained.

[0061] Technical effects and advantages of the present invention: Compared with the prior art, the preparation method of the biodegradable plastic modified liquid silica gel and the preparation control system thereof proposed by the present invention have the following advantages:

[0062] The present invention ensures the uniform distribution of carbon nanotubes in the matrix through ultrasonic treatment and high-speed stirring, and effectively controls and optimizes the electrical properties of the material by a series of fine-tuning steps such as adding a pre-crosslinking agent of organic silicon under nitrogen protection, treating with an alternating electromagnetic field, adjusting pH, and curing with an initiator. This method not only solves the problem of the difficulty in accurately controlling electrical properties in the prior art, but also significantly improves the overall performance of the material, making it have a higher dielectric constant and lower conductivity, while maintaining good mechanical properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 This is a flow chart of a method for preparing a degradable plastic-modified liquid silica gel according to the present invention;

[0064] Figure 2 The present invention is a block diagram of a system for preparing biodegradable plastic-modified liquid silica gel. DETAILED DESCRIPTION

[0065] The following will be combined with the accompanying 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, rather than all the embodiments. The specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0066] Example 1

[0067] The present invention provides Figure 1 The method for preparing a biodegradable plastic modified liquid silica gel is characterized by comprising the following steps:

[0068] S1: mixing the biodegradable plastic and liquid silicone in a mass ratio of 1:3, and subjecting the mixture to ultrasonic treatment to form a premix; specifically comprising:

[0069] Weigh the degradable plastic and liquid silicone to a mass ratio of 1:3, and record the masses m1 and m2, where m1 is the mass of the degradable plastic and m2 is the mass of the liquid silicone; by accurately weighing the degradable plastic (mass m1) and the liquid silicone (mass m2), ensure that the two are mixed in a mass ratio of 1:3, thereby ensuring the uniformity and consistency of the matrix material. Accurately recording the mass of each component helps adjust and optimize the subsequent process parameters and ensure that each batch of prepared materials has the same initial conditions.

[0070] Place the biodegradable plastic in a clean container, add the liquid silica gel, and ensure that the mass of the mixture satisfies the formula M=m1+m2, where M is the total mass of the mixture; this step ensures that no foreign impurities are introduced during the mixing process, maintains the purity and stability of the mixture, and provides high-quality basic materials for subsequent steps.

[0071] The mixture is preliminarily mixed with a high-speed stirrer at a speed of 400-600 rpm for 4-6 minutes to form a preliminary mixture; high-speed stirring can quickly break the agglomeration between particles, promote the preliminary uniform dispersion of the two materials, and provide a more uniform base material for subsequent ultrasonic treatment. This step significantly improves the mixing efficiency and uniformity, and reduces the time and difficulty of subsequent processing.

[0072] The preliminary mixture is transferred to an ultrasonic processor, and the ultrasonic power is set to 70-90W, the frequency is 30-50kHz, and the processing time is 10-20 minutes to finally form a premix. Ultrasonic treatment can further refine the particle size, make the carbon nanotubes and other components more evenly distributed in the matrix, and significantly improve the microstructural consistency and electrical properties of the material. Ultrasonic treatment can also remove bubbles in the mixture, reduce defects, and improve the overall quality and performance of the material.

[0073] S2: adding 4-5% of the total carbon nanotubes to the premix, stirring at 200-400 rpm for 14-16 minutes; specifically comprising:

[0074] According to the total mass M of the preliminary mixture, the mass Mc of the carbon nanotubes to be added is calculated, and the mass Mc of the carbon nanotubes is 4-5% of the total mass M; accurate calculation of the mass of the carbon nanotubes helps to ensure their uniform distribution in the mixed system and the consistency of the electrical properties of the final material. Through strict quantitative control, the performance instability caused by excessive or insufficient carbon nanotubes can be avoided.

[0075] Weigh Mc of carbon nanotubes and slowly and evenly add them to the preliminary mixture to form a mixed system containing carbon nanotubes; slowly and evenly adding carbon nanotubes can prevent them from agglomerating during the mixing process, thereby improving the uniformity of subsequent dispersion. This step provides a uniform basis for subsequent stirring and ensures the initial uniform distribution of carbon nanotubes in the entire system.

[0076] The mixed system containing carbon nanotubes is placed in a high-speed stirrer, the speed is set to 200-400 rpm, and the stirrer is started and kept running; through appropriate stirring speed and time, the agglomeration phenomenon between carbon nanotubes can be effectively broken and their uniform dispersion in the matrix can be promoted. High-speed stirring not only improves the mixing efficiency, but also reduces the possibility of agglomeration, and improves the electrical properties of the final material.

[0077] During the stirring process, the stirrer was paused every 5 minutes and the mixed system was manually stirred with a scraper to ensure that the carbon nanotubes would not settle until the stirring cycle of 14-16 minutes was completed. Manual stirring can further help break up local agglomeration and ensure that the carbon nanotubes are evenly distributed throughout the mixed system to prevent them from settling at the bottom of the container.

[0078] S3: adding 0.7-0.9 mol / L of organosilicon pre-crosslinking agent to the mixture under nitrogen protection, maintaining the temperature at 50-70° C. for reaction for 20-40 minutes to obtain a reaction product; specifically comprising:

[0079] According to the total volume of the mixed system V = M + Mc, the required volume of 0.7-0.9 mol / L silicone pre-crosslinking agent is calculated to ensure that it accounts for 10% of the total volume of the mixed system, that is, Vp = 0.1*V, Vp is the volume of the pre-crosslinking agent; by strictly calculating and weighing the volume of the silicone pre-crosslinking agent, its proportion in the mixed system is ensured to be accurate, laying the foundation for subsequent reactions.

[0080] The mixed system is transferred to a reactor equipped with a nitrogen protection device, and the nitrogen flow is turned on to place the mixed system in a nitrogen protection environment; the nitrogen protection device is used to prevent the influence of oxygen on the reaction process, ensure the purity and stability of the reaction products, and improve the controllability and repeatability of the reaction.

[0081] Under the condition of keeping the nitrogen flow rate constant, a micro-injection pump is used to drop a volume of Vp of the organosilicon pre-cross-linking agent into the mixed system at a rate of Vp / 30 per minute; the organosilicon pre-cross-linking agent is added at a uniform rate using a micro-injection pump to ensure uniform reaction, avoid the problem of excessively high or low local concentration, and improve the reaction efficiency and product consistency.

[0082] After the addition is completed, the temperature of the reactor is adjusted to 50-70°C and maintained, and a timer is started to record the reaction time to ensure that the reaction lasts for 20-40 minutes to obtain the reaction product. By strictly controlling the reaction temperature and time, the organosilicon pre-crosslinking agent is ensured to fully react with other components in the mixed system to form a stable crosslinking structure, which significantly improves the structural stability and electrical properties of the final material.

[0083] S4: applying an alternating electromagnetic field with a frequency of 40-60 kHz and an intensity of 0.4-0.6 T to the reaction product for 9-11 minutes, adjusting the pH to 8-9, adding 0.1-0.2 wt % ammonium persulfate initiator, and curing at 60-80° C. for 40-50 minutes to obtain a cured product; specifically comprising:

[0084] The reaction product is transferred to a non-magnetic container, and the non-magnetic container is placed in the working area of ​​the alternating electromagnetic field device; by using a non-magnetic container and accurately setting the electromagnetic field parameters, it is ensured that the alternating electromagnetic field can act evenly on the reaction product, promoting the reorganization of molecular chains and the optimization of the internal structure of the material.

[0085] The parameters of the alternating electromagnetic field device are set so that the output frequency is 40-60kHz and the intensity is 0.4-0.6T. By precisely controlling the frequency and intensity of the electromagnetic field, the internal structure of the reaction product can be effectively optimized and stabilized. The effect of the alternating electromagnetic field helps to break the agglomeration phenomenon between molecules and promote the rearrangement of molecular chains, thereby improving the electrical and mechanical properties of the material.

[0086] The alternating electromagnetic field device is started to apply an alternating electromagnetic field with a frequency of 40-60kHz and an intensity of 0.4-0.6T to the reaction product, and a timer is used to record the time to ensure that the treatment lasts for 9-11 minutes. By strictly controlling the treatment time and electromagnetic field parameters, the reaction product is ensured to fully act in the electromagnetic field, promoting the reorganization of the molecular chain and the optimization of the internal structure of the material.

[0087] The formula Ma = V*Ca*10^-3 is used to determine the mass Ma of the required pH adjuster, where Ca is the concentration of the pH adjuster; accurate calculation and addition of the pH adjuster can ensure that the pH of the reaction system reaches the ideal range, which is crucial for the smooth progress of subsequent chemical reactions. The appropriate pH value helps promote the effective decomposition of the ammonium persulfate initiator, thereby achieving a better curing effect.

[0088] The reaction product is transferred to a container with a stirring device, and a calculated amount of pH regulator is slowly added, and stirring is continued until the pH value of the reaction product reaches 8-9; after the pH value of the reaction product is stabilized at 8-9, 0.1-0.2wt% of the total mass of the reaction product is weighed as an ammonium persulfate initiator, and evenly sprinkled into the reaction product, and stirring is continued for 4-6 minutes; ammonium persulfate, as an initiator, can decompose and generate free radicals at a suitable temperature, promote the cross-linking reaction of silica gel, and form a stable three-dimensional network structure. By evenly sprinkling and fully stirring, the uniform distribution of the initiator in the entire system is ensured, and the efficiency and uniformity of the cross-linking reaction are improved.

[0089] Then, the mixture is transferred to a curing furnace preheated to 60-80°C and cured for 40-50 minutes while maintaining a constant temperature to obtain the cured product. Strict temperature control and time management ensure that the cross-linking reaction is fully carried out to form a stable three-dimensional network structure.

[0090] S5: heat treating the solidified material at 70-90° C. for 1-3 hours, and then cooling it to room temperature to obtain a sample, and testing the dielectric constant of the sample to be in the range of 12-13, and the conductivity to be at the level of 10^-5S / cm; specifically including:

[0091] The solidified material is taken out of the curing oven and quickly transferred to a heat treatment device with a preset temperature of 70-90°C; this step ensures that the solidified material can immediately enter the heat treatment stage to avoid changes or instability in the internal structure of the material due to cooling.

[0092] The cured product is subjected to heat treatment at 70-90° C. in the heat treatment equipment for 1-3 hours; by precisely controlling the temperature and time of the heat treatment, the internal structure of the material can be further optimized, and the rearrangement of the molecular chains and the completion of the cross-linking reaction can be promoted.

[0093] After the heat treatment is completed, the solidified material is immediately taken out of the heat treatment equipment and quickly placed in a cooling device. The solidified material is rapidly cooled to room temperature by quenching. The cooling rate Vc can be calculated according to the formula Vc = (Ti-Tf) / Tc, where Ti is the initial temperature, Tf is the final room temperature, and Tc is the cooling time. The quenching treatment can prevent the material from forming an uneven crystalline structure during the cooling process, thereby maintaining the consistency of its microstructure, reducing internal stress and defects, and improving the overall performance of the material. After the solidified material is completely cooled to room temperature, a sample is obtained.

[0094] The sample is cut into standard test size, ensuring that its thickness D and area A meet the requirements of the test equipment, and the capacitance value C is calculated using the formula C = ε*A / D, where ε is the target dielectric constant of 12-13; the sample is accurately cut and its size is adjusted to ensure the accuracy and repeatability of the test results. The capacitance value C can be calculated by the formula to predict the dielectric constant of the sample, providing a reference for subsequent tests.

[0095] The sample is installed in the test fixture of the dielectric constant tester and the measuring circuit is connected; correct installation and connection ensure the stability and accuracy of signal transmission during the test and avoid external interference affecting the test results.

[0096] Start the dielectric constant tester, apply a specified voltage to the sample, and record the measured capacitance value C; by applying the specified voltage and recording the capacitance value, the dielectric constant of the sample can be accurately measured.

[0097] After the dielectric constant test is completed, the sample is transferred to the conductivity tester to start the test, and the conductivity value σ of the sample is recorded to ensure that it is at the level of 10^-5S / cm. The conductivity test further evaluates the electrical properties of the material to ensure its applicability in specific application scenarios.

[0098] S6: Repeat steps S2-S5 according to the test results until a material with a dielectric loss tangent value less than 0.03 is obtained; specifically comprising:

[0099] According to the test results of the sample, the dielectric loss tangent value Tanδ is recorded. If Tanδ is greater than 0.03, the formula or process parameters need to be adjusted. By accurately measuring and recording the dielectric loss tangent value, it is possible to accurately evaluate whether the current electrical properties of the material meet the expected requirements.

[0100] The new amount of carbon nanotubes added Mc' is calculated using the formula Mc'=Mc*(1+Δ%), where Δ% is the adjustment ratio; by adjusting the amount of carbon nanotubes added, the electrical properties of the material can be optimized in a targeted manner without affecting the ratio of other components.

[0101] The mixed system is re-prepared using a new amount of carbon nanotubes added Mc', and it is ensured that the mass of the mixed system satisfies the formula M'=m1+m2+Mc', where M' is the total mass of the new mixed system; the re-prepared mixed system ensures the consistency and uniformity of each batch of materials, providing high-quality basic materials for subsequent processing steps.

[0102] The new mixed system is subjected to the operations of cross-linking agent addition, electromagnetic field treatment, pH adjustment, initiator addition, curing and heat treatment in sequence to obtain a new sample; by repeating these key steps, it is ensured that the new batch of materials can achieve the best effect in each processing stage.

[0103] Test the new sample and record the new dielectric constant, conductivity and dielectric loss tangent Tanδ'; by comprehensively testing the electrical performance indicators of the new sample, the effect of the adjustment can be accurately evaluated. Recording detailed data helps analyze the effect of each adjustment and provides a reference for the next step of optimization.

[0104] Compare the dielectric loss tangent value Tanδ' of the new sample with the target value of 0.03. If it still does not meet the requirement, adjust the amount of carbon nanotubes added again and repeat the test until the dielectric loss tangent value is less than 0.03. Through continuous comparison and adjustment, the target performance is gradually approached. This iterative optimization method can effectively reduce the number of tests, quickly find the optimal formula and process parameters, and ensure that the final material meets the design requirements.

[0105] Example 2

[0106] Step S1: mixing the biodegradable plastic and liquid silica gel in a mass ratio of 1:3, and forming a premix by ultrasonic treatment.

[0107] The mass of degradable plastic m1 = 10g;

[0108] Liquid silica gel mass m2 = 30g;

[0109] Total mass M = m1 + m2 = 40 g;

[0110] Step S2: adding 5% of the total carbon nanotubes to the premix, and stirring at 300 rpm for 15 minutes.

[0111] The mass of carbon nanotubes Mc = 0.05 × 40 = 2 g;

[0112] Step S3: under nitrogen protection, 0.8 mol / L of organosilicon pre-crosslinking agent was added dropwise to the mixture, and the temperature was maintained at 60° C. for reaction for 30 minutes to obtain a reaction product.

[0113] Pre-crosslinking agent volume: Vp = 0.1 × 42 = 4.2 mL;

[0114] Step S4: applying an alternating electromagnetic field with a frequency of 50 kHz and an intensity of 0.5 T to the reaction product for 10 minutes, adjusting the pH to 8.5, adding 0.1 wt % ammonium persulfate initiator, and curing at 70° C. for 45 minutes to obtain a cured product.

[0115] pH adjuster mass Ma=V×Ca×10 -3 , assuming V = 42mL, Ca = 1mol / L, then Ma = 42×1×10 -3 =0.042g;

[0116] Initiator mass Mi = 0.001 × 42 = 0.042 g;

[0117] Step S5: The solidified material is subjected to a heat treatment at 80° C. for 2 hours, and then rapidly cooled to room temperature to obtain a sample. The dielectric constant of the sample is tested to be within the range of 12.5, and the conductivity is at the level of 10^-5S / cm.

[0118] Test results:

[0119] Dielectric constant: 12.5;

[0120] Conductivity: 9.8×10-69.8×10 -6 S / cm;

[0121] Dielectric loss tangent (Tanδ): 0.025;

[0122] Comparative Example 1

[0123] In order to compare the effects, a traditional method without using alternating electromagnetic field treatment and fine control process was selected as a comparative example.

[0124] Comparative ratio conditions:

[0125] Step S1: mixing the biodegradable plastic and the liquid silicone in a mass ratio of 1:3, and forming a premix by ordinary stirring.

[0126] The mass of degradable plastic m1 = 10g;

[0127] Liquid silica gel mass m2 = 30g;

[0128] Total mass M = m1 + m2 = 40 g;

[0129] Step S2: adding 5% of the total carbon nanotubes to the premix, and stirring at 300 rpm for 15 minutes.

[0130] The mass of carbon nanotubes Mc = 0.05 × 40 = 2 g;

[0131] Step S3: directly add 0.8 mol / L of organosilicon pre-crosslinking agent to the mixture, maintain the temperature at 60° C. and react for 30 minutes to obtain a reaction product.

[0132] Pre-crosslinking agent volume Vp = 0.1 × 42 = 4.2 mL;

[0133] Step S4: directly adjusting the pH to 8.5, adding 0.1 wt % ammonium persulfate initiator, and curing at 70° C. for 45 minutes to obtain a cured product.

[0134] pH adjuster mass Ma=V×Ca×10 -3, assuming V = 42mL, Ca = 1mol / L, then Ma = 42×1×10 -3 =0.042g;

[0135] Initiator mass Mi = 0.001 × 42 = 0.042 g;

[0136] Step S5: heat-treating the solidified material at 80° C. for 2 hours, and then rapidly cooling it to room temperature to obtain a sample, and testing the dielectric constant and conductivity of the sample.

[0137] Test results:

[0138] Dielectric constant: 10.5;

[0139] Conductivity: 2.5×10 -5 S / cm

[0140] Dielectric loss tangent (Tanδ): 0.045

[0141] Example 2 and comparative example results analysis and conclusion:

[0142] Dielectric Constant:

[0143] Example: 12.5;

[0144] Comparative ratio: 10.5;

[0145] Improvement: Through the method of the present invention, the dielectric constant is improved by about 19%, indicating that the electrical properties of the material have been significantly optimized.

[0146] Conductivity:

[0147] Example: 9.8×10 -6 S / cm;

[0148] Comparison ratio: 2.5×10 -5 S / cm;

[0149] Reduction: Through the method of the present invention, the conductivity is reduced by about 60.8%, indicating that the insulation performance of the material is significantly improved.

[0150] Dielectric loss tangent (Tanδ):

[0151] Example: 0.025;

[0152] Comparative ratio: 0.045;

[0153] Reduction: Through the method of the present invention, the dielectric loss tangent value is reduced by about 44.4%, indicating that the electrical loss of the material is significantly reduced.

[0154] By comparing the above experimental data with the comparative examples, it can be clearly seen that the preparation method of the biodegradable plastic modified liquid silica gel proposed by the present invention has significant advantages in electrical properties. Specifically, it is shown as follows:

[0155] Higher dielectric constant: Through fine-tuning steps, especially alternating electromagnetic field treatment, the dielectric constant of the material is significantly increased.

[0156] Lower conductivity: By precisely controlling the parameters of each step, the conductivity of the material is significantly reduced, enhancing its insulation properties.

[0157] Lower dielectric loss tangent: By optimizing the formulation and process parameters, the electrical loss of the material is significantly reduced and the overall performance is improved.

[0158] These results verify the effectiveness and superiority of the method of the present invention, making the final prepared material more suitable for application in fields such as high-performance electronic device packaging and sensor manufacturing.

[0159] Example 3

[0160] This embodiment proposes a preparation control system for biodegradable plastic modified liquid silica gel, such as Figure 2 As shown, including:

[0161] A premix preparation module is used to mix the biodegradable plastic and liquid silicone in a mass ratio of 1:3 and form a premix by ultrasonic treatment;

[0162] A carbon nanotube adding module, used for adding 4-5% of the carbon nanotubes to the premix, and stirring at 200-400 rpm for 14-16 minutes;

[0163] An organic silicon pre-crosslinking agent dropping module is used to drop 0.7-0.9 mol / L of organic silicon pre-crosslinking agent into the mixture under nitrogen protection, maintain the temperature at 50-70° C. for 20-40 minutes to obtain a reaction product;

[0164] A solidified product preparation module is used to apply an alternating electromagnetic field with a frequency of 40-60kHz and an intensity of 0.4-0.6T to the reaction product for 9-11 minutes, adjust the pH to 8-9, add 0.1-0.2wt% ammonium persulfate initiator, and cure at 60-80°C for 40-50 minutes to obtain a solidified product;

[0165] A test module, used for heat treating the solidified material at 70-90°C for 1-3 hours, and then cooling it to room temperature to obtain a sample, and testing the dielectric constant of the sample to be within the range of 12-13, and the conductivity to be at the level of 10^-5S / cm;

[0166] The optimization cycle module is used to repeat the preparation steps according to the test results until a material with a dielectric loss tangent value less than 0.03 is obtained.

[0167] In addition, the above modules are also used to implement other steps of the above-mentioned preparation control method of a biodegradable plastic modified liquid silicone when executed, which will not be described one by one here.

[0168] In summary, ultrasonic treatment and high-speed stirring are used to ensure the uniform distribution of carbon nanotubes in the matrix, and a series of fine-tuning steps such as the addition of silicone pre-crosslinking agent under nitrogen protection, alternating electromagnetic field treatment, pH adjustment, and initiator curing are used to effectively control and optimize the electrical properties of the material. This method not only solves the problem of difficult to accurately control electrical properties in the prior art, but also significantly improves the overall performance of the material, making it have a higher dielectric constant and lower conductivity while maintaining good mechanical properties. Ultimately, the materials prepared by this method can better meet the application fields with high requirements for electrical properties, such as high-performance electronic device packaging and sensor manufacturing.

[0169] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing biodegradable plastic modified liquid silica gel, characterized in that: The following steps are involved: S1: mixing the biodegradable plastic and liquid silicone in a mass ratio of 1:3, and subjecting the mixture to ultrasonic treatment to form a premix; S2: adding 4-5% of the total amount of carbon nanotubes to the premix, and stirring at 200-400 rpm for 14-16 minutes; S3: adding 0.7-0.9 mol / L of organosilicon pre-crosslinking agent dropwise to the mixture under nitrogen protection, maintaining the temperature at 50-70° C. for reaction for 20-40 minutes to obtain a reaction product; S4: applying an alternating electromagnetic field with a frequency of 40-60 kHz and an intensity of 0.4-0.6 T to the reaction product for 9-11 minutes, adjusting the pH to 8-9, adding 0.1-0.2 wt % of ammonium persulfate initiator, and curing at 60-80° C. for 40-50 minutes to obtain a cured product; S5: heat treating the solidified material at 70-90° C. for 1-3 hours, and then cooling it to room temperature to obtain a sample. The dielectric constant of the sample is tested to be in the range of 12-13, and the conductivity is at the level of 10^-5S / cm; S6: Repeat steps S2-S5 according to the test results until a material with a dielectric loss tangent value less than 0.03 is obtained.

2. The method for preparing a biodegradable plastic modified liquid silica gel according to claim 1, characterized in that: The method comprises mixing the degradable plastic and the liquid silica gel in a mass ratio of 1:3 and subjecting the mixture to ultrasonic treatment to form a premix, comprising: Weigh the degradable plastic and liquid silicone to make a mass ratio of 1:3, and record the masses m1 and m2, where m1 is the mass of the degradable plastic and m2 is the mass of the liquid silicone; Place the degradable plastic in a clean container, add the liquid silica gel, and ensure that the mass of the mixture satisfies the formula M=m1+m2, where M is the total mass of the mixture; Using a high-speed stirrer to preliminarily mix the mixture at a speed of 400-600 rpm for 4-6 minutes to form a preliminary mixture; The preliminary mixture is transferred to an ultrasonic processor, and the ultrasonic power is set to 70-90 W, the frequency is set to 30-50 kHz, and the processing time is set to 10-20 minutes to finally form a premix.

3. The method for preparing a biodegradable plastic modified liquid silica gel according to claim 2, characterized in that: The step of adding 4-5% of the total carbon nanotubes to the premix and stirring at 200-400 rpm for 14-16 minutes comprises: According to the total mass M of the preliminary mixture, the mass Mc of the carbon nanotubes to be added is calculated, and the mass Mc of the carbon nanotubes is 4-5% of the total mass M; Weighing carbon nanotubes with a mass of Mc, and slowly and evenly adding them to the preliminary mixture to form a mixed system containing carbon nanotubes; Placing the mixed system containing carbon nanotubes in a high-speed stirrer, setting the speed to 200-400 rpm, starting the stirrer and continuing to run; During the stirring process, the stirrer was paused every 5 minutes, and the mixing system was manually stirred with a spatula to ensure that the carbon nanotubes would not be deposited until the stirring cycle of 14-16 minutes was completed.

4. The method for preparing a biodegradable plastic modified liquid silica gel according to claim 3, characterized in that: The step of adding 0.7-0.9 mol / L of organosilicon pre-crosslinking agent to the mixture under nitrogen protection, maintaining the temperature at 50-70° C. for reaction for 20-40 minutes, and obtaining a reaction product, including: According to the total volume of the mixed system V = M + Mc, calculate the required volume of 0.7-0.9 mol / L organosilicon pre-crosslinking agent to ensure that it accounts for 10% of the total volume of the mixed system, that is, Vp = 0.1*V, where Vp is the volume of the pre-crosslinking agent; The mixed system is transferred to a reactor equipped with a nitrogen protection device, and the nitrogen flow is turned on to place the mixed system under a nitrogen protection environment; Under the condition of keeping the nitrogen flow rate constant, using a microinjection pump to dropwise add a volume of Vp of the organosilicon pre-crosslinking agent into the mixed system at a rate of Vp / 30 per minute; After the dropwise addition is completed, the temperature of the reactor is adjusted to 50-70° C. and maintained, and a timer is started to record the reaction time to ensure that the reaction lasts for 20-40 minutes to obtain the reaction product.

5. The method for preparing a biodegradable plastic modified liquid silica gel according to claim 4, characterized in that: The step of applying an alternating electromagnetic field having a frequency of 40-60 kHz and an intensity of 0.4-0.6 T to the reaction product for 9-11 minutes comprises: Transferring the reaction product into a non-magnetic container, and placing the non-magnetic container in a working area of ​​an alternating electromagnetic field device; Setting the parameters of the alternating electromagnetic field device so that its output frequency is 40-60kHz and the intensity is 0.4-0.6T; The alternating electromagnetic field device is started to apply an alternating electromagnetic field with a frequency of 40-60 kHz and an intensity of 0.4-0.6 T to the reaction product, and a timer is used to record the time to ensure that the treatment lasts for 9-11 minutes.

6. The method for preparing a biodegradable plastic modified liquid silica gel according to claim 5, characterized in that: The pH is adjusted to 8-9, 0.1-0.2 wt% of ammonium persulfate initiator is added, and the mixture is cured at 60-80° C. for 40-50 minutes to obtain a cured product, including: The mass Ma of the required pH adjuster is determined using the formula Ma=V*Ca*10^-3, where Ca is the concentration of the pH adjuster; Transferring the reaction product to a container with a stirring device, slowly adding a calculated amount of a pH adjuster, and continuously stirring until the pH value of the reaction product reaches 8-9; After the pH value of the reaction product stabilizes at 8-9, weigh 0.1-0.2 wt% of the total mass of the reaction product as ammonium persulfate initiator, sprinkle it evenly into the reaction product, and continue stirring for 4-6 minutes; Then the mixture is moved to a curing oven preheated to 60-80° C., and a curing treatment is performed for 40-50 minutes while maintaining a constant temperature to obtain the cured product.

7. The method for preparing a biodegradable plastic modified liquid silica gel according to claim 6, characterized in that: The solidified material is subjected to heat treatment at 70-90° C. for 1-3 hours, and then rapidly cooled to room temperature to obtain a sample, comprising: The solidified product is taken out of the curing oven and quickly transferred to a heat treatment device with a preset temperature of 70-90°C; The cured product is subjected to a heat treatment at 70-90° C. in the heat treatment equipment for a duration of 1-3 hours; After the heat treatment is completed, the solidified material is immediately taken out from the heat treatment equipment and quickly placed in a cooling device, and the solidified material is rapidly cooled to room temperature by quenching. The cooling rate Vc can be calculated according to the formula Vc=(Ti-Tf) / Tc, where Ti is the initial temperature, Tf is the final temperature room temperature, and Tc is the cooling time; After the solidified material is completely cooled to room temperature, a sample is obtained.

8. The method for preparing a biodegradable plastic modified liquid silica gel according to claim 7, characterized in that: The test of the sample dielectric constant to a range of 12-13, the conductivity to a level of 10^-5S / cm, includes: The sample is cut into a standard test size to ensure that its thickness D and area A meet the requirements of the test equipment, and the capacitance value C is calculated using the formula C=ε*A / D, where ε is the target dielectric constant 12-13; Install the sample in a test fixture of a dielectric constant tester and connect the measuring circuit; Start the dielectric constant tester, apply a specified voltage to the sample, and record the measured capacitance value C; After completing the dielectric constant test, the sample is transferred to a conductivity tester to start the test, and the conductivity value σ of the sample is recorded to ensure that it is at the level of 10^-5S / cm.

9. The method for preparing a biodegradable plastic modified liquid silica gel according to claim 8, characterized in that: Repeating steps S2-S5 according to the test results until a material having a dielectric loss tangent value less than 0.03 is obtained comprises: According to the test results of the sample, the dielectric loss tangent value Tanδ is recorded. If Tanδ is greater than 0.03, the formula or process parameters need to be adjusted; Calculate the new amount of carbon nanotubes added Mc' using the formula Mc' = Mc*(1+Δ%), where Δ% is the adjustment ratio; Use a new amount of carbon nanotubes Mc' to re-prepare the mixed system, and ensure that the mass of the mixed system satisfies the formula M'=m1+m2+Mc', where M' is the total mass of the new mixed system; The new mixed system is sequentially subjected to crosslinking agent addition, electromagnetic field treatment, pH adjustment, initiator addition, curing and heat treatment operations to obtain a new sample; Test the new sample and record the new dielectric constant, conductivity and dielectric loss tangent value Tanδ'; Compare the dielectric loss tangent value Tanδ' of the new sample with the target value 0.

03. If the requirement is still not met, adjust the amount of carbon nanotubes added again and repeat the test until the dielectric loss tangent value is less than 0.

03.

10. A control system for preparing biodegradable plastic modified liquid silica gel for implementing the preparation method according to any one of claims 1 to 9, characterized in that: include: A premix preparation module is used to mix the biodegradable plastic and liquid silicone in a mass ratio of 1:3 and form a premix by ultrasonic treatment; A carbon nanotube adding module, used for adding 4-5% of the carbon nanotubes to the premix, and stirring at 200-400 rpm for 14-16 minutes; An organic silicon pre-crosslinking agent dropping module is used to drop 0.7-0.9 mol / L organic silicon pre-crosslinking agent into the mixture under nitrogen protection, maintain the temperature at 50-70° C. for 20-40 minutes to obtain a reaction product; A solidified product preparation module is used to apply an alternating electromagnetic field with a frequency of 40-60kHz and an intensity of 0.4-0.6T to the reaction product for 9-11 minutes, adjust the pH to 8-9, add 0.1-0.2wt% ammonium persulfate initiator, and cure at 60-80°C for 40-50 minutes to obtain a solidified product; A test module, used for heat treating the solidified material at 70-90°C for 1-3 hours, and then cooling it to room temperature to obtain a sample, and testing the dielectric constant of the sample to be within the range of 12-13, and the conductivity to be at the level of 10^-5S / cm; The optimization cycle module is used to repeat the preparation steps according to the test results until a material with a dielectric loss tangent value less than 0.03 is obtained.

Images