A method for manufacturing nano-hollow silica particles by ammonium salt double templating

Abstract

The application relates to the technical field of hollow silica particle manufacturing, and discloses a method for manufacturing nano hollow silica particles by ammonium salt double-templating, which comprises the following steps: S1, selecting raw materials; S2, mixing the raw materials; S3, stirring; S4, adding a solution; S5, standing; and S6, obtaining. A solution is obtained by dissolving ammonium salt and a surfactant in deionized water, then the A solution is added to a B solution, the B solution is stirred, the A solution is mixed into the B solution, the mixing time of the B solution into the A solution is 1-5 min, then D solution and C solution are sequentially added, hollow silica particles are obtained after 6-8 hours of reaction, the core is composed of ammonium salt and a surfactant, the oligomers of silicon hydrolyzed from a silane coupling agent grow into a silica shell on the core, so that the hollow silica particles are obtained, the particle size distribution of the hollow silica particles is uniform, and the dispersibility of the hollow silica particles in resin is excellent.

Description

Technical Field

[0001] This invention relates to the field of hollow silica particle manufacturing technology, specifically to a method for manufacturing nano-hollow silica particles using ammonium salt dual-template synthesis. Background Technology

[0002] Currently, hollow silica is mainly synthesized and manufactured using methods such as soft template method, hard template method, and sol-gel method.

[0003] In both soft-templating and hard-templating methods for preparing hollow silica particles, template removal is difficult and can produce toxic substances. Furthermore, the soft-templating method produces hollow silica particles with uneven size. The hard-templating method, on the other hand, results in a high breakage rate for the hollow silica particles. The sol-gel method, however, easily introduces sodium, which can cause the hollow silica to melt.

[0004] In recent years, the demands for miniaturization, high-speed signals, and high-density wiring in electronic devices have placed increasingly higher requirements on printed circuit boards. Therefore, the preparation of hollow silica particles with excellent dispersibility in resin is crucial. Previous silica particles may have agglomerated due to uneven particle size during synthesis, leading to problems such as the generation of toxic substances during subsequent processing and difficulties in industrial production. To address these issues, a method for synthesizing nano-hollow silica particles using ammonium salt dual-templates is proposed. Summary of the Invention

[0005] The purpose of this invention is to provide a method for manufacturing nano-hollow silica particles by synthesizing ammonium salt dual templates, so as to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a method for manufacturing nano-hollow silica particles using ammonium salt dual-template synthesis, comprising the following steps:

[0007] S1. Selecting raw materials;

[0008] S2, Raw material mixing;

[0009] S3. Stir;

[0010] S4. Add solution;

[0011] S5. Let stand;

[0012] S6, Get.

[0013] Preferably, in S1, the selected raw materials are solution A and solution B, where solution A is a solution containing ammonium salt and surfactant, and solution B is anhydrous ethanol.

[0014] Preferably, in step S2, the raw material mixing involves first adding liquid B to the reactor while simultaneously stirring liquid B, and then mixing liquid A into liquid B.

[0015] Preferably, in step S3, the stirring time for liquid A and liquid B is 5 to 10 minutes.

[0016] Preferably, in step S4, the added solutions are solution C and solution D. Solution D is added to the mixed solution of A and B, and then solution C is added immediately.

[0017] Solution C is an alkaline compound solution, and solution D is tetraethyl orthosilicate.

[0018] Preferably, in step S5, the mixed solution is left to stand for 6-8 hours before hollow silica particles are obtained.

[0019] Preferably, the mixing time of liquid B to liquid A is 1 to 5 minutes, the addition time of liquid C to the reaction solution is 2 to 5 minutes, and the addition time of liquid D is 2 to 5 minutes.

[0020] Preferably, in the above-mentioned solution A, the solvent is deionized water;

[0021] The ammonium salt in solution A is selected from one of ammonium citrate, ammonium oxalate, and ammonium tartrate.

[0022] The surfactant is selected from one of tetrapropylammonium bromide, dodecyltrimethylammonium bromide, tetradecyltrimethylammonium bromide, hexadecyltrimethylammonium bromide, octadecyltrimethylammonium bromide, polyethylene glycol, ethylenediaminetetraacetic acid, and poloxamer.

[0023] Preferably, the above-mentioned liquid C can be selected from either 28% ammonia or 90% triethanolamine;

[0024] The reaction temperatures of solutions A, B, C, and D are below 40°C.

[0025] Preferably, the hollow silica particles described above have a pore volume of 0.1 cm³. 3 / g or less, the surface of the hollow silica particles was treated with a silane coupling agent;

[0026] The silicon dioxide shell has a space inside the shell;

[0027] The volume of the space portion accounts for 55% to 78% of the total volume of the silica sphere, the relative permittivity at 1 GHz is 1.1 to 3.0, and the dielectric loss tangent at 1 GHz is 0.0001 to 0.01.

[0028] The BET specific surface area of ​​the hollow silica particles is between 1 and 100 m². 2 / g;

[0029] The median particle size of the hollow silica particles is 0.5–10 μm;

[0030] The sphericity of the hollow silica particles is 0.86 to 1.0.

[0031] Compared with the prior art, the present invention, employing the above technical solution, has the following technical effects:

[0032] This invention relates to a solution A obtained by dissolving ammonium salts and surfactants in deionized water. Solution A is then added to solution B while stirring, and the mixture of solution A and solution B is stirred. The mixing time of solution B with solution A is 1–5 minutes. Next, solutions D and C are added sequentially. After reacting for 6–8 hours, hollow silica particles are obtained. The hollow silica particles are obtained by using ammonium salts and surfactants to form a core, while silicon oligomers hydrolyzed from a silane coupling agent grow onto the core as a silica shell. This invention provides a modified sol-gel method for manufacturing hollow silica particles with uniform particle size distribution and high hollowness. The hollow silica particles exhibit uniform particle size distribution, excellent dispersibility in resin, and are environmentally friendly and suitable for large-scale industrial production. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1 This is a SEM image of the hollow silica particles of the present invention;

[0035] Figure 2 This is a TEM image of the first hollow silica particle of the present invention;

[0036] Figure 3 This is a schematic diagram of the particle size distribution of the hollow silica particles of the present invention;

[0037] Figure 4 This is a TEM image of the second hollow silica particles of the present invention. Detailed Implementation

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] It should be noted that the structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which this application can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size should still fall within the scope of the technical content disclosed in this application, provided that they do not affect the effects and purposes that this application can produce.

[0040] Example 1

[0041] Please see Figures 1-4 This invention provides a technical solution: a method for manufacturing nano-hollow silica particles using ammonium salt dual-template synthesis, comprising the following steps:

[0042] S1. Select raw materials; the raw materials are selected as solution A and solution B. Solution A is a solution containing ammonium salt and surfactant, and solution B is anhydrous ethanol. There is no limit to the concentration of surfactant, preferably 0.01-0.2 mol / L, and particularly preferably 0.003-0.01 mol / L.

[0043] S2. Raw material mixing: The raw material mixing process involves first adding liquid B to the reactor while stirring liquid B, and then mixing liquid A into liquid B. The mixing time for adding liquid B to liquid A is 1 to 5 minutes, and the mixing time from the beginning to the end of mixing liquid B to liquid A is 1 to 5 minutes, preferably 3 minutes, and particularly preferably 2 minutes. After all liquid A has been added to liquid B, the stirring time is 5 to 10 minutes, preferably 7 minutes, and particularly preferably 5 minutes.

[0044] S3. Stirring; The stirring time for solutions A and B is 5 to 10 minutes; Solution A is deionized water as the solvent; The stirring speed is 100 to 300 rpm, preferably 150 to 300 rpm, and particularly preferably 200 to 250 rpm;

[0045] The ammonium salt in solution A is selected from one of ammonium citrate, ammonium oxalate, and ammonium tartrate, with ammonium citrate being particularly preferred. There is no limitation on the concentration of the ammonium salt, but it is preferred to be 0.01–0.2 mol / L, and particularly preferred to be 0.01–0.05 mol / L.

[0046] The surfactant is selected from one of tetrapropylammonium bromide, dodecyltrimethylammonium bromide, tetradecyltrimethylammonium bromide, hexadecyltrimethylammonium bromide, octadecyltrimethylammonium bromide, polyethylene glycol (molecular weight 300, 5000, 7000, 10000), ethylenediaminetetraacetic acid and poloxamer (F127), preferably hexadecyltrimethylammonium bromide and poloxamer (F127), and particularly preferably hexadecyltrimethylammonium bromide;

[0047] S4. Add solutions; the added solutions are solutions C and D. Add solution D to the mixed solution of A and B, and then immediately add solution C; solution C is an alkaline compound solution, and solution D is tetraethyl orthosilicate; solution C is added to the reaction solution over a time of 2–5 minutes. Solution D is added over a time of 2–5 minutes. Solution C can be selected from either 28% ammonia or 90% triethanolamine. Solution C is added to the reaction solution over a time of 2–5 minutes, preferably 3 minutes, and particularly preferably 2 minutes; solution D is added over a time of 2–5 minutes, preferably 3 minutes, and particularly preferably 2 minutes. For hollow silica particles, solution C preferably contains 28% ammonia or 90% triethanolamine, and particularly preferably 28% ammonia.

[0048] The reaction temperature of solutions A, B, C, and D is below 40°C. After adding solution C to the reaction mixture, stirring is immediately stopped, and the reaction mixture is aged at a specified temperature for a certain period of time. The aging temperature is preferably below 40°C, and particularly preferably 20–35°C.

[0049] S5. Settling; the mixed solution should be allowed to stand for 6–8 hours; the aging time is preferably 6–8 hours, particularly preferably 7 hours; after the aging reaction is complete, solid-liquid separation is required. Any general separation method (filtration, vacuum filtration, centrifugation, etc.) can be used to separate the reaction solution. Subsequently, a multi-step alcohol washing process is required; there are no restrictions on the alcohol washing method, but two steps are preferred. After the alcohol washing is completed, the solid should still be washed with water; there are no restrictions on the water washing method, but two steps are preferred.

[0050] S6. Obtain hollow silica particles; the shell of the hollow silica particles, the shell "containing silica" means containing more than 50% by mass of silica (SiO2). 2 The composition of the shell can be determined by ICP emission spectroscopy, flame atomic absorption spectroscopy, etc. The shell contains preferably more than 80% by mass of silica, more preferably more than 95% by mass, and theoretically up to 100% by mass. The shell contains preferably less than 100% by mass of silica, more preferably less than 99.99% by mass. The remaining portion can include alkali metal oxides and silicates, alkaline earth metal oxides and silicates, carbon, etc.

[0051] The pore volume of hollow silica particles is 0.1 cm.3 For particles with a density of less than / g, the surface of hollow silica particles was treated with a silane coupling agent.

[0052] The shell of silicon dioxide has a space inside the aforementioned shell; "having a space inside the shell" means that a hollow particle has a large space and a shell surrounding it.

[0053] The volume of the space portion accounts for 55% to 78% of the total volume of the silica sphere. The relative permittivity at 1 GHz is 1.1 to 3.0, and the dielectric loss tangent at 1 GHz is 0.0001 to 0.01. For the relative permittivity at 1 GHz, the lower limit is preferably 1.2 or higher, and particularly preferably 1.3 or higher. The upper limit is preferably 2.5 or lower, and particularly preferably 2.0 or lower. For the dielectric loss tangent at 1 GHz, the lower limit is preferably 0.0003 or higher, and particularly preferably 0.0005. The upper limit is preferably 0.01, and particularly preferably 0.001. The dielectric constant and dielectric loss tangent can be measured using a dedicated device via a perturbation-based resonator method.

[0054] The BET specific surface area of ​​hollow silica particles is 1–100 m². 2 / g; preferably 1-80m 2 / g, further preferred at 1-75m 2 / g, preferably 1-50m 2 / g; The BET surface area was determined using a specific surface area measuring device. As a pretreatment, the hollow silica particles were dried at 230°C for 50 mTorr, and the surface area was determined by a multi-point method using liquid nitrogen.

[0055] The median particle size of hollow silica particles is between 0.5 and 10 μm. If the median particle size is too small, the viscosity of the resin composition may increase or it may be difficult to disperse. Therefore, the lower limit is preferably 1 μm, and particularly preferably 1.2 μm. Furthermore, if the median particle size is too large, particles will be generated during the film formation of the resin composition. Therefore, the upper limit of the median particle size is preferably 5 μm, and particularly preferably 3 μm.

[0056] The sphericity of hollow silica particles is 0.86 to 1.0. If the sphericity is low, the hollow silica particles are easily broken, resulting in a larger specific surface area and a decrease in dielectric loss tangent. In the photographic projection image obtained by taking pictures using a scanning electron microscope (SEM), the maximum diameter (DL) and the minor diameter (DS) orthogonal to it of any 100 particles are measured. The average value of the ratio of the minimum diameter (DS) to the maximum diameter (DL) (DS / DL) can be used to represent the sphericity. From the perspective of light scattering and tactile feel, the sphericity is preferably 0.88 or higher, more preferably 0.89 or higher, and particularly preferably 0.91 or higher.

[0057] Hollow silica particles have a shell containing silica, with a hollow portion inside the shell. This hollow portion can be confirmed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). In SEM observation, observing partially open, broken particles confirms the hollow structure. Treating the surface of hollow silica particles with a silane coupling agent reduces the amount of residual silanol groups on the surface, hydrophobizes the surface, inhibits moisture adsorption, improves dielectric loss, and enhances affinity with resins when formulated into resin compositions, resulting in improved dispersibility and strength of the resin film.

[0058] Examples of silane coupling agents include aminosilane coupling agents, epoxysilane coupling agents, mercaptosilane coupling agents, silane coupling agents, and organosilazane compounds. Silane coupling agents can be used alone or in combination of two or more.

[0059] The preferred sintering temperature is 700–900℃, particularly 900℃. The preferred sintering time is 6–9 hours, particularly 7 hours. Surface treatment conditions are not limited and can be performed under normal conditions. Both dry and wet treatment methods can be used. From the perspective of uniform treatment, wet treatment is particularly preferred. Hollow silica particles can be used as various filler materials, and are particularly suitable as filler materials for resin compositions used in the fabrication of electronic substrates for electronic devices such as computers, laptops, digital cameras, smartphones, and communication devices such as game consoles. Furthermore, it is environmentally friendly and suitable for large-scale industrial production.

[0060] Dissolve 5g of ammonium citrate and 1.6g of hexadecyltrimethylammonium bromide in 15g of deionized water to obtain solution A with an ammonium salt concentration of 0.02mol / L and a hexadecyltrimethylammonium bromide concentration of 0.004mol / L; measure 1000ml of anhydrous ethanol using a graduated cylinder to obtain solution B; measure 40ml of tetraethyl orthosilicate using a graduated cylinder to obtain solution D; and measure 80ml of 28% ammonia solution using a graduated cylinder to obtain solution C.

[0061] While maintaining constant stirring at 200 rpm, first add 1000 ml of solution B to the reactor. Then, over 2 minutes, add 15 ml of solution A to solution B at a uniform rate. After the addition of solution A is complete, continue stirring for 5 minutes. Next, similarly, add 40 ml of solution D to the reactor at a uniform rate over 2 minutes. After the addition of solution D is complete, immediately add 80 ml of solution C to the reactor, and solution C must be added uniformly over 2 minutes. After the addition of solution C is complete, immediately stop stirring and allow the reaction to stand for 7 hours.

[0062] The obtained reaction solution was subjected to solid-liquid separation, followed by two alcohol washes and two water washes. After drying, it was sintered at 900℃ for 7 hours to obtain hollow silica particles.

[0063] Figure 1 , Figure 2 and Figure 3 The images shown are SEM images, TEM images, and particle size distribution results of the hollow silica particles in this embodiment.

[0064] Example 2

[0065] The difference between this embodiment and Embodiment 1 is that:

[0066] Dissolve 4g of ammonium citrate and 1.6g of hexadecyltrimethylammonium bromide in 15g of deionized water to obtain solution A with an ammonium salt concentration of 0.016mol / L and a hexadecyltrimethylammonium bromide concentration of 0.004mol / L; measure 1000ml of anhydrous ethanol using a graduated cylinder to obtain solution B; measure 40ml of tetraethyl orthosilicate using a graduated cylinder to obtain solution D; and measure 80ml of 28% ammonia solution using a graduated cylinder to obtain solution C.

[0067] While maintaining continuous stirring at 200 rpm, first add 1000 ml of solution B to the reactor. Then, over 2 minutes, add 15 ml of solution A to solution B at a uniform rate. After the addition of solution A is complete, continue stirring for 5 minutes. Next, similarly, add 40 ml of solution D to the reactor at a uniform rate over 2 minutes. After the addition of solution D is complete, immediately add 80 ml of solution C to the reactor, and add solution C at a uniform rate over 2 minutes. After the addition of solution C is complete, immediately stop stirring and allow the reaction to stand for 7 hours.

[0068] The obtained reaction solution was subjected to solid-liquid separation, followed by two alcohol washes and two water washes. After drying, it was sintered at 900℃ for 7 hours to obtain hollow silica particles.

[0069] Example 3

[0070] The difference between this embodiment and Embodiments 1 and 2 is that:

[0071] Dissolve 5g of ammonium citrate and 1.0g of hexadecyltrimethylammonium bromide in 15g of deionized water to obtain solution A with an ammonium salt concentration of 0.02mol / L and a hexadecyltrimethylammonium bromide concentration of 0.0025mol / L; measure 1000ml of anhydrous ethanol using a graduated cylinder to obtain solution B; measure 40ml of tetraethyl orthosilicate using a graduated cylinder to obtain solution D; and measure 80ml of 28% ammonia solution using a graduated cylinder to obtain solution C.

[0072] While maintaining continuous stirring at 200 rpm, first add 1000 ml of solution B to the reactor. Then, over 2 minutes, add 15 ml of solution A to solution B at a uniform rate. After the addition of solution A is complete, continue stirring for 5 minutes. Next, similarly, add 40 ml of solution D to the reactor at a uniform rate over 2 minutes. After the addition of solution D is complete, immediately add 80 ml of solution C to the reactor, and add solution C at a uniform rate over 2 minutes. After the addition of solution C is complete, immediately stop stirring and allow the reaction to stand for 7 hours.

[0073] The obtained reaction solution was subjected to solid-liquid separation, followed by two alcohol washes and two water washes. After drying, it was sintered at 900℃ for 7 hours to obtain hollow silica particles.

[0074] Comparative Example 1

[0075] Dissolve 5g of ammonium citrate and 1.6g of hexadecyltrimethylammonium bromide in 15g of deionized water to obtain solution A with an ammonium salt concentration of 0.02mol / L and a hexadecyltrimethylammonium bromide concentration of 0.004mol / L; measure 1000ml of anhydrous ethanol using a graduated cylinder to obtain solution B; measure 20ml of tetraethyl orthosilicate using a graduated cylinder to obtain solution D; and measure 80ml of 28% ammonia solution using a graduated cylinder to obtain solution C.

[0076] While maintaining continuous stirring at 200 rpm, first add 1000 ml of solution B to the reactor. Then, over 2 minutes, add 15 ml of solution A to solution B at a uniform rate. After the addition of solution A is complete, continue stirring for 5 minutes. Next, similarly, add 20 ml of solution D to the reactor at a uniform rate over 2 minutes. After the addition of solution D is complete, immediately add 80 ml of solution C to the reactor, and add solution C at a uniform rate over 2 minutes. After the addition of solution C is complete, immediately stop stirring and allow the reaction to stand for 7 hours.

[0077] The obtained reaction solution was subjected to solid-liquid separation, followed by two alcohol washes and two water washes. After drying, it was sintered at 900℃ for 7 hours to obtain hollow silica particles.

[0078] Comparative Example 2

[0079] The difference between this comparative example and Comparative Example 1 is that:

[0080] Dissolve 5g of ammonium citrate and 1.6g of hexadecyltrimethylammonium bromide in 15g of deionized water to obtain solution A with an ammonium salt concentration of 0.02mol / L and a hexadecyltrimethylammonium bromide concentration of 0.004mol / L; measure 1000ml of anhydrous ethanol using a graduated cylinder to obtain solution B; measure 10ml of tetraethyl orthosilicate using a graduated cylinder to obtain solution D; and measure 80ml of 28% ammonia solution using a graduated cylinder to obtain solution C.

[0081] While maintaining continuous stirring at 200 rpm, first add 1000 ml of solution B to the reactor. Then, over 2 minutes, add 15 ml of solution A to solution B at a uniform rate. After the addition of solution A is complete, continue stirring for 5 minutes. Next, similarly, add 10 ml of solution D to the reactor at a uniform rate over 2 minutes. After the addition of solution D is complete, immediately add 80 ml of solution C to the reactor, and add solution C at a uniform rate over 2 minutes. After the addition of solution C is complete, immediately stop stirring and allow the reaction to stand for 7 hours.

[0082] The obtained reaction solution was subjected to solid-liquid separation, followed by two alcohol washes and two water washes. After drying, it was sintered at 900℃ for 7 hours to obtain hollow silica particles.

[0083] Comparative Example 3

[0084] This comparative example differs from Comparative Examples 1, 2, and 3 in that:

[0085] Dissolve 6g of ammonium citrate and 1.6g of hexadecyltrimethylammonium bromide in 15g of deionized water to obtain solution A with an ammonium salt concentration of 0.024mol / L and a hexadecyltrimethylammonium bromide concentration of 0.004mol / L; measure 1000ml of anhydrous ethanol using a graduated cylinder to obtain solution B; measure 40ml of tetraethyl orthosilicate using a graduated cylinder to obtain solution D; and measure 80ml of 28% ammonia solution using a graduated cylinder to obtain solution C.

[0086] While maintaining continuous stirring at 200 rpm, first add 1000 ml of solution B to the reactor. Then, over 2 minutes, add 15 ml of solution A to solution B at a uniform rate. After the addition of solution A is complete, continue stirring for 5 minutes. Next, similarly, add 40 ml of solution D to the reactor at a uniform rate over 2 minutes. After the addition of solution D is complete, immediately add 80 ml of solution C to the reactor, and add solution C at a uniform rate over 2 minutes. After the addition of solution C is complete, immediately stop stirring and allow the reaction to stand for 7 hours.

[0087] The obtained reaction solution was subjected to solid-liquid separation, followed by two alcohol washes and two water washes. After drying, it was sintered at 900℃ for 7 hours to obtain hollow silica particles.

[0088] Comparative Example 4

[0089] This comparative example differs from Comparative Examples 1, 2, 3, and 4 in that:

[0090] Dissolve 5g of ammonium citrate and 2.5g of hexadecyltrimethylammonium bromide in 15g of deionized water to obtain solution A with an ammonium salt concentration of 0.02mol / L and a hexadecyltrimethylammonium bromide concentration of 0.00625mol / L; measure 1000ml of anhydrous ethanol using a graduated cylinder to obtain solution B; measure 40ml of tetraethyl orthosilicate using a graduated cylinder to obtain solution D; and measure 80ml of 28% ammonia solution using a graduated cylinder to obtain solution C.

[0091] While maintaining continuous stirring at 200 rpm, first add 1000 ml of solution B to the reactor. Then, over 2 minutes, add 15 ml of solution A to solution B at a uniform rate. After the addition of solution A is complete, continue stirring for 5 minutes. Next, similarly, add 40 ml of solution D to the reactor at a uniform rate over 2 minutes. After the addition of solution D is complete, immediately add 80 ml of solution C to the reactor, and add solution C at a uniform rate over 2 minutes. After the addition of solution C is complete, immediately stop stirring and allow the reaction to stand for 7 hours.

[0092] The obtained reaction solution was subjected to solid-liquid separation, followed by two alcohol washes and two water washes. After drying, it was sintered at 900℃ for 7 hours to obtain hollow silica particles.

[0093] Examples 1, 2, 3, and 4, as well as Comparative Examples 1, 2, 3, and 4, were synthesized and sintered according to the above method, and the test data are summarized below:

[0094]

[0095] After sintering, silica particles with low dielectric constant, low dielectric loss tangent, and high hollowness can be obtained. Furthermore, after treatment with a silane coupling agent, the hollow silica particles exhibit excellent dispersibility in resin.

[0096] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. It should be noted that implementations not illustrated or described in the drawings or the main text of the specification are forms known to those skilled in the art and are not described in detail. Furthermore, the definitions of the components described above are not limited to the various specific structures, shapes, or methods mentioned in the embodiments, and those skilled in the art can easily modify or substitute them.

[0097] Those skilled in the art will understand that the features described in the various embodiments and / or claims of the present invention can be combined or combined in various ways, even if such combinations or combinations are not explicitly described in the present invention. In particular, the features described in the various embodiments and / or claims of the present invention can be combined or combined in various ways without departing from the spirit and teachings of the present invention. All such combinations and / or combinations fall within the scope of the present invention.

[0098] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for manufacturing ammonium salt double templated nano hollow silica particles, characterized by: Includes the following steps: S1. Selecting raw materials; S2, Raw material mixing; S3. Stir; S4. Add solution; S5. Let stand; S6, Obtain; In S1, the selected raw materials are solution A and solution B, where solution A is a solution containing ammonium salt and surfactant, and solution B is anhydrous ethanol. In S2, the raw material mixing involves first adding liquid B to the reactor while stirring liquid B, and then mixing liquid A into liquid B. In S3, the stirring time for liquid A and liquid B is 5 to 10 minutes; In S4, the added solutions are solution C and solution D. Solution D is added to the mixed solution of A and B, and then solution C is added immediately. Solution C is an alkaline compound solution, and solution D is tetraethyl orthosilicate; In S5, the mixed solution is left to stand for 6-8 hours, and then hollow silica particles are obtained. The mixing time for adding solution B to solution A is 1-5 minutes, the mixing time for adding solution C to the reaction solution is 2-5 minutes, and the mixing time for adding solution D is 2-5 minutes. The solvent for solution A is deionized water. The ammonium salt in solution A is selected from one of ammonium citrate, ammonium oxalate, and ammonium tartrate. The surfactant is selected from one of tetrapropylammonium bromide, dodecyltrimethylammonium bromide, tetradecyltrimethylammonium bromide, hexadecyltrimethylammonium bromide, octadecyltrimethylammonium bromide, polyethylene glycol, ethylenediaminetetraacetic acid, and poloxamer; The C solution can be selected from either 28% ammonia or 90% triethanolamine; The reaction temperatures of solutions A, B, C, and D are below 40°C.

2. The method according to claim 1, wherein the method is characterized by: The hollow silica particles have a pore volume of 0.1 cm 3 / g or less, and the surface of the hollow silica particles is surface-treated with a silane coupling agent. The silicon dioxide shell has a space inside the shell; The volume of the space portion accounts for 55% to 78% of the total volume of the silica sphere, the relative permittivity at 1 GHz is 1.1 to 3.0, and the dielectric loss tangent at 1 GHz is 0.0001 to 0.

01. The BET specific surface area of the hollow silica particles is in the range of 1 to 100 m 2 / g; The median particle size of the hollow silica particles is 0.5–10 μm; The sphericity of the hollow silica particles is 0.86 to 1.0.

Images