A spiked mesoporous silica nanosphere, its preparation method, and its application in reinforcing and toughening polymer materials.

Abstract

This invention belongs to the field of polymer material reinforcement and toughening, specifically relating to a spiked-mesoporous silica nanosphere, its preparation method, and its application in polymer material reinforcement and toughening. The basic steps for synthesizing this spiked-mesoporous silica nanosphere include: firstly, synthesizing low-crosslinked, smooth-surfaced mesoporous silica nanospheres through an oil-water two-phase reaction system; subsequently, inducing normal shrinkage of the pore walls through secondary deep crosslinking to form a rigid nanospike surface structure while maintaining the original mesoporous structure. This spiked-mesoporous silica nanosphere exhibits good monodispersity, high particle size uniformity (50-100 nm adjustable), centrally divergent mesopores with high pore size uniformity (6-8 nm adjustable), highly open pores on the sphere surface, and spike height adjustable from 3-5 nm. This material is suitable for reinforcing and toughening various elastomers, resins, and other polymer materials, effectively overcoming the "strength-toughness mutual exclusion" problem and synergistically enhancing existing mechanical property reinforcement systems.

Description

Technical Field

[0001] This invention belongs to the field of polymer material reinforcement and toughening, specifically relating to a spiked mesoporous silica nanosphere, its preparation method, and its application in polymer material reinforcement and toughening. Background Technology

[0002] When improving the mechanical properties of polymer materials using traditional additives or auxiliaries, a common dilemma arises: "strength and toughness are mutually exclusive," meaning that reinforcement and toughening are difficult to achieve simultaneously. The underlying physical principle is that the reinforcing effect relies on the interfacial stress transfer between rigid particles and flexible polymer chains, increasing modulus and strength by constraining molecular chain movement; while toughening depends on molecular chain slippage, orientation, and energy dissipation mechanisms to enhance fracture energy. Traditional reinforcing agents such as silica primarily rely on weak interactions like van der Waals forces or hydrogen bonds to achieve stress transfer, making them prone to interfacial slippage or debonding under external forces, thus hindering the synergistic achievement of high strength and high toughness.

[0003] To construct an efficient stress transfer and energy dissipation system, it is necessary to overcome the limitations of traditional interfacial interaction modes and establish a multi-level strengthening mechanism. First, surface chemical modification can enhance the primary interfacial bonding, enabling efficient stress transfer from flexible chains to rigid fillers. Second, porous structures can significantly expand the interfacial area, promoting uniform stress dispersion and avoiding localized stress concentration. Furthermore, surface micro / nano structures can be used to hook and entangle with polymer chains, elevating the stress transfer path from simple intermolecular interactions to a physical network level. Finally, covalent cross-linked networks achieve uniform force dispersion, and energy dissipation relies on the restricted slippage of molecular chains. Guided by this mechanism, filler designs combining porous structures and surface protrusions can synergistically leverage large specific surface area and mechanical interlocking effects, simultaneously improving the rigidity and toughness of the material without relying on strong chemical bonds.

[0004] Mesoporous nanoparticles, due to their interconnected channels, can provide anchoring space for polymer chains, and their huge specific surface area can promote dynamic interfacial bonding. If spike structures are further constructed on their surface, the ability to form topological entanglement with molecular chains will be significantly enhanced, providing an ideal platform for achieving high strength and high toughness.

[0005] However, to achieve this simultaneous enhancement and toughening mechanism, the key lies in the precise construction of micro- and nano-scale fine structures: their pore size needs to be much larger than the dynamic diameter of the polymer chain, usually greater than 6 nanometers, to ensure unobstructed channels and highly open pores, facilitating the penetration and entanglement of the polymer chain; the height of the surface spikes also needs to be significantly greater than the size of the polymer chain, not less than 3 nanometers, to ensure the formation of effective topological hooks and mechanical interlocks; at the same time, the nanoparticles themselves need to have excellent dispersibility to avoid stress concentration or optical fogging caused by agglomeration.

[0006] It is worth noting that existing synthesis strategies, such as core-shell growth and post-etching techniques, are insufficient to simultaneously meet the aforementioned multiple structural requirements. Core-shell growth typically involves first synthesizing solid or non-porous silica nanospheres as a "seed" core, then precisely controlling reaction kinetics to non-uniformly epitaxially grow spike structures on the outer layer of the mesoporous silica nanospheres. However, the spike growth process in this method easily clogs the pore openings of the porous core. Even if some spike morphology is obtained, the pore size is often limited to below 3 nanometers, making it suitable only for loading small organic molecules and unable to accommodate the entry and restricted movement of polymer chains. Post-etching techniques involve first preparing a complete precursor sphere with a specific structure, then selectively removing some material through chemical etching to "sculpt" the spike structure. However, this etching process often leads to uniform thinning of the pore walls, making it difficult to precisely control the morphology and height of the spikes and easily disrupting the integrity and order of the mesoporous structure, thus losing its core functions of stress transfer and dispersion.

[0007] Therefore, developing a novel synthesis method that can synergistically regulate the mesoporous structure, surface spike structure, and overall morphology and particle size of nanoparticles has become a key bottleneck in promoting the practical application of this high-performance nano-reinforcer. Summary of the Invention

[0008] The purpose of this invention is to address the problems existing in the prior art, such as the difficulty of constructing a large mesoporous structure with a divergent center and an open surface using existing core-shell growth methods and post-etching techniques, and the difficulty of precisely controlling the morphology of the spikes by constructing spikes, etc. A synthesis strategy is developed that utilizes cross-linking to induce uneven shrinkage to form a spike surface structure while retaining the porous structure, thereby achieving the synthesis of a mesoporous silica nanosphere with a spike surface (hereinafter referred to as spike-mesoporous silica nanosphere).

[0009] The synthesis steps of the spiked-mesoporous silica nanospheres include: synthesizing mesoporous silica nanospheres with a smooth surface and low cross-linking degree by coordinating interfacial micelle assembly, precursor assembly, and cross-linking reaction kinetics; after liquid-liquid separation and spray drying, non-uniform shrinkage is induced by a secondary deep cross-linking reaction to form a rigid nanospike surface structure while maintaining the original mesoporous structure. The micro / nanostructure characteristics of the spiked-mesoporous silica nanospheres are: highly monodisperse nanospheres with a particle size of 50-100 nm, centrally divergent mesopores with a pore size of 6-8 nm, highly open surface pores, and spike height of 3-5 nm. This characteristic micro / nanostructure of the spiked-mesoporous silica nanospheres can efficiently accommodate polymer chain penetration and achieve "mechanical interlocking and topological entanglement" with the polymer chains through surface spikes. Under stress, the molecular chains slide in multiple directions and reversibly along the nanoparticle interface under the constraint of interfacial topological entanglement, effectively consuming mechanical energy. Therefore, it can be applied in fields such as elastomer strengthening and resin strengthening.

[0010] The technical solution of the present invention is as follows:

[0011] In a first aspect, a method for preparing spiked mesoporous silica nanospheres includes the following steps:

[0012] Step 1: Add the template agent and the first catalyst to deionized water as the aqueous phase, and add the silicon source to the first solvent as the oil phase. The aqueous phase and the oil phase undergo a two-phase reaction under stirring. The product obtained from the reaction is separated and dried (preferably spray dried) to obtain mesoporous silica nanospheres.

[0013] Step 2: Disperse the mesoporous silica nanospheres in a second solvent, then add a second catalyst and a structure protectant. After that, adjust the pH to 8-11 using a buffer solution and react. The product obtained from the reaction is centrifuged, washed, and dried to obtain the spiked-mesoporous silica nanospheres.

[0014] In a further improvement, in step 1, the template agent is at least one of hexadecyltrimethylammonium bromide, hexadecyltrimethylammonium chloride, sodium dodecyl sulfate, sodium dodecyl sulfonate, and a poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) triblock copolymer; preferably, the template agent is a combination of hexadecyltrimethylammonium bromide and hexadecyltrimethylammonium chloride; more preferably, the HLB value of the mixture of hexadecyltrimethylammonium bromide and hexadecyltrimethylammonium chloride is 12.

[0015] The template agent has a mass fraction of 5% to 50% in the aqueous phase; preferably, the mass fraction of the template agent in the aqueous phase is 45%.

[0016] The first catalyst is at least one of hydroxyethyl ethylenediamine, 2-methylaminoethanol, aminopropanol, aminobutanetriol, serine, triethanolamine, isopropanolamine, phenylglycine, or valine; preferably, the first catalyst is a mixture of 2-methylaminoethanol and triethanolamine; more preferably, the pKa of the mixture is 8.5.

[0017] The mass fraction of the first catalyst in the aqueous phase is 0.1% to 20%. Preferably, the mass fraction of the first catalyst in the aqueous phase is 2%.

[0018] In a further improvement, in step 1, the silicon source is at least one of bis(triethoxysilyl)methane, 1,4-bis(triethoxysilyl)benzene, 1,2-bis(triethoxysilyl)ethane, tetramethyl orthosilicate, tetraethyl orthosilicate, tetrapropyl orthosilicate, or sodium silicate; preferably, the silicon source is a combination of tetraethyl orthosilicate and tetramethyl orthosilicate in a mass ratio of 5:2.

[0019] The silicon source has a mass fraction of 2-50% in the oil phase; preferably, the silicon source has a mass fraction of 10% in the oil phase.

[0020] The first solvent is at least one of n-hexane, cyclohexane, or toluene; preferably, the first solvent is a mixture of toluene and cyclohexane in a volume ratio of 1:1.

[0021] In a further improvement, the mass ratio of the oil phase to the water phase is (0.2~1):1; preferably, the mass ratio of the oil phase to the water phase is 0.25:1.

[0022] A further improvement is made in step 1, where the temperature of the biphasic reaction is 20~80℃; preferably, the temperature of the biphasic reaction is 80℃. The reaction time is 0.5~6 days; preferably, the reaction time is 3 days.

[0023] The stirring speed during the two-phase reaction is 100~800 rpm, preferably 400 rpm.

[0024] In a further improvement, in step 2, the second solvent is at least one of tetrahydrofuran, ethanol, deionized water, N,N-dimethylformamide, methanol, or isopropanol; preferably, the second solvent is a mixture of tetrahydrofuran and deionized water in a volume ratio of 1:1.

[0025] The second solvent and mesoporous silica nanospheres are fed at a mass ratio of (100~500):1; preferably, the second solvent and mesoporous silica nanospheres are fed at a mass ratio of 350:1.

[0026] The second catalyst is at least one of 1,4-diazabicyclo[2.2.2]octane, 1,8-diazabicyclo[5.4.0]undec-7-ene, 1,4-diazabicyclo[2.2.2]octane, 4-dimethylaminopyridine, tetramethylammonium hydroxide, N-methylmorpholine, triethylamine or triethanolamine; preferably, the second catalyst is 4-dimethylaminopyridine.

[0027] The mass ratio of the second catalyst to the mesoporous silica nanospheres is (0.5~5):1; preferably, the mass ratio of the second catalyst to the mesoporous silica nanospheres is 0.8:1.

[0028] The structural protective agent is at least one of polyvinylpyrrolidone, hexadecyltrimethylammonium bromide, polydiallyldimethylammonium chloride, sodium citrate, or polyacrylic acid; preferably, the structural protective agent is hexadecyltrimethylammonium bromide.

[0029] The mass ratio of the structural protective agent to the mesoporous silica nanospheres is (0.4~6):1; preferably, the mass ratio of the structural protective agent to the mesoporous silica nanospheres is 0.5:1.

[0030] The buffer solution is one of an ammonia-ammonium chloride buffer solution, a sodium carbonate-sodium bicarbonate buffer solution, or a glycine-sodium hydroxide buffer solution; preferably, the buffer solution is a sodium carbonate-sodium bicarbonate buffer solution. Preferably, the pH of the solution is adjusted to 10 before the reaction.

[0031] The reaction temperature in step 2 is 50~350℃, preferably 60℃ or 350℃. The reaction time is 0.5~7 days, preferably 3 days.

[0032] Secondly, a spiked mesoporous silica nanosphere is prepared using the above-mentioned preparation method.

[0033] In a further improvement, the spiked-mesoporous silica nanospheres have a particle size of 50~100nm, the mesoporous channels of the spiked-mesoporous silica nanospheres have a centrally divergent structure with a pore size of 6~8nm and an open surface, and the surface of the spiked-mesoporous silica nanospheres has a spike structure with a height of 3~5nm.

[0034] Thirdly, the application of the spiked-mesoporous silica nanospheres in the reinforcement and toughening of polymer materials. When added to polymer materials, the spiked-mesoporous silica nanospheres can strengthen and toughen the polymer materials.

[0035] In a further improvement, the polymer material is an elastomer or a resin.

[0036] The elastomers include, but are not limited to, addition-cure silicone rubber (Dow Corning 184 elastomer), polyurethane, styrene-butadiene rubber, etc.

[0037] The resins include, but are not limited to, PVB (polyvinyl butyral), polyethylene resin, polypropylene resin, epoxy resin, etc.

[0038] Compared with the prior art, the beneficial effects of this invention are as follows:

[0039] 1. Compared with other silica nanospheres, the spiked-mesoporous silica nanospheres prepared in this invention have large mesoporous channels with open surfaces radiating from the center (channel diameter can reach up to 8 nm), adjustable height (by adjusting the secondary crosslinking reaction temperature) and uniformly distributed surface spikes, and adjustable particle size (e.g., by adjusting the stirring speed), so that various parameters of the spiked-mesoporous silica nanospheres can be controlled, thereby controlling the mechanical properties of polymer materials with the spiked-mesoporous silica nanospheres added.

[0040] 2. Compared with other nano-reinforcing agents, the spiked-mesoporous silica nanospheres prepared in this invention can achieve a strong anchoring effect close to the strength of covalent bonds without relying on chemical covalent bonds. At the same time, it allows the entangled molecular chains to undergo multi-directional, restricted reversible slippage under force to improve energy dissipation efficiency. This makes it applicable to a variety of polymer materials (such as elastomers and resin materials, which are all general-purpose) and has broad application value.

[0041] 3. The preparation method of the present invention has the advantages of simple steps and low cost. The prepared spiked-mesoporous silica nanospheres have the advantages of good dispersibility, good uniformity, and customizable hydrophilicity and hydrophobicity (the silica nanospheres have multiple hydroxyl groups on their surface, which can be used as reaction sites for post-derivation, such as grafting molecular chains with different properties to achieve the purpose of customizing hydrophilicity and hydrophobicity). Attached Figure Description

[0042] Figure 1 This is a transmission electron microscope image of sample 1 synthesized in Example 1;

[0043] Figure 2 Here is a scanning electron microscope image of sample 1 synthesized in Example 1;

[0044] Figure 3 The image shown is a transmission electron microscope (TEM) image of sample 2 synthesized in Example 1.

[0045] Figure 4 Here is a scanning electron microscope image of sample 2 synthesized in Example 1;

[0046] Figure 5 The image shown is a transmission electron microscope (TEM) image of sample 3 synthesized in Example 2.

[0047] Figure 6 The image shown is a scanning electron microscope (SEM) image of sample 3 synthesized in Example 2.

[0048] Figure 7 An optical photograph of elastomer sample 4, which is comparative example 1;

[0049] Figure 8 This is an optical photograph of elastomer sample 1 from Example 1;

[0050] Figure 9 The tensile properties test diagram is for elastomer sample 4 of Comparative Example 1.

[0051] Figure 10 The image shows the cyclic tensile test results of elastomer sample 4 in Comparative Example 1.

[0052] Figure 11 The tensile properties test diagram is for elastomer sample 5 of Comparative Example 2.

[0053] Figure 12The tensile properties test diagram is for elastomer sample 6 of Comparative Example 3.

[0054] Figure 13 This is a tensile property test diagram of elastomer sample 1 from Example 1;

[0055] Figure 14 This is a cyclic tensile test diagram of elastomer sample 1 from Example 1;

[0056] Figure 15 This is a tensile property test diagram of elastomer sample 2 from Example 2;

[0057] Figure 16 An optical photograph of resin sample 7, which is comparative example 4;

[0058] Figure 17 An optical photograph of resin sample 3 from Example 3;

[0059] Figure 18 The tensile properties test diagram is for resin sample 7 of Comparative Example 4.

[0060] Figure 19 The tensile properties test diagram is for resin sample 8 of Comparative Example 5.

[0061] Figure 20 This is a tensile property test diagram of resin sample 3 in Example 3. Detailed Implementation

[0062] The present invention will now be described in further detail with reference to specific embodiments and accompanying drawings. Example 1

[0063] Step 1: The template agent and the first catalyst are added to deionized water and mixed to form the aqueous phase. The template agent is a combination of hexadecyltrimethylammonium bromide and hexadecyltrimethylammonium chloride. The HLB value of the mixture of hexadecyltrimethylammonium bromide and hexadecyltrimethylammonium chloride is 12, and the mass fraction of the template agent in the aqueous phase is 45%. The first catalyst is a mixture of 2-methylaminoethanol and triethanolamine. The pKa of the mixture is 8.5, and the mass fraction of the first catalyst in the aqueous phase is 2%.

[0064] A silicon source is added to a first solvent as an oil phase. The silicon source is a combination of tetraethyl orthosilicate and tetramethyl orthosilicate in a mass ratio of 5:2. The first solvent is a mixture of toluene and cyclohexane in a volume ratio of 1:1. The mass fraction of the silicon source in the oil phase is 10%.

[0065] The oil phase and water phase were mixed at a mass ratio of 0.25:1. The mixture was magnetically stirred at 400 rpm to induce a two-phase reaction. The reaction was carried out at 80°C for 3 days. After the reaction, the resulting product was separated and spray-dried to obtain mesoporous silica nanospheres with low cross-linking degree, smooth surface, and open, centrally divergent surfaces (referred to as Sample 1). The transmission electron microscope image of Sample 1 is shown below. Figure 1 The scanning electron microscope image of sample 1 is shown below. Figure 2 .

[0066] Step 2: Add the mesoporous silica nanospheres obtained in Step 1 and the second solvent to a hydrothermal reactor. Stir to disperse the mesoporous silica nanospheres in the second solvent. The second solvent is a mixture of tetrahydrofuran and deionized water at a volume ratio of 1:1. The mass ratio of the second solvent to the mesoporous silica nanospheres is 350:1. Then, add the second catalyst, the structure protectant, and the buffer solution to the hydrothermal reactor. The second catalyst is 4-dimethylaminopyridine, the structure protectant is hexadecyltrimethylammonium bromide, and the buffer solution is a sodium carbonate-sodium bicarbonate buffer solution. The mass ratio of the second catalyst to the mesoporous silica nanospheres is 0.8:1, and the mass ratio of the structure protectant to the mesoporous silica nanospheres is 0.5:1. After adjusting the pH of the solution in the hydrothermal reactor to 10.0 using the sodium carbonate-sodium bicarbonate buffer solution, react in the hydrothermal reactor at 60°C for 3 days. After the reaction, the product is centrifuged, washed, and spray-dried to obtain sample 2. Sample 2 is a spiked-mesoporous silica nanosphere with open mesoporous channels radiating from the center and rigid nanospikes uniformly distributed on the outer surface. A transmission electron microscope image of Sample 2 is shown below. Figure 3 The scanning electron microscope image of sample 2 is shown below. Figure 4 .

[0067] Sample 2 was added to commercially available Dow Corning 184 elastomer (component A and component B were added in a mass ratio of 10:1) to obtain elastomer sample 1. Tensile and cyclic tensile tests were performed on elastomer sample 1, and the results are shown below. Figure 13 and Figure 14 In this example, the addition percentage of Sample 2 is 2.5%, which is the mass of Sample 2 / the mass of commercially available Dow Corning 184 elastomer. Example 2

[0068] The mesoporous silica nanospheres obtained in Example 1 (Sample 1) and the second solvent were added to a hydrothermal reactor. The mixture was stirred to disperse the mesoporous silica nanospheres in the second solvent, which was a mixture of tetrahydrofuran and deionized water in a volume ratio of 1:1. The mass ratio of the second solvent to the mesoporous silica nanospheres was 350:1. Then, a second catalyst, a structure protectant, and a buffer solution were added to the hydrothermal reactor. The second catalyst was 4-dimethylaminopyridine, the structure protectant was hexadecyltrimethylammonium bromide, and the buffer solution was a sodium carbonate-sodium bicarbonate buffer solution. The mass ratio of the second catalyst to the mesoporous silica nanospheres was 0.8:1, and the mass ratio of the structure protectant to the mesoporous silica nanospheres was 0.5:1. After adjusting the pH of the solution in the hydrothermal reactor to 10.0 using the sodium carbonate-sodium bicarbonate buffer solution, the reaction was carried out in the hydrothermal reactor at 300°C for 3 days. After the reaction, the product was centrifuged, washed, and spray-dried to obtain Sample 3. Sample 3 is a spiked-mesoporous silica nanosphere with open mesoporous channels radiating from the center and rigid nanospikes uniformly distributed on the outer surface. A transmission electron microscope image of sample 3 is shown below. Figure 5 The scanning electron microscope image of sample 3 is shown below. Figure 6 .

[0069] Sample 3 was added to commercially available Dow Corning 184 elastomer (component A and component B were added in a mass ratio of 10:1) to obtain elastomer sample 2. Tensile tests were then performed on elastomer sample 2. The results are shown below. Figure 15 The stress is close to 6.6 MPa. In this example, the addition percentage of sample 3 is 2.5%. Example 3

[0070] Sample 2 obtained in Example 1 was added to commercially available PVB resin (PVB and plasticizer were mixed at a mass ratio of 80:20) to obtain resin sample 3. Tensile tests were performed on resin sample 3, and the results are shown in […]. Figure 20 In this example, the addition percentage for sample 2 is 2.5%.

[0071] Comparative Example 1

[0072] Tensile tests were performed directly using commercially available Dow Corning 184 elastomer (component A and component B were added in a 10:1 mass ratio). Results are shown below. Figure 9 Cyclic tensile testing was performed, and the results are shown below. Figure 10 Commercially available Dow Corning 184 elastomer is labeled as elastomer sample 4.

[0073] Comparative Example 2

[0074] Commercially available silica (silica nanomaterial) was added to commercially available Dow Corning 184 elastomer (component A and component B were added in a mass ratio of 10:1) to obtain elastomer sample 5. Tensile tests were performed on elastomer sample 5, and the results are shown below. Figure 11 In this example, the percentage of commercially available silica added is 2.5%.

[0075] Comparative Example 3

[0076] The sample 1 obtained in Example 1 was added at a percentage of 2.5% to commercially available Dow Corning 184 elastomer (component A and component B were added in a mass ratio of 10:1) to obtain elastomer sample 6. Tensile tests were performed on elastomer sample 6, and the results are shown in […]. Figure 12 .

[0077] Comparative Example 4

[0078] Tensile tests were performed directly using commercially available PVB resin (PVB and plasticizer mixed at a mass ratio of 80:20). Results are shown below. Figure 18 Commercially available PVB resin is designated as resin sample 7.

[0079] Comparative Example 5

[0080] Commercially available silica (silica nanomaterial) was added at a ratio of 2.5% to commercially available PVB resin (PVB and plasticizer were mixed at a mass ratio of 80:20) to obtain resin sample 8. Tensile tests were performed on resin sample 8, and the results are shown in [Figure 8]. Figure 19 .

[0081] Through Example 1, Figure 1 , Figure 2 It is known that the non-spiky mesoporous silica nanospheres synthesized in this invention have large mesoporous channels with a centrally divergent surface.

[0082] Through Example 1, Figure 3 , Figure 4 It is known that the spiked mesoporous silica nanospheres synthesized in this invention have large mesoporous channels with open surfaces radiating from the center, while also having uniformly distributed rigid spikes.

[0083] Through Example 2, Figure 5 , Figure 6 It is known that the height of the rigid protrusions on the surface of the spiked mesoporous silica nanospheres synthesized in this invention can be controlled by adjusting the reaction temperature.

[0084] By comparing Example 1, Figure 7 It can be seen that elastomer sample 4 has good transparency; through Example 1, Figure 8 It is known that adding 2.5% of spiked-mesoporous silica nanospheres to the existing Dow Corning 184 elastomer does not significantly reduce transparency.

[0085] By comparing Example 1, Figure 9 It can be seen that the stress in elastomer sample 4 reaches 3 MPa; through comparative example 2, Figure 11It is known that adding 2.5% silica (silica nanomaterial) to the existing Dow Corning 184 elastomer slightly improves the stress to about 3.5 MPa.

[0086] By comparing Example 3, Figure 12 It can be seen that adding burr-free, smooth-surfaced mesoporous silica nanospheres (sample 1) resulted in a stress of approximately 3.7 MPa; through Example 1, Figure 13 It can be seen that the addition of spiked mesoporous silica nanospheres (sample 2) resulted in a stress of 7 MPa and a strain of approximately 5.1, both of which were significantly improved. This was demonstrated in Example 2. Figure 15 It can be seen that adding spiked mesoporous silica nanospheres (sample 3) resulted in a stress of 6.6 MPa and a strain of about 2.2, which was not as good as sample 2. This shows that different spike heights have an impact on the properties of the elastomer.

[0087] By comparing Example 1, Figure 10 It can be seen that elastomer sample 4 has good cycle performance; through Example 1, Figure 14 It can be seen that the cycling performance of elastomer sample 1 was further improved after adding the spiked-mesoporous silica nanospheres.

[0088] By comparing Example 4, Figure 16 It can be seen that resin sample 7 has good transparency; through Example 3, Figure 17 It can be seen that adding 2.5% of spiked-mesoporous silica nanospheres to existing PVB resin does not significantly reduce transparency.

[0089] By comparing Example 4, Figure 18 It can be seen that the stress in resin sample 7 reaches 24 MPa; through comparative example 5, Figure 19 It can be seen that adding 2.5% silica (silica nanomaterial) to existing PVB resin does not significantly increase the stress to around 24 MPa, while the elongation at break decreases slightly; through Example 3, Figure 20 It can be seen that the stress of resin sample 3 is significantly increased, reaching about 45 MPa; at the same time, the elongation at break reaches 300%, which is slightly improved.

[0090] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing spiked mesoporous silica nanospheres, characterized in that, Includes the following steps: Step 1: Add the template agent and the first catalyst to deionized water as the aqueous phase, and add the silicon source to the first solvent as the oil phase. The aqueous phase and the oil phase undergo a two-phase reaction under stirring. The product obtained from the reaction is separated and dried to obtain mesoporous silica nanospheres. The template agent is at least one of hexadecyltrimethylammonium bromide, hexadecyltrimethylammonium chloride, sodium dodecyl sulfate, sodium dodecyl sulfonate, and polyethylene oxide-polypropylene oxide-polyethylene oxide triblock copolymer; The first catalyst is at least one of hydroxyethyl ethylenediamine, 2-methylaminoethanol, aminopropanol, aminobutanetriol, serine, triethanolamine, isopropanolamine, phenylglycine, or valine. Step 2: Disperse the mesoporous silica nanospheres in the second solvent, then add the second catalyst and the structure protectant. After that, adjust the pH to 8-11 with a buffer solution and react. The product obtained from the reaction is centrifuged, washed and dried to obtain the spiked-mesoporous silica nanospheres. The second catalyst is at least one of 1,4-diazabicyclo[2.2.2]octane, 1,8-diazabicyclo[5.4.0]undec-7-ene, 1,4-diazabicyclo[2.2.2]octane, 4-dimethylaminopyridine, tetramethylammonium hydroxide, N-methylmorpholine, triethylamine or triethanolamine; The structural protective agent is at least one of polyvinylpyrrolidone, hexadecyltrimethylammonium bromide, polydiallyldimethylammonium chloride, sodium citrate, or polyacrylic acid.

2. The preparation method according to claim 1, characterized in that: In step 1, the template agent has a mass fraction of 5% to 50% in the aqueous phase; And / or, The mass fraction of the first catalyst in the aqueous phase is 0.1~20%.

3. The preparation method according to claim 1, characterized in that: In step 1, the silicon source is at least one of bis(triethoxysilyl)methane, 1,4-bis(triethoxysilyl)benzene, 1,2-bis(triethoxysilyl)ethane, tetramethyl orthosilicate, tetraethyl orthosilicate, tetrapropyl orthosilicate, or sodium silicate. And / or, The silicon source has a mass fraction of 2-50% in the oil phase; And / or, The first solvent is at least one of n-hexane, cyclohexane, or toluene.

4. The preparation method according to claim 1, characterized in that: The mass ratio of the oil phase to the water phase is (0.2~1):

1.

5. The preparation method according to claim 1, characterized in that: In step 1, the temperature of the biphasic reaction is 20~80℃, and the reaction time is 0.5~6 days.

6. The preparation method according to claim 1, characterized in that: In step 2, the second solvent is at least one of tetrahydrofuran, ethanol, deionized water, N,N-dimethylformamide, methanol, or isopropanol; And / or, The second solvent and mesoporous silica nanospheres are added at a mass ratio of (100~500):1; And / or, The second catalyst is present in a mass ratio of (0.5~5):1 with mesoporous silica nanospheres; And / or, The mass ratio of the structural protective agent to the mesoporous silica nanospheres is (0.4~6):1; And / or, The buffer solution is one of ammonia-ammonium chloride buffer solution, sodium carbonate-sodium bicarbonate buffer solution, or glycine-sodium hydroxide buffer solution; And / or, The reaction temperature in step 2 is 50~350℃, and the reaction time is 0.5~7 days.

7. A spiked-mesoporous silica nanosphere, characterized in that: The spiked-mesoporous silica nanospheres are prepared by the preparation method according to any one of claims 1 to 6.

8. The spiked-mesoporous silica nanospheres according to claim 7, characterized in that: The spiked-mesoporous silica nanospheres have a particle size of 50~100nm, and the mesoporous channels of the spiked-mesoporous silica nanospheres have a centrally divergent structure with a pore size of 6~8nm and an open surface. The surface of the spiked-mesoporous silica nanospheres has a spike structure with a height of 3~5nm.

9. The application of the spiked-mesoporous silica nanospheres as described in claim 7 or 8 in the reinforcement and toughening of polymer materials.

10. The application according to claim 9, characterized in that: The polymeric material includes elastomers or resins.

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