Multi-structured functional epoxy resin microspheres, method for preparing the same and toughening and reinforcing applications

Abstract

The application discloses a kind of multi-structure functional epoxy resin microspheres and its preparation method and toughening and reinforcing applications.The preparation method of the epoxy resin microspheres of the application includes the following steps: mixture A, mixture B and mixture C are reacted under the action of catalyst to obtain the multi-structure functional epoxy resin microspheres;The mixture A is prepared by dispersing or dissolving a surfactant in solvent A, or by dispersing or dissolving a surfactant and a stabilizer in solvent A;The mixture B is prepared by mixing epoxy resin with solvent B and then heating;The mixture C is prepared by dissolving a curing agent in solvent C.The application uses a "one-pot method" to prepare epoxy resin microspheres, the preparation process is simple, the obtained microspheres are highly cross-linked, have amino, epoxy or hydroxyl functional groups on the surface, and have non-porous, porous, hollow, raspberry-like or semi-hollow snowman-like multi-structure, and can be used for simultaneous toughening and reinforcing of epoxy resin and cement.

Description

Technical Field

[0001] This invention relates to the field of epoxy resin technology, specifically to a multi-structured functional epoxy resin microsphere, its preparation method, and its reinforcing and toughening applications in epoxy resins and cement. Background Technology

[0002] Epoxy resin possesses a highly cross-linked network structure, giving it excellent properties such as high strength, high thermal stability, and corrosion resistance. However, it also suffers from insufficient toughness and high brittleness, limiting its widespread application in construction, aerospace, and electronics. Similarly, oil well cement has high strength but also suffers from high brittleness and small deformation, making it prone to micro-cracks and failure. To improve the toughness of epoxy resin and cement, inorganic, organic hard particles or organic elastic particles are added. However, this method still suffers from weak interfacial bonding between particles and the matrix, resulting in a decrease in strength while increasing toughness. Utilizing epoxy microspheres to self-toughen epoxy resin substrates avoids interfacial problems, but requires the use of highly cross-linked (Tg>200℃) hard epoxy microspheres to achieve improved toughness without a significant decrease in strength. Considering the excellent properties of epoxy resin, there are reports on using elastic and tough epoxy particle powder and elastic and tough core (epoxy resin / polyamide)-hard shell (SiO2) composite microspheres to toughen cement. However, while the above methods improve the toughness and deformation capacity of cement stone, they also lead to a decrease in elastic modulus and compressive strength. How to effectively improve the toughness and strength of cement stone at the same time is still a technical problem that urgently needs to be solved.

[0003] Epoxy resin microspheres are thermosetting polymer microspheres formed by reacting epoxy resin and a curing agent as monomers. They can currently be prepared using methods such as emulsion polymerization, phase-inversion emulsion polymerization, suspension polymerization, dispersion polymerization, and precipitation polymerization (reaction-induced phase separation). For example, emulsion polymerization can be carried out using epoxy resin, reactive diluent, and liquid imidazole curing agent (Chinese invention patent CN101074311A) in an aqueous system containing an emulsifier; suspension polymerization can be carried out by dispersing epoxy resin, diluent, and amine curing agent in water containing polyvinyl alcohol (PVA) and sodium dodecyl sulfonate (SDS) as a dispersant and stabilizer; and epoxy resin, curing agent, organic solvent (methyl isobutyl ketone), emulsifier (hexadecyltrimethylammonium bromide, Span 80), and liquid rubber can be mixed evenly, pre-cured, and then the resulting product is stirred. Deionized water is slowly added to achieve phase inversion and stabilize the emulsion, and then the reaction continues until complete (Chinese Invention Patent CN108129605A) to obtain epoxy resin microspheres; using phase inversion emulsion polymerization, toughening monomers with good flexibility and aging resistance, such as acrylates, organosiloxanes containing double bonds, and oligomeric polyamide 650, are added in situ to the epoxy resin curing system to prepare epoxy resin microsphere materials with good flexibility (Chinese Invention Patents CN107880492A, CN108047653A); or phase inversion emulsification technology is used to obtain water / oil (epoxy) / water or water / epoxy / ethylene glycol dual emulsions of epoxy resin (Chinese Invention Patent CN102850521A), and then porous or hollow epoxy resin microspheres are obtained by reacting with a small amount of curing agent and removing water. These microspheres have good impact resistance but low strength. When used for epoxy toughening, they often result in a decrease in strength while achieving a good toughening effect.

[0004] Epoxy resin and curing agent can be precipitated or dispersed in epoxidized soybean oil or liquid crystal, or mixed uniformly with thermoplastic polymers such as polyester, polyether diol (e.g., polypropylene glycol PPG600), polytetrahydrofuran polyol (PTG), polylactic acid (PCL), etc., and phase separation can be induced during the curing and crosslinking reaction to form rigid epoxy resin microspheres with narrow particle size distribution, smooth surface, and high crosslinking (Tg>200℃). However, the above preparation process is complicated, especially requiring the use of a large amount of organic solvent to elute the microspheres, and the yield of microspheres is not high, which affects the promotion and use. Summary of the Invention

[0005] The purpose of this invention is to address the problem of effectively improving both toughness and strength simultaneously during the toughening and modification of epoxy resin and cementitious substrates. This invention provides a multi-structured functional epoxy resin microsphere and its preparation method. Furthermore, this invention also provides applications of the obtained microspheres in the toughening and reinforcement of epoxy resin and cement. This invention utilizes a one-pot method to prepare epoxy resin microspheres, which is simple. The microspheres are highly cross-linked (high Tg) and contain amino, epoxy, or hydroxyl functional groups on their surface. This allows for the preparation of non-porous, porous, hollow, raspberry-like, or semi-hollow snowman-like multi-structured epoxy resin microspheres. The microspheres can be firmly bonded to epoxy and cement substrates through chemical bonding via surface functional groups. The pores and protrusions on the surface of the microspheres can form a mechanical interlock with the substrate. By inducing interfacial creasing and exerting a pinning effect, the toughness and strength of the material can be improved simultaneously. Test results show that using the microspheres obtained by this invention to toughen epoxy resin can significantly improve the impact strength, tensile strength and elongation at break of epoxy resin. Using the microspheres obtained by this invention to toughen cement can significantly improve the compressive strength, flexural strength, ultimate strain and toughness modulus of cement paste.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention protects a method for preparing epoxy resin microspheres, comprising the following steps:

[0008] Mixture A, mixture B, and mixture C are reacted under the action of a catalyst to obtain the multi-structured functional epoxy resin microspheres;

[0009] The mixture A is prepared by dispersing or dissolving a surfactant in solvent A, or by dispersing or dissolving a surfactant and a stabilizer in solvent A;

[0010] The mixture B is prepared by heating a mixture of epoxy resin and solvent B.

[0011] The mixture C is prepared by dissolving a curing agent in solvent C.

[0012] In the above-mentioned method for preparing epoxy resin microspheres, the multi-structured functional epoxy resin microspheres include non-porous, porous, hollow, raspberry-shaped, or semi-hollow snowman-shaped multi-structured epoxy resin microspheres.

[0013] The surface of the epoxy resin microspheres contains one or two of amino, hydroxyl and epoxy groups, but not both amino and epoxy groups at the same time. For example, it contains amino and hydroxyl groups or contains epoxy and hydroxyl groups. The residual groups on the surface of the microspheres after the reaction are affected by the ratio of epoxy and curing agent.

[0014] The particle size of the multi-structured functional epoxy resin microspheres is 7.3–1116 μm, specifically the average particle size analyzed by a laser particle size analyzer.

[0015] The glass transition temperature (Tg) of the multi-structured functional epoxy resin microspheres is 124–168 °C.

[0016] In the above-mentioned method for preparing epoxy resin microspheres, the epoxy resin is selected from at least one of diepoxy monomers, triepoxy monomers, and tetraepoxy monomers.

[0017] Based on 100 parts by weight of the epoxy resin, the triepoxy monomer or the tetraepoxy monomer is 0 to 10 parts by weight, including but not limited to 0 parts, 10 parts or 5 parts.

[0018] The preferred diepoxy monomer is bisphenol A diglycidyl ether E51 (epoxy resin E51) or bisphenol A diglycidyl ether E44 (epoxy resin E44).

[0019] The preferred triepoxide monomer is trimethylolpropane triglycidyl ether (TMTGE).

[0020] The tetracyclic epoxy monomer is preferably 4,4-diaminodiphenylmethane tetraglycidylamine (TGMDA).

[0021] In the above-mentioned method for preparing epoxy resin microspheres, the surfactant is a nonionic surfactant, including one of polyvinylpyrrolidone (such as PVP30K), polyvinyl alcohol (such as PEG200), and benzyl benzoate.

[0022] When only a surfactant is added to the mixture A, the surfactant is 35 to 140 parts by mass, including but not limited to 140 parts, 35 parts, or 80 parts, based on 100 parts by mass of the epoxy resin.

[0023] The stabilizer is SiO2 nanoparticles or nanosheets with amino, epoxy, or hydroxyl groups on their surface.

[0024] When a surfactant and a stabilizer are added to the mixture A, based on 100 parts by mass of the epoxy resin, the surfactant and the stabilizer are 35 to 140 parts by mass, including but not limited to 70 parts, and the stabilizer is 0.08 to 1.6 parts by mass, including but not limited to 0.08 parts.

[0025] In the above-mentioned method for preparing epoxy resin microspheres, the curing agent is a polyamine curing agent, selected from one or more of ethyleneamine, polyetheramine, alicyclic amine, aromatic amine and curing agents containing disulfide bonds;

[0026] The acetamide is preferably triethylenetetramine (TETA);

[0027] The polyetheramine is preferably polypropylene glycol di(2-aminopropyl) ether (polyetheramine D230);

[0028] The preferred alicyclic amine is isophorone diamine (IPDA);

[0029] The aromatic amine is preferably 4,4'-diaminodiphenylmethane (DDM) or diethyltoluenediamine (DETDA);

[0030] The curing agent containing disulfide bonds is preferably 4,4'-dithiodiphenylamine (DTDA);

[0031] Based on 100 parts by weight of the epoxy resin, the curing agent is 15 to 35 parts by weight, including but not limited to 35 parts, 15 parts, or 25 parts.

[0032] In the above-mentioned method for preparing epoxy resin microspheres, solvent A is organic solvent a and / or water;

[0033] Solvent B is organic solvent b and / or water;

[0034] The solvent C is an organic solvent c and / or water;

[0035] The organic solvent a, organic solvent b, and organic solvent c are organic alcohols, ketones, or alkanes; the organic alcohol is preferably ethanol; the ketone is preferably acetone; and the alkanes are preferably n-hexane.

[0036] In solvent A, based on 100 parts by mass of epoxy resin, the organic solvent a has a mass of 0 to 493 parts by mass, and the water has a mass of 0 to 625 parts by mass, but the two are not both 0 at the same time;

[0037] In solvent b, based on 100 parts by mass of epoxy resin, the organic solvent b comprises 78 to 493 parts by mass, and the water comprises 0 to 625 parts by mass.

[0038] In solvent c, based on 100 parts by mass of epoxy resin, the organic solvent c comprises 78 to 493 parts by mass, and the water comprises 0 to 625 parts by mass.

[0039] In the above-mentioned method for preparing epoxy resin microspheres, the catalyst is a tertiary amine catalyst, including one of 1,8-diazabicycloundec-7-ene (DBU), benzyl dimethylamine (BDMA), and 2,4,6-tris(dimethylaminomethyl)phenol (DMP-30);

[0040] Based on 100 parts by weight of the epoxy resin, the amount of the catalyst is 1 to 5 parts, including but not limited to 5 parts, 1.25 parts, 2.5 parts, 1.5 parts or 1 part.

[0041] In the above-mentioned method for preparing epoxy resin microspheres, the reaction is carried out under stirring conditions, and the stirring speed is 300-500 rpm, such as 500 r / min.

[0042] The reaction temperature is 60–90°C and the time is 4–6 hours, such as reacting at 90°C or 60°C for 6 hours;

[0043] The preparation process further includes the following steps after the reaction is complete: centrifuging the reaction solution to collect the solid product, then washing with ethanol, centrifuging again, and drying.

[0044] Secondly, the present invention protects epoxy resin microspheres obtained by the preparation method of epoxy resin microspheres described in any of the above claims.

[0045] Thirdly, the present invention protects the application of the epoxy resin microspheres in the toughening and reinforcement of epoxy resin or cement.

[0046] In the above applications, the toughening and strengthening of epoxy resin is reflected in simultaneously improving the toughness and strength of epoxy resin, specifically by simultaneously improving the impact strength, tensile strength and elongation at break of epoxy resin.

[0047] The toughening and strengthening effect in cement is reflected in the simultaneous improvement of the toughness and strength of cement paste, specifically in the simultaneous improvement of the compressive strength, flexural strength, ultimate strain and toughness modulus of cement paste.

[0048] In the above applications, the toughening and reinforcement in epoxy resin includes the following steps: preparing a modified epoxy resin by combining epoxy resin monomers, epoxy resin microspheres, and a curing agent.

[0049] Preferably, based on 100 parts by weight of epoxy resin monomer, the number of parts by weight of epoxy resin microspheres is 0.5 to 8 parts, including but not limited to 5 parts, 2 parts, 4 parts or 0.5 parts;

[0050] As a test example, with 100 parts by weight of epoxy resin monomer, the curing agent is 15 to 35 parts by weight, including but not limited to 26 or 35 parts.

[0051] As a test example, the preparation steps are as follows: the obtained microspheres are added to the epoxy resin monomer, heated to 70°C, stirred for 2 hours at a speed of 120 r / min, a curing agent is added, and stirred to obtain an epoxy resin reaction solution; the epoxy resin reaction solution is poured into an 80°C preheated mold, and cured by heating at 80°C×1h+100°C×1h+130°C×1h, and then naturally cooled to room temperature to obtain modified epoxy resin.

[0052] In the above applications, the toughening and strengthening in cement includes the following steps: preparing cement slurry by mixing cement ash, the epoxy resin microspheres and water, and curing the cement slurry to obtain cement stone.

[0053] Preferably, based on 100 parts by weight of cement ash, the epoxy resin microspheres are 5 to 10 parts by weight, including but not limited to 10 parts, 5 parts, 8 parts or 6 parts.

[0054] As a test example, the preparation steps are as follows: add the epoxy resin microspheres to G-grade cement ash, add water, shake and homogenize to obtain cement slurry; put the cement slurry into a hydrothermal reactor, cure it in an oven at 95℃ for 1 day, and then cure it in a constant temperature water at 95℃ for 6 days.

[0055] The present invention has the following beneficial effects:

[0056] (1) The present invention utilizes a “one-pot method” to prepare functional epoxy resin microspheres with multiple structures (non-porous, porous, hollow, raspberry-like, semi-hollow snowman-like) and containing amino, hydroxyl or epoxy on the surface, and the process is simple;

[0057] (2) The microspheres obtained in this invention can be used to toughen epoxy resin, which can significantly improve the impact strength, tensile strength and elongation at break of epoxy resin at the same time. Compared with the blank sample without epoxy resin microspheres, the epoxy resin sample with epoxy resin microspheres can improve the impact strength by 23-70%, the tensile strength by 19-35%, and the elongation at break by 43-107%. The epoxy resin microspheres of this invention can improve the toughness and strength of epoxy resin at the same time, achieving simultaneous toughening and strengthening of epoxy resin.

[0058] (3) The microspheres obtained by the present invention can be used to toughen cement, which can significantly improve the compressive strength, flexural strength, ultimate strain and toughness modulus of cement stone. Compared with blank cement stone without epoxy microspheres, the cement stone made by adding epoxy microspheres has a 16-40% increase in compressive strength, a 29-57% increase in flexural strength, a 113-193% increase in ultimate strain and a 21-72% increase in toughness modulus. The epoxy resin microspheres of the present invention can simultaneously improve the toughness and strength of cement, and achieve simultaneous toughening and strengthening of cement. Attached Figure Description

[0059] Figure 1 (a) SEM images of the non-porous epoxy microspheres prepared in Examples 1, 4, and 5. Figure 1 (b) shows the non-porous epoxy microspheres prepared in Examples 2 and 3;

[0060] Figure 2 (a) is a SEM image of the raspberry-like epoxy microspheres prepared in Example 6. Figure 2 (b) SEM image of the raspberry-shaped epoxy microspheres prepared in Example 8;

[0061] Figure 3 SEM image of the porous epoxy microspheres prepared in Example 7;

[0062] Figure 4 SEM image of the semi-hollow snowman-shaped epoxy microspheres prepared in Example 9;

[0063] Figure 5 (a) and (b) are SEM images of the hollow epoxy microspheres prepared in Example 10;

[0064] Figure 6 This is a SEM image of the raspberry-shaped hollow epoxy microspheres prepared in Example 11. Detailed Implementation

[0065] The present invention will now be described in further detail with reference to specific embodiments. The given embodiments are merely illustrative of the invention and not intended to limit its scope. The embodiments provided below can serve as a guide for further improvements by those skilled in the art and do not constitute a limitation on the invention in any way.

[0066] Unless otherwise specified, the methods used in the following embodiments are conventional methods, performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Unless otherwise specified, the materials and reagents used in the following embodiments are commercially available.

[0067] The SiO2 nanoparticles with functional groups on their surface in the following examples are from the Henan Nanomaterials Engineering Technology Research Center, DL-A20, 20nm; the SiO2 nanosheets with functional groups on their surface are from the Henan Nanomaterials Engineering Technology Research Center, DL-NP-10, 2×30μm×10nm.

[0068] In the following examples, the surfactant PVP is polyvinylpyrrolidone PVP30K, MREDA M056871, the PEG is polyvinyl alcohol PEG200, AC13798, and the benzyl maleic anhydride resin is styrene maleic anhydride resin, J-3000.

[0069] In the following examples, the particle morphology was observed using a scanning electron microscope (SEM); the particle size of the epoxy microspheres was measured using a Mastersizer 2000 laser diffractometer (Malvern Instruments Ltd.); and the glass transition temperature (Tg) of the epoxy resin microspheres was tested using differential scanning calorimetry (DSC).

[0070] Example 1

[0071] This embodiment provides the preparation of multi-structured functional epoxy resin microspheres and their toughening and strengthening effects in epoxy resin.

[0072] I. Preparation

[0073] The specific steps for preparing epoxy resin microspheres are as follows:

[0074] S1. Add 5.6g PVP to a centrifuge tube and add 20mL ethanol to obtain mixture A; add 4g epoxy resin E51 to a centrifuge tube and add 8mL ethanol to mix, then heat to 50℃ to obtain mixture B; add 1.4g curing agent DDM to a centrifuge tube and add 12mL ethanol to dissolve DDM to obtain mixture C.

[0075] S2. Add mixture A to a three-necked flask, turn on mechanical stirring at 500 rpm, heat to 90°C in a water bath, then add mixtures B and C, and add 0.2 g of catalyst DBU. React for 6 hours, allow to cool naturally, centrifuge, then wash with ethanol, centrifuge three times, and dry to obtain a product with amino and hydroxyl groups on the surface, as shown in the attached... Figure 1 (a) shows the non-porous epoxy microspheres.

[0076] In this embodiment, the average particle size of the microspheres was analyzed by laser particle size analyzer to be 11.9 μm, and the glass transition temperature was measured by DSC to be 164 °C.

[0077] II. Epoxy Resin Toughening and Reinforcement

[0078] The epoxy resin microspheres prepared above are used to toughen epoxy resin. The specific steps are as follows:

[0079] Add 1.0g of the obtained microspheres to 20g of E51 monomer, heat to 70℃, stir for 2h at 120r / min, then add 5.2g of curing agent IPDA and stir for 5min; pour the prepared epoxy resin reaction solution into an 80℃ preheated mold, place it in an oven, and cure it by increasing the temperature at 80℃×1h+100℃×1h+130℃×1h. Allow it to cool naturally to room temperature to obtain the modified epoxy resin sample.

[0080] According to GB / T1040.4-2006, the tensile and impact properties of epoxy resin specimens were determined. Five samples were tested each time, and the average value was taken. Epoxy resin without added particles was used as a blank sample. The test results are shown in Table 1.

[0081] As shown in Table 1, compared with the blank sample without microspheres, the epoxy resin with added microspheres showed an increase of 70% in impact strength, 35% in tensile strength, and 107% in elongation at break.

[0082] Example 2

[0083] As in Example 1, except that in the microsphere preparation process, the amount of surfactant PVP used was 1.4g, the amount of curing agent DDM was 0.6g, the organic solvent used was acetone, the stirring speed was 300r / min, the temperature was raised to 60℃ for reaction, and then mixtures B and C were added, and 0.05g of catalyst DBU was added. The specific steps are as follows:

[0084] S1. Add 1.4g PVP to a centrifuge tube and add 20mL acetone to obtain mixture A; add 4g epoxy resin E51 to a centrifuge tube and add 8mL acetone to mix, then heat to 50℃ to obtain mixture B; add 0.6g curing agent DDM to a centrifuge tube and add 12mL acetone to dissolve DDM to obtain mixture C.

[0085] S2. Add mixture A to a three-necked flask, turn on mechanical stirring at 300 rpm, heat to 60°C in a water bath, then add mixtures B and C, and add 0.05 g of catalyst DBU. React for 6 hours, allow to cool naturally, centrifuge, wash with ethanol, centrifuge three times, and dry to obtain a surface containing epoxy groups and hydroxyl groups, as shown in the attached figure. Figure 1 (b) shows the non-porous epoxy microspheres.

[0086] In this embodiment, the average particle size of the obtained microspheres is 247.5 μm, and the glass transition temperature Tg is 124 °C.

[0087] As in Example 1, 0.5g of the obtained microspheres were added to the E51 and IPDA curing system to prepare epoxy resin samples. The specific steps are as follows:

[0088] Add 0.5g of the obtained microspheres to 20g of E51 monomer, heat to 70℃, stir for 2h at 120r / min, then add 5.2g of curing agent IPDA and stir for 5min; pour the prepared epoxy resin reaction solution into an 80℃ preheated mold, place it in an oven, and cure it by increasing the temperature from 80℃×1h+100℃×1h+130℃×1h. Allow it to cool naturally to room temperature to obtain the modified epoxy resin sample.

[0089] According to GB / T1040.4-2006, the tensile and impact properties of epoxy resin specimens were determined. Five samples were tested each time, and the average value was taken. Epoxy resin without added particles was used as a blank sample. The test results are shown in Table 1.

[0090] As shown in Table 1, compared with the blank sample without microspheres, the epoxy resin with added microspheres showed an increase of 39% in impact strength, 14% in tensile strength, and 48% in elongation at break.

[0091] Example 3

[0092] As in Example 1, except that in the microsphere preparation process, the amount of surfactant PVP used is 3.2g, the amount of curing agent DDM is 1.4g, the stirring speed is 300r / min, the temperature is raised to 80℃ for reaction, and 0.1g of catalyst DBU is added. The specific steps are as follows:

[0093] S1. Add 3.2g PVP to a centrifuge tube and add 20mL ethanol to obtain mixture A; add 4g epoxy resin E51 to a centrifuge tube and add 8mL ethanol to mix, then heat to 80℃ to obtain mixture B; add 1.4g curing agent DDM to a centrifuge tube and add 12mL ethanol to dissolve DDM to obtain mixture C.

[0094] S2. Add mixture A to a three-necked flask, turn on mechanical stirring at 300 rpm, heat to 60°C in a water bath, then add mixtures B and C, and add 0.1 g of catalyst DBU. React for 6 hours, allow to cool naturally, centrifuge, then wash with ethanol, centrifuge three times, and dry to obtain a product with amino and hydroxyl groups on the surface, as shown in the attached... Figure 1 (b) shows the non-porous epoxy microspheres.

[0095] In this embodiment, the average particle size of the obtained microspheres is 60.5 μm, and the glass transition temperature Tg is 138 °C.

[0096] As in Example 1, 1.5g of the obtained microspheres were added to the E51 and IPDA curing system to prepare epoxy resin samples. The specific steps are as follows:

[0097] Add 1.5g of the obtained microspheres to 4g of E51 monomer, heat to 70℃, stir for 2h at 120r / min, then add 5.2g of curing agent IPDA and stir for 5min; pour the prepared epoxy resin reaction solution into an 80℃ preheated mold, place it in an oven, and cure it by increasing the temperature at 80℃×1h+100℃×1h+130℃×1h. Allow it to cool naturally to room temperature to obtain the modified epoxy resin sample.

[0098] According to GB / T1040.4-2006, the tensile and impact properties of epoxy resin specimens were determined. Five samples were tested each time, and the average value was taken. Epoxy resin without added particles was used as a blank sample. The test results are shown in Table 1.

[0099] As shown in Table 1, compared with the blank sample without microspheres, the epoxy resin with added microspheres showed an increase of 47% in impact strength, 31% in tensile strength, and 80% in elongation at break.

[0100] Example 4

[0101] As in Example 1, except that the surfactant used in the microsphere preparation process is PEG200 (1.3g), the epoxy resin is E44 (3.6g) and TMTGE (0.4g), the curing agent is TETA (0.6g), and the catalyst is BDMA (0.06g). The specific steps are as follows:

[0102] S1. Add 1.3g PEG200 to a centrifuge tube and add 20mL ethanol to obtain mixture A; add 3.6g epoxy resin E44 and 0.4g TMTGE to a centrifuge tube, add 8mL ethanol to mix, and heat to 50℃ to obtain mixture B; add 0.6g curing agent TETA to a centrifuge tube, add 12mL ethanol to dissolve TETA, and obtain mixture C;

[0103] S2. Add mixture A to a three-necked flask, turn on mechanical stirring at 500 rpm, heat to 90°C in a water bath, then add mixtures B and C, and add 0.06 g of catalyst BDMA. React for 6 hours, allow to cool naturally, centrifuge, wash with ethanol, centrifuge three times, and dry to obtain a surface containing epoxy and hydroxyl groups, as shown in the attached image. Figure 1 (a) shows the non-porous epoxy microspheres.

[0104] In this embodiment, the average particle size of the obtained microspheres is 7.3 μm, and the Tg is 131 °C.

[0105] As in Example 1, epoxy resin samples were prepared using the following steps: 0.1g of the obtained microspheres were added to 20g of E51 monomer, the temperature was raised to 70℃, and the mixture was stirred for 2 hours at a speed of 120r / min. Then, 5.2g of curing agent IPDA was added and stirred for 5 minutes. The prepared epoxy resin reaction solution was poured into a preheated mold at 80℃, placed in an oven, and cured by heating at 80℃×1h+100℃×1h+130℃×1h. The mixture was then allowed to cool naturally to room temperature to obtain the modified epoxy resin sample.

[0106] According to GB / T1040.4-2006, the tensile and impact properties of epoxy resin specimens were determined. Five samples were tested each time, and the average value was taken. Epoxy resin without added particles was used as a blank sample. The test results are shown in Table 4.

[0107] As shown in Table 1, compared with the blank sample without microspheres, the epoxy resin with added microspheres showed an increase of 23% in impact strength, 20% in tensile strength, and 64% in elongation at break.

[0108] Example 5

[0109] As in Example 1, except that in the microsphere preparation process, the surfactant used is benzyl benzoate resin (1.4g), the epoxy resin is E51 (3.8g) and TGMDA (0.2g), the amount of curing agent polyetheramine D230 is 1g, and the catalyst DMP-30 (0.04g) is added. The specific steps are as follows:

[0110] S1. Add 1.4g of benzyl benzoate resin to a centrifuge tube and add 20mL of ethanol to obtain mixture A; add 3.8g of epoxy resin E51 and 0.2g of TGMDA to a centrifuge tube, add 8mL of ethanol to mix, and heat to 50℃ to obtain mixture B; add 1g of curing agent D230 to a centrifuge tube and add 12mL of ethanol to dissolve D230 to obtain mixture C;

[0111] S2. Add mixture A to a three-necked flask, turn on mechanical stirring at 500 rpm, heat to 90°C in a water bath, then add mixtures B and C, and add 0.04 g of catalyst DMP-30. React for 6 hours, allow to cool naturally, centrifuge, then wash with ethanol, centrifuge three times, and dry to obtain a product with amino and hydroxyl groups on the surface, as shown in the attached... Figure 1 (a) shows the non-porous epoxy microspheres.

[0112] In this embodiment, the average particle size of the microspheres was analyzed by laser particle size analyzer to be 23.7 μm, and the glass transition temperature was measured by DSC to be 137.21℃.

[0113] As in Example 1, epoxy resin samples were prepared using the following steps: 1g of the obtained microspheres were added to 20g of E51 monomer, the temperature was raised to 70℃, and the mixture was stirred for 2 hours at a speed of 120r / min. Then, 5.2g of curing agent IPDA was added and stirred for 5 minutes. The prepared epoxy resin reaction solution was poured into a preheated mold at 80℃, placed in an oven, and cured by heating at 80℃×1h+100℃×1h+130℃×1h. The mixture was then allowed to cool naturally to room temperature to obtain modified epoxy resin samples.

[0114] According to GB / T1040.4-2006, the tensile and impact properties of epoxy resin specimens were determined. Five samples were tested each time, and the average value was taken. Epoxy resin without added particles was used as a blank sample. The test results are shown in Table 1.

[0115] As shown in Table 1, compared with the blank sample without microspheres, the epoxy resin with added microspheres showed an increase of 58% in impact strength, 33% in tensile strength, and 95% in elongation at break.

[0116] Example 6

[0117] As in Example 1, except that the surfactant used in the microsphere preparation process is PVP (5.6g), and the stabilizer SiO2 nanoparticles (0.06g) are also added, and the curing agent DTDA (1g) is used. The specific steps are as follows:

[0118] S1. Add 5.6g PVP and 0.06g stabilizer SiO2 nanoparticles (containing amino groups on the surface, 20nm) to a centrifuge tube, add 20mL ethanol to obtain mixture A; add 4g epoxy resin E51 to a centrifuge tube, add 8mL ethanol to mix, heat to 50℃ to obtain mixture B; add 1g curing agent DTDA to a centrifuge tube, add 12mL ethanol to dissolve DDM to obtain mixture C;

[0119] S2. Add mixture A to a three-necked flask, turn on mechanical stirring at 500 rpm, heat to 90°C in a water bath, then add mixtures B and C, and add 0.2 g of catalyst DBU. React for 6 hours, allow to cool naturally, centrifuge, then wash with ethanol, centrifuge three times, and dry to obtain a product with amino and hydroxyl groups on the surface, as shown in the attached... Figure 2 (a) shows raspberry-shaped epoxy microspheres.

[0120] In this embodiment, the average particle size of the microspheres was analyzed by laser particle size analyzer to be 217.5 μm, and the glass transition temperature was measured by DSC to be 153.4 °C.

[0121] As in Example 1, epoxy resin samples were prepared using the following steps: 1g of the obtained microspheres were added to 20g of E51 monomer, the temperature was raised to 70℃, and the mixture was stirred for 2 hours at a speed of 120r / min. Then, 5.2g of curing agent IPDA was added and stirred for 5 minutes. The prepared epoxy resin reaction solution was poured into a preheated mold at 80℃, placed in an oven, and cured by heating at 80℃×1h+100℃×1h+130℃×1h. The mixture was then allowed to cool naturally to room temperature to obtain modified epoxy resin samples.

[0122] According to GB / T1040.4-2006, the tensile and impact properties of epoxy resin specimens were determined. Five samples were tested each time, and the average value was taken. Epoxy resin without added particles was used as a blank sample. The test results are shown in Table 1.

[0123] As shown in Table 1, compared with the blank sample without microspheres, the epoxy resin with added microspheres showed an increase of 23% in impact strength, 19% in tensile strength, and 43% in elongation at break.

[0124] Example 7

[0125] This embodiment provides the preparation of multi-structured functional epoxy resin microspheres and their toughening and strengthening effects in cement.

[0126] I. Preparation

[0127] As in Example 1, except that in the microsphere preparation process, the surfactant PVP used was 1.4g, and 3mL of ethanol was added to obtain mixture A; 3mL of ethanol was added to E51 and mixed to obtain mixture B; 3mL of ethanol was added to DDM to obtain mixture C. The specific steps are as follows:

[0128] S1. Add 1.4g PVP and 3g ethanol to a centrifuge tube to obtain mixture A; add 4g epoxy resin E51 and 3g ethanol to a centrifuge tube, mix, and heat to 50℃ to obtain mixture B; add 1.4g curing agent DDM to a centrifuge tube, add 3g ethanol to dissolve DDM, and obtain mixture C.

[0129] S2. Add mixture A to a three-necked flask, turn on mechanical stirring at 500 rpm, heat to 90°C in a water bath, then add mixtures B and C, and add 0.2 g of catalyst DBU. React for 6 hours, allow to cool naturally, centrifuge, then wash with ethanol, centrifuge three times, and dry to obtain a product with amino and hydroxyl groups on the surface, as shown in the attached... Figure 3 The porous epoxy microspheres shown are shown.

[0130] In this embodiment, the average particle size of the microspheres was analyzed by laser particle size analyzer to be 135.7 μm, and the glass transition temperature was measured by DSC to be 168 °C.

[0131] II. Cement Toughening and Reinforcement

[0132] The epoxy resin microspheres prepared above are used to toughen cement. The specific steps are as follows:

[0133] Add 3g of the obtained microspheres to 30g of G-grade cement ash, add 13mL of water, shake and homogenize for 10min to obtain cement slurry; pour 5 parallel samples into molds, place them in a hydrothermal autoclave, cure in a 95℃ oven for 1 day, and then cure in a 95℃ constant temperature water for 6 days to obtain 5 parallel cement stone blocks.

[0134] The uniaxial compressive and three-point bending mechanical properties of cement were determined according to GB / T 19139–2012. Five samples were tested each time, and the average value was taken. Cement without added particles was used as a blank sample. The test results are shown in Table 2.

[0135] As shown in Table 2, compared with the blank sample without microspheres, the cement stone with added microspheres showed an increase of 16% in compressive strength, 57% in flexural strength, 113% in ultimate strain, and 72% in toughness modulus.

[0136] Example 8

[0137] As in Example 1, except that the surfactant used in the microsphere preparation process is PVP (2.8g), and the stabilizer SiO2 nanosheets (0.3g) and the curing agent is DETDA (0.8g) are also added. The specific steps are as follows:

[0138] S1. Add 2.8g PVP and 0.3g stabilizer SiO2 nanosheets (containing epoxy groups on the surface, 2×30μm×10nm) to a centrifuge tube, add 20mL ethanol to obtain mixture A; add 4g epoxy resin E51 to a centrifuge tube, add 8mL ethanol to mix, heat to 50℃ to obtain mixture B; add 0.8g curing agent DETDA to a centrifuge tube, add 12mL ethanol to dissolve DETDA to obtain mixture C;

[0139] S2. Add mixture A to a three-necked flask, turn on mechanical stirring at 500 rpm, heat to 90°C in a water bath, then add mixtures B and C, and add 0.2 g of catalyst DBU. React for 6 hours, allow to cool naturally, centrifuge, then wash with ethanol, centrifuge three times, and dry to obtain a product with amino and hydroxyl groups on the surface, as shown in the attached... Figure 2 (b) shows raspberry-shaped epoxy microspheres.

[0140] In this embodiment, the average particle size of the microspheres was analyzed by laser particle size analyzer to be 41.9 μm, and the glass transition temperature was measured by DSC to be 1411 °C.

[0141] As in Example 7, cement stone was prepared by adding 5 parts of microspheres. The specific steps are as follows:

[0142] Add 1.5g of the obtained microspheres to 30g of G-grade cement ash, add 13mL of water, shake and homogenize for 10min to obtain cement slurry; pour 5 parallel samples into pre-prepared molds, place them in a hydrothermal reactor, cure in a 95℃ oven for 1 day, and then cure in a 95℃ constant temperature water for 6 days to obtain 5 parallel cement stone blocks.

[0143] The uniaxial compressive and three-point bending mechanical properties of cement were determined according to GB / T 19139–2012. Five samples were tested each time, and the average value was taken. Cement without added particles was used as a blank sample. The test results are shown in Table 2.

[0144] As shown in Table 2, compared with the blank sample without microspheres, the cement stone with added microspheres showed a 40% increase in compressive strength, a 29% increase in flexural strength, a 120% increase in ultimate strain, and a 21% increase in toughness modulus.

[0145] Example 9

[0146] As in Example 1, except that the surfactant used in the microsphere preparation process is PVP, which is dissolved in 20 mL of ethanol and 25 mL of water to obtain mixture A; E51 is mixed with 8 mL of ethanol and 12 mL of water and heated to 50°C to obtain mixture B; the curing agents are DTDA (0.8 g) and TETA (0.2 g), which are added to 5 mL of n-hexane to obtain mixture C. The specific steps are as follows:

[0147] S1. Add 5.6g PVP to a centrifuge tube, add 20mL ethanol and 25mL water to obtain mixture A; add 4g epoxy resin E51 to a centrifuge tube, add 8mL ethanol and 12mL water to mix, heat to 50℃ to obtain mixture B; add 0.8g DTDA and 0.2g TETA curing agent to a centrifuge tube, add 5mL n-hexane to dissolve, to obtain mixture C;

[0148] S2. Add mixture A to a three-necked flask, turn on mechanical stirring at 500 rpm, heat to 90°C in a water bath, then add mixtures B and C, and add 0.2 g of catalyst DBU. React for 6 hours, allow to cool naturally, centrifuge, then wash with ethanol, centrifuge three times, and dry to obtain a product with amino and hydroxyl groups on the surface, as shown in the attached... Figure 4 The image shows a semi-empty, snowman-shaped epoxy microsphere.

[0149] In this embodiment, the average particle size of the microspheres was analyzed by laser particle size analyzer to be 1116.3 μm, and the glass transition temperature was measured by DSC to be 147.6 °C.

[0150] As in Example 7, cement stone was prepared by adding 8 parts of microspheres. The specific steps are as follows:

[0151] Add 2.4g of the obtained microspheres to 30g of G-grade cement ash, add 13mL of water, shake and homogenize for 10min to obtain cement slurry; pour 5 parallel samples into pre-prepared molds, place them in a hydrothermal autoclave, cure in a 95℃ oven for 1 day, and then cure in a 95℃ constant temperature water for 6 days to obtain 5 parallel cement stone blocks.

[0152] The uniaxial compressive and three-point bending mechanical properties of cement were determined according to GB / T 19139–2012. Five samples were tested each time, and the average value was taken. Cement without added particles was used as a blank sample. The test results are shown in Table 2.

[0153] As shown in Table 2, compared with the blank sample without microspheres, the cement stone with added microspheres showed an increase of 36% in compressive strength, 30% in flexural strength, 140% in ultimate strain, and 80% in toughness modulus.

[0154] Example 10

[0155] As in Example 1, except that in the microsphere preparation process, the surfactant used is PVP, which is dissolved in 20 mL of ethanol and 25 mL of water to obtain mixture A; E51 is mixed with 8 mL of ethanol and 12 mL of water and heated to 50°C to obtain mixture B; the curing agent used is DDM (1 g), which is added to 5 mL of n-hexane to obtain mixture C; the specific steps are as follows:

[0156] S1. Add 5.6g PVP to a centrifuge tube, add 20mL ethanol and 25mL water to obtain mixture A; add 4g epoxy resin E51 to a centrifuge tube, add 8mL ethanol and 12mL water to mix, heat to 50℃ to obtain mixture B; add 1g curing agent DDM to a centrifuge tube, add 5mL n-hexane to dissolve DDM to obtain mixture C;

[0157] S2. Add mixture A to a three-necked flask, turn on mechanical stirring at 500 rpm, heat to 90°C in a water bath, then add mixtures B and C, and add 0.2 g of catalyst DBU. React for 6 hours, allow to cool naturally, centrifuge, then wash with ethanol, centrifuge three times, and dry to obtain a product with amino and hydroxyl groups on the surface, as shown in the attached... Figure 5 Hollow epoxy microspheres are shown.

[0158] In this embodiment, the average particle size of the microspheres was analyzed by laser particle size analyzer to be 753.4 μm, and the glass transition temperature was measured by DSC to be 158.8 °C.

[0159] As in Example 7, when preparing cement stone, 6 parts of microspheres were added. The specific steps are as follows:

[0160] Add 1.8g of the obtained microspheres to 30g of G-grade cement ash, add 13mL of water, shake and homogenize for 10min to obtain cement slurry; pour 5 parallel samples into pre-prepared molds, place them in a hydrothermal autoclave, cure in a 95℃ oven for 1 day, and then cure in a 95℃ constant temperature water for 6 days to obtain 5 parallel cement stone blocks.

[0161] The uniaxial compressive and three-point bending mechanical properties of cement were determined according to GB / T 19139–2012. Five samples were tested each time, and the average value was taken. Cement without added particles was used as a blank sample. The test results are shown in Table 2.

[0162] As shown in Table 2, compared with the blank sample without microspheres, the cement stone with added microspheres has increased compressive strength by 24%, flexural strength by 45%, ultimate strain by 160%, and toughness modulus by 57%.

[0163] Example 11

[0164] As in Example 1, except that in the microsphere preparation process, the surfactant used was PVP (5.6g), the stabilizer was SiO2 nanoparticles (0.06g), and 25mL of water was added to obtain mixture A; E51 was mixed with 8mL of ethanol and 12mL of water, and heated to 50°C to obtain mixture B; the curing agent used was DDM (1g), and 5mL of n-hexane was added; the specific preparation is as follows:

[0165] S1. Add 5.6g PVP and 0.06g stabilizer SiO2 nanoparticles (with epoxy and hydroxyl groups on the surface, 20nm) to a centrifuge tube, add 25mL of water to obtain mixture A; add 4g epoxy resin E51 to a centrifuge tube, add 8mL of ethanol and 12mL of water, mix, and heat to 50℃ to obtain mixture B; add 1g curing agent DDM to a centrifuge tube, add 5mL of n-hexane to dissolve DDM to obtain mixture C;

[0166] S2. Add mixture A to a three-necked flask, turn on mechanical stirring at 500 rpm, heat to 90°C in a water bath, then add mixtures B and C, and add 0.2 g of catalyst DBU. React for 6 hours, allow to cool naturally, centrifuge, then wash with ethanol, centrifuge three times, and dry to obtain a product with amino and hydroxyl groups on the surface, as shown in the attached... Figure 6 The image shows raspberry-shaped hollow epoxy microspheres.

[0167] In this embodiment, the average particle size of the microspheres was analyzed by laser particle size analyzer to be 537.5 μm, and the glass transition temperature was measured by DSC to be 154.2 °C.

[0168] As in Example 7, when preparing cement stone, 6 parts of microspheres were added. The specific steps are as follows:

[0169] Add 1.8g of the obtained microspheres to 30g of G-grade cement ash, add 13mL of water, shake and homogenize for 10min to obtain cement slurry; pour 5 parallel samples into pre-prepared molds, place them in a hydrothermal autoclave, cure in a 95℃ oven for 1 day, and then cure in a 95℃ constant temperature water for 6 days to obtain 5 parallel cement stone blocks.

[0170] The uniaxial compressive and three-point bending mechanical properties of cement were determined according to GB / T 19139–2012. Five samples were tested each time, and the average value was taken. Cement without added particles was used as a blank sample. The test results are shown in Table 2.

[0171] As shown in Table 2, compared with the blank sample without microspheres, the cement stone with added microspheres showed an increase of 26% in compressive strength, 43% in flexural strength, 193% in ultimate strain, and 72% in toughness modulus.

[0172] Table 1 Mechanical properties of different epoxy resin samples

[0173]

[0174]

[0175] Table 2 Mechanical properties of different cement stone samples

[0176]

[0177] As can be seen from the above embodiments, when epoxy resin microspheres obtained by the present invention are used to toughen epoxy resin and cement, their toughness and strength can be improved simultaneously. This may be because the present invention uses dispersion, emulsion and Pickering emulsion polymerization methods to prepare epoxy resin microspheres, without using toughening monomers, and uses monomers containing 2-4 epoxy groups and curing agents such as aromatic amines and aliphatic amines to obtain epoxy microspheres with high crosslinking degree (high Tg, 124-168℃, high strength, and certain toughness), functional groups on the surface, and porous, hollow, multi-protruding raspberry-like or semi-hollow snowman-like structures. When used for toughening epoxy and cement, the high cross-linking and high strength of microspheres ensure the strength of the epoxy. Surface functional groups can be firmly bonded to the substrate through chemical reactions, while the surface pores and protrusions create a mechanical interlock between the microspheres and the substrate. All of these enhance the interaction between the microspheres and the substrate. Under impact, the microspheres' inherent toughness and the generation of cracks within them absorb the impact energy. Simultaneously, they can induce numerous interfacial crazes and create pinning effects to prevent stress transmission, thereby improving both the toughness and strength of the epoxy. When using SiO2 nanoparticles and nanosheets to prepare microspheres, the hard SiO2 nanoparticles and sheets on the microsphere surface act as a hard phase, improving the strength of the composite material, while also generating cavitation to enhance toughness.

[0178] The present invention has been described in detail above. Those skilled in the art will recognize that the invention can be practiced in a wide range of ways with equivalent parameters, concentrations, and conditions without departing from its spirit and scope. While specific embodiments have been provided, it should be understood that further modifications can be made to the invention. In summary, according to the principles of the invention, this application is intended to include any changes, uses, or improvements to the invention, including modifications made using conventional techniques known in the art that depart from the scope disclosed herein.

Claims

1. A method for preparing multi-structured functional epoxy resin microspheres, comprising the following steps: Mixture A, mixture B, and mixture C are reacted under the action of a catalyst to obtain the multi-structured functional epoxy resin microspheres; The multi-structured functional epoxy resin microspheres include porous, hollow, raspberry-shaped, or semi-hollow snowman-shaped multi-structured epoxy resin microspheres. The glass transition temperature (Tg) of the multi-structured functional epoxy resin microspheres is 124–168 °C. The surface of the multi-structured functional epoxy resin microspheres contains one or two of amino, hydroxyl and epoxy groups, but not simultaneously amino and epoxy groups. The particle size of the multi-structured functional epoxy resin microspheres is 7.3–1116 μm; The mixture A is prepared by dispersing or dissolving a surfactant in solvent A, or by dispersing or dissolving a surfactant and a stabilizer in solvent A; The stabilizer is SiO2 nanoparticles or nanosheets with amino, epoxy, or hydroxyl groups on their surface. The mixture B is prepared by heating a mixture of epoxy resin and solvent B. The epoxy resin is selected from at least one of diepoxy monomers, triepoxy monomers, and tetraepoxy monomers; Based on 100 parts by weight of the epoxy resin, the triepoxy monomer or the tetraepoxy monomer has a mass ratio of 0 to 10 parts. The diepoxy monomer is bisphenol A diglycidyl ether E51 or E44; The triepoxy monomer is trimethylolpropane triglycidyl ether; The tetracyclic epoxy monomer is 4,4-diaminodiphenylmethane tetraglycidylamine; The solvent B is organic solvent b, or organic solvent b and water; The mixture C is prepared by dissolving a curing agent in solvent C; The curing agent is a polyamine curing agent, selected from one or more of ethyleneamine, polyetheramine, alicyclic amine, aromatic amine and curing agents containing disulfide bonds; Based on 100 parts by weight of the epoxy resin, the curing agent comprises 15 to 35 parts by weight. The solvent C is an organic solvent c, or an organic solvent c and water.

2. The method for preparing multi-structured functional epoxy resin microspheres according to claim 1, characterized in that: The surfactant is a nonionic surfactant, including one of polyvinylpyrrolidone, polyvinyl alcohol, and benzyl benzoate; When only a surfactant is added to the mixture A, the surfactant is 35 to 140 parts by mass, based on 100 parts by mass of the epoxy resin. When a surfactant and a stabilizer are added to the mixture A, the surfactant and the stabilizer are 35 to 140 parts by mass, and the stabilizer is 0.08 to 1.6 parts by mass, based on 100 parts by mass of the epoxy resin.

3. The method for preparing multi-structured functional epoxy resin microspheres according to any one of claims 1-2, characterized in that: The ethyleneamine is triethylenetetramine; The polyetheramine is polypropylene glycol di(2-aminopropyl) ether; The alicyclic amine is isophorone diamine; The aromatic amine is 4,4'-diaminodiphenylmethane or diethyltoluenediamine; The curing agent containing disulfide bonds is 4,4'-dithiodiphenylamine.

4. The method for preparing multi-structured functional epoxy resin microspheres according to any one of claims 1-2, characterized in that: Solvent A is organic solvent a and / or water; The organic solvent a, the organic solvent b, and the organic solvent c are organic alcohols, ketones, or alkanes; In solvent A, based on 100 parts by mass of epoxy resin, the organic solvent a has a mass of 0 to 493 parts by mass, and the water has a mass of 0 to 625 parts by mass, but the two are not both 0 at the same time; In solvent B, based on 100 parts by mass of the epoxy resin, the organic solvent b comprises 78 to 493 parts by mass, and the water comprises 0 to 625 parts by mass. In solvent C, based on 100 parts by mass of the epoxy resin, the organic solvent C comprises 78 to 493 parts by mass, and the water comprises 0 to 625 parts by mass.

5. The method for preparing multi-structured functional epoxy resin microspheres according to claim 4, characterized in that: The organic alcohol is ethanol.

6. The method for preparing multi-structured functional epoxy resin microspheres according to claim 4, characterized in that: The ketone is acetone.

7. The method for preparing multi-structured functional epoxy resin microspheres according to claim 4, characterized in that: The alkane in question is n-hexane.

8. The method for preparing multi-structured functional epoxy resin microspheres according to any one of claims 1-2, characterized in that: The catalyst is a tertiary amine catalyst, including one of 1,8-diazabicycloundec-7-ene, benzyl dimethylamine, and 2,4,6-tris(dimethylaminomethyl)phenol; Based on 100 parts by mass of the epoxy resin, the amount of the catalyst is 1 to 5 parts.

9. The method for preparing multi-structured functional epoxy resin microspheres according to any one of claims 1-2, characterized in that: The reaction is carried out under stirring conditions at a stirring speed of 300–500 rpm; The reaction was carried out at a temperature of 60–90 °C for 4–6 h. The preparation process further includes the following steps after the reaction is complete: centrifuging the reaction solution to collect the solid product, then washing with ethanol, centrifuging again, and drying.

10. The multi-structured functional epoxy resin microspheres obtained by the preparation method according to any one of claims 1-9.

11. The application of the multi-structured functional epoxy resin microspheres according to claim 10 in the simultaneous toughening and reinforcement of epoxy resin or cement.

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