Shear thickening material and preparation method thereof

Abstract

The invention discloses a shear thickening material and a preparation method thereof, and relates to the technical field of material preparation. The method comprises the following steps: mixing mesoporous microspheres and a dispersion medium to obtain a shear thickening suspension; mixing liquid paraffin, a first surfactant and the shear thickening suspension to obtain a water-in-oil emulsion; mixing a sodium alginate solution, a second surfactant and the self-crosslinking elastomer emulsion to obtain a sodium alginate composite solution; mixing the water-in-oil emulsion with the sodium alginate composite liquid to obtain a multiple emulsion; and mixing a calcium ion solution with the multiple emulsion, so that calcium ions in the calcium ion solution and the sodium carboxylate of the multiple emulsion are subjected to a cross-linking reaction to form a vesicle structure, and then the shear thickening material with the vesicle structure is prepared. The invention aims to solve the problems of relatively poor stability, relatively low strength and relatively low safety of a shear thickening material prepared by a related technology.

Description

Technical Field

[0001] The invention relates to the technical field of material preparation, and in particular to a preparation method of a shear thickening material and the shear thickening material. Background Art

[0002] Shear thickening fluid (STF) is a non-Newtonian fluid that has good fluidity at room temperature, and its viscosity increases sharply when subjected to a certain external force, and returns to its initial state after the external force is removed. Shear thickening fluid is generally a high-concentration suspension composed of a solid particle dispersion phase and a liquid dispersion medium. The impact response behavior of shear thickening fluid can absorb a large amount of energy, making it play an important role in viscoelastic dampers and flexible safety protection, so it has great practical value.

[0003] At present, shear thickening fluid is often compounded with other materials or filled into other material cavities to prepare buffer materials in practical applications. However, since shear thickening fluid is a high-concentration suspension, its stability is generally poor. In addition, due to its high viscosity, it is not easy to fill the shear thickening fluid into other material cavities or it is easy to leak the shear thickening fluid, resulting in poor stability, low strength and safety of the prepared material, and poor overall use effect. Summary of the invention

[0004] The invention provides a preparation method of a shear thickening material and the shear thickening material, aiming to solve the problems of poor stability, low strength and low safety of the shear thickening material prepared by the related technology.

[0005] In a first aspect, the present invention provides a method for preparing a shear thickening material, the method comprising:

[0006] The mesoporous microspheres and the dispersion medium are mixed to obtain a shear thickening suspension;

[0007] mixing liquid paraffin, a first surfactant and the shear thickening suspension to obtain a water-in-oil emulsion;

[0008] mixing a sodium alginate solution, a second surfactant and a self-crosslinking elastomer latex to obtain a sodium alginate composite liquid;

[0009] Mixing the water-in-oil emulsion with the sodium alginate composite liquid to obtain a multiple emulsion;

[0010] The calcium ion solution is mixed with the multiple emulsion, so that the calcium ions in the calcium ion solution and the sodium carboxylate in the multiple emulsion undergo a cross-linking reaction to form a vesicle structure, thereby preparing a shear thickening material having the vesicle structure.

[0011] In a second aspect, the present invention provides a shear thickening material, wherein the shear thickening material is prepared by using the above-mentioned method for preparing the shear thickening material.

[0012] The present application provides a shear thickening material and a preparation method thereof, wherein a shear thickening suspension is obtained by mixing mesoporous microspheres and a dispersion medium; liquid paraffin, a first surfactant and a shear thickening suspension are mixed to obtain an oil-in-water emulsion; a sodium alginate solution, a second surfactant and a self-crosslinking elastomer emulsion are mixed to obtain a sodium alginate composite liquid; the oil-in-water emulsion and the sodium alginate composite liquid are mixed to obtain a multiple emulsion; a calcium ion solution is mixed with the multiple emulsion so that the calcium ions in the calcium ion solution react with the sodium carboxylate of the multiple emulsion to form a vesicle structure, thereby preparing a shear thickening material with a vesicle structure. Since mesoporous microspheres with a density similar to that of the dispersion medium are used to prepare the shear thickening liquid, and the prepared shear thickening material has a vesicle structure, the stability of the shear thickening material is greatly improved, and at the same time, a self-crosslinking elastomer emulsion is introduced in the preparation process, so that the strength of the vesicle structure can be enhanced, so as to further improve the strength and safety of the shear thickening material, so that the prepared shear thickening material plays an important role in the field of safety protection, especially in flexible safety protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying any creative work.

[0014] Figure 1 A schematic flow chart of the steps of a method for preparing a shear thickening material provided in an embodiment of the present application;

[0015] Figure 2 A schematic diagram of shear thickening performance of a shear thickening suspension provided in an embodiment of the present application;

[0016] Figure 3 A schematic diagram of the storage stability of a shear thickening suspension provided in an embodiment of the present application;

[0017] Figure 4 A schematic diagram of the structure of a shear thickening material with a vesicle structure provided in an embodiment of the present application;

[0018] Figure 5 An electron microscopic diagram of a shear thickening material with a vesicle structure provided in an embodiment of the present application;

[0019] Figure 6A schematic diagram of a stress-strain curve of a shear thickening material with a vesicle structure provided in an embodiment of the present application. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] It should be understood that when used in this specification and the appended claims, the terms "include" and "comprises" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0022] It should also be understood that the terms used in this specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the specification of the present invention and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0023] It should be further understood that the term "and / or" used in the present description and the appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0024] In conjunction with the accompanying drawings, some embodiments of the present application are described in detail below. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0025] In order to solve the technical problems existing in the background technology, the present application provides a shear thickening material and a preparation method thereof. By preparing a shear thickening material with a vesicle structure on the basis of a mesoporous microsphere shear thickening liquid with a density similar to that of a dispersion medium, the stability of the shear thickening material can be greatly improved. At the same time, a self-cross-linking elastomer emulsion is introduced in the preparation process, thereby enhancing the strength of the vesicle structure, thereby further improving the strength and safety of the shear thickening material, so that the prepared shear thickening material plays an important role in the field of safety protection, especially in flexible safety protection.

[0026] See also Figure 1 , Figure 1The present invention provides a schematic flow chart of a method for preparing a shear thickening material. The method for preparing a shear thickening material can improve the stability, strength and safety of the shear thickening material, so that the prepared shear thickening material plays an important role in the field of safety protection, especially in flexible safety protection.

[0027] like Figure 1 As shown, the method for preparing the shear thickening material includes: steps S101 to S105.

[0028] S101, mixing the mesoporous microspheres and the dispersion medium to obtain a shear thickening suspension.

[0029] Mesoporous microspheres refer to microspheres with 2-50nm diameter mesopores inside, which give the mesoporous microspheres and the dispersion medium similar density. The dispersion medium is a liquid with good fluidity and stability. Shear thickening suspension is a non-Newtonian fluid that has good fluidity at room temperature, and its viscosity increases sharply when subjected to a certain external force, and returns to its initial state after the external force is removed.

[0030] In some embodiments, mesoporous microspheres, a dispersion medium, and an organic solvent are added to a ball mill for ball milling; the suspension after ball milling is dried and vacuum degassed to obtain a shear thickening suspension. Thus, a shear thickening suspension with excellent shear thickening performance, high stability, and good storage can be obtained.

[0031] The organic solvent may be a diluent such as anhydrous ethanol, which is used to dilute the mesoporous microspheres and the dispersion medium to promote the dispersion of the mesoporous microspheres in the dispersion medium.

[0032] For example, the mesoporous microspheres may be one or more of mesoporous silica microspheres, mesoporous polystyrene microspheres, and polymethyl methacrylate microspheres.

[0033] Among them, mesoporous silica microspheres are microspheres with mesopores of 2-50nm in diameter inside the microspheres, and the diameter of the microspheres is 1 micron. Mesoporous polystyrene microspheres have a particle size of 3 microns.

[0034] For example, the dispersion medium may be polyether or polyester polyols such as PEG200, PEG400 and PEG600.

[0035] In some embodiments, the density difference between the mesoporous microspheres and the dispersion medium is less than or equal to 0.2 g / cm 3 In this way, the mesoporous microspheres can be dispersed uniformly in the dispersion medium, and the mesoporous microspheres can be stably dispersed in the dispersion medium without sedimentation, thereby producing a shear thickening suspension with excellent shear thickening performance, high stability and good storage.

[0036] For example, if PEG200 is used as the dispersion medium, the density of PEG200 is 1.127 g / cm at a temperature of 25°C. 3 , the density of mesoporous microspheres needs to be controlled at 1.127±0.2g / cm 3 In the range of 1.127±0.2g / cm 3 The materials in the range are used as mesoporous microspheres.

[0037] For example, mesoporous silica microspheres with a density similar to that of the dispersion medium and the dispersion medium PEG200 can be placed in a ball mill in a certain proportion, and a small amount of anhydrous ethanol is added to dilute the mixture and ball milled for 24 hours. The ball-milled suspension is placed in a 70°C oven to dry for 24 hours and vacuum degassed in a vacuum oven for 15 minutes to obtain a shear thickening suspension with high stability.

[0038] See also Figure 2 , Figure 2 A schematic diagram of the shear thickening performance of a shear thickening suspension provided in an embodiment of the present application.

[0039] like Figure 2 As shown, Figure 2 The shear thickening properties of the shear thickening suspension prepared using mesoporous silica microspheres at different shear rates are shown. It can be seen that the shear thickening suspension exhibits good shear thickening properties when the shear rates are 20 rad / s, 40 rad / s, 60 rad / s, 80 rad / s and 100 rad / s.

[0040] See also Figure 3 , Figure 3 A schematic diagram of the storage stability of a shear thickening suspension provided in an embodiment of the present application.

[0041] like Figure 3 As shown, Figure 3 The shear thickening properties of the shear thickening suspension prepared using mesoporous silica microspheres at different times are shown. It can be seen that the shear thickening suspension exhibits good shear thickening properties both when the shear thickening suspension is prepared and after being stored for 7 days.

[0042] S102, mixing liquid paraffin, a first surfactant and a shear thickening suspension to obtain a water-in-oil emulsion.

[0043] Wherein, liquid paraffin is a liquid hydrocarbon mixture obtained from the petroleum refining process, and its main components include saturated cycloalkanes and chain alkanes, which have good lubrication. The first surfactant can be a hydrophobic surfactant. The water-in-oil emulsion is formed by mixing oil, water and an emulsifier. The form of the system is that water is dispersed in the oil in the form of small droplets, the water phase is the internal phase or dispersed phase, and the oil is the external phase or dispersion medium. In the embodiment of the present application, the water-in-oil emulsion is formed by mixing liquid paraffin, the first surfactant and a shear thickening suspension.

[0044] Specifically, the hydrophile-lipophile balance (HLB value) of the first surfactant is less than or equal to 6, such as Span 80 and Span 60, etc. Thus, the liquid paraffin can be evenly distributed in the organic system.

[0045] In some embodiments, a first surfactant is added to liquid paraffin and stirred evenly to obtain a first mixed solution, wherein the mass of the first surfactant is 30% of the mass of the liquid paraffin; a shear thickening suspension is added to the first mixed solution and stirred evenly to obtain an oil-in-water emulsion.

[0046] Wherein, the first mixed solution is a mixed solution of the first surfactant and liquid paraffin.

[0047] Exemplarily, the first surfactant may be added in an amount of 20 wt% to 40 wt% of the liquid paraffin. Preferably, the first surfactant may be added in an amount of 30 wt% of the liquid paraffin, thereby achieving a better uniform distribution of the liquid paraffin in the organic system.

[0048] For example, 3 g of the hydrophobic surfactant Span 80 can be added to 10 g of liquid paraffin (LP) and stirred evenly, and then 3 g of the shear thickening suspension is slowly dropped into it, and magnetic stirring is performed at a speed of 1000 rpm for 1 hour to obtain a water-in-oil emulsion (W / O).

[0049] S103, mixing the sodium alginate solution, the second surfactant and the self-crosslinking elastomer emulsion to obtain a sodium alginate composite solution.

[0050] Wherein, sodium alginate solution is a solution obtained by sodium alginate, which is used to provide sodium carboxylate ions for subsequent cross-linking reactions. The second surfactant can be a hydrophobic surfactant. The self-crosslinking elastomer emulsion can be a high-strength elastomer network obtained by self-crosslinking. Elastomer is a material that can restore its original state after removing external force. It is a polymer material that deforms significantly under weak stress and can quickly return to a state close to its original state and size after stress relaxation. The self-crosslinking elastomer has excellent properties such as higher strength and hardness. The sodium alginate composite liquid is a composite liquid obtained by mixing sodium alginate solution, the second surfactant and the self-crosslinking elastomer emulsion.

[0051] Specifically, the hydrophile-lipophile balance (HLB value) of the second surfactant is greater than or equal to 8, such as Span 20, Tween 20, Tween 40, Tween 60, Tween 80, etc. This allows the sodium alginate solution to be evenly distributed in the organic system.

[0052] Specifically, the self-crosslinking elastomer emulsion can be selected from one or more of polyurethane emulsion, polyacrylic acid emulsion, silicone copolymer polyacrylate emulsion, silicone copolymer polystyrene acrylic emulsion. The above self-crosslinking elastomer emulsions can enhance the strength of the vesicle structure formed subsequently, so as to further improve the strength and safety of the shear thickening material prepared subsequently.

[0053] In some embodiments, a second surfactant is added to a sodium alginate solution and stirred evenly to obtain a second mixed solution, wherein the mass of the second surfactant is 5% of the mass of the sodium alginate solution; a self-crosslinking elastomer emulsion is added to the second mixed solution and stirred evenly to obtain a sodium alginate composite solution.

[0054] The second mixed solution is a mixed solution of a second surfactant and a sodium alginate solution.

[0055] Exemplarily, the amount of the second surfactant added can be 2wt%-10wt% of the sodium alginate solution. Preferably, the amount of the second surfactant added can be 5wt% of the liquid paraffin, thereby making the sodium alginate solution more evenly distributed in the organic system.

[0056] For example, 2.5 g of a hydrophilic surfactant Span 20 and a certain amount of polyurethane emulsion can be added to 50 g of a 10 mg / ml sodium alginate (SA) solution, and the mixture is stirred thoroughly to obtain a sodium alginate composite solution.

[0057] S104, mixing the water-in-oil emulsion with the sodium alginate composite liquid to obtain a multiple emulsion.

[0058] Among them, multiple emulsions are multi-layer emulsions formed by dispersing an emulsion in another continuous phase. This emulsion usually has a highly dispersed multiphase system with different particle sizes.

[0059] In the embodiment of the present application, the type of multiple emulsion is W / O / W. The multiple emulsion provided by the present application is formed by a water-in-oil emulsion (W / O) as the inner phase, which is then suspended in an aqueous phase. The inner aqueous phase W1 and the outer aqueous phase W2 are easily miscible because they have the same polarity. Due to the special structure of the multiple emulsion, after the active ingredient is added to the inner aqueous phase, the active ingredient will not leak out during the preparation process of the vesicle shear thickening material.

[0060] For example, a water-in-oil (W / O) emulsion can be slowly dropped into a sodium alginate composite solution and magnetically stirred at 150 rpm for 1 hour to obtain a multiple emulsion, ie, a W / O / W emulsion.

[0061] S105, mixing the calcium ion solution with the multiple emulsion, so that the calcium ions in the calcium ion solution and the sodium carboxylate in the multiple emulsion undergo a cross-linking reaction to form a vesicle structure, thereby preparing a shear thickening material having a vesicle structure.

[0062] The vesicle structure can be an ordered assembly of molecules with a closed double network. The shear thickening material provided in the embodiment of the present application has a high-strength vesicle structure, thereby improving the strength and safety of the shear thickening material, and enabling the prepared shear thickening material to play an important role in the field of safety protection, especially flexible safety protection.

[0063] For example, the calcium ion solution may be a solution containing calcium ions such as calcium chloride and calcium nitrate, which is used to provide calcium ions for the cross-linking reaction.

[0064] like Figure 4 As shown, in some embodiments, the multiple emulsion is sucked into a syringe, and the multiple emulsion is dropped into the calcium ion solution using the syringe to mix the calcium ion solution with the multiple emulsion, and the injection rate of the syringe is 0.5 mL / min.

[0065] Exemplarily, the injection rate of the syringe may be 0.1 mL / min-1 mL / min. Preferably, the injection rate of the syringe may be 0.5 mL / min, thereby allowing the multiple emulsion to be better mixed with the calcium ion solution and undergo a cross-linking reaction to form a vesicle structure.

[0066] Exemplarily, the multiple emulsion can be sucked into a syringe, and the syringe pump is fixed to drop the multiple emulsion into a 10 mg / ml calcium chloride solution at a rate of 0.5 mL / min to form spherical droplets. The calcium ions in the calcium chloride solution react with the sodium carboxylate ions in the sodium alginate complex solution to form calcium alginate, that is, to form a vesicle structure.

[0067] In some embodiments, a calcium ion solution is mixed with a multiple emulsion so that the calcium ions in the calcium ion solution undergo a cross-linking reaction with the sodium carboxylate in the multiple emulsion to form a vesicle structure, and then the vesicle structure is washed and dried so that the self-cross-linking elastomer in the vesicle structure undergoes a self-cross-linking reaction with the vesicle wall material of the vesicle structure at a drying temperature to form a vesicle structure having a dual elastic cross-linking network.

[0068] Specifically, since the drying temperature is generally high, during the drying process, the drying temperature reaches the reaction temperature (generally greater than 50°C) at which the self-crosslinking elastomer and the vesicle wall material undergo a crosslinking reaction. Therefore, during the drying process, the self-crosslinking elastomer in the vesicle structure will also undergo a self-crosslinking reaction with the vesicle wall material of the vesicle structure, thereby forming an elastic crosslinking network on the vesicle wall material. At the same time, since the self-crosslinking elastomer in the vesicle structure itself also has a high-strength elastic crosslinking network, the vesicle structure now has a dual elastic crosslinking network (one located in the vesicle structure, and the other located between the vesicle structure and the vesicle wall material). Therefore, the vesicle structure with a dual elastic crosslinking network can further enhance the strength of the vesicle structure, thereby improving the strength and safety of the shear thickening material.

[0069] Illustratively, the collected vesicle structure is washed multiple times with anhydrous ethanol, and the washed vesicle structure is dried in a forced air oven set at 80°C, so that the self-crosslinking elastomer in the vesicle structure undergoes a self-crosslinking reaction with the vesicle wall material of the vesicle structure at the drying temperature, thereby obtaining a vesicle structure with a dual elastic crosslinking network, that is, a shear thickening material with a vesicle structure having high strength and high stability.

[0070] The preparation method of the shear thickening material of the embodiment of the present application is described below through specific examples.

[0071] (1) Mesoporous silica microspheres with a density similar to that of the dispersion medium and the dispersion medium PEG200 are placed in a ball mill in a certain proportion, and a small amount of anhydrous ethanol is added to dilute the mixture and ball milled for 24 hours. The ball-milled suspension is placed in a 70°C oven for drying for 24 hours and vacuum degassed in a vacuum oven for 15 minutes to obtain a shear thickening suspension with high stability.

[0072] (2) 3 g of a hydrophobic surfactant Span 80 was added to 10 g of liquid paraffin (LP) and stirred evenly, and then 3 g of a shear thickening suspension was slowly dropped into the mixture, and magnetic stirring was performed at a rotation speed of 1000 rpm for 1 hour to obtain a water-in-oil emulsion (W / O).

[0073] (3) Add 2.5 g of a hydrophilic surfactant Span 20 and a certain amount of polyurethane emulsion to 50 g of a 10 mg / ml sodium alginate (SA) solution, and stir the mixture thoroughly to obtain a sodium alginate composite solution.

[0074] (4) The water-in-oil (W / O) emulsion was slowly dropped into the sodium alginate composite solution and magnetically stirred at a rotation speed of 150 rpm for 1 h to obtain a multiple emulsion, i.e., a W / O / W emulsion.

[0075] (5) The multiple emulsion is sucked into a syringe, and the syringe is fixed on a syringe pump to drop the multiple emulsion into a 10 mg / ml calcium chloride solution at a rate of 0.5 mL / min to form spherical droplets. The calcium ions in the calcium chloride solution react with the sodium carboxylate ions in the sodium alginate complex solution to form calcium alginate, that is, to form a vesicle structure.

[0076] (6) The collected vesicle structure is washed multiple times with anhydrous ethanol, and the washed vesicle structure is dried in a forced air oven set at 80° C., so that the self-crosslinking elastomer in the vesicle structure undergoes a self-crosslinking reaction with the vesicle wall material of the vesicle structure at the drying temperature, thereby obtaining a vesicle structure with a double elastic crosslinking network, that is, obtaining a shear thickening material with a vesicle structure having high strength and high stability.

[0077] See also Figure 5 , Figure 5 An electron microscopic diagram of a shear thickening material with a vesicle structure provided in an embodiment of the present application.

[0078] like Figure 5 As shown, it can be seen that the shear thickening material has a large number of vesicle structures, which improves the strength and safety of the shear thickening material, and enables the prepared shear thickening material to play an important role in the field of safety protection, especially flexible safety protection.

[0079] See also Figure 6 , Figure 6 A schematic diagram of a stress-strain curve of a shear thickening material with a vesicle structure provided in an embodiment of the present application.

[0080] like Figure 6As shown in Figures A, B, C and D in the figure, each of which shows 6 stress-strain curves, corresponding to (1) a shear thickening material prepared without adding a self-crosslinking elastomer emulsion during the preparation process, (2) a shear thickening material prepared by adding 0.1 g of a self-crosslinking elastomer emulsion during the preparation process, (3) a shear thickening material prepared by adding 0.2 g of a self-crosslinking elastomer emulsion during the preparation process, (4) a shear thickening material prepared by adding 0.3 g of a self-crosslinking elastomer emulsion during the preparation process, (5) a shear thickening material prepared by adding 0.4 g of a self-crosslinking elastomer emulsion during the preparation process, and (6) a shear thickening material prepared by adding 0.5 g of a self-crosslinking elastomer emulsion during the preparation process.

[0081] Among them, Figure B is a local enlarged view of Figure A, and Figure D is a local enlarged view of Figure C. The self-cross-linking elastomer emulsions in Figure A and Figure C are different.

[0082] Depend on Figure 6 It can be seen that the addition of self-crosslinking elastomer emulsion during the preparation process can effectively enhance the strength of the vesicle structure, thereby significantly improving the strength of the shear thickening material with vesicle structure. If 0.5g of self-crosslinking elastomer is added during the preparation process, the strain energy of the shear thickening material can be increased from 0.32Mpa to 1.0Mpa, an increase of more than 300%.

[0083] The present application provides a method for preparing a shear thickening material, wherein the shear thickening suspension is obtained by mixing mesoporous microspheres and a dispersion medium; liquid paraffin, a first surfactant and a shear thickening suspension are mixed to obtain an oil-in-water emulsion; a sodium alginate solution, a second surfactant and a self-crosslinking elastomer emulsion are mixed to obtain a sodium alginate composite liquid; the oil-in-water emulsion and the sodium alginate composite liquid are mixed to obtain a multiple emulsion; a calcium ion solution is mixed with the multiple emulsion so that the calcium ions in the calcium ion solution react with the sodium carboxylate of the multiple emulsion to form a vesicle structure, thereby preparing a shear thickening material with a vesicle structure. Since the prepared shear thickening material has a vesicle structure, the stability of the shear thickening material is greatly improved. At the same time, the self-crosslinking elastomer emulsion is introduced in the preparation process, so that the strength of the vesicle structure can be enhanced, so as to further improve the strength and safety of the shear thickening material, so that the prepared shear thickening material plays an important role in the field of safety protection, especially in flexible safety protection.

[0084] like Figure 4 As shown, an embodiment of the present application further provides a shear thickening material, which is prepared by using the preparation method of the shear thickening material provided by any of the above embodiments.

[0085] The specific method of preparing the shear thickening material can refer to the corresponding embodiment recorded in the specification of this application, and this embodiment will not be repeated here. The shear thickening material provided in the embodiment of this application has high stability, strength and safety, and can play an important role in the field of safety protection, especially flexible safety protection.

[0086] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A method for preparing a shear thickening material, characterized in that: The method comprises: The mesoporous microspheres and the dispersion medium are mixed to obtain a shear thickening suspension; mixing liquid paraffin, a first surfactant and the shear thickening suspension to obtain a water-in-oil emulsion; mixing a sodium alginate solution, a second surfactant and a self-crosslinking elastomer latex to obtain a sodium alginate composite liquid; Mixing the water-in-oil emulsion with the sodium alginate composite liquid to obtain a multiple emulsion; The calcium ion solution is mixed with the multiple emulsion, so that the calcium ions in the calcium ion solution and the sodium carboxylate in the multiple emulsion undergo a cross-linking reaction to form a vesicle structure, thereby preparing a shear thickening material having the vesicle structure.

2. The method according to claim 1, characterized in that The mesoporous microspheres and the dispersion medium are mixed to obtain a shear thickening suspension, comprising: The mesoporous microspheres, the dispersion medium and the organic solvent are added into a ball milling jar for ball milling; The suspension after ball milling is dried and vacuum degassed to obtain a shear thickening suspension.

3. The method according to claim 1, characterized in that The liquid paraffin, the first surfactant and the shear thickening suspension are mixed to obtain a water-in-oil emulsion, comprising: Adding a first surfactant to liquid paraffin and stirring evenly to obtain a first mixed solution, wherein the mass of the first surfactant is 30% of the mass of the liquid paraffin; The shear thickening suspension is added to the first mixed solution and stirred evenly to obtain a water-in-oil emulsion.

4. The method according to claim 1, characterized in that: The sodium alginate solution, the second surfactant and the self-crosslinking elastomer emulsion are mixed to obtain a sodium alginate composite solution, comprising: Adding a second surfactant to the sodium alginate solution and stirring evenly to obtain a second mixed solution, wherein the mass of the second surfactant is 5% of the mass of the sodium alginate solution; The self-crosslinking elastomer latex is added into the second mixed solution and stirred evenly to obtain a sodium alginate composite solution.

5. The method according to claim 1, characterized in that The step of mixing the calcium ion solution with the multiple emulsion comprises: The multiple emulsion was sucked into a syringe, and the multiple emulsion was dropped into a calcium ion solution using the syringe to mix the calcium ion solution with the multiple emulsion. The injection rate of the syringe was 0.5 mL / min.

6. The method according to claim 1, characterized in that After the calcium ion solution is mixed with the multiple emulsion so that the calcium ions in the calcium ion solution and the sodium carboxylate in the multiple emulsion undergo a cross-linking reaction to form a vesicle structure, the method further includes: The vesicle structure is washed and dried so that the self-crosslinking elastomer in the vesicle structure undergoes a self-crosslinking reaction with the vesicle wall material of the vesicle structure at a drying temperature to form a vesicle structure with a double elastic crosslinking network.

7. The method according to any one of claims 1 to 6, characterized in that: The self-crosslinking elastomer emulsion includes polyurethane emulsion, polyacrylic acid emulsion, silicone copolymer polyacrylate emulsion, silicone copolymer polystyrene acrylic emulsion.

8. The method according to any one of claims 1 to 6, characterized in that: The density difference between the mesoporous microspheres and the dispersion medium is less than or equal to 0.2 g / cm 3 .

9. The method according to any one of claims 1 to 6, characterized in that: The hydrophile-lipophile balance value of the first surfactant is less than or equal to 6, and the hydrophile-lipophile balance value of the second surfactant is greater than or equal to 8.

10. A shear thickening material, characterized in that: The shear thickening material is prepared by using the method for preparing a shear thickening material according to any one of claims 1 to 9.

Images