Modified hollow glass bead, preparation method thereof and organic silicon addition pouring sealant

Abstract

The invention relates to the field of pouring sealant spherical materials, in particular to a modified hollow glass bead, a preparation method of the modified hollow glass bead and an organic silicon addition pouring sealant. According to the modified hollow glass bead provided by the invention, the surfactant is grafted on the silane coupling agent, so that the surface of the hollow glass bead can be tightly coated with the surfactant, the surface of the hollow glass bead is highly organized, and the dispersity and the stability of the hollow glass bead in an organic silicon addition pouring sealant are greatly improved; therefore, the situation that the hollow glass beads float upwards and cake in the organosilicone addition pouring sealant and cannot be used due to too high viscosity is avoided. After the modified hollow glass beads are added into the organic silicon addition pouring sealant, the viscosity increment is greatly reduced compared with that of the unmodified hollow glass beads, the density of the organic silicon addition pouring sealant is further reduced, and the performance of the organic silicon addition pouring sealant is improved.

Description

Technical Field

[0001] This invention relates to the field of potting compound spherical materials, specifically a modified hollow glass microsphere and its preparation method, and an organosilicon addition potting compound. Background Technology

[0002] With the rapid development of the new energy vehicle industry, the requirements for the safety, reliability, and energy density of power battery systems, as their core components, are becoming increasingly stringent. Organosilicon materials, due to their excellent high and low temperature resistance, superior electrical insulation properties, good elastic cushioning ability, and chemical inertness, are considered ideal materials for potting and protecting battery modules and PACK enclosures, providing multiple functions such as thermal conductivity, flame retardancy, moisture protection, shock absorption, and insulation protection.

[0003] To meet the enormous thermal management demands of continuous charging and discharging of automotive power batteries, a large amount of highly thermally conductive fillers (such as alumina and boron nitride) must be added to the silicone addition potting compound matrix to construct efficient heat conduction pathways. However, the density of these inorganic fillers is significantly higher than that of the silicone matrix, and their large-scale introduction will drastically increase the overall density of the potting compound, resulting in a substantial increase in the total weight of the battery pack. This contradicts the core design goal of lightweighting electric vehicles to extend their driving range.

[0004] To resolve the contradiction between "high thermal conductivity" and "lightweight," the industry currently widely uses hollow glass microspheres as functional weight-reducing fillers. Their hollow structure and low true density can effectively reduce the density of composite potting compounds to a certain extent. However, the introduction of hollow glass microspheres brings new problems. The density of hollow glass microspheres differs significantly from that of silicone addition potting compounds, causing them to easily float and clump together, increasing viscosity and affecting the normal use of the potting compound. Modifying hollow glass microspheres with simple silane coupling agents has little effect. Therefore, developing a modified hollow glass microsphere that floats without clumping and flows well in silicone addition potting compounds is of significant importance. Summary of the Invention

[0005] In view of this, the technical problem to be solved by the present invention is to provide a modified hollow glass microsphere, a method for preparing the same, and an organosilicon addition potting compound. The modified hollow glass microsphere provided by the present invention will not float and clump in the organosilicon addition potting compound and has low viscosity.

[0006] This invention provides a modified hollow glass microsphere, comprising:

[0007] Hollow glass microspheres;

[0008] A siloxane-containing surfactant coated on the surface of the hollow glass microspheres;

[0009] The siloxane-containing surfactant is obtained from a carboxyl-containing anionic surfactant and a silane coupling agent.

[0010] The hollow glass microspheres of this invention are silicate glass with a density of 0.2 g / cm³. 3 ~0.4 g / cm 3 Its D90 is 40 μm to 110 μm. The siloxane-containing surfactant of this invention is obtained from a carboxyl-containing anionic surfactant and a silane coupling agent; wherein, the carboxyl-containing anionic surfactant of this invention is selected from one or more of stearic acid, lauric acid, palmitic acid, and polyacrylic acid. The silane coupling agent of this invention is selected from one or more of γ-glycidyl etheroxypropyltrimethoxysilane (KH560) or γ-(2,3-epoxypropoxy)propyltrimethoxysilane.

[0011] The mass of the siloxane-containing surfactant relative to the hollow glass microspheres in this invention is 1% to 2%; the molar ratio of the carboxyl-containing anionic surfactant to the silane coupling agent is 1:(1 to 1.2).

[0012] The modified hollow glass microspheres provided by this invention utilize a surfactant grafted onto a silane coupling agent, allowing the anionic surfactant to tightly coat the surface of the hollow glass microspheres. This significantly improves the interfacial compatibility between the hollow glass microspheres and the silicone potting compound, thereby solving the problem of hollow glass microspheres easily floating and agglomerating in the silicone potting compound. Furthermore, it can simultaneously reduce the viscosity of the silicone potting compound and increase the amount of hollow glass microspheres that can be added.

[0013] This invention provides a method for preparing the above-mentioned modified hollow glass microspheres, comprising the following steps:

[0014] S1) Under the influence of a protective gas, a silane coupling agent, a carboxyl-containing anionic surfactant, and a tertiary amine catalyst are reacted in an organic solvent to obtain a siloxane-containing surfactant.

[0015] S2) A second reaction is carried out between a siloxane-containing surfactant and hollow glass microspheres to obtain modified hollow glass microspheres.

[0016] This invention first involves reacting a silane coupling agent, a carboxyl-containing anionic surfactant, and a tertiary amine catalyst in an organic solvent under a protective gas atmosphere to obtain a siloxane-containing surfactant. Specifically, the carboxyl-containing anionic surfactant and the silane coupling agent are dissolved in an organic solvent, and a tertiary amine catalyst is added to the system. After thorough mixing, a protective gas is introduced to remove oxygen and moisture. The solution is then heated to the reaction temperature under the protective gas atmosphere to carry out the first reaction, followed by vacuum distillation to obtain the siloxane-containing surfactant.

[0017] The protective gas described in this invention is selected from one or more of nitrogen, helium, and argon. The tertiary amine catalyst described in this invention is selected from one or more of triethylamine and triethanolamine. The organic solvent described in this invention is selected from polar aprotic organic solvents, preferably one or more of toluene, xylene, isopropanol, and N,N-dimethylformamide. The silane coupling agent and carboxyl-containing anionic surfactant described in this invention are the same as described above and will not be repeated.

[0018] The carboxyl-containing anionic surfactant of this invention contains one or more carboxyl groups (-COOH). The first reaction causes the carboxyl groups in the surfactant to react with the epoxy groups in the silane coupling agent to form ester bonds, thereby grafting the surfactant onto the silane coupling agent. The temperature of the first reaction in this invention is 60℃~90℃, and the reaction time is 6 h~10 h. Preferably, the first reaction is carried out at a rotation speed of 200 r / min~1000 r / min.

[0019] The molar ratio of the carboxyl-containing anionic surfactant and the silane coupling agent in this invention is the same as described above and will not be repeated. The mass fraction of the carboxyl-containing anionic surfactant in the organic solvent is 10% to 20%; the amount of the tertiary amine catalyst added is 5% to 10% of the mass of the carboxyl-containing anionic surfactant.

[0020] This invention obtains a siloxane-containing surfactant, then performs a second reaction with hollow glass microspheres to obtain modified hollow glass microspheres. Specifically, an alcohol solution containing the siloxane surfactant is mixed with hollow glass microspheres via spraying, followed by a second reaction to obtain modified hollow glass microspheres. In some embodiments of this invention, hollow glass microspheres are added to a high-speed disperser, while the siloxane surfactant is dispersed in an alcohol solvent and added to the high-speed disperser via spraying for mixing, followed by a second reaction. The resulting material is then dried to obtain modified hollow glass microspheres.

[0021] The preferred alcohol solvent in this invention is ethanol, and the mass amount of the alcohol solvent is 4 to 10 times the mass amount of the siloxane-containing surfactant. The amount of the siloxane-containing surfactant added to the hollow glass microspheres in this invention is 1% to 2%, such that the mass of the siloxane-containing surfactant in the modified hollow glass microspheres is 1% to 2% relative to the mass of the hollow glass microspheres.

[0022] The second reaction in this invention is carried out at a temperature of 80℃~100℃, for a time of 1 h~2 h, and at a rotation speed of 1000 r / min~5000 r / min. The drying temperature in this invention is 80℃~100℃, and the drying time is 10 h~12 h.

[0023] This invention also provides an organosilicon addition potting compound, comprising hydrogen-containing silicone oil, vinyl silicone oil, a platinum catalyst, and modified hollow glass microspheres; wherein the modified hollow glass microspheres are modified hollow glass microspheres obtained by any of the preparation methods described above. Preferably, the hydrogen content of the hydrogen-containing silicone oil is 0.35%~0.37%, and the viscosity of the hydrogen-containing silicone oil is 10 cSt~20 cSt; the vinyl content of the vinyl silicone oil is 2.0 mol%~2.5 mol%, and the viscosity of the vinyl silicone oil is 100 cSt~200 cSt.

[0024] Specifically, the organosilicon addition potting compound provided by the present invention comprises component A and component B, wherein component A comprises the aforementioned hydrogen-containing silicone oil, the aforementioned modified hollow glass microspheres, and a platinum catalyst, and component B comprises the aforementioned vinyl silicone oil and the aforementioned modified hollow glass microspheres. In component A of the present invention, the mass percentage of the modified hollow glass microspheres is 20% to 40%; the mass percentage of the platinum catalyst is 0.1% to 0.3%, preferably 0.2%. In component B of the present invention, the mass percentage of the modified hollow glass microspheres is 20% to 40%.

[0025] This invention involves uniformly mixing hydrogen-containing silicone oil, modified hollow glass microspheres, and a platinum catalyst to obtain component A, and uniformly mixing vinyl silicone oil and modified hollow glass microspheres to obtain component B. Component A and component B are then uniformly mixed to obtain the aforementioned organosilicon addition potting compound. In the organosilicon addition potting compound of this invention, the mass ratio of component A to component B is 1:(0.9~1.1), preferably 1:1.

[0026] This invention provides a modified hollow glass microsphere, its preparation method, and an organosilicon addition potting compound. The modified hollow glass microsphere provided by this invention involves grafting a surfactant onto a silane coupling agent, allowing the surfactant to tightly coat the surface of the hollow glass microspheres. This achieves a high degree of organication of the hollow glass microsphere surface, significantly improving the dispersibility and stability of the hollow glass microspheres in the organosilicon addition potting compound, thereby preventing the hollow glass microspheres from floating and agglomerating in the organosilicon addition potting compound, resulting in excessive viscosity and unusable properties. The increase in viscosity of the modified hollow glass microspheres after addition to the organosilicon addition potting compound is significantly lower than that of the unmodified hollow glass microspheres. Therefore, while ensuring that the viscosity after mixing is usable, the proportion of modified hollow glass microspheres that can be added to the same mass of organosilicon addition potting compound can be increased, further reducing the density of the organosilicon addition potting compound and improving its performance. Detailed Implementation

[0027] This invention discloses a modified hollow glass microsphere, its preparation method, and an organosilicon addition potting compound. Those skilled in the art can refer to the content of this document and appropriately modify the process parameters to achieve the desired result. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art and are considered to be included in this invention. The methods and applications of this invention have been described through preferred embodiments, and those skilled in the art can clearly modify or appropriately change and combine the methods and applications described herein without departing from the content, spirit, and scope of this invention to realize and apply the technology of this invention.

[0028] The present invention will be further described below with reference to the embodiments:

[0029] Example 1

[0030] By weight, add 100 parts toluene, 10 parts stearic acid, 8 parts γ-glycidyl ether propyltrimethoxysilane (KH560) and 0.5 parts triethylamine to a three-necked flask. Then place the three-necked flask in a water bath, stir at 200 r / min until homogeneous, then purge with nitrogen and heat to 60°C. Stir at 400 r / min for 10 hours, and then distill under reduced pressure to obtain the product—glycidyl stearate propyltrimethoxysilane.

[0031] Example 2

[0032] By weight, add 100 parts toluene, 10 parts lauric acid, 12 parts γ-glycidyl etheroxypropyltrimethoxysilane (KH560) and 0.8 parts triethanolamine to a three-necked flask. Then place the three-necked flask in a water bath, stir at 200 r / min until homogeneous, then purge with nitrogen and heat to 70°C. Stir at 600 r / min for 8 hours, and then distill under reduced pressure to obtain the product—glycidyl etheroxypropyltrimethoxysilane.

[0033] Example 3

[0034] By weight, add 100 parts toluene, 10 parts palmitic acid, 10 parts γ-glycidyl ether propyltrimethoxysilane (KH560) and 1 part triethanolamine to a three-necked flask. Then place the three-necked flask in a water bath, stir at 200 r / min until homogeneous, then purge with nitrogen and heat to 90°C. Stir at 1000 r / min for 6 hours, and then distill under reduced pressure to obtain the product—glycidyl palmitate propyltrimethoxysilane.

[0035] Example 4

[0036] The density of hollow glass microspheres is 0.39 g / cm³ by weight. 3With a D90 of 40 μm, 100 parts of hollow glass microspheres were added to the hopper of a high-speed disperser and heated to 80°C. One part of glycidyl stearate propyltrimethoxysilane prepared in Example 1 was weighed and dissolved in 4 parts of ethanol. The solution was added to the hopper through the atomizing nozzle on the high-speed disperser and stirred at 1000 r / min for 2 hours. The hollow glass microspheres were then placed in an oven and dried at 80°C for 12 hours to obtain glycidyl stearate propyltrimethoxysilane modified hollow glass microspheres.

[0037] Example 5

[0038] The density of hollow glass microspheres is 0.32 g / cm³ by weight. 3 With a D90 of 85 μm, 100 parts of hollow glass microspheres were added to the hopper of a high-speed disperser and heated to 90°C. 1.5 parts of glycidyl laurate propyltrimethoxysilane prepared in Example 2 were weighed and dissolved in 8 parts of ethanol. The solution was added to the hopper through the atomizing nozzle on the high-speed disperser and stirred at 2500 r / min for 1.5 hours. The hollow glass microspheres were then placed in an oven at 90°C and dried for 10 hours to obtain glycidyl laurate propyltrimethoxysilane modified hollow glass microspheres.

[0039] Example 6

[0040] The density of hollow glass microspheres is 0.21 g / cm³ by weight. 3 With a D90 of 110 μm, 100 parts of hollow glass microspheres were added to the hopper of a high-speed disperser and heated to 100°C. Two parts of glycidyl palmitate propyltrimethoxysilane prepared in Example 3 were weighed and dissolved in 10 parts of ethanol. The solution was added to the hopper through the atomizing nozzle on the high-speed disperser and stirred at 5000 r / min for 1.5 hours. The hollow glass microspheres were then placed in an oven at 90°C and dried for 10 hours to obtain glycidyl palmitate propyltrimethoxysilane modified hollow glass microspheres.

[0041] Example 7

[0042] Prepare component A and component B of the silicone addition potting compound according to the following formulation:

[0043] By weight, component A consists of 78.8 parts of hydrogen-containing silicone oil, 21 parts of the modified hollow glass microspheres prepared in Example 6, and 0.2 parts of platinum catalyst.

[0044] By weight, component B consists of 79 parts of vinyl silicone oil and 21 parts of the modified hollow glass microspheres prepared in Example 6.

[0045] Example 8

[0046] Prepare component A and component B of the silicone addition potting compound according to the following formulation:

[0047] By weight, component A consists of 67.8 parts of hydrogen-containing silicone oil, 32 parts of modified hollow glass microspheres prepared in Example 5, and 0.2 parts of platinum catalyst.

[0048] By weight, component B consists of 68 parts of vinyl silicone oil and 32 parts of the modified hollow glass microspheres prepared in Example 5.

[0049] Example 9

[0050] Prepare component A and component B of the silicone addition potting compound according to the following formulation:

[0051] By weight, component A consists of 60.8 parts of hydrogen-containing silicone oil, 39 parts of modified hollow glass microspheres prepared in Example 4, and 0.2 parts of platinum catalyst.

[0052] By weight, component B consists of 61 parts of vinyl silicone oil and 39 parts of the modified hollow glass microspheres prepared in Example 4.

[0053] Comparative Example 1

[0054] The A and B components of the silicone addition potting compound differ from those in Example 7 in that:

[0055] The modified hollow glass microspheres of Example 6 added to components A and B were replaced with unmodified hollow glass microspheres of the same type.

[0056] Comparative Example 2

[0057] The A and B components of the silicone addition potting compound differ from those in Example 8 in that:

[0058] The modified hollow glass microspheres of Example 5 added to components A and B were replaced with unmodified hollow glass microspheres of the same type.

[0059] Comparative Example 3

[0060] The A and B components of the silicone addition potting compound differ from those in Example 9 in that:

[0061] The modified hollow glass microspheres prepared in Example 4, which were added to components A and B, were replaced with unmodified hollow glass microspheres of the same type.

[0062] Comparative Example 4

[0063] By weight, add 100 parts toluene, 10 parts methacryloyloxyethyltrimethylammonium chloride (DMC), 10 parts γ-glycidyl etheroxypropyltrimethoxysilane (KH560), and 1 part triethanolamine to a three-necked flask. Then, place the three-necked flask in a water bath, stir at 200 r / min until homogeneous, purge with nitrogen and heat to 90°C. Stir at 1000 r / min for 6 hours, and then distill under reduced pressure to obtain the product—methacryloyloxyethyldimethyl(2-hydroxy-3-(trimethoxysilyl)propyl)ammonium chloride.

[0064] Add 100 parts of material with a density of 0.21 g / cm³ to the hopper of the high-speed disperser. 3 D90 consists of 110μm hollow glass microspheres. The mixture is heated to 100℃, and 2 parts of methacryloyloxyethyl dimethyl (2-hydroxy-3-(trimethoxysilyl)propyl)ammonium chloride are weighed and dissolved in 10 parts of ethanol. This solution is then added to the hopper through an atomizing nozzle on a high-speed disperser. After stirring at 5000 r / min for 1.5 hours, the hollow glass microspheres are placed in an oven at 90℃ and dried for 10 hours to obtain methacryloyloxyethyl dimethyl (2-hydroxy-3-(trimethoxysilyl)propyl)ammonium chloride modified hollow glass microspheres, denoted as modified hollow glass microspheres-cat.

[0065] The modified hollow glass microspheres prepared in Example 6 are designated as modified hollow glass microspheres-ani. Modified hollow glass microspheres-cat and modified hollow glass microspheres-ani are weighed in a mass ratio of 1:1 and added to a high-speed disperser and stirred at 1000 r / min for 0.5 hours to obtain modified hollow glass microspheres-cat / ani.

[0066] Prepare component A and component B of the silicone addition potting compound according to the following formulation:

[0067] By weight, component A consists of 78.8 parts of hydrogen-containing silicone oil, 21 parts of modified hollow glass microspheres-CAT / ANI, and 0.2 parts of platinum catalyst;

[0068] By weight, component B consists of 79 parts vinyl silicone oil and 21 parts modified hollow glass microspheres-cat / ani.

[0069] Comparative Example 5

[0070] The density of hollow glass microspheres is 0.21 g / cm³ by weight. 3With a D90 of 110 μm, 100 parts of hollow glass microspheres were added to the hopper of a high-speed disperser and heated to 100°C. One part of palmitic acid and one part of γ-glycidyl etheroxypropyltrimethoxysilane (KH560) were weighed and dissolved in 10 parts of ethanol. The solution was added to the hopper through the atomizing nozzle on the high-speed disperser and stirred at 5000 r / min for 1.5 hours. The hollow glass microspheres were then placed in an oven at 90°C and dried for 10 hours to obtain palmitic acid modified hollow glass microspheres.

[0071] Prepare component A and component B of the silicone addition potting compound according to the following formulation:

[0072] Component A consists of 78.8 parts of hydrogen-containing silicone oil, 21 parts of palmitic acid-modified hollow glass microspheres, and 0.2 parts of platinum catalyst;

[0073] Component B consists of 79 parts vinyl silicone oil and 21 parts palmitic acid modified hollow glass microspheres.

[0074] Performance testing

[0075] The floating of hollow glass microspheres was tested by observing the A and B components of the silicone addition potting compounds of Examples 7-9 and the comparative silicone potting compounds of Comparative Examples 1-5 after being placed at room temperature for 24 hours. The results are shown in Table 1. The viscosity of the A and B components of the silicone potting compounds of Examples 7-9 and the comparative silicone potting compounds of Comparative Examples 1-5 was tested at 23±2℃ using an HBDV-2T viscometer, according to GB / T2794-2013. The results are shown in Table 1.

[0076] Table 1

[0077]

[0078] As shown in Table 1, the silicone addition potting compounds of Examples 7-9 do not exhibit floating behavior, and their viscosities are all less than 5000 mPa·s. This indicates that the surface-modified hollow glass microspheres prepared in this invention, when used in silicone addition potting compounds, do not exhibit floating behavior, and the silicone addition potting compounds have low viscosity and good flowability during use.

[0079] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A modified hollow glass microsphere, characterized by, The method comprises the following steps: Hollow glass microspheres; A siloxane-containing surfactant coated on the surface of the hollow glass microspheres; The siloxane-containing surfactant is obtained from a carboxyl-containing anionic surfactant and a silane coupling agent.

2. The modified hollow glass microsphere according to claim 1, wherein The carboxyl-containing anionic surfactant is selected from one or more of stearic acid, lauric acid, palmitic acid and polyacrylic acid; The silane coupling agent is selected from one or more of γ-glycidoxypropyltrimethoxysilane or γ-(2,3-epoxypropoxy)propyltrimethoxysilane.

3. The modified hollow glass microsphere according to claim 1, wherein The hollow glass microspheres are silicate glass with a density of 0.2 g / cm 3 0.4 g / cm 3 and a D90 of 40 μm to 110 μm.

4. The modified hollow glass microsphere according to claim 1, wherein The mass ratio of the siloxane-containing surfactant to the hollow glass microspheres is 1% to 2%; The molar ratio of the carboxyl-containing anionic surfactant to the silane coupling agent is 1:(1-1.2).

5. A method for producing the modified hollow glass microsphere according to any one of claims 1 to 4, characterized by, The method comprises the following steps: S1) under the protection of protective gas, a silane coupling agent, a carboxyl-containing anionic surfactant and a tertiary amine catalyst are subjected to a first reaction in an organic solvent to obtain a siloxane-containing surfactant; S2) the siloxane-containing surfactant and hollow glass microspheres are subjected to a second reaction to obtain modified hollow glass microspheres.

6. The method of producing modified hollow glass microspheres according to claim 5, characterized by, In step S1), the tertiary amine catalyst is selected from one or more of triethylamine and triethanolamine; The organic solvent is selected from a polar aprotic organic solvent.

7. The method of producing modified hollow glass microspheres according to claim 5, characterized by, In step S1), the amount of the tertiary amine catalyst added is 5% to 10% of the mass of the carboxyl-containing anionic surfactant; The mass fraction of the carboxyl-containing anionic surfactant in the organic solvent is 10% to 20%.

8. The method for preparing modified hollow glass microspheres according to claim 5, characterized in that, In step S1), the temperature of the first reaction is 60°C to 90°C, and the time of the first reaction is 6 h to 10 h.

9. The method of claim 5, wherein the modified hollow glass microsphere is prepared by the steps of: preparing a glass microsphere; and coating the glass microsphere with a coating layer containing a metal oxide and a metal salt. In step S2), the temperature of the second reaction is 80°C to 100°C, the time of the second reaction is 1 h to 2 h, and the second reaction is carried out at a rotation speed of 1000 r / min to 5000 r / min.

10. Silicone addition encapsulant characterized in that, The method comprises the following steps: The modified hollow glass microspheres are the modified hollow glass microspheres of any one of claims 1-4 or the modified hollow glass microspheres obtained by the preparation method of any one of claims 5-9.

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