Electrochromic silica gel as well as preparation method and application thereof
By introducing specific electrochromic silicone coupling agent and inorganic filler into PET silica gel, electrochromic silicone was prepared, which solved the problem that the PET silica gel screen protector could not achieve electrochromic function, and achieved coloring after applying voltage and Electrochromic effect of fading after disconnecting the voltage.
Patent Information
- Application Number
- CN202411529787.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-30
- Publication Date
- 2024-12-17
AI Technical Summary
The lack of electrochromic silicone in the prior art has resulted in the inability to realize the electrochromic function of PET silicone screen protector.
Using vinyl silicone oil, hydrogen-containing silicone oil, hydrogen-silica addition reaction catalyst, hydrogen-silica addition reaction inhibitor, inorganic reinforcement filler, inorganic conductive filler and structure-specific electrochromic silicone coupling agent, through hydrogen-silica addition The reaction and homogeneous mixing were made to prepare an electrochromic silica gel and cured at 110~150°C to form a silica gel with electrochromic function.
The preparation of electrochromic silicone is realized, ensuring good dispersion and compatibility of inorganic reinforcement fillers and conductive fillers in silicone, and can be colored after applying voltage, faded after disconnection of voltage, and has electrochromic function, which solves the problem of The problem of electrochromic silica gel lacks in the prior art.
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Figure CN119143995A_ABST
Abstract
Description
Technical Field
[0001] The present application belongs to the technical field of electrochromic materials, and in particular relates to an electrochromic silica gel and a preparation method and application thereof. Background Art
[0002] Color-changing materials can change their optical properties according to changes in the external environment. They are mainly divided into photochromic materials, thermochromic materials, mechanochromic materials and electrochromic materials. Electrochromic materials can undergo stable and reversible changes between a colorless and transparent state and a colored state, or between two different colors under the action of an external current or electric field. The unique optical-electrical properties of electrochromic materials have broad application prospects in new display devices, information storage devices, and adjustable reflectivity automotive rearview mirrors.
[0003] Electrochromic materials are mainly divided into transition metal oxides such as WO3, organic low molecular weight compounds such as N,N′ disubstituted 4,4′ bipyridyl cationic salts (viologens), and high molecular weight polymers such as thiophene polymers. Currently, transition metal oxides and organic low molecular weight compounds are widely studied. Among organic low molecular weight compounds, viologens have broad application prospects in various fields due to their advantages such as low cost, rich colors, high contrast, and short response time. PET silicone protective film has good scratch resistance and is often used as a screen protective film to protect the screens of various electronic products. At present, some screen protective films also have the functions of anti-blue light screen and anti-peep screen. If the PET silicone screen protective film can appropriately change the color of the protective film according to changes in the external environment, it can not only protect eyesight, but also protect personal privacy.
[0004] The PET silicone screen protective film mainly includes a PET base film and a silicone film. It is difficult to achieve the electrochromic function by directly doping electrochromic materials, such as thiophene polymers, into the silicone component. It is difficult to prepare electrochromic silicone by directly doping electrochromic materials into the silicone component, and thus it is impossible to provide an electrochromic PET silicone screen protective film. Summary of the invention
[0005] In view of this, the present application provides an electrochromic silica gel and a preparation method and application thereof, which are used to solve the technical problem of the lack of electrochromic silica gel in the prior art.
[0006] In a first aspect, the present application provides an electrochromic silica gel, the raw materials of which include: vinyl silicone oil, hydrogen-containing silicone oil, a hydrosilylation reaction catalyst, a hydrosilylation reaction inhibitor, an inorganic reinforcing filler, an inorganic conductive filler and an electrochromic organosilicon coupling agent; the general structural formula of the electrochromic organosilicon coupling agent is shown in Formula I;
[0007] Formula I;
[0008] In Formula I,
[0009] R1 is selected from , ,
[0010] , , or ;
[0011] R2 is selected from alkane, alkene, , ,
[0012] , , , , or ;
[0013] R3 is selected from , or ;
[0014] In R3, R4 and R5 are H or an olefin group.
[0015] Preferably, the alkane group in R2 is selected from alkane groups having 1 to 10 carbon atoms;
[0016] The olefin groups in R2, R4 and R5 have 2 to 10 carbon atoms.
[0017] Preferably, the hydrosilylation reaction catalyst is selected from at least one of Custer catalyst, chloroplatinic acid and platinum;
[0018] The hydrosilylation reaction inhibitor is selected from at least one of ethynyl cyclohexanol, butynol, hexynol, and dodecyl ynol;
[0019] The inorganic reinforcing filler is selected from fumed silica, and the inorganic conductive filler is selected from nano silver particles.
[0020] Preferably, calculated in parts by mass, the electrochromic silica gel includes: 500-1000 parts by mass of vinyl silicone oil, 10-50 parts by mass of hydrogenated silicone oil, 0.5-2 parts by mass of hydrosilylation reaction catalyst, 0.05-0.5 parts by mass of hydrosilylation reaction inhibitor, 200-600 parts by mass of filler and 20-100 parts by mass of electrochromic silicone coupling agent.
[0021] The second aspect of the present application provides a method for preparing electrochromic silica gel, which can be used to prepare the electrochromic silica gel described in the first aspect. The preparation method includes the steps of: uniformly mixing vinyl silicone oil, hydrogen-containing silicone oil, a hydrosilylation reaction catalyst, a hydrosilylation reaction inhibitor, an inorganic reinforcing filler, an inorganic conductive filler and an electrochromic silicone coupling agent, and vacuum degassing to obtain the electrochromic silica gel.
[0022] Preferably, the preparation method of the electrochromic organosilicon coupling agent comprises the steps of: adding 4,4'-bipyridine or its derivatives and an organic solvent into a reaction container, slowly adding epoxy silane, reacting at 60-130°C for about 8-96 hours, and evaporating the solvent to obtain the electrochromic organosilicon coupling agent.
[0023] Preferably, the molar ratio of the 4,4'-bipyridine or its derivative to epoxysilane is 1:1-5.
[0024] Preferably, the 4,4'-bipyridine or its derivatives include 4,4'-bipyridine hydrochloride and / or 1-methyl-4,4'-bipyridine chloride hydrochloride.
[0025] Preferably, the organic solvent is selected from at least one of acetonitrile, dimethylformamide, dimethyl sulfoxide and ethanol;
[0026] The epoxysiloxane is selected from at least one of 3-(2,3-epoxypropyl)propyltrimethoxysilane, 3-(2,3-epoxypropyloxy)propylmethyldimethoxysilane, 3-(2,3-epoxypropyloxy)propyltriethoxysilane, 3-(2,3-epoxypropyloxy)propylmethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane and 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane.
[0027] A third aspect of the present application provides an application of electrochromic silica gel in preparing a screen protective film for electronic products.
[0028] The fourth aspect of the present application provides a method for curing electrochromic silica gel, the curing method comprising: curing the electrochromic silica gel described in the second aspect at 110-150° C. for 1-5 hours to obtain cured electrochromic silica gel.
[0029] The fifth aspect of the present application provides an electronic product screen protective film, comprising a PET base film and the cured electrochromic silica gel described in the fourth aspect.
[0030] In summary, the present application provides an electrochromic silica gel and a preparation method and application thereof. The raw materials of the electrochromic silica gel provided by the present application include vinyl silicone oil, hydrogenated silicone oil, a silylation reaction catalyst, a silylation reaction inhibitor, an inorganic reinforcing filler, an inorganic conductive filler and an electrochromic organosilicon coupling agent; the electrochromic organosilicon coupling agent in the raw materials improves the dispersibility of the inorganic reinforcing filler and the inorganic conductive filler in the silicone rubber, so that the inorganic reinforcing filler, the inorganic conductive filler and the electrochromic organosilicon coupling agent shown in Formula I and other components have good dispersibility and compatibility, and phase separation will not occur. The electrochromic silica gel can be colored after voltage is applied and can fade after voltage is disconnected, thereby realizing the electrochromic function, thereby solving the technical problem of lack of electrochromic silica gel in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS
[0031] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0032] Figure 1 This is an infrared spectrum of an electrochromic organosilicon coupling agent in an electrochromic silica gel provided in Example 1 of the present application;
[0033] Figure 2 This is an infrared spectrum of an electrochromic organosilicon coupling agent in an electrochromic silica gel provided in Example 2 of the present application;
[0034] Figure 3 This is an infrared spectrum of an electrochromic silicone coupling agent in an electrochromic silica gel provided in Example 3 of the present application. DETAILED DESCRIPTION
[0035] The present application provides an electrochromic silica gel and a preparation method and application thereof, which are used to solve the technical problem of lack of electrochromic silica gel in the prior art.
[0036] The technical solution of the present application will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.
[0037] In view of the fact that electrochromic materials such as thiophene polymers are directly doped into the silica gel component, for example, an electrochromic silica gel disclosed in CN113265146A directly doped with thiophene polymers into the silica gel component, it is difficult to achieve the electrochromic function, resulting in the current lack of electrochromic silica gel; the present application provides an electrochromic silica gel, the raw materials of the electrochromic silica gel provided by the present application include vinyl silicone oil, hydrogen-containing silicone oil, a silylation reaction catalyst, a silylation reaction inhibitor, an inorganic reinforcing filler, an inorganic conductive filler and an electrochromic organosilicon coupling agent with a general structural formula as shown in Formula I; among the raw materials, the vinyl silicone oil, the hydrogen-containing silicone oil, the silylation reaction catalyst, and the silylation reaction inhibitor are used to undergo a silylation reaction to form a silica gel matrix, while the inorganic reinforcing filler is used to improve the strength of the silica gel, and the inorganic conductive filler is used to improve the strength of the silica gel. Conductivity of the glue; and the raw materials of the electrochromic silica gel provided by the application also include an electrochromic silicone coupling agent with a general structural formula as shown in Formula I. The electrochromic silicone coupling agent shown in Formula I has good compatibility with silica gel and contains multiple siloxane structures. It can form chemical bonds with fillers such as inorganic reinforcing fillers and inorganic conductive fillers, improve the dispersibility of inorganic reinforcing fillers and inorganic conductive fillers in silicone rubber, so that the raw material components such as silica gel, inorganic reinforcing fillers, inorganic conductive fillers and electrochromic silicone coupling agent shown in Formula I in the electrochromic silica gel provided by the application have good dispersibility and compatibility, no phase separation occurs, and the electrochromic function can be realized, thereby overcoming the current defect of lack of electrochromic silica gel.
[0038] Preferably, in an electrochromic silica gel provided by the present application, the inorganic reinforcing filler is selected from fumed silica, and the inorganic conductive filler is selected from nanosilver particles; the fumed silica and nanosilver particles are white powders, which have less effect on the transparent silica gel and can better distinguish that it has undergone electrochromic change.
[0039] Correspondingly, the present application also provides a corresponding preparation method for electrochromic silica gel. The preparation method first prepares an electrochromic silicone coupling agent, then mixes the electrochromic silicone coupling agent, vinyl silicone oil, hydrogen-containing silicone oil, a hydrosilylation reaction catalyst, a hydrosilylation reaction inhibitor and a filler, and then conducts a hydrosilylation reaction to prepare the electrochromic silica gel.
[0040] Preferably, the present application also improves the raw materials in the process of preparing the electrochromic silicone coupling agent; when 1-methyl-4, 4'-bipyridyl hydrochloride is used as the raw material, a silane coupling agent can be introduced on one side of the 1-methyl-4, 4'-bipyridyl hydrochloride, so that the electrochromic silica gel provided by the present application has a longer coloring time and a longer fading time; and when 4,4'-bipyridyl hydrochloride is used as the raw material, a silane coupling agent can be introduced on both sides of the 4,4'-bipyridyl hydrochloride, so that the electrochromic silica gel provided by the present application has a higher transparency; the present application improves the raw materials in the process of preparing the electrochromic silicone coupling agent, and the electrochromic effect of the electrochromic silica gel can be adjusted.
[0041] Correspondingly, the present application also provides a method for curing electrochromic silica gel, and the curing process is: placing the electrochromic silica gel at a temperature of 110-150° C. and curing for 1-5 hours to obtain cured electrochromic silica gel.
[0042] Example 1
[0043] Embodiment 1 of the present application provides a method for preparing an electrochromic silica gel, the method comprising the steps of preparing an electrochromic organic silicon coupling agent and performing a hydrosilylation reaction.
[0044] The step of preparing the electrochromic organosilicon coupling agent comprises: adding 10g of 4, 4'-bipyridyl hydrochloride and 200mL of anhydrous acetonitrile to a reactor equipped with a thermometer and a condenser reflux tube, slowly dropping 20g of (2, 3-epoxypropyloxy)propyltrimethoxysilane, reacting at 110°C for about 64h after the dropping is completed, removing the solvent under a vacuum degree of 0.3kPa to obtain a yellow viscous liquid, namely the electrochromic organosilicon coupling agent; the schematic flow diagram thereof is shown in Formula II;
[0045] Formula II.
[0046] The steps of the hydrosilylation reaction include: sequentially adding 360g of 2000cp vinyl silicone oil, 125g of 200 specific surface area fumed silica, 75g of nano silver particles, 25g of electrochromic organosilicon coupling agent, 15g of 0.5% hydrogenated silicone oil, and 0.05g of ethynyl cyclohexanol into a kneader, kneading them uniformly at room temperature, adding 0.5g of 3000ppm Custer catalyst, stirring them uniformly, placing them in a vacuum drying oven at room temperature, and obtaining electrochromic silica gel after sufficient degassing; then curing the electrochromic silica gel at 120°C for 2 hours to obtain cured electrochromic silica gel.
[0047] Example 2
[0048] Embodiment 2 of the present application provides a method for preparing an electrochromic silica gel, the preparation method comprising the steps of preparing an electrochromic organic silicone coupling agent and a step of a hydrosilylation reaction.
[0049] The step of preparing the electrochromic organosilicon coupling agent comprises: adding 10g of 4, 4'-bipyridyl hydrochloride and 200mL of anhydrous acetonitrile to a reactor equipped with a thermometer and a condenser reflux tube, slowly dropping 20g of (2, 3-epoxypropyloxy)propyltrimethoxysilane, reacting at 110°C for about 64h after the dropping is completed, removing the solvent under a vacuum degree of 0.2kPa to obtain a yellow viscous liquid, namely the electrochromic organosilicon coupling agent; the schematic diagram of the process is shown in Formula III;
[0050] Formula III.
[0051] The steps of the hydrosilylation reaction include: sequentially adding 370g of 2000cp vinyl silicone oil, 130g of 200 specific surface area fumed silica, 85g of nano silver particles, 27.5g of electrochromic organosilicon coupling agent, 16g of 0.5% hydrogenated silicone oil, and 0.06g of ethynyl cyclohexanol into a kneader, kneading them uniformly at room temperature, adding 0.6g of 3000ppm Custer catalyst, stirring them uniformly, placing them in a vacuum drying oven at room temperature, and obtaining electrochromic silica gel after sufficient degassing; then curing the electrochromic silica gel at 130°C for 2 hours to obtain cured electrochromic silica gel.
[0052] Example 3
[0053] Example 3 of the present application provides a method for preparing an electrochromic silica gel, which comprises the steps of preparing an electrochromic organic silicone coupling agent and a step of a hydrosilylation reaction.
[0054] The step of preparing the electrochromic organic silicon coupling agent comprises: adding 20g of 1-methyl-4, 4'-bipyridyl chloride hydrochloride and 200mL of anhydrous acetonitrile to a reactor equipped with a thermometer and a condenser reflux tube, slowly dropping 20g of (2,3-epoxypropoxy)propyltrimethoxysilane, reacting at 110°C for about 72h after the dropwise addition is completed, removing the solvent under a vacuum degree of 0.15kPa to obtain a yellow viscous liquid, namely, an electrochromic organic silicon coupling agent; the schematic flow diagram thereof is shown in Formula IV;
[0055] Formula IV.
[0056] The steps of the hydrosilylation reaction include: sequentially adding 350g of 2000cp vinyl silicone oil, 130g of 200 specific surface area fumed silica, 80g of nano silver particles, 27.5g of electrochromic organosilicon coupling agent, 17.5g of 0.5% hydrogenated silicone oil, and 0.05g of ethynyl cyclohexanol into a kneader, kneading them uniformly at room temperature, adding 0.55g of 3000ppm Custer catalyst, stirring them uniformly, putting them into a vacuum drying oven at room temperature, and obtaining electrochromic silica gel after fully removing bubbles; then curing the electrochromic silica gel at 130°C for 2 hours to obtain cured electrochromic silica gel.
[0057] Example 4
[0058] Example 4 of the present application provides a method for preparing silica gel. As a comparative example of the example, the preparation method includes: a step of hydrosilylation reaction.
[0059] 360 g of 2000 cp vinyl silicone oil, 125 g of 200 specific surface area fumed silica, 75 g of nano silver particles, 27.5 g of 1,1'-dimethyl-4, 4'-bipyridyl hydrochloride, 15 g of 0.5% hydrogen-containing silicone oil, and 0.05 g of ethynyl cyclohexanol were added into a kneader and kneaded evenly at room temperature, and then 0.5 g of 3000 ppm Custer catalyst was added and stirred evenly, and then the mixture was placed in a vacuum drying oven at room temperature to fully degas, thereby obtaining silica gel; the silica gel was then cured at 130° C. for 2 hours to obtain cured electrochromic silica gel.
[0060] Experimental Example 1
[0061] In this experimental example, the molecular structure and silica gel performance of the electrochromic silica gel provided in Examples 1-3 and the silica gel provided in Example 4 as a comparison were tested.
[0062] The infrared spectrum test results in molecular structure testing are as follows Figure 1-3 shown; from Figure 1-2 It can be seen that the electrochromic organic silicon coupling agent used in the electrochromic silica gel provided in Example 1-2 is at 3265 cm -1 The absorption peak of the hydroxyl group is at 2660 cm -1 The absorption peak of silicon methoxy appears in the vicinity at 935 cm -1The absorption peak of quaternary ammonium group appears in the attachment, which indicates that the electrochromic silicone coupling agent used in the electrochromic silica gel provided in Example 1-2 contains hydroxyl, silylmethoxy and quaternary ammonium groups in the molecular chain, and is obtained by the reaction of 4, 4'-bipyridyl hydrochloride and (2, 3-epoxypropyloxy)propyltrimethoxysilane; at the same time, in the infrared spectrum of the electrochromic silicone coupling agent used in the electrochromic silica gel provided in Example 3, absorption peaks corresponding to hydroxyl, silylmethoxy and quaternary ammonium groups also appear, which indicates that the electrochromic silicone coupling agent used in the electrochromic silica gel provided in Example 3 is obtained by the reaction of 1-methyl-4, 4'-bipyridyl hydrochloride and (2,3-epoxypropyloxy)propyltrimethoxysilane.
[0063] The electrochromic performance test process in the silicone performance test is: use an electrochemical workstation to apply voltage to the silicone provided in Examples 1-4, and record the silicone coloring response time after the voltage is applied and the silicone fading time after the voltage is disconnected; the transparency test process in the silicone performance test is: use an ultraviolet spectrophotometer to detect the transparency of the silicone.
[0064] The electrochromic performance and transparency test results in the silicone performance test are shown in Table 1.
[0065] Table 1: Electrochromic performance and transparency test results of silica gel provided in Examples 1-4
[0066]
[0067] It can be seen from Table 1 that the silica gel provided in Example 4 as a comparison does not color when stimulated by an external voltage in the electrochemical workstation, and cannot achieve the electrochromic function; while the silica gel provided in Examples 1-3 can undergo electrochromism within 4.5s to 6.5s after the voltage is applied in the electrochemical workstation, and it takes 25.4s to 32.8s to fade after the voltage is disconnected; this shows that in the silica gel provided in Examples 1-3 of the present application, the inorganic reinforcing filler, the inorganic conductive filler and the electrochromic organosilicon coupling agent shown in Formula I and other raw material components have good dispersibility and compatibility, and phase separation does not occur, thereby achieving the electrochromic function, and the silica gel is electrochromic.
[0068] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some or all of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.
Claims
1. An electrochromic silica gel, characterized in that: The raw materials include: vinyl silicone oil, hydrogen-containing silicone oil, a hydrosilylation reaction catalyst, a hydrosilylation reaction inhibitor, an inorganic reinforcing filler, an inorganic conductive filler and an electrochromic organosilicon coupling agent; the general structural formula of the electrochromic organosilicon coupling agent is shown in Formula I; Formula I; In Formula I, R1 is selected from , , , , or ; R2 is selected from alkane, alkene, , , , ,, , , or ; R3 is selected from , or ; In R3, R4 and R5 are H or an olefin group.
2. The electrochromic silica gel according to claim 1, characterized in that: The alkane group in R2 is selected from an alkane group having 1 to 10 carbon atoms; The olefin groups in R2, R4 and R5 have 2 to 10 carbon atoms.
3. The electrochromic silica gel according to claim 1, characterized in that: The hydrosilylation reaction catalyst is selected from at least one of Custer catalyst, chloroplatinic acid and platinum; The hydrosilylation reaction inhibitor is selected from at least one of ethynyl cyclohexanol, butynol, hexynol, and dodecyl ynol; The inorganic reinforcing filler is selected from fumed silica, and the inorganic conductive filler is selected from nano silver particles.
4. The electrochromic silica gel according to claim 1, characterized in that: Calculated in parts by mass, the electrochromic silica gel includes: 500-1000 parts by mass of vinyl silicone oil, 10-50 parts by mass of hydrogenated silicone oil, 0.5-2 parts by mass of hydrosilylation reaction catalyst, 0.05-0.5 parts by mass of hydrosilylation reaction inhibitor, 200-600 parts by mass of filler and 20-100 parts by mass of electrochromic silicone coupling agent.
5. The method for preparing an electrochromic silica gel according to any one of claims 1 to 4, characterized in that: The method comprises the following steps: uniformly mixing vinyl silicone oil, hydrogen-containing silicone oil, a silylation reaction catalyst, a silylation reaction inhibitor, an inorganic reinforcing filler, an inorganic conductive filler and an electrochromic organic silicon coupling agent, and performing vacuum degassing to obtain the electrochromic silica gel.
6. The method for preparing electrochromic silica gel according to claim 5, characterized in that: The preparation method of the electrochromic organosilicon coupling agent comprises the steps of: adding 4,4'-bipyridine or its derivatives and an organic solvent into a reaction container, slowly dropping epoxy silane, reacting at 60-130°C for about 8-96 hours, and evaporating the solvent to obtain the electrochromic organosilicon coupling agent.
7. The method for preparing electrochromic silica gel according to claim 5, characterized in that: The 4,4'-bipyridine or its derivatives include 4,4'-bipyridine hydrochloride and / or 1-methyl-4,4'-bipyridine hydrochloride chloride.
8. Use of the electrochromic silica gel according to any one of claims 1 to 4 in preparing screen protective films for electronic products.
9. A curing method for electrochromic silica gel, characterized in that: The curing method comprises: curing the electrochromic silica gel according to any one of claims 1 to 4 at 110 to 150° C. for 1 to 5 hours to obtain cured electrochromic silica gel.
10. A screen protective film for electronic products, characterized in that: It comprises a PET base film and the cured electrochromic silica gel as claimed in claim 9.