Shock resistance design method of silica gel membrane material for straight plate rigid electronic display screen

Abstract

The technical problem that an OLED straight plate rigid electronic display screen module structure is insufficient in impact protection effect under the external force load environment of collision, falling and extrusion is solved. The invention discloses an anti-impact design method of a silica gel membrane material for a straight plate rigid electronic display screen. The method comprises the following steps: step 1, constructing performance control parameters and target design parameters of the silica gel membrane material; 2, performing performance regulation and control design on the molecular structure of the silica gel matrix, and preparing and forming corresponding silica gel matrix slurry; step 3, carrying out physical composite cross-linked network design on the silica gel matrix by using an FIAM impact-resistant reinforcing body with a non-Newtonian fluid effect, and preparing the silica gel membrane material for the straight-panel rigid electronic display screen; and step 4, carrying out performance evaluation on the silica gel membrane material designed and prepared in the step 3 and used for the straight-panel rigid electronic display screen.

Description

Technical Field

[0001] The invention discloses an impact resistance design method for a silicone gel film material for a straight rigid electronic display screen. Background Art

[0002] As a flexible adhesive material with excellent optical, mechanical, thermal and temperature-resistant properties, silicone gel (SGA) film shows great functional advantages in the engineering application of OLED (Organic Light-Emitting Diode) straight-panel rigid electronic display devices. However, with the thinning of the structure and diversification of applications of OLED electronic display equipment, traditional silicone gel film has been difficult to meet the application requirements of efficient impact protection. Therefore, while maintaining the basic application indicators of silicone gel film such as adhesion and flexibility, continuously improving the impact protection effect of silicone gel film has become a technical problem that needs to be solved urgently.

[0003] Chinese invention patent application CN116120586A discloses a solution-type FIAM flexible intelligent impact-resistant material, including 100 parts of hydroxy silicone oil and 3-8 parts of boric acid. The above patent application also discloses a method for preparing the above material, including the following steps: weighing hydroxy silicone oil and boric acid separately for standby; preheating the hydroxy silicone oil; condensation reaction of boric acid and the hydroxy silicone oil; cross-linking reaction of boric acid and the hydroxy silicone oil to obtain a solution-type FIAM flexible intelligent impact-resistant material. The shear-hardening glue-type non-Newtonian fluid material of the siloxane system with dynamically reversible boron-oxygen (BO) cross-linked bonds disclosed in the above patent application is considered to be an ideal impact protection material with excellent flexibility, self-healing and phase change effect.

[0004] Compared with the well-known shear thickening fluid (STF), FIAM (Flexible Intelligent Anti-impact Material) shows satisfactory thermal stability (heat resistance, flame retardancy), physical stability (no sedimentation, no volatility) and morphological plasticity (weak flow). Therefore, based on the physical composite mode formed by the impact reinforcement at the microscale, FIAM has been widely used in the field of functional protective materials such as fiber, rubber and foam, which can not only maintain the basic performance of functional FIAM, but also significantly enhance the impact resistance of functional protective materials. Summary of the invention

[0005] Purpose of the invention: In view of the technical problem of insufficient impact protection effect faced by silicone gel films used in OLED electronic display devices as described in the above background technology, the present invention discloses an impact-resistant design method for silicone gel films for straight-plate rigid electronic display screens. By determining the application parameters of silicone gel films, designing molecular structures, designing composite cross-linking, and analyzing and evaluating performance, the invention aims to significantly enhance the material's impact resistance while ensuring the multifunctional application goals of silicone gel.

[0006] In order to strengthen the application technology advantages of silicone gel film materials in the impact protection of OLED electronic devices, the present invention proposes a targeted regulation design method for realizing the impact resistance of silicone gel at the molecular scale. At the same time, in view of the excellent empowering effect of FIAM on functional protective materials, the dynamic boron-oxygen cross-linking bonds unique to FIAM impact reinforcement are creatively introduced into the silicone gel molecular cross-linking network. Through the interpenetrating cross-linking network design of FIAM and silicone gel molecular chains, the impact energy absorption efficiency of silicone gel can be further highlighted, which has important engineering application value for promoting the technical upgrade of OLED straight-panel rigid electronic display devices.

[0007] Technical solution: The impact-resistant design method of silicone gel film for straight rigid electronic display screens, the steps are as follows:

[0008] Step 1: According to the actual application scenarios of silicone gel film materials in straight-panel rigid electronic display devices, performance control parameters and target design parameters of silicone gel film materials are established;

[0009] Step 2: Based on the performance control parameters determined in step 1, the molecular structure of the silicone gel matrix is ​​designed for performance regulation, and a corresponding silicone gel matrix slurry is prepared;

[0010] Step 3: Based on the target design parameters of the silicone gel film constructed in step 1, a FIAM impact reinforcement with a non-Newtonian fluid effect is used to perform a physical and chemical composite cross-linking network design on the silicone gel matrix to prepare a silicone gel film for a straight rigid electronic display screen:

[0011] Step 4: Based on the application scenario of silicone gel film materials in OLED straight-panel rigid electronic display screens, the performance of the silicone gel film materials designed and prepared in step 3 for straight-panel rigid electronic display screens is evaluated.

[0012] Furthermore, the main application scenario of the silicone gel film material in step 1 is the lower part of the OLED screen of the straight rigid electronic display screen. The silicone gel film material is intended to be used to achieve the fixed bonding of each functional layer of the OLED display module, and at the same time provide the OLED module with functional goals such as buffering energy absorption, light isolation and shock absorption, and electrostatic shielding.

[0013] Furthermore, the performance control parameter of the silicone gel film in step 1 is the dynamic cross-linking mode of the silicone gel molecular chain. The initial cross-linking density of the silicone gel molecular chain is a key factor affecting the elastic modulus:

[0014] The greater the initial cross-linking density, the higher the elastic modulus of the silicone gel.

[0015] The dynamic entanglement effect of the molecular chain is a key factor affecting the rate effect coefficient; the stronger the dynamic entanglement effect, the higher the rate effect coefficient of the silicone gel.

[0016] The force between molecular chains is the key factor affecting the damping coefficient; the greater the intermolecular force, the higher the damping coefficient of the silicone gel.

[0017] Furthermore, the target design parameters of the silicone gel film material described in step 1 include main design targets and auxiliary design targets, wherein:

[0018] The main design objectives are impact energy absorption rate, rate effect coefficient and damping coefficient;

[0019] The auxiliary design targets are elastic modulus, peel strength, shading coefficient, surface resistance and film tearing voltage.

[0020] Furthermore, the performance regulation design of the molecular structure of the silicone gel matrix in step 2 is achieved by controlling the dynamic cross-linking mode of the molecular chain of the silicone gel matrix, thereby achieving effective regulation of the elastic modulus, rate effect coefficient and damping coefficient of the silicone gel. The specific steps are as follows:

[0021] 2A. By adjusting the content of the cross-linking agent, the initial cross-linking density of the silicone gel molecular chain is controlled, thereby obtaining a silicone gel with a corresponding elastic modulus;

[0022] 2B. By adjusting the content of the tackifier, the interaction force between the silicone gel molecular chains is controlled to obtain silicone gel with a corresponding damping coefficient;

[0023] 2C. By adjusting the proportion of catalysts, the dynamic entanglement effect of the silicone gel molecular chain is controlled, thereby achieving parameter design of the rate effect coefficient;

[0024] 2D. By regulating the time and temperature of the cross-linking reaction, the cross-linking density and intermolecular force of silicone gel can be effectively controlled.

[0025] Furthermore, the silicone gel matrix slurry in step 2 is composed of the following components: methyl vinyl silicone rubber, methyl MQ silicone resin, benzoyl peroxide, xylene, a crosslinking agent, a tackifier, an inhibitor, a catalyst and carbon nanotubes.

[0026] Furthermore, the cross-linking agent is hydrogen-containing silicone oil.

[0027] Furthermore, the tackifier is one of a silane coupling agent and a titanate coupling agent.

[0028] Furthermore, the inhibitor is one of 1-ethynylcyclohexanol, 2-methyl-3-butyn-2-ol and 3,5-dimethyl-1-hexyn-3-ol.

[0029] Furthermore, the catalyst is platinum catalyst PT4000.

[0030] Furthermore, the preparation method of the silicone gel matrix slurry described in step 2 includes:

[0031] (21), dissolving a formulated amount of methyl vinyl silicone rubber and a formulated amount of methyl MQ silicone resin in a formulated amount of xylene;

[0032] (22), adding a formulated amount of inhibitor and a formulated amount of dibenzoyl peroxide, and mixing them uniformly to form a main material of a silicone gel matrix;

[0033] (23) Add a formulated amount of a cross-linking agent, a formulated amount of a tackifier, a formulated amount of a catalyst, and a formulated amount of carbon nanotubes to the main material of the silicone gel matrix obtained in step (22), and stir evenly to obtain a silicone gel matrix slurry.

[0034] The FIAM impact reinforcement in step three is an optical solution-type material with non-Newtonian fluid properties formed by introducing boron atoms into the molecular main chain of linear polydimethylsiloxane (by adding boric acid for chemical reaction). Its molecular weight in solution state is low and its molecular chain is short.

[0035] Furthermore, based on the total weight of the silicone gel matrix, the addition amount of the FIAM impact reinforcement is 5%. Based on the systematic analysis of various properties, in order to maximize the impact resistance of the silicone gel matrix without affecting its peel strength, the optimal addition ratio of the FIAM impact reinforcement is determined to be 5% of the total weight of the silicone gel matrix (without solid content).

[0036] Furthermore, the steps of designing a physical and chemical composite cross-linked network of the silicone gel matrix by using the FIAM impact reinforcement with non-Newtonian fluid effect to prepare the silicone gel film material include:

[0037] (31) Add 5 parts of FIAM impact reinforcement directly to 100 parts of silicone gel matrix slurry at room temperature;

[0038] (32), fully mixing the FIAM impact-resistant reinforcement and the silicone gel composite slurry, and then performing vacuum degassing treatment to obtain an impact-resistant composite silicone gel;

[0039] (33) According to the high-temperature film-forming process, the impact-resistant composite silicone gel is cross-linked to obtain a silicone gel film material of corresponding thickness for a straight-panel rigid electronic display screen. On the one hand, the FIAM impact-resistant reinforcement is polymerized from short-chain molecules to long-chain molecules, and on the other hand, a physical cross-linking network is formed between the FIAM molecular chain and the silicone gel molecular chain, thereby introducing dynamic boron-oxygen bonds into the physical cross-linking network content.

[0040] Furthermore, the film forming process described in step (33) includes:

[0041] (331) using a high-precision film applicator to coat the degassed impact-resistant composite silicone gel on the PET release film, with a coating thickness of 130 μm;

[0042] (332) The PET-silicone gel film was placed in a vacuum oven at 80 °C for 5 min to pre-evaporate the solvent, mainly to prevent bubbles from appearing during the curing of the silicone gel;

[0043] (333) The temperature of the vacuum oven is raised to 150 °C to perform a cross-linking reaction on the silicone gel for 8 min, thereby obtaining a silicone gel film material of a corresponding thickness facing a straight-panel rigid electronic display screen.

[0044] Furthermore, the specific steps of step four are as follows: according to the actual application conditions of silicone gel in the straight-plate rigid electronic display module, the mechanical properties, impact energy absorption, peel strength, shading performance and film tearing voltage of the silicone gel film for the straight-plate rigid electronic display are systematically evaluated.

[0045] Beneficial effects: Compared with the prior art, the technical advantages of the present invention are:

[0046] (1) The present invention clarifies the performance control parameters and target design parameters of silicone gel according to the actual application scenarios, and can achieve directional design of the impact resistance of silicone gel from the molecular structure level.

[0047] (2) The present invention introduces the unique dynamic boron-oxygen cross-linking bonds in FIAM flexible intelligent impact-resistant materials into silicone gel molecules to form a physical cross-linking network, thereby significantly enhancing the strain rate effect and damping properties of the silicone gel matrix.

[0048] (3) Based on the dynamic cross-linked network formed by the FIAM impact reinforcement and the silicone gel matrix, the composite silicone gel not only exhibits efficient impact energy absorption and cushioning properties, but also the properties such as peel strength, shading coefficient and tearing voltage fully meet the functional application requirements of silicone gel. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1The present invention is a flow chart of the impact resistance design method of the silicone gel film material for a straight rigid electronic display screen disclosed in the present invention.

[0050] Figure 2 Schematic diagram of the composite cross-linking network of SGA silicone gel matrix

[0051] Figure 3 Schematic diagram of the composite cross-linked network of FSGA composite silicone gel.

[0052] Figure 4 Schematic diagram of the elastic modulus and viscous modulus of the silicone gel film material for a straight-panel rigid electronic display screen prepared in Example 1.

[0053] Figure 5 Schematic diagram of the damping coefficient of the silicone gel film material for a straight-panel rigid electronic display screen prepared in Example 1. DETAILED DESCRIPTION

[0054] The specific embodiments of the present invention are described in detail below.

[0055] The "range" disclosed in the present invention is defined in the form of a lower limit and an upper limit, and a given range is defined by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundaries of the particular range. The range defined in this way can be inclusive or exclusive of the end values, and can be arbitrarily combined, that is, any lower limit can be combined with any upper limit to form a range. For example, if a range of 10 to 50 is listed for a specific parameter, it is understood that the range of 10 to 40 and 20 to 50 is also expected. In addition, if the minimum range values ​​1 and 2 are listed, and if the maximum range values ​​3, 4 and 5 are listed, the following ranges can all be expected: 1 to 3, 1 to 4, 1 to 5, 2 to 3, 2 to 4 and 2 to 5. In this application, unless otherwise specified, the range of values ​​"a to b" represents an abbreviation of any real number combination between a and b, where a and b are both real numbers. For example, the range of values ​​"0 to 5" means that all real numbers between "0 to 5" have been fully listed in this article, and "0 to 5" is only an abbreviation of these numerical combinations.

[0056] Unless otherwise specified, all embodiments and optional embodiments of the present application can be combined with each other to form a new technical solution.

[0057] Unless otherwise specified, all technical features and optional technical features of this application can be combined with each other to form a new technical solution.

[0058] If there is no special explanation, all steps of the present application can be performed sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), which means that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially. For example, the method may further include step (c), which means that step (c) may be added to the method in any order. For example, the method may include steps (a), (b) and (c), or may include steps (a), (c) and (b), or may include steps (c), (a) and (b), etc.

[0059] If there is no special explanation, the "include" and "comprising" mentioned in this application are open-ended or closed-ended. For example, the "include" and "comprising" may mean that other components not listed may also be included or only the listed components may be included or only the listed components may be included.

[0060] Unless otherwise specified, the reaction is carried out at room temperature and pressure.

[0061] Unless otherwise specified, all parts or percentages are by weight.

[0062] In the present invention, all substances used are known substances and can be purchased or synthesized by known methods.

[0063] In the present invention, the devices or equipment used are all conventional devices or equipment known in the art and are commercially available.

[0064] Example 1

[0065] The impact resistance design method of silicone gel film for straight rigid electronic display screen is as follows:

[0066] Step 1: According to the actual application scenarios of silicone gel film materials in OLED straight-panel rigid electronic display devices, construct performance control parameters and target design parameters that meet the application index requirements of silicone gel film materials

[0067] Through the analysis of the factors affecting the impact resistance of silicone gel, the molecular cross-linking mode is established as the performance control parameter of silicone gel film. Among them:

[0068] The greater the molecular cross-linking density of the silicone gel film, the higher the initial elastic modulus of the silicone gel, which is mainly characterized by the elastic modulus;

[0069] The stronger the molecular dynamic cross-linking effect of the silicone gel film is, the more obvious the strain rate effect of the silicone gel under impact load is, and the stronger the resistance to impact deformation is, which is mainly characterized by the rate effect coefficient;

[0070] The stronger the intermolecular force of the silicone gel film material, the more obvious the damping characteristics of the silicone gel are, and the more efficient the energy dissipation of the impact load is, which is mainly characterized by the damping coefficient.

[0071] In order to significantly enhance the impact protection efficiency of silicone gel film materials and realize the efficient application of silicone gel in OLED straight rigid electronic display devices (under OLED screens), the present invention determines the impact energy absorption rate, elastic modulus, rate effect coefficient and damping coefficient as the main target design parameters, and the peel strength, shading coefficient, surface resistance and film tearing voltage as auxiliary target design parameters. Among them:

[0072] A. Impact energy absorption rate is used to reflect the ability of silicone gel to dissipate impact loads. The higher the impact energy absorption rate, the stronger the impact protection efficiency of silicone gel. The application index must be higher than 70%.

[0073] B. Elastic modulus is used to reflect the energy stored in silicone gel when it undergoes elastic (reversible) deformation, characterizes the stiffness characteristics of silicone gel, and has an application index range of 20 to 100 kPa.

[0074] C. The rate effect coefficient is used to reflect the sensitivity of silicone gel's mechanical properties to strain rate, and can indirectly reflect the dynamic entanglement density of silicone gel molecular chains. The application index must be higher than 8.0. The higher the rate effect coefficient, the stronger the strain rate sensitivity and molecular entanglement effect of silicone gel.

[0075] D. The damping coefficient is used to reflect the internal force of silicone gel molecules, and the application index must be higher than 1.0; the higher the damping coefficient, the stronger the energy absorption and shock absorption properties of the silicone gel.

[0076] E. Peel strength is used to reflect the stability of silicone gel's fixed adhesion function. The application index at 25°C must be higher than 1500gf / inch, and the high temperature strain index at 80°C must be higher than 800gf. The higher the peel strength, the better the silicone gel's bonding performance, and the lower the probability of failure risks such as debonding.

[0077] F. The shading coefficient is used to reflect the ability of silicone gel to shield the light generated by the OLED display screen. The application index must be higher than 92%. The higher the shading coefficient, the better the silicone gel's ability to shield light.

[0078] G. Surface resistance is used to reflect the conductivity of silicone gel, and the application index must be less than 10 10 Ω; the lower the surface resistance, the better the conductivity of the surface silicone gel.

[0079] H. The tearing voltage is used to reflect the electrostatic shielding effect of silicone gel during transportation and assembly. The application index must be lower than 500V. The lower the tearing voltage, the stronger the electrostatic shielding effect of silicone gel.

[0080] Step 2: According to the performance control parameters determined in step 1, the molecular structure of the silicone gel matrix is ​​controlled and designed from the material formulation level including the crosslinking agent, tackifier, and catalyst, and the preparation process level including the crosslinking reaction time and temperature, and the corresponding silicone gel matrix slurry is prepared:

[0081] Based on the performance control parameters of the silicone gel membrane material described in step one and on the basis of the analysis of factors affecting performance, a silicone gel formulation system and ratio are established.

[0082] The silicone gel matrix slurry consisted of the following composition: 20 parts of methyl vinyl silicone rubber, 30 parts of methyl MQ silicone resin, 0.1 parts of benzoyl peroxide, 50 parts of xylene, 0.3 parts of crosslinking agent, 0.5 parts of adhesion promoter, 0.3 parts of inhibitor, 0.5 parts of catalyst and 3 parts of carbon nanotubes.

[0083] Furthermore, the cross-linking agent is hydrogen-containing silicone oil.

[0084] Furthermore, the tackifier is a silane coupling agent. In other embodiments, the tackifier is a titanate coupling agent.

[0085] Furthermore, the inhibitor is 1-ethynylcyclohexanol. In other embodiments, the inhibitor is 2-methyl-3-butyn-2-ol. In other embodiments, the inhibitor is 3,5-dimethyl-1-hexyn-3-ol.

[0086] Furthermore, the catalyst is platinum catalyst PT4000.

[0087] Preparation of silicone gel matrix slurry:

[0088] The main material including 20 parts of methyl vinyl silicone rubber and 30 parts of methyl MQ silicone resin was simultaneously dissolved in 50 parts of xylene (solvent);

[0089] Add 0.3 parts of inhibitor and 0.1 parts of dibenzoyl peroxide, and mix them evenly to form the main material of the silicone gel matrix;

[0090] 0.3 parts of a crosslinking agent, 0.5 parts of a tackifier and 0.5 parts of a catalyst were added to the main material of the silicone gel matrix to prepare a silicone gel matrix slurry.

[0091] In order to ensure the conductive property of the silicone gel, 3 parts of carbon nanotubes were added and mixed evenly to form a conductive silicone gel matrix slurry.

[0092] The performance regulation design of the molecular structure of the silicone gel matrix described in step 2 is to control the dynamic cross-linking mode of the molecular chain of the silicone gel matrix, thereby achieving effective regulation of the elastic modulus, rate effect coefficient and damping coefficient of the silicone gel. The specific steps are as follows:

[0093] 2A. To form a silicone gel with a lower elastic modulus, the cross-linking density of the silicone gel molecular chain is reduced by reducing the proportion of the cross-linking agent;

[0094] 2B. To form a silicone gel with a high damping coefficient, the proportion of the viscosity enhancer is increased to strengthen the molecular chain force of the silicone gel;

[0095] 2C. To form a silica gel that is sensitive to the strain rate effect, the proportion of the catalyst is increased to enable the silica gel molecules to quickly form more long chains during the chemical reaction;

[0096] 2D. By prolonging the cross-linking reaction time and increasing the cross-linking reaction temperature, the molecular cross-linking density and intermolecular force of silicone gel can be further enhanced.

[0097] Step 3: Based on the design parameters with impact energy absorption rate, rate effect coefficient and damping coefficient as the main targets, and the target design parameters with elastic modulus, peel strength, shading coefficient, surface resistance and film tearing voltage as auxiliary targets, the FIAM impact reinforcement with non-Newtonian fluid effect is used to design a physical and chemical composite cross-linking network for the silicone gel matrix, so as to innovatively introduce the dynamic boron-oxygen cross-linking bonds unique to FIAM into the molecular network of silicone gel, and prepare silicone gel film materials for straight-panel rigid electronic display screens:

[0098] Furthermore, the preparation method of FIAM impact reinforcement is as follows: boric acid powder and linear polydimethylsiloxane solution are used as raw materials, and the preparation method described in Chinese patent application CN116120586A is used to chemically synthesize the two types of raw materials, so as to introduce the oxygen atoms in the boric acid into the molecular main chain of the siloxane to form a boron-oxygen chemical bond. Since the electronegativity of the boron atom (2.04) is lower than that of the oxygen atom (3.44) at the electronic level, and there are missing electrons and surplus electrons on the P orbitals of the boron atom and the oxygen atom, respectively, so that the P orbital of the boron atom can form a boron-oxygen cross-linking bond in a dynamic equilibrium process of breaking and forming after obtaining the lone pair of electrons of the oxygen atom on the adjacent molecular chain.

[0099] Furthermore, the steps of designing a physical and chemical composite cross-linked network of the silicone gel matrix by using the FIAM impact reinforcement with non-Newtonian fluid effect to prepare the silicone gel film material include:

[0100] (31) With 100 parts of silicone gel matrix slurry as the main body, 5 parts of FIAM impact reinforcement are added to the silicone gel slurry at room temperature to obtain FSGA composite silicone gel. The schematic diagram of the composite cross-linking network of FSGA composite silicone gel is shown in Figure 3 As shown;

[0101] (32) after being fully mixed, the composite slurry is subjected to vacuum degassing treatment;

[0102] (33) According to the high-temperature film-forming process, the impact-resistant composite silicone gel is subjected to a cross-linking reaction to obtain a silicone gel film material of a corresponding thickness for a straight-panel rigid electronic display screen. According to the high-temperature film-forming process of silicone gel, after the xylene solvent in the composite silicone gel slurry is fully volatilized, the silicone gel film material is subjected to a cross-linking reaction for 8 minutes in a vacuum high-temperature environment of 150°C. On the one hand, the high-temperature cross-linking reaction is used to promote the further polymerization of the FIAM impact-resistant reinforcement from short-chain molecules to long-chain molecules; on the other hand, the high-temperature cross-linking reaction is used to promote the formation of a physical cross-linking network between the FIAM molecular chain and the silicone gel molecular chain, thereby introducing dynamic boron-oxygen bonds into the physical cross-linking network structure. Originating from the dynamic boron-oxygen cross-linking network formed inside the silicone gel molecules, the silicone gel film material can show mechanical properties with a low initial elastic modulus, and the molecular chain entanglement caused at high strain rates helps to further enhance the strain rate effect of the silicone gel.

[0103] Furthermore, the specific steps of the film forming process described in step (33) include:

[0104] (331) using a high-precision applicator to apply the degassed silicone gel slurry onto a PET release film with a coating thickness of 130 μm;

[0105] (332) The PET-silicone gel film was placed in a vacuum oven at 80 °C for 5 min to pre-evaporate the solvent, mainly to prevent bubbles from appearing during the curing of the silicone gel;

[0106] (333) The temperature of the vacuum oven is raised to 150 °C to perform a cross-linking reaction on the silicone gel for 8 min, thereby obtaining a silicone gel film material of a corresponding thickness facing a straight-panel rigid electronic display screen.

[0107] Step 4: Based on the application scenarios of silicone gel film materials under OLED straight-panel rigid electronic display screens, the silicone gel film materials designed and prepared in step 3 for straight-panel rigid electronic display screens are verified for multifunctional applications such as elastic modulus, rate effect coefficient, damping coefficient, impact energy absorption rate, peel strength, shading coefficient, surface resistance and film tearing voltage, among which:

[0108] ① Elastic modulus, rate effect coefficient, and damping coefficient verification: Under 1% shear strain and 25°C constant temperature environment, the silicone gel was subjected to a 0.1-100Hz sweep frequency test to obtain the frequency spectrum of the elastic modulus (i.e., storage modulus), viscous modulus (i.e., loss modulus), and damping coefficient (i.e., the ratio of viscous modulus to elastic modulus). Among them, the elastic modulus and damping coefficient both use the values ​​corresponding to a frequency of 1Hz, and the rate effect coefficient is calculated by dividing the (difference between the 100Hz high-frequency elastic modulus and the 0.1Hz low-frequency elastic modulus) by the 0.1Hz low-frequency elastic modulus.

[0109] ② Impact energy absorption rate verification:

[0110] A. Place 130μm thick silicone gel on the surface of the impact force sensor;

[0111] B. A steel ball weighing 11.2 g was vertically impacted on the silicone gel film at an impact height of 55 mm;

[0112] C. Use a force sensor with a sampling frequency of 1 MHz to synchronously record the impact force-time response of the back of the silicone gel film, and synchronously obtain the no-load impact force-time response without the protection of the silicone gel film;

[0113] D. Based on the peak impact force under no-load and film-attached impact, the impact energy absorption rate of silicone gel is calculated as 1-no-load impact force / film-attached impact force. The higher the impact energy absorption rate, the stronger the impact protection performance of silicone gel.

[0114] ③ Peel strength: Prepare the silicone gel film into a standard sample with a length of 150mm and a width of 25mm, and stick 3 / 4 of it on the surface of the copper foil and let it stand for 24 hours; fix the copper foil on the lower end fixture of the tensile testing machine, and bend the silicone gel film 180° in the opposite direction and clamp it on the upper end fixture; at a tensile speed of 300mm / min, use a force sensor to measure the peel force under the environment of 25℃ room temperature and 80℃ high temperature (keeping warm for 5min).

[0115] ④Shading coefficient: The incident light flux and transmitted light flux of the silicone gel were tested separately using a spectrophotometer, and the shading coefficient of the silicone gel was calculated as follows = 1-transmitted light flux / incident light flux.

[0116] ⑤ Surface resistance: Place the silicone gel film on an insulating pad and place the surface resistance tester on the surface of the silicone gel; adjust the voltage switch of the surface resistance tester to the required voltage position (10V), and continue to press the measurement button with a pressure of about 25N to read the surface resistance value of the silicone gel film.

[0117] ⑥ Film tearing voltage: Fix the silicone gel sample on the tear force testing machine, perform a film tearing test on the PET release film at a standard test speed and angle, and use a voltmeter to record the voltage changes during the test in real time.

[0118] Example 2

[0119] It is substantially the same as Example 1, except that:

[0120] The tackifier is a titanate coupling agent;

[0121] The inhibitor is 2-methyl-3-butyn-2-ol.

[0122] Example 3

[0123] It is substantially the same as Example 1, except that:

[0124] The tackifier is a titanate coupling agent;

[0125] The inhibitor is 3,5-dimethyl-1-hexyn-3-ol.

[0126] Performance and testing:

[0127] The SGA silicone gel matrix prepared by the technical method of the present invention is different only in that the FIAM impact reinforcement is not added. Figure 2 As shown, where:

[0128] The original SGA matrix uses 0.5 parts of a crosslinking agent (hydrogenated silicone oil), 0.35 parts of a tackifier (silane coupling agent) and 0.4 parts of a catalyst (platinum catalyst PT4000), and the crosslinking reaction temperature and time are 135° C. and 5 minutes.

[0129] The SGA regulating matrix is ​​based on the original SGA matrix, with the cross-linking agent (hydrogen-containing silicone oil) reduced to 0.3 parts, the tackifier (silane coupling agent) increased to 0.5 parts, the catalyst (platinum catalyst PT4000) increased to 0.5 parts, the cross-linking reaction temperature increased to 150°C, and the cross-linking reaction time extended to 8 minutes.

[0130] The performance parameters of the SGA silicone gel matrix and the silicone gel film material prepared above for straight-panel rigid electronic display screens are shown in the following table, and are compared with the performance of similar silicone gel products SGA-1 and SGA-2 currently available on the market.

[0131] It can be seen from the table that the SGA silicone gel matrix formed by the present invention not only maintains excellent peel strength and conductive properties, but also has significantly higher impact energy absorption rate, rate effect coefficient and damping coefficient than the existing SGA silicone gel products.

[0132] Further, such as Figure 4 and Figure 5 As shown in the table below, compared with the SGA silicone gel matrix, the impact energy absorption rate, rate effect coefficient and damping coefficient of the silicone gel film material for the straight-panel rigid electronic display screen prepared in Example 1 at 25°C are significantly improved.

[0133]

[0134]

[0135] The above describes the embodiments of the present invention in detail. However, the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of ordinary technicians in the relevant technical field without departing from the purpose of the present invention.

Claims

1. A method for designing the impact resistance of silicone gel film materials for straight rigid electronic display screens, characterized in that: Here are the steps: Step 1: According to the actual application scenarios of silicone gel film materials in straight-panel rigid electronic display devices, performance control parameters and target design parameters of silicone gel film materials are established; Step 2: Based on the performance control parameters determined in step 1, the molecular structure of the silicone gel matrix is ​​designed for performance regulation, and a corresponding silicone gel matrix slurry is prepared; Step 3: Based on the target design parameters of the silicone gel film constructed in step 1, a FIAM impact reinforcement with a non-Newtonian fluid effect is used to perform a physical and chemical composite cross-linking network design on the silicone gel matrix to prepare a silicone gel film for a straight rigid electronic display screen: Step 4: Based on the application scenario of silicone gel film materials in OLED straight-panel rigid electronic display screens, the performance of the silicone gel film materials designed and prepared in step 3 for straight-panel rigid electronic display screens is evaluated.

2. The impact resistance design method of silicone gel film material for straight rigid electronic display screen according to claim 1, characterized in that: The main application scenario of the silicone gel film material described in step 1 is the lower part of the OLED screen of the straight rigid electronic display screen; The performance control parameter of the silicone gel film material in step 1 is the dynamic cross-linking mode of the silicone gel molecular chain.

3. The impact resistance design method of silicone gel film material for straight rigid electronic display screen according to claim 1, characterized in that: The target design parameters of the silicone gel membrane described in step 1 include main design targets and auxiliary design targets, among which: The main design objectives are impact energy absorption rate, rate effect coefficient and damping coefficient; The auxiliary design targets are elastic modulus, peel strength, shading coefficient, surface resistance and film tearing voltage.

4. The impact resistance design method of silicone gel film material for straight rigid electronic display screen according to claim 1, characterized in that: The performance regulation design of the molecular structure of the silicone gel matrix described in step 2 is to control the dynamic cross-linking mode of the molecular chain of the silicone gel matrix, thereby achieving effective regulation of the elastic modulus, rate effect coefficient and damping coefficient of the silicone gel. The specific steps are as follows: 2A. By adjusting the content of the cross-linking agent, the initial cross-linking density of the silicone gel molecular chain is controlled, thereby obtaining a silicone gel with a corresponding elastic modulus; 2B. By adjusting the content of the tackifier, the interaction force between the silicone gel molecular chains is controlled to obtain silicone gel with a corresponding damping coefficient; 2C. By adjusting the proportion of catalysts, the dynamic entanglement effect of the silicone gel molecular chain is controlled, thereby achieving parameter design of the rate effect coefficient; 2D. By regulating the time and temperature of the cross-linking reaction, the cross-linking density and intermolecular force of silicone gel can be effectively controlled.

5. The impact resistance design method of silicone gel film material for straight rigid electronic display screen according to claim 1, characterized in that: The silicone gel matrix slurry in step 2 is composed of the following components: methyl vinyl silicone rubber, methyl MQ silicone resin, benzoyl peroxide, xylene, crosslinking agent, tackifier, inhibitor, catalyst and carbon nanotubes, wherein: The cross-linking agent is hydrogen-containing silicone oil; The tackifier is one of a silane coupling agent and a titanate coupling agent; The inhibitor is one of 1-ethynylcyclohexanol, 2-methyl-3-butyn-2-ol and 3,5-dimethyl-1-hexyn-3-ol; The catalyst is platinum catalyst PT4000.

6. The impact resistance design method of silicone gel film material for straight rigid electronic display screen according to claim 1, characterized in that: The preparation method of the silicone gel matrix slurry described in step 2 includes: (21), dissolving a formulated amount of methyl vinyl silicone rubber and a formulated amount of methyl MQ silicone resin in a formulated amount of xylene; (22), adding a formulated amount of inhibitor and a formulated amount of dibenzoyl peroxide, and mixing them uniformly to form a main material of a silicone gel matrix; (23) Add a formulated amount of a cross-linking agent, a formulated amount of a tackifier, a formulated amount of a catalyst, and a formulated amount of carbon nanotubes to the main material of the silicone gel matrix obtained in step (22), and stir evenly to obtain a silicone gel matrix slurry.

7. The impact resistance design method of silicone gel film material for straight rigid electronic display screen according to claim 1, characterized in that: Based on the total mass of the silicone gel matrix, the added amount of the FIAM impact reinforcement is 5%.

8. The impact resistance design method of silicone gel film material for straight rigid electronic display screen according to claim 6, characterized in that: In step 3, the FIAM impact reinforcement with non-Newtonian fluid effect is used to design a physical and chemical composite cross-linked network for the silicone gel matrix, and the steps of preparing the silicone gel film material include: (31) Add 5 parts of FIAM impact reinforcement directly to 100 parts of silicone gel matrix slurry at room temperature; (32), fully mixing the FIAM impact-resistant reinforcement and the silicone gel composite slurry, and then performing vacuum degassing treatment to obtain an impact-resistant composite silicone gel; (33) According to the high-temperature film-forming process, the impact-resistant composite silicone gel is cross-linked to obtain a silicone gel film material with a corresponding thickness facing the straight-panel rigid electronic display screen.

9. The impact resistance design method of silicone gel film material for straight rigid electronic display screen according to claim 8, characterized in that: The film forming process described in step (33) includes: (331) using a high-precision film applicator to coat the degassed impact-resistant composite silicone gel on the PET release film, with a coating thickness of 130 μm; (332) The PET-silicone gel film was placed in a vacuum oven at 80 °C for 5 min to pre-evaporate the solvent, mainly to prevent bubbles from appearing during the curing of the silicone gel; (333) The temperature of the vacuum oven is raised to 150 °C to perform a cross-linking reaction on the silicone gel for 8 min, thereby obtaining a silicone gel film material of a corresponding thickness facing a straight-panel rigid electronic display screen.

10. The impact resistance design method of silicone gel film material for straight rigid electronic display screen according to claim 1, characterized in that: The specific steps of step four are as follows: Based on the actual application conditions of silicone gel in the straight-panel rigid electronic display module, a systematic evaluation is conducted on the mechanical properties, impact energy absorption, peel strength, shading performance and film tearing voltage of the silicone gel film for the straight-panel rigid electronic display.

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