Liquid crystal elastomer composite material as well as preparation method and application thereof
By combining liquid crystal elastomer composite materials with room temperature phosphorescent materials, the problems of low sensitivity and poor environmental adaptability of traditional stress monitoring systems are solved, realizing direct visual monitoring of stress and high-sensitivity response.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- WUYI UNIV
- Filing Date
- 2025-12-19
- Publication Date
- 2026-05-01
AI Technical Summary
Traditional stress monitoring systems rely on electrical signals, have low sensitivity, cannot achieve direct visual monitoring of stress, are prone to failure in complex environments, and lack material compatibility and mechanical matching.
By employing liquid crystal elastomer composite materials and doping them with room temperature phosphorescent materials, the invisible stress is transformed into a visible optical signal through a chain reaction of stress-liquid crystal molecular structure change-signal output, enabling direct visual monitoring.
It achieves high sensitivity, wide range response and long-term stable visual monitoring of stress, requires no complicated instruments, is adaptable to various environments and has good material compatibility.
Smart Images
Figure CN121950286A_ABST
Abstract
Description
A liquid crystal elastomer composite material, its preparation method and application Technical Field
[0001] This invention relates to the field of polymer materials technology, and in particular to a liquid crystal elastomer composite material, its preparation method, and its application. Background Technology
[0002] Stress monitoring is a core component for ensuring the safety of engineering structures, improving the performance of industrial products, and promoting the development of high-end manufacturing technologies. It is widely used in fields such as building bridges, aerospace, flexible electronics, and biomedicine. However, traditional stress monitoring still largely relies on sensing systems based on traditional soft materials (such as ordinary elastic gels, rubber substrates, and resin-based strain gauge carriers). These systems have the following key technical defects in practical applications: First, they rely on electrical signals such as changes in resistance and voltage to indirectly reflect the stress state, requiring complex instruments for analysis and failing to achieve direct visual monitoring of stress. Furthermore, they have low sensitivity to capturing micro-stress, easily missing micro-damage and leading to the accumulation of safety hazards. Second, they are prone to failure in complex environments such as high and low temperatures and corrosion, exhibiting poor environmental adaptability. Third, in emerging monitoring scenarios such as flexible electronics and biological tissues, the objects being measured are often flexible substrates such as skin and flexible displays. Rigid sensors have poor mechanical matching with the substrate, easily leading to stress transmission distortion or interface delamination, resulting in insufficient material compatibility and mechanical matching.
[0003] Therefore, there is an urgent need for a polymer elastomer material that combines direct stress-signal conversion capability, wide range and high sensitivity response characteristics, and excellent long-term stability in order to break through the technical bottlenecks of traditional systems and meet the high-performance requirements of stress monitoring in different scenarios. Summary of the Invention
[0004] The present invention aims to at least solve one of the technical problems existing in the prior art. To this end, the first aspect of the present invention proposes a liquid crystal elastomer composite material, which has the characteristics of triple optical response changes of "lifetime-strength-color", high sensitivity and wide response range, and can efficiently complete real-time visual monitoring of stress without additional sensing components or complex detection equipment.
[0005] A second aspect of the present invention also provides a method for preparing a liquid crystal elastomer composite material.
[0006] A third aspect of the present invention also provides an application of a liquid crystal elastomer composite material.
[0007] According to a first aspect of the present invention, a liquid crystal elastomer composite material is provided, comprising a liquid crystal elastomer matrix and a room temperature phosphorescent material doped in the liquid crystal elastomer matrix; the room temperature phosphorescent material is a planar conjugated organic light-emitting material; and the room temperature phosphorescent material accounts for 0.1% to 10% of the total mass of the liquid crystal elastomer matrix.
[0008] According to a preferred embodiment of the present invention, the planar conjugated organic light-emitting material includes at least one of phenanthrene, benzo[a]phenanthrene, pyrene, benzo[a]pyrene, cyclohexene, or ovobenzene.
[0009] According to a preferred embodiment of the present invention, the planar conjugated organic light-emitting material is benzene.
[0010] According to a preferred embodiment of the present invention, the room temperature phosphorescent material accounts for 0.1% to 1% of the total mass.
[0011] According to a preferred embodiment of the present invention, the room temperature phosphorescent material accounts for 0.3% to 0.8% of the total mass.
[0012] According to a preferred embodiment of the present invention, the raw materials of the liquid crystal elastomer matrix include liquid crystal monomers, chain extenders, and crosslinking agents.
[0013] According to a preferred embodiment of the present invention, the total mass of the liquid crystal elastomer matrix includes the sum of the masses of the liquid crystal monomer, the chain extender, and the crosslinking agent.
[0014] According to a preferred embodiment of the present invention, the molar ratio of the liquid crystal monomer, the chain extender and the crosslinking agent is 1:(0.11~0.60):(0.20~0.44).
[0015] According to a preferred embodiment of the present invention, the liquid crystal monomer includes at least one of acrylate-based liquid crystal monomers, methacrylate-based liquid crystal monomers, and epoxy-based liquid crystal monomers.
[0016] According to a preferred embodiment of the present invention, the acrylate-based liquid crystal monomer includes at least one selected from 1,4-bis[4-(3-acryloyloxypropoxy)benzoic acid]-2-toluene (i.e., liquid crystal monomer RM257), 1,4-bis-[4-(6-acryloyloxyhexyloxy)benzoyloxy]-2-methylbenzene (i.e., liquid crystal monomer RM82), 4-cyanophenyl 4-(acryloyloxy)benzoate (i.e., liquid crystal monomer RM23), 4-methoxyphenyl 4-(acryloyloxy)benzoate, 4-butoxyphenyl 4-(acryloyloxy)benzoate, or 2-methyl-1,4-phenylenebis(4-(4-(acryloyloxy)butoxy)benzoate).
[0017] According to a preferred embodiment of the present invention, the acrylate-based liquid crystal monomers include 1,4-bis[4-(3-acryloyloxypropoxy)benzoic acid]-2-toluene (i.e., liquid crystal monomer RM257) and 1,4-bis-[4-(6-acryloyloxyhexyloxy)benzoyloxy]-2-methylbenzene (i.e., liquid crystal monomer RM82). Therefore, it possesses superior liquid crystal phase stability and polymerization reactivity, enabling more efficient construction of high-performance RTP-liquid crystal elastomer composite systems.
[0018] According to a preferred embodiment of the present invention, the methacrylate-based liquid crystal monomer includes at least one of 4-ethoxyphenyl 4-(methacryloyloxy)benzoate, 4-hexyloxybiphenyl-4'-ylmethacrylate, and cholesterol-based methacrylate.
[0019] According to a preferred embodiment of the present invention, the epoxy liquid crystal monomer includes at least one of hydroquinone diglycidyl ether type liquid crystal epoxy monomer and 3,3'5,5'-tetramethylbiphenyl bisphenol diglycidyl ether type liquid crystal epoxy monomer.
[0020] According to a preferred embodiment of the present invention, the epoxy liquid crystal monomer includes a hydroquinone diglycidyl ether type liquid crystal epoxy monomer, thereby possessing superior liquid crystal phase stability and polymerization reactivity, and enabling more efficient construction of high-performance RTP-liquid crystal elastomer composite systems.
[0021] According to a preferred embodiment of the present invention, the chain extender includes a chain extender containing a thiol group and / or a chain extender containing a double bond.
[0022] According to a preferred embodiment of the present invention, the chain extender further includes a chain extender containing double bonds, thereby enabling synergistic crosslinking with a chain extender containing thiol groups.
[0023] According to a preferred embodiment of the present invention, the thiol-containing chain extender comprises 3,6 Dioxane 1,8 At least one of octanedithiol, 1,2-ethanedithiol, 1,4-butanedithiol, and 1,6-hexanedithiol.
[0024] According to a preferred embodiment of the present invention, the chain extender containing double bonds includes 1,6-hexanediol diacrylate and / or polyethylene glycol diacrylate.
[0025] According to a preferred embodiment of the present invention, the crosslinking agent includes at least one of a polyfunctional acrylate crosslinking agent, an epoxy crosslinking agent, or a mercapto-olefin click reaction crosslinking agent.
[0026] According to a preferred embodiment of the present invention, the multifunctional acrylate crosslinking agent includes at least one of trimethylolpropane triacrylate (TMPTA), pentaerythritol triacrylate (PETA), and dipentaerythritol hexaacrylate (DPHA).
[0027] According to a preferred embodiment of the present invention, the epoxy crosslinking agent comprises tris(epoxypropyl)isocyanurate (TGIC) and / or tetraglycidyl diaminodiphenylmethane (TGDAM).
[0028] According to a preferred embodiment of the present invention, the mercapto-olefin click crosslinking agent comprises tris(2-mercaptoethyl) isocyanurate (TEMPIC) and / or pentaerythritol tetra(3-mercaptopropionate) (PETMP).
[0029] According to a preferred embodiment of the present invention, the raw materials of the liquid crystal elastomer matrix further include solvent and catalyst.
[0030] According to a preferred embodiment of the present invention, the solvent includes at least one selected from dichloromethane, ethyl acetate, N,N-dimethylformamide, and N,N-dimethylacetamide.
[0031] According to a preferred embodiment of the present invention, the catalyst comprises at least one selected from di-n-propylamine, triethylamine, hexylamine, 1,8-diazabicycloundec-7-ene, 1,5-diazabicyclo[4.3.0]non-5-ene, dimethylphenylphosphine, methyldiphenylphosphine, triphenylphosphine, or tributylphosphine.
[0032] The liquid crystal elastomer composite material according to embodiments of the present invention has at least the following beneficial effects: the present invention dops a specific amount of room temperature phosphorescent material into a liquid crystal elastomer matrix; it enables stress visualization monitoring with high sensitivity and a wide response range. The core is to convert invisible stress into a visible optical signal through a chain reaction of "stress-liquid crystal molecule structure change-signal output," utilizing the phosphorescence intensity-color-lifetime changes of the room temperature phosphorescent material.
[0033] Furthermore, when the liquid crystal elastomer composite material of the present invention is stretched, the liquid crystal elastomer matrix first bears the stress, and then undergoes an orientation change under the stress, such as changing from a multi-domain liquid crystal cell arrangement to an orientation along the stress direction, while simultaneously causing the matrix molecular chains to undergo regular deformation. This deformation is synchronously transmitted to the room-temperature phosphorescent material dispersed in the matrix. The room-temperature phosphorescent material will undergo a change in excited-state structure due to stress, producing a recognizable change in optical signal, and the change in optical signal can meet the condition of "direct perception by the naked eye" without the need for complex instruments. The room-temperature phosphorescent material can form a significant "afterglow" due to its long-life phosphorescence (milliseconds to seconds). Stress changes will bring about differences in brightness or afterglow, which can be directly observed by the naked eye. For example, when the stress increases, the material phosphorescence is brighter, the afterglow is longer, and the lifespan is longer; or stress causes a shift in phosphorescence wavelength, and the stress magnitude can be intuitively distinguished by the difference in afterglow color, further improving the visual recognition.
[0034] According to a second aspect of the present invention, a method for preparing a liquid crystal elastomer composite material as described in the first aspect of the present invention includes the following steps: mixing the raw materials for preparing the liquid crystal elastomer matrix and the room temperature phosphorescent material, performing a polymerization reaction, curing, and drying to obtain the final product.
[0035] According to a preferred embodiment of the present invention, the liquid crystal elastomer composite material is prepared by the following method: S1, in the presence of a solvent, the liquid crystal monomer, the chain extender, and the crosslinking agent are mixed to obtain a mixture; S2, the mixture, a room temperature phosphorescent material, and a catalyst are mixed and subjected to polymerization reaction, curing, and drying to obtain the final product.
[0036] According to a preferred embodiment of the present invention, the curing time is 5 h to 24 h.
[0037] According to a preferred embodiment of the present invention, the curing temperature is 20°C to 30°C.
[0038] According to a preferred embodiment of the present invention, the drying temperature is 40°C to 100°C.
[0039] A third aspect of the present invention provides an application of the above-described liquid crystal elastomer composite material in stress visualization monitoring.
[0040] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. Attached Figure Description
[0041] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 is a schematic diagram of the preparation process of the liquid crystal elastomer composite material of Embodiment 1 of the present invention; Figure 2 is a schematic diagram of an in-situ strain gauge used to test the in-situ delayed emission spectrum; Figure 3 is an image taken during mechanical stretching of the standard tensile specimen prepared in Embodiment 1 of the present invention; Figure 4 is an image taken during mechanical stretching of the standard tensile specimen prepared in Embodiment 2 of the present invention; Figure 5 is a graph showing the relationship between stress and phosphorescence intensity of the standard tensile specimen prepared in Embodiment 1 of the present invention; Figure 6 is a graph showing the relationship between stress and phosphorescence intensity of the standard tensile specimen prepared in Embodiment 2 of the present invention. Detailed Implementation
[0042] The following are specific embodiments of the present invention, and the technical solutions of the present invention will be further described in conjunction with the embodiments, but the present invention is not limited to these embodiments.
[0043] Unless otherwise specified, the reagents, methods and equipment used in this invention are all conventional reagents, methods and equipment in this technical field.
[0044] In some embodiments, the present invention provides a liquid crystal elastomer composite material, comprising a liquid crystal elastomer matrix and a room temperature phosphorescent material doped in the liquid crystal elastomer matrix; the room temperature phosphorescent material is a planar conjugated organic light-emitting material; the room temperature phosphorescent material accounts for 0.1% to 10% of the total mass of the liquid crystal elastomer matrix.
[0045] It is understood that this invention involves doping a specific amount of room-temperature phosphorescent material into a liquid crystal elastomer matrix; this enables stress visualization monitoring with high sensitivity and a wide response range. The core principle is to utilize a chain reaction of "stress-liquid crystal molecule structure change-signal output," using room-temperature phosphorescent material to convert invisible stress into a visible optical signal.
[0046] Furthermore, when the liquid crystal elastomer composite material of the present invention is stretched, the liquid crystal elastomer matrix first bears the stress, and then undergoes an orientation change under the stress, such as changing from a multi-domain liquid crystal structure to an orientation along the stress direction, while simultaneously causing the matrix molecular chains to undergo regular deformation. This deformation is synchronously transmitted to the room-temperature phosphorescent material dispersed in the matrix. The room-temperature phosphorescent material will undergo a change in excited-state structure due to stress, producing a recognizable change in optical signal, and the change in optical signal can meet the condition of being "directly perceptible to the naked eye" without the need for complex instruments. The room-temperature phosphorescent material can form a significant "afterglow" due to its long-life phosphorescence (milliseconds to seconds). Stress changes will bring about differences in brightness or afterglow, which can be directly observed with the naked eye. For example, when the stress increases, the material phosphorescence is brighter, the afterglow is longer, and the lifespan is longer; or stress causes a shift in phosphorescence wavelength, and the stress magnitude can be intuitively distinguished by the difference in afterglow color, further improving the visual recognition.
[0047] In some embodiments of the present invention, the planar conjugated organic light-emitting material includes at least one of phenanthrene, benzo[a]phenanthrene, pyrene, benzo[a]pyrene, cyclohexene, or ovobenzene.
[0048] In some embodiments of the present invention, the planar conjugated organic light-emitting material is benzene. This results in better light emission.
[0049] In some embodiments of the present invention, the room-temperature phosphorescent material accounts for 0.1% to 10% of the total mass. For example, it includes 0.1%, 0.3%, 0.5%, 0.6%, 0.8%, 1.0%, 1.4%, 1.8%, 2%, 2.4%, 2.8%, 3%, 3.5%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, or any sub-range of any two of the above values.
[0050] In some embodiments of the present invention, the room-temperature phosphorescent material accounts for 0.1% to 1% of the total mass. For example, it includes 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1.0%, or any sub-range consisting of any two of the above values.
[0051] In some embodiments of the present invention, the room-temperature phosphorescent material accounts for 0.3% to 0.8% of the total mass. For example, it includes sub-ranges such as 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, or any two of the above values. Thus, within the above range, the afterglow color of the liquid crystal elastomer composite material is more pronounced and longer-lasting, the phosphorescence intensity is higher, and the phosphorescence lifetime is longer.
[0052] In some embodiments of the present invention, the raw materials of the liquid crystal elastomer matrix include liquid crystal monomers, chain extenders, and crosslinking agents.
[0053] In some embodiments of the present invention, the total mass of the liquid crystal elastomer matrix includes the sum of the masses of the liquid crystal monomer, the chain extender, and the crosslinking agent.
[0054] In some embodiments of the present invention, the molar ratio of liquid crystal monomer, chain extender and crosslinking agent is 1:(0.11~0.60):(0.20~0.44).
[0055] In some embodiments of the present invention, the liquid crystal monomer includes at least one of acrylate-based liquid crystal monomers, methacrylate-based liquid crystal monomers, and epoxy-based liquid crystal monomers.
[0056] In some embodiments of the present invention, the acrylate-based liquid crystal monomer includes at least one selected from 1,4-bis[4-(3-acryloyloxypropoxy)benzoic acid]-2-toluene (i.e., liquid crystal monomer RM257), 1,4-bis-[4-(6-acryloyloxyhexyloxy)benzoyloxy]-2-methylbenzene (i.e., liquid crystal monomer RM82), 4-cyanophenyl 4-(acryloyloxy)benzoate (i.e., liquid crystal monomer RM23), 4-methoxyphenyl 4-(acryloyloxy)benzoate, 4-butoxyphenyl 4-(acryloyloxy)benzoate, or 2-methyl-1,4-phenylenebis(4-(4-(acryloyloxy)butoxy)benzoate).
[0057] In some embodiments of the present invention, the acrylate-based liquid crystal monomers include 1,4-bis[4-(3-acryloyloxypropoxy)benzoic acid]-2-toluene (i.e., liquid crystal monomer RM257) and 1,4-bis-[4-(6-acryloyloxyhexyloxy)benzoyloxy]-2-methylbenzene (i.e., liquid crystal monomer RM82). Therefore, they possess superior liquid crystal phase stability and polymerization reactivity, enabling more efficient construction of high-performance RTP-liquid crystal elastomer composite systems.
[0058] In some embodiments of the present invention, the methacrylate-based liquid crystal monomer includes at least one of 4-ethoxyphenyl 4-(methacryloyloxy)benzoate, 4-hexyloxybiphenyl-4'-ylmethacrylate, and cholesterol-based methacrylate.
[0059] In some embodiments of the present invention, the epoxy liquid crystal monomer includes at least one of hydroquinone diglycidyl ether type liquid crystal epoxy monomer and 3,3'5,5'-tetramethylbiphenyl bisphenol diglycidyl ether type liquid crystal epoxy monomer.
[0060] In some embodiments of the present invention, the epoxy liquid crystal monomer includes a hydroquinone diglycidyl ether type liquid crystal epoxy monomer, thereby possessing superior liquid crystal phase stability and polymerization reactivity, and enabling more efficient construction of high-performance RTP-liquid crystal elastomer composite systems.
[0061] In some embodiments of the present invention, the chain extender includes a thiol-containing chain extender.
[0062] In some embodiments of the present invention, the chain extender further includes a chain extender containing a double bond, thereby enabling synergistic crosslinking with a chain extender containing a thiol group.
[0063] In some embodiments of the present invention, the thiol-containing chain extender comprises 3,6 Dioxane 1,8 At least one of octanedithiol, 1,2-ethanedithiol, 1,4-butanedithiol, and 1,6-hexanedithiol.
[0064] In some embodiments of the present invention, the chain extender containing double bonds includes 1,6-hexanediol diacrylate and / or polyethylene glycol diacrylate.
[0065] In some embodiments of the present invention, the crosslinking agent includes at least one of polyfunctional acrylate crosslinking agents, epoxy crosslinking agents, or mercapto-olefin click reaction crosslinking agents.
[0066] In some embodiments of the present invention, the multifunctional acrylate crosslinking agent includes at least one of trimethylolpropane triacrylate (TMPTA), pentaerythritol triacrylate (PETA), and dipentaerythritol hexaacrylate (DPHA).
[0067] In some embodiments of the present invention, the epoxy crosslinking agent includes tris(epoxypropyl)isocyanurate (TGIC) and / or tetraglycidyl diaminodiphenylmethane (TGDAM).
[0068] In some embodiments of the present invention, the mercapto-olefin click crosslinking agent includes tris(2-mercaptoethyl) isocyanurate (TEMPIC) and / or pentaerythritol tetra(3-mercaptopropionate) (PETMP).
[0069] In some embodiments of the present invention, the siloxane crosslinking agent includes tetramethyltetravinylcyclotetrasiloxane (D4Vi) and / or methyltrimethoxysilane (MTMS).
[0070] In some embodiments of the present invention, the raw materials for the liquid crystal elastomer matrix also include solvents and catalysts.
[0071] In some embodiments of the present invention, the solvent includes at least one selected from dichloromethane, ethyl acetate, N,N-dimethylformamide, and N,N-dimethylacetamide.
[0072] In some embodiments of the present invention, the catalyst includes at least one of di-n-propylamine, triethylamine, hexylamine, 1,8-diazabicycloundec-7-ene, 1,5-diazabicyclo[4.3.0]non-5-ene, dimethylphenylphosphine, methyldiphenylphosphine, triphenylphosphine, or tributylphosphine.
[0073] In some embodiments of the present invention, a method for preparing a liquid crystal elastomer composite material as described in the first aspect of the present invention is provided, comprising the following steps: mixing various raw materials for preparing a liquid crystal elastomer matrix with a room temperature phosphorescent material, performing a polymerization reaction, curing, and drying to obtain the final product.
[0074] In some embodiments of the present invention, the liquid crystal elastomer composite material is prepared by the following method: S1, in the presence of a solvent, liquid crystal monomer, chain extender and crosslinking agent are mixed to obtain a mixture; S2, the mixture, room temperature phosphorescent material and catalyst are mixed and subjected to polymerization reaction, curing and drying to obtain the final product.
[0075] In some embodiments of the present invention, the curing time is 5 h to 24 h. For example, it includes 5 h, 6 h, 7 h, 8 h, 9 h, 10 h, 12 h, 14 h, 16 h, 18 h, 20 h, 22 h, 24 h, or any sub-range composed of any two of the above values.
[0076] In some embodiments of the present invention, the curing temperature is 20°C to 30°C. For example, it includes 20°C, 21°C, 22°C, 23°C, 24°C, 25°C, 26°C, 27°C, 28°C, 29°C, 30°C, or any sub-range consisting of any two of the above values.
[0077] In some embodiments of the present invention, the drying temperature is 40°C to 100°C. For example, it includes 40°C, 45°C, 50°C, 55°C, 60°C, 70°C, 75°C, 80°C, 85°C, 90°C, 100°C, or any sub-range consisting of any two of the above values.
[0078] In some embodiments of the present invention, the present invention provides an application of the above-described liquid crystal elastomer composite material in stress visualization monitoring.
[0079] In embodiments of the present invention, some of the raw materials are as follows: liquid crystal monomer: 1,4-bis[4-(3-acryloyloxypropoxy)benzoic acid]-2-toluene (RM257); chain extender: 3,6 Dioxane 1,8 Octanedithiol (EDDET); Crosslinking agent: Pentaerythritol tetra-3-mercaptopropionate (PETMP); Catalyst: Di-n-propylamine (DPA).
[0080] All the above raw materials were purchased from Shanghai Jizhi Biochemical Technology Co., Ltd.
[0081] Example 1 This example provides a liquid crystal elastomer composite material. The preparation process is shown in Figure 1. Based on the total mass of liquid crystal monomers, chain extenders, and crosslinking agents, benzene accounts for 0.5% of the total mass. The specific preparation steps are as follows: S1, Dissolve 1.7658g (3.00mmol) of RM257, 0.0602g (0.33mmol) of EDDET, and 0.6499g (1.33mmol) of PETMP in 15ml of DCM, and stir the solution at room temperature until all solid substances are completely dissolved; obtain a mixture; S2, Then add catalyst DPA (45ul) and benzene (0.0124g) to the mixture and continue stirring the mixture at room temperature until all components are uniformly dispersed; Pour the stirred mixture into a PTFE (polytetrafluoroethylene) mold and place it at room temperature for 12 hours; Curing for 1 hour to remove bubbles, and then placing the fresh sample in a vacuum oven and drying the sample at 80°C for 24 hours to obtain the final liquid crystal elastomer composite material.
[0082] Example 2 This example provides a liquid crystal elastomer composite material, with benzene accounting for 0.5% of the total mass. The specific preparation steps are as follows: S1, Dissolve 1.7658g (3.00mmol) of RM257, 0.1823g (1.00mmol) of EDDET and 0.4887g (1.00mmol) of PETMP in 15ml of DCM, and stir the solution at room temperature until all solid substances are completely dissolved to obtain a mixture; S2, Add catalyst DPA (45ul) and benzene (0.0122g) to the mixture and continue stirring the mixture at room temperature until all components are uniformly dispersed; Pour the stirred mixture into a PTFE (polytetrafluoroethylene) mold and place it at room temperature for 12 hours; Curing for 1 hour to remove bubbles, and then placing the fresh sample in a vacuum oven and drying the sample at 80°C for 24 hours to obtain the liquid crystal elastomer composite material.
[0083] Performance testing involved processing the liquid crystal elastomer composite materials of Examples 1 and 2 of this invention into standard tensile specimens (50mm × 8.5mm × 16mm × 4mm) conforming to GB / T 528-2009 Type 3. Phosphorescence performance under different stresses (100% of the original length of the specimen film, stretched to 225%) was tested in a darkroom environment using an in-situ strain gauge for testing in-situ delayed emission spectra (as shown in Figure 2). The results for the standard tensile specimen of Example 1 are shown in Figure 3. When the standard specimen was stretched laterally, the proportion of the green afterglow component gradually increased with increasing stress, while the proportion of the red afterglow component gradually decreased. This color change allows for direct visualization and monitoring of stress.
[0084] The results of the standard tensile specimen in Example 2 are shown in Figure 4. When the standard specimen is stretched laterally, as the stress increases, the proportion of the yellow-green afterglow component gradually decreases, while the proportion of the red afterglow component gradually increases. This indicates that the greater the stress, the more red the afterglow color is displayed. The stress can be directly visualized and monitored through the change in color.
[0085] Furthermore, the stress-phosphorescence intensity relationship of the standard tensile specimens of Example 1 and Example 2 was tested respectively, and the results are shown in Figure 5 and Figure 6 respectively. The phosphorescence intensity of the standard tensile specimens of Example 1 and Example 2 at 535nm increases with the increase of stress.
[0086] The present invention has been described in detail above with reference to the embodiments of the present invention. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.
Claims
1. A liquid crystal elastomer composite material, characterized in that, The product includes a liquid crystal elastomer matrix and a room-temperature phosphorescent material doped in the liquid crystal elastomer matrix; the room-temperature phosphorescent material is a planar conjugated organic light-emitting material; the room-temperature phosphorescent material accounts for 0.1% to 10% of the total mass of the liquid crystal elastomer matrix.
2. The liquid crystal elastomer composite material according to claim 1, characterized in that, The planar conjugated organic light-emitting material includes at least one of benzo[a]phenylene, benzo[a]phenanthrene, pyrene, benzo[a]pyrene, cyclohexene, or ovobenzene.
3. The liquid crystal elastomer composite material according to claim 1, characterized in that, The room-temperature phosphorescent material accounts for 0.3% to 0.8% of the total mass.
4. The liquid crystal elastomer composite material according to claim 1, characterized in that, The raw materials for the liquid crystal elastomer matrix include liquid crystal monomers, chain extenders, and crosslinking agents.
5. The liquid crystal elastomer composite material according to claim 4, characterized in that, The molar ratio of the liquid crystal monomer, chain extender and crosslinking agent is 1:(0.11~0.60):(0.20~0.44).
6. The liquid crystal elastomer composite material according to claim 4, characterized in that, The liquid crystal monomer includes at least one of acrylate-based liquid crystal monomers, methacrylate-based liquid crystal monomers, or epoxy-based liquid crystal monomers.
7. The liquid crystal elastomer composite material according to claim 4, characterized in that, The chain extender includes chain extenders containing thiol groups.
8. The liquid crystal elastomer composite material according to claim 4, characterized in that, The crosslinking agent includes at least one of polyfunctional acrylate crosslinking agents, epoxy crosslinking agents, or mercapto-olefin click reaction crosslinking agents.
9. A method for preparing the liquid crystal elastomer composite material according to any one of claims 1 to 8, characterized in that, The process includes the following steps: mixing and polymerizing the raw materials for preparing the liquid crystal elastomer matrix with the room temperature phosphorescent material, followed by curing and drying.
10. The application of the liquid crystal elastomer composite material according to any one of claims 1 to 8 in stress visualization monitoring.