A liquid crystal polymer material, its preparation method and application

Abstract

This invention discloses a liquid crystal polymer material, its preparation method, and its applications, belonging to the field of polymer materials technology. The product comprises the following components in parts by weight: 100 parts liquid crystal polymer, 10-100 parts syndiotactic polystyrene, and 20-60 parts glass fiber. By adding glass fiber as a filler to the liquid crystal polymer matrix resin, simultaneously introducing syndiotactic polystyrene, and controlling the aspect ratio of the glass fiber, the shrinkage difference in different directions during processing can be effectively reduced. The resulting product has high strength and high processing performance, enabling rapid processing and high production value.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, specifically to a liquid crystal polymer material, its preparation method, and its application. Background Technology

[0002] Liquid crystal polymers (LCPs) are widely used in various fields such as electronics, automobiles, and industrial manufacturing due to their excellent mechanical strength, heat resistance, and dielectric properties. However, the high rigidity of the molecular chains in LCPs makes them prone to forming highly oriented structures during processing. This leads to excessive differences in shrinkage rates in the flow direction (MD) and vertical direction (TD) during processing, resulting in severe deformation of the finished product and making it difficult to meet the requirements of precision assembly scenarios. To address this, researchers have attempted to introduce a certain amount of particulate solid filler into the product to suppress the shrinkage. However, this approach may significantly reduce the mechanical strength of precision products, drastically decreasing product yield and application value. Furthermore, during high-speed processing, the resin components and solid fillers may separate, resulting in inconsistent material composition between the near-gate and far-gate areas, which in turn prevents uniform processing and the production of dimensionally stable products. Summary of the Invention

[0003] Based on the deficiencies of existing technologies, the present invention aims to provide a liquid crystal polymer material. This product, by adding glass fiber as a filler to the liquid crystal polymer matrix resin and introducing syndiotactic polystyrene composite, and by controlling the aspect ratio of the glass fiber, can effectively reduce the shrinkage difference in different directions during processing. The resulting product has high strength and high processing performance, enabling rapid processing and high production value.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A liquid crystal polymer material comprising the following components in parts by weight: 100 parts liquid crystal polymer, 10-100 parts syndiotactic polystyrene, 20-60 parts glass fiber; The weight-average molecular weight of the syndiotactic polystyrene is ≥160,000; The average aspect ratio of the glass fibers retained in the liquid crystal polymer material is 10~16.

[0005] To address the issue of excessive shrinkage differences between the flow direction and the vertical direction during liquid crystal polymer processing, which can lead to warping and bending deformation, especially when processing into thin or elongated products, this invention employs non-particulate glass fibers, which disperse in the matrix resin to form a three-dimensional structure, as a functional filler. Simultaneously, syndiotactic polystyrene is compounded as a component. Syndiotactic polystyrene, a highly crystalline polymer, exhibits unique spherulite growth during crystallization. Combined with the three-dimensional distribution of the glass fibers, this interferes with the ordered orientation of the liquid crystal polymer molecular chains, suppressing the differential shrinkage in different directions and significantly reducing the ratio of shrinkage rates in different directions.

[0006] However, when introducing the syndiotactic polystyrene, the molecular weight cannot be too small. Otherwise, in addition to affecting the strength of the product, the low molecular chain entanglement will prevent it from being well fixed with the glass fiber and liquid crystal polymer, thus affecting the processing uniformity of the product. At the same time, the aspect ratio of the glass fiber in the product will affect its distribution. If the aspect ratio is not appropriate, it may not only lead to a lower uniformity of glass fiber distribution and local cross-stacking of glass fibers, resulting in the inability to reduce the shrinkage difference in different directions of the product, but may also affect the strength and processing performance of the product, significantly reducing its pass rate during high-speed processing. Therefore, the aspect ratio of the glass fiber needs to be controlled within a specific range.

[0007] Preferably, in the liquid crystal polymer material, the syndiotactic polystyrene is in the range of 10 parts, 20 parts, 30 parts, 40 parts, 50 parts, 60 parts, 72 parts, 80 parts, 90 parts, and 100 parts by weight, or any two of these values, and the glass fiber is in the range of 20 parts, 30 parts, 40 parts, 50 parts, and 60 parts by weight, or any two of these values.

[0008] More preferably, the liquid crystal polymer material comprises the following components in parts by weight: 100 parts liquid crystal polymer, 40-80 parts syndiotactic polystyrene, and 30-40 parts glass fiber.

[0009] The amount of syndiotactic polystyrene and glass fiber introduced will affect the tensile strength, processing performance and shrinkage ratio in different directions of the product. When the addition amount of the two is preferably in the above ratio, the product can achieve a better overall performance level by balancing the three properties.

[0010] Preferably, the melting point of the liquid crystal polymer is 270~350℃.

[0011] More preferably, the liquid crystal polymer material contains a liquid crystal polymer content of ≥40wt%.

[0012] It should be noted that commonly used liquid crystal polymer resins in the art can be used in this invention. For example, liquid crystal polymer resins whose structural units are derived from one or more of aromatic hydroxycarboxylic acids and aromatic dicarboxylic acids, or aromatic diols, aromatic hydroxyamines, or aromatic diamines; or liquid crystal polymer resins whose structural units are derived from different aromatic hydroxycarboxylic acids; or liquid crystal polymer resins whose structural units are derived from at least one compound of aromatic dicarboxylic acids and aromatic diols, aromatic hydroxyamines, or aromatic diamines; or liquid crystal polymer resins derived from the polymerization of polyesters such as polyethylene terephthalate with aromatic hydroxycarboxylic acids.

[0013] Preferably, the liquid crystal polymer includes at least one of aromatic thermoplastic polyester and aromatic lyotropic polyester; More preferably, the structural units of the liquid crystal polymer include at least one derived from p-hydroxybenzoic acid, 4,4-dihydroxybiphenyl, phthalic acid, and terephthalic acid.

[0014] The melting point of the liquid crystal polymer was determined with reference to ISO 11357-2023 using a NETZSCH DSC 200 F3 instrument. The temperature was increased from room temperature to above the melting point at a rate of 10°C / min, then decreased to room temperature at a rate of 10°C / min, and finally increased to 30°C above the melting point at a rate of 10°C / min. The melting point was obtained by taking the highest point of the melting peak of the curve during the second heating.

[0015] Preferably, the melt viscosity of the liquid crystal polymer at a melting point of +15°C and a shear rate of 1000 / s is 10~50 Pa·s.

[0016] More preferably, the melt viscosity is directly measured using a capillary rheometer.

[0017] Preferably, the melting point of the syndiotactic polystyrene is 260~280℃.

[0018] The melting point test method for the syndiotactic polystyrene is based on ISO 11357-2023, using a NETZSCH DSC 200 F3 thermometer. The temperature is increased from room temperature to above the melting point at a rate of 10°C / min, then decreased to room temperature at a rate of 10°C / min, and finally increased to 30°C above the melting point at a rate of 10°C / min. The melting point is obtained by taking the highest point of the melting peak of the curve during the second heating.

[0019] Preferably, the weight-average molecular weight of the syndiotactic polystyrene is 160,000 to 230,000.

[0020] More preferably, the weight-average molecular weight of the syndiotactic polystyrene is one or any two of the following values: 160,000, 170,000, 180,000, 190,000, 200,000, 210,000, 220,000, and 230,000.

[0021] Preferably, the molecular weight distribution of the syndiotactic polystyrene can be 1.6 to 2.1.

[0022] It should be noted that the test method for the weight-average molecular weight and molecular weight distribution of syndiotactic polystyrene described in this invention is as follows: A high-temperature gel permeation chromatography system (GPC-IR, Polymer Char, Spain, equipped with dual infrared and viscosity detectors) was used, with 1,2,4-trichlorobenzene as the mobile phase, a flow rate of 1.0 mL / min, a column temperature of 160℃, a detector temperature of 160℃, and an injector temperature of 160℃. A calibration curve was established using polystyrene standards (weight-average molecular weight range: 266-12,900,000 g / mol). The sample was dissolved in trichlorobenzene (concentration 0.125 mg / mL), and the injection volume was 200 μL. The data were processed using GPC ONE software to obtain the weight-average molecular weight (Mw), and the molecular weight distribution was calculated simultaneously.

[0023] It should be noted that the syndiotactic polystyrene described in this invention can be a commercially available product or a self-made product, and there is no limitation on this. When the component is a self-made product, it can be prepared by referring to CN112646066B, a catalytic polymerization system and polymerization method for styrene polymerization, and the resulting polystyrene is prepared by the following method: At 50~90℃, toluene, styrene, methylaluminoxane toluene solution and catalyst solution are added to the reactor and mixed for 15~150 min. Then acidified ethanol is added and stirred thoroughly. After filtration, the resulting solid is dried and purified to obtain the syndiotactic polystyrene.

[0024] Preferably, the catalyst comprises at least one of pentamethylcyclopentadienyl-4-quinolinoxy-dimethoxytitanium, pentamethylcyclopentadienyl-(3-methyl-4-quinolinoxy)-dimethoxytitanium, and pentamethylcyclopentadienyl-(3,5-di(trifluoromethyl)-4-quinolinoxy)-dimethoxytitanium.

[0025] More preferably, the molar ratio of the methylaluminoxane to the catalyst is (50~20000):1; More preferably, the molar ratio of the methylaluminoxane to the catalyst is (200~10000):1.

[0026] More preferably, the volume ratio of the toluene, styrene, methylaluminoxane toluene solution and the catalyst solution is (2~10):(4~6):(4~8):1.

[0027] It should be noted that the average aspect ratio of the glass fiber retained in the liquid crystal polymer material described in this invention refers to the average of the aspect ratios calculated from the final retained length and retained diameter of the glass fiber in the product after the glass fiber is compounded with other components and processed into liquid crystal polymer material. This average aspect ratio is not the same as the average aspect ratio of the glass fiber raw material or the weight average fiber length of the glass fiber raw material commonly found in polyester products in the prior art. Those skilled in the art can use raw glass fibers of different sizes to obtain different retained aspect ratios of the glass fiber in the product according to actual needs, or they can obtain them by using the same raw material but setting the processing parameters during processing. No specific limitation is made in this regard.

[0028] The average retained aspect ratio of glass fibers in the liquid crystal polymer material of the present invention can be confirmed in the following way: First, the liquid crystal polymer material is calcined at 650°C for 30 minutes to remove resin and retain inorganic matter. Glass fibers are then screened by ultrasonic treatment and uniformly dispersed in water. Two hundred glass fibers with intact appearance are selected by observation and testing using a two-dimensional microscope. The retained diameter and retained length of each glass fiber are measured (when measuring the diameter, the middle position of the glass fiber is selected). The aspect ratio (retained length / retained diameter) is calculated based on the retained diameter and retained length. Then, the average aspect ratio of the 200 glass fibers is calculated, which is the average retained aspect ratio of the glass fibers in the liquid crystal polymer material.

[0029] Preferably, the average aspect ratio of the glass fiber retained in the liquid crystal polymer material is a range of one or both of 10, 10.5, 11, 12, 13, 14, 15, and 16.

[0030] More preferably, the average aspect ratio of the glass fiber retained in the liquid crystal polymer is 10.6 to 15.

[0031] When the average aspect ratio of the glass fiber retained in the liquid crystal polymer is further preferably within 10.6 to 15, the strength of the product will not be greatly affected, and the difference in dimensional shrinkage in different directions of the product will be further reduced. At the same time, the processing performance of the product is better, and the pass rate is higher during high-speed processing.

[0032] Preferably, the glass fiber has a retention length of 50~250μm and a diameter of 8~15μm in the liquid crystal polymer.

[0033] Preferably, the average length of the glass fiber is 1 to 10 mm, and the average diameter of the glass fiber is 9 to 13 μm, more preferably 10 to 13 μm.

[0034] It should be noted that the average length and average diameter of the glass fibers in the liquid crystal polymer material described in this invention refer to the initial average length and average diameter of the glass fibers before the liquid crystal polymer material is melt-extruded and granulated.

[0035] The test method for the average length and average diameter of the glass fiber is as follows: the glass fiber is uniformly dispersed in water by ultrasonication and then observed, tested and confirmed by a two-dimensional microscope. The number of glass fibers selected is 200, and the average value is calculated.

[0036] In one embodiment, the liquid crystal polymer material of the present invention does not contain any other inorganic fillers besides glass fibers.

[0037] Based on the needs of the actual product, those skilled in the art may also appropriately introduce some additives commonly used in LCP products without affecting the product performance, such as antioxidants to improve the product's conventional oxidation resistance, lubricants to improve the product's processing performance, etc. The weight parts of the additives can be 0.01 to 1 part.

[0038] Another object of the present invention is to provide a method for preparing the liquid crystal polymer material, comprising the following steps: The components are added to a screw extruder for melt extrusion and granulation to obtain the liquid crystal polymer material.

[0039] Preferably, the heating temperature of the screw extruder is T℃, and the screw speed is 300~400rpm; T=Ta+(5~20)℃, where Ta is the melting point of the liquid crystal polymer in the component, specifically, T can be Ta+5℃, Ta+10℃, Ta+15℃, Ta+20℃, etc.

[0040] The preparation method of the liquid crystal polymer material described in this invention is simple, requires little equipment, and can be industrialized for large-scale production.

[0041] Preferably, the screw extruder is a twin-screw extruder.

[0042] Specifically, when the screw extruder is working, the feeding port of the glass fiber can be the same as or different from other components. As mentioned above, the average length-to-diameter ratio of the glass fiber in the product of this invention can be adjusted by controlling parameters during processing. In this invention, after the glass fiber is added, the first, second, third, and fourth side feeding ports of the twin-screw extruder are sequentially moved away from the motor end and closer to the extruder outlet. Since the glass fiber will break and shorten in length due to shearing by the screw in the extruder, glass fibers with different retention lengths and diameters can be obtained by adding them from side feeding ports at different positions. If the glass fiber is added from the side feeding port closer to the motor end (e.g., the first side feeding port), the glass fiber... The glass fiber experiences a longer shearing time in the extruder, resulting in a shorter retention length. If the glass fiber is added from a side feed port away from the motor end (e.g., the fourth side feed port), the shearing time in the extruder is shorter, resulting in a longer retention length. A similar pattern exists for the diameter of the glass fiber during processing. This invention adjusts the average length-to-diameter ratio of the retained glass fiber by using different raw materials in combination with the selection of the processing feed port, but it is not limited to this. Those skilled in the art can also control it by adjusting the screw speed. The faster the screw speed, the greater the shearing force on the glass fiber, and the shorter the retention length and diameter. Therefore, when the glass fiber is added to the screw extruder, it can be added from any one of the first, second, third, or fourth side feed ports.

[0043] Another object of the present invention is to provide the application of the liquid crystal polymer material in the fabrication of high-precision structural components.

[0044] Preferably, the high-precision structural component includes an optical device component.

[0045] Another object of the present invention is to provide an optical device component comprising the liquid crystal polymer material described herein.

[0046] Specifically, the optical device component includes an optical lens module, which includes a main body and a base.

[0047] The liquid crystal polymer material described in this invention has high tensile strength and can be used in various stress scenarios. During processing, due to the interaction of the components, a high yield rate can be achieved even at high processing rates. Furthermore, the difference in shrinkage rate between the flow direction and the vertical direction during processing is small. Even products with specific structural designs (such as thin parts, for example, wall thickness ≤1.5mm or ≤0.8mm, or slender strip parts, for example, the dimension of the part in one direction is ≤1.5mm or ≤0.8mm) will not show significant deformation, resulting in high production and application value.

[0048] The beneficial effects of this invention are that it provides a liquid crystal polymer material. This product, by adding glass fiber as a filler to the liquid crystal polymer matrix resin and introducing syndiotactic polystyrene composite, and by controlling the aspect ratio of the glass fiber, can effectively reduce the shrinkage difference in different directions during processing. The resulting product has high strength and high processing performance, can achieve rapid processing, and has high production value. Detailed Implementation

[0049] To better illustrate the purpose, technical solution, and advantages of this invention, the invention will be further described below with reference to specific embodiments and comparative examples. The purpose of this description is to provide a detailed understanding of the invention, not to limit its scope. All other embodiments obtained by those skilled in the art without inventive effort are within the protection scope of this invention. Unless otherwise specified, the experimental reagents and instruments involved in the implementation of this invention are commonly used reagents and instruments.

[0050] Examples 1-14 An embodiment of the liquid crystal polymer material, its preparation method, and its application described in this invention is shown in Table 1.

[0051] The method for preparing the liquid crystal polymer material includes the following steps: The components are mixed evenly, and then melt-extruded and granulated in a screw extruder to obtain the liquid crystal polymer material. In the examples, glass fiber is added in different side feed ports and the screw speed is different, as shown in Table 1.

[0052] During melt extrusion of the component, the screw extruder is a twin-screw extruder, the temperature zone of the twin-screw extruder is set to the melting point of the liquid crystal polymer used +10°C, and the screw length-to-diameter ratio is 48:1.

[0053] Comparative Examples 1-9 The only difference between each comparative example and the embodiment is the type and ratio of components, as shown in Table 2.

[0054] In the comparative preparation, glass fibers were added to different side feed ports, and the screw speed was different, as shown in Table 2.

[0055] In the components described in each embodiment and comparative example, The liquid crystal polymer 1 is Vicryst R8000 produced by Zhuhai Wantong, with a melting point of 280±10℃; The liquid crystal polymer 2 is Vicryst R8500 produced by Zhuhai Wantong, with a melting point of 335±10℃; The syndiotactic polystyrene 1 is a self-made product. Referring to CN112646066B, the preparation method is as follows: The dried reactor was evacuated and then repeatedly rinsed three times with nitrogen. At a polymerization temperature of 56°C, 3.8 L of toluene, 10.0 L of styrene, 9.0 L of a methylaluminoxane toluene solution (containing 15 mol of methylaluminoxane), and 2.0 L of a toluene solution of pentamethylcyclopentadienyl-(3,5-di(trifluoromethyl)-4-quinolinoxy)-dimethoxytitanium catalyst (containing 10 mmol of catalyst) were added sequentially. Timing was started, and after 2 hours of polymerization, acidified ethanol was added, and the mixture was stirred thoroughly. The polymer was filtered, dried under vacuum at 60°C, and weighed. The polymer was then refluxed in boiling acetone for 2 hours, filtered while hot, and a solid polymer was obtained. This solid polymer was dried under vacuum at 60°C to obtain the product, which had a weight-average molecular weight of 2.235 × 10⁻⁶. 5 Melting point 269.5℃; The syndiotactic polystyrene 2 is a self-made product. Referring to CN112646066B, the preparation method is as follows: The dried reactor was evacuated and then repeatedly rinsed three times with nitrogen. At a polymerization temperature of 70°C, 3.8 L of toluene, 10.0 L of styrene, 9.0 L of a methylaluminoxane toluene solution (containing 15.2 mol of methylaluminoxane), and 2.0 L of a pentamethylcyclopentadienyl-(3-methyl-4-quinolinoxy)-dimethoxytitanium catalyst toluene solution (containing 10 mmol of catalyst) were added sequentially. Timing was started, and after 2 hours of polymerization, acidified ethanol was added, and the mixture was stirred thoroughly. The polymer was filtered, dried under vacuum at 60°C, and weighed. The polymer was then refluxed in boiling acetone for 2 hours, filtered while hot, and a solid polymer was obtained. This solid polymer was dried under vacuum at 60°C to obtain the product, which had a weight-average molecular weight of 1.662 × 10⁻⁶. 5 Melting point 271℃; The syndiotactic polystyrene 3 is a self-made product. Referring to CN112646066B, the preparation method is as follows: The dried reactor was evacuated and then repeatedly rinsed three times with nitrogen. At a polymerization temperature of 70°C, 3.0 L of toluene, 10.0 L of styrene, 15.0 L of a methylaluminoxane toluene solution (containing 24.3 mol of methylaluminoxane), and 2 L of a pentamethylcyclopentadienyl-4-quinolinoxy-dimethoxytitanium catalyst toluene solution (containing 10 mmol of catalyst) were added sequentially. Timing was started, and after 2 hours of polymerization, acidified ethanol was added, and the mixture was stirred thoroughly. The polymer was filtered and dried under vacuum at 60°C, then weighed. The polymer was refluxed in boiling acetone for 2 hours, filtered while hot, and a solid polymer was obtained. This solid polymer was then dried under vacuum at 60°C to obtain the product, which had a weight-average molecular weight of 1.515 × 10⁻⁶. 5 Melting point 272℃; The glass fiber 1 is Owens Corning 923 product, with an initial average length of 3 mm and a diameter of 10 μm; The glass fiber 2 is Owens Corning 995 product, with an initial average length of 4 mm and a diameter of 10 μm; The glass fiber 3 is Owens Corning 272 product, with an initial average length of 4 mm and a diameter of 13 μm; The glass fiber 4 is an Owens Corning 415 product with an initial average length of 4 mm and a diameter of 14 μm. The talc powder is AH 51215 produced by Liaoning Aihai Talc Co., Ltd., with an average particle size of 4.5μm; The mica powder is SM-515 produced by Green Mining Co., Ltd., with an average particle size of 5μm.

[0056] Unless otherwise specified, all components and raw materials used in the embodiments and comparative examples of this invention are commercially available, and the same type of components and raw materials are used in each parallel experiment.

[0057] The average aspect ratio, length, and diameter of the retained glass fibers in the liquid crystal polymer material in Table 1 were confirmed as follows: First, the liquid crystal polymer material was calcined at 650℃ for 30 minutes to remove resin and retain inorganic matter. Glass fibers were then screened using ultrasonic treatment and uniformly dispersed in water. Two hundred intact glass fibers were selected using a two-dimensional microscope for observation and testing. The retained diameter and length of each glass fiber were measured (the diameter was measured at the middle position of the glass fiber). The aspect ratio was calculated based on the retained diameter and length. Then, the average aspect ratio of the 200 glass fibers was calculated, which is the average aspect ratio of the retained glass fibers in the liquid crystal polymer material. At the same time, the range of the retained diameter and length data for each product was recorded in the table (minimum value to maximum value).

[0058] Table 1 Table 2 To verify the performance of the liquid crystal polymer material described in this invention, the products prepared in each embodiment and comparative example were subjected to the following performance tests, the specific steps of which are as follows: (1) Shrinkage ratio test: 20 samples (sample size: 70mm long in the flow direction, 30mm wide in the vertical flow direction, and 1.5mm thick) were injected into the single-screw injection mold of each product. After 48 hours, the actual length of the sample in the vertical flow direction was measured by a two-dimensional measuring instrument. The ratio of the actual length to the theoretical length of the mold used is the shrinkage rate in the vertical flow direction. The average shrinkage rate in the vertical flow direction of the 20 samples is Y. The actual length of the sample in the flow direction was measured by a two-dimensional measuring instrument. The ratio of the actual length to the theoretical length of the mold used is the shrinkage rate in the flow direction. The average shrinkage rate in the flow direction of the 20 samples is X. The ratio of the shrinkage rate in the vertical flow direction (TD) to the shrinkage rate in the flow direction (MD) can be obtained by the formula α=Y / X.

[0059] (2) Processing uniformity test: Take the liquid crystal polymer composite material obtained by the twin-screw extruder and use a single-screw injection molding machine to inject five samples (sample mold dimensions: 127mm long along the flow direction, 12.7mm wide perpendicular to the flow direction, and 0.8mm thick) into a single-sided injection mold. Then cut 10mm samples at the sprue (near the gate) and 10mm samples at the end (far from the gate). Test the density according to ISO 1183-2004 standard. The average density near the gate is m, and the average density far from the gate is n. Then calculate the ratio β = n / m of the average density far from the gate n to the average density near the gate m. The closer the β value is to 1, the better the processing uniformity of the material. (3) Tensile strength test: The product was injection molded into a 115×10×4mm strip, and then the tensile strength test was performed at 23℃ and 2mm / min according to ISO 527-1-2012.

[0060] The test results are shown in Tables 3 and 4.

[0061] Table 3 Table 4 As can be seen from Tables 3 and 4, the liquid crystal polymer described in this invention, through the synergistic effect of synergistic polystyrene and glass fibers of a specific size, can effectively control the shrinkage difference in different directions during product processing. Tests show that the α value can be maintained within 10. Simultaneously, the product exhibits good processing uniformity, a β value above 0.90, and high tensile strength, reaching over 100 MPa, demonstrating excellent overall performance. This is mainly due to the use of liquid crystal polymer combined with synergistic polystyrene as the matrix resin, while introducing glass fibers as functional fillers. The spherulite growth of synergistic polystyrene and the specific size of the glass fibers interfere with the orientation differences of the liquid crystal polymer, resulting in a smaller shrinkage difference in all directions and, under high-speed processing, good processing uniformity and excellent mechanical properties.

[0062] In the product, the amount of syndiotactic polystyrene introduced is very critical. As can be seen from Examples 1-5 and Comparative Examples 2-3, the greater the amount of syndiotactic polystyrene introduced, the smaller the α value and the larger the β value, but the lower the tensile strength of the product. If too much is introduced, the product will be difficult to meet the mechanical properties required for use.

[0063] However, the molecular weight of syndiotactic polystyrene in the product cannot be too small. As can be seen from Examples 3, 9 and Comparative Example 1, if the molecular weight of syndiotactic polystyrene is too small, the degree of molecular chain entanglement is low. Not only does the difference in shrinkage rate in different directions increase and the processing uniformity decrease, but the mechanical strength also decreases, and the performance of the product cannot meet the standards.

[0064] Besides syndiotactic polystyrene, the functional filler glass fiber in the product is also crucial. If other common fillers are used instead, as shown in Comparative Examples 4 and 5, the product will not only fail to meet the tensile strength requirements, but may also cause processing uniformity problems. Furthermore, by using three-dimensionally distributed glass fiber, the product's retained aspect ratio can be controlled within a specific range of 10 to 16. Otherwise, as shown in Comparative Examples 6 to 9, the product cannot simultaneously achieve dimensional stability, processing uniformity, and mechanical strength. Further, as can be seen from Examples 3 and 10-13, when the average aspect ratio of the glass fiber retained in the liquid crystal polymer is preferably between 10.6 and 15, the α value can be smaller and the β value larger without significantly changing the tensile strength.

[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A liquid crystal polymer material, characterized in that, The components include the following parts by weight: 100 parts liquid crystal polymer, 10-100 parts syndiotactic polystyrene, 20-60 parts glass fiber; The weight-average molecular weight of the syndiotactic polystyrene is ≥160,000; The average aspect ratio of the glass fibers retained in the liquid crystal polymer material is 10~16.

2. The liquid crystal polymer material as described in claim 1, characterized in that, The liquid crystal polymer material comprises the following components in parts by weight: 100 parts liquid crystal polymer, 40-80 parts syndiotactic polystyrene, and 30-40 parts glass fiber.

3. The liquid crystal polymer material as described in claim 1, characterized in that, The melting point of the liquid crystal polymer is 270~350℃.

4. The liquid crystal polymer material as described in claim 1, characterized in that, The weight-average molecular weight of the syndiotactic polystyrene is 160,000 to 230,000.

5. The liquid crystal polymer material as described in claim 1, characterized in that, The average aspect ratio of the glass fiber retained in the liquid crystal polymer is 10.6 to 15.

6. The liquid crystal polymer material as described in claim 1, characterized in that, The glass fiber retains a length of 50-250 μm in the liquid crystal polymer and a diameter of 8-15 μm.

7. The liquid crystal polymer material as described in claim 1, characterized in that, The liquid crystal polymer material also includes 0.01 to 1 part of additives.

8. The method for preparing the liquid crystal polymer material according to any one of claims 1 to 7, characterized in that, Includes the following steps: The components are added to a screw extruder for melt extrusion and granulation to obtain the liquid crystal polymer material.

9. The method for preparing the liquid crystal polymer material as described in claim 8, characterized in that, The screw extruder is a twin-screw extruder. When the glass fiber is fed into the screw extruder, it is added from any one of the first, second, third, and fourth side feed ports. The screw speed of the twin-screw extruder is 300~400 r / min.

10. An optical device component, characterized in that, Includes the liquid crystal polymer material according to any one of claims 1 to 7.

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