A nylon composition, its preparation method and use

Abstract

The application discloses a nylon composition and a preparation method and application thereof, and belongs to the technical field of high polymer materials. The product is prepared by introducing a low-molecular-weight sPS resin into a PA66 resin and simultaneously compounding a maleic anhydride grafted polyphenyl ether resin as a compatible component. The product can effectively reduce a dielectric loss value, can be applied in a high-frequency scene, can improve forming stability and use performance of the product, has a low warping value, has good toughness, and has a good application effect.

Description

Technical Field

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

[0002] PA66 (polyhexamethylene adipamide) nylon material possesses excellent heat resistance and should theoretically have good application prospects in fields such as electronics, electrical engineering, and communications. However, to match the cost and rigidity requirements of product applications, PA66 nylon material generally needs to incorporate glass fiber as a reinforcing filler. However, because PA66 nylon is a crystalline material, it undergoes some volume shrinkage after processing due to the release of internal stress. Combined with the anisotropic nature of glass fiber, this glass fiber reinforced nylon product is prone to warping. Furthermore, glass fiber reinforced PA66 nylon material has high dielectric loss characteristics, making it currently unsuitable for effective application in high-frequency scenarios. Summary of the Invention

[0003] Based on the deficiencies of existing technologies, the present invention aims to provide a nylon composition that, by introducing low molecular weight sPS resin into PA66 resin and compounding maleic anhydride-grafted polyphenylene ether resin as a compatible component, can not only effectively reduce the dielectric loss value of the product, making it applicable in high-frequency scenarios, but also improve the molding stability and performance of the product. The product has low warpage, good toughness, and good application effect.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A nylon composition comprising the following components in parts by weight: 28-50 parts PA66 resin, 10-32 parts SPS (syndiotactic polystyrene) resin, 18-32 parts glass fiber, 1.5-8.5 parts compatibilizer, and 0.5-1.5 parts lubricant; The weight-average molecular weight of the sPS resin is ≤200,000; The compatibilizer comprises maleic anhydride-grafted polyphenylene ether resin, wherein the maleic anhydride grafting rate of the maleic anhydride-grafted polyphenylene ether resin is ≥0.5 wt%. The lubricant includes wax-based lubricants and salt-based lubricants.

[0005] Existing glass fiber reinforced PA66 nylon composite materials, due to the combined effect of resin and glass fiber, cannot achieve good processing stability and are prone to warping. Furthermore, these products have high dielectric loss values, thus limiting their effective application in fields requiring high flatness and dielectric loss, such as electronics and communications. Therefore, in this invention, to balance low dielectric loss and low warping, the inventors introduced a compounded SPS resin into the glass fiber reinforced PA66 resin system. This component itself has a high dielectric constant, thus exhibiting good dielectric stability when combined with PA... The compounding of PA66 resin effectively reduces the dielectric loss of the product. Furthermore, at the specified compounding ratio, the introduction of a compatibilizer, maleic anhydride-grafted polyphenylene ether resin, allows the grafted maleic anhydride to enable a synergistic effect between PA66 and SPS resins. Additionally, it effectively matches the polarity of the two resins, reducing interfacial tension between different resins and between organic resins and glass fibers, thus weakening the anisotropic effect of the glass fibers. This effectively improves the overall molding stability of the product, significantly suppressing the post-shrinkage effect of PA66 resin after molding, ultimately achieving low warpage. However, the type and grafting rate of the compatibilizer have a significant impact on the product's performance. If the grafting rate is too low, it cannot effectively provide compatibilization, and the product cannot achieve low warpage. Conversely, if other types of compatibilizers are used, such as maleic anhydride-grafted EVA, they cannot simultaneously match the polarity of PA66 and SPS resins, also failing to achieve the desired effect. In addition, the type of lubricant also affects the warpage of the final molded product. Combining wax-based and salt-based lubricants can facilitate the movement of the molecular chains of SPS resin, reduce internal stress during the molding process, and also play a partial compatibility role. Together with maleic anhydride-grafted polyphenylene ether resin, they can improve the dispersibility and compatibility of the components, resulting in better warpage of the product.

[0006] On the other hand, even if a suitable proportion of maleic anhydride-grafted polyphenylene ether resin is introduced as a compatibilizer, if the weight-average molecular weight of the sPS resin is too high and the degree of intermolecular entanglement is too high, the component still cannot achieve compatibility and uniform dispersion with PA66 resin and glass fiber, and the product may still exhibit high warping defects. Therefore, the product described in this invention needs to be prepared using sPS resin with a weight-average molecular weight not exceeding 200,000 as a component. Furthermore, the mixing ratio of sPS resin and PA66 resin cannot be arbitrary; otherwise, it may affect the product's performance, resulting in insufficient toughness and low flexibility. Therefore, the formulation ratio specified in this invention must be adopted.

[0007] In some embodiments, the PA66 resin is in the range of 28 parts, 30 parts, 32 parts, 35 parts, 40 parts, 45 parts, 48 ​​parts, and 50 parts by weight, or any two of these values; the sPS resin is in the range of 10 parts, 12 parts, 15 parts, 18 parts, 20 parts, 22 parts, 25 parts, 30 parts, and 32 parts by weight, or any two of these values; the glass fiber is in the range of 18 parts, 20 parts, 25 parts, 28 parts, 30 parts, and 32 parts by weight, or any two of these values; the compatibilizer is in the range of 1.5 parts, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, and 8.5 parts by weight, or any two of these values; and the lubricant is in the range of 0.5 parts, 0.6 parts, 0.7 parts, 1 part, 1.4 parts, and 1.5 parts by weight, or any two of these values.

[0008] More preferably, the nylon composition comprises the following components in parts by weight: 30-48 parts PA66 resin, 12-30 parts SPS resin, 20-30 parts glass fiber, 2-8 parts compatibilizer, and 0.7-1.4 parts lubricant.

[0009] More preferably, the PA66 resin has a mass content of ≥30wt% in the nylon composition.

[0010] Preferably, the viscosity of the PA66 resin at 25°C is 2~2.8 according to ISO 307-2007 (test solvent: 96% concentrated hydrochloric acid, test concentration: 1%).

[0011] More preferably, the relative viscosity of the PA66 resin at 25°C is one or any two of the following: 2, 2.2, 2.4, 2.6, and 2.8.

[0012] More preferably, the viscosity of the PA66 resin at 25°C is 2.1~2.7 according to ISO 307-2007. In the technical solution of this invention, the viscosity of PA66 resin is not specifically limited. Those skilled in the art can select a suitable viscosity of PA66 resin to construct the matrix resin according to the rigidity and toughness requirements of the product. As long as it does not affect the dielectric properties and warpage of the product, it is not limited.

[0013] In some embodiments, the mass ratio of PA66 resin to sPS resin is ≥1.

[0014] Preferably, the mass ratio of PA66 resin to sPS resin is 1 to 4; More preferably, the mass ratio of PA66 resin to sPS resin is 1.5 to 3.5.

[0015] More preferably, the mass ratio of PA66 resin to sPS resin is 2 to 3.

[0016] When a low molecular weight SPS resin is blended with the glass fiber reinforced PA66 resin described in this application, the dielectric loss value of the product will be effectively improved. As the proportion of this component in the matrix resin gradually increases, the dielectric loss value of the product continuously decreases, and the warpage and deflection of the product also change. When the proportion of the two resins is preferably within the above range, the product can achieve lower dielectric loss, warpage and deflection.

[0017] Preferably, the weight-average molecular weight of the sPS resin is 70,000 to 200,000, in g / mol.

[0018] More preferably, the weight-average molecular weight of the sPS resin is 71,000 to 190,000.

[0019] More preferably, the melting point of the sPS resin is 265~275℃.

[0020] It should be noted that the method for determining the weight-average molecular weight 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).

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

[0022] 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 1~3h. Then acidified ethanol is added and stirred and mixed. After filtration, the resulting solid is dried and purified to obtain the syndiotactic polystyrene.

[0023] Preferably, the molar amount of methylaluminoxane in the methylaluminoxane toluene solution is 10~30 mol.

[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 amount of catalyst in the catalyst solution is 2~20 mmol.

[0026] More preferably, the volume ratio of the toluene, styrene, methylaluminoxane toluene solution and the catalyst solution is (1~3):(4~6):(4~8):1.

[0027] Preferably, the grafting rate of the maleic anhydride-grafted polyphenylene ether resin can be confirmed by, but is not limited to, the following methods: The maleic anhydride grafting rate of the maleic anhydride-grafted polyphenylene ether (MAH-g-PPE) is determined by acid-base titration. Specifically, acetone is used as the solvent, and unreacted maleic anhydride in MAH-g-PPE is removed by Soxhlet extraction. Then, MAH-g-PPE is dissolved in an organic solvent (such as xylene). Then, an excess of strong base (such as sodium hydroxide) is added to hydrolyze the anhydride groups. Then, the unreacted strong base is back-titrated with a strong acid (such as hydrochloric acid). Finally, the maleic anhydride grafting rate of MAH-g-PPE is calculated based on the titration results.

[0028] In some embodiments, the maleic anhydride grafting rate of the maleic anhydride-grafted polyphenylene ether resin is 0.5 to 1.5 wt%, and may further be a range of one or any two of 0.5 wt%, 0.6 wt%, 0.8 wt%, 1 wt%, 1.2 wt%, and 1.5 wt%.

[0029] More preferably, the maleic anhydride grafting rate of the maleic anhydride-grafted polyphenylene ether resin is 0.8~1.2wt%.

[0030] When the grafting rate of maleic anhydride-grafted polyphenylene ether resin is preferably within the above range, the compatibility between PA66 resin and sPS resin, and between organic resin and glass fiber, is higher, and the product can achieve better overall performance.

[0031] Preferably, the maleic anhydride-grafted polyphenylene ether resin can be a commercially available product or a self-made product. The specific preparation method is to add PPE resin and maleic anhydride in a certain proportion to a twin-screw extruder, add an initiator, and mix at 260~280℃ to obtain maleic anhydride-grafted polyphenylene ether resins with different grafting rates.

[0032] More preferably, the total amount of maleic anhydride added to the polyphenylene ether resin and maleic anhydride is 0.5 to 1.8 wt% by mass.

[0033] More preferably, the initiator is at least one of 1,4-di-tert-butylperoxyisopropylbenzene, diisopropylbenzene peroxide, benzoyl peroxide, and di-tert-butyl peroxide.

[0034] More preferably, the intrinsic viscosity of the polyphenylene ether resin, tested according to ISO 1628 / 1-2021, is 30~55 cm⁻¹. 3 / g (test solvent phenol / tetrachloroethane, volume ratio 50:50).

[0035] Preferably, the glass fiber has an average length of 3-4.5 mm and an average diameter of 9-13 μm.

[0036] More preferably, the glass fiber is alkali-free glass fiber.

[0037] In the technical solution of this invention, there are no special restrictions on the selection of glass fiber. Those skilled in the art can select glass fiber of different sizes as reinforcing filler according to the mechanical performance requirements of the actual product. Furthermore, the use of alkali-free glass fiber can effectively improve the hydrolysis resistance of the product and extend its service life. However, those skilled in the art can also use other types of glass fiber, as long as it does not affect the dielectric properties and low warpage of the product.

[0038] Preferably, the nylon composition further includes 0.1 to 2 parts of antioxidant.

[0039] More preferably, the antioxidant includes at least one of hindered phenolic antioxidants, phosphite antioxidants, and hindered amine antioxidants.

[0040] Preferably, the components of the nylon composition may include, but are not limited to, antistatic agents, flame retardants, etc. Based on the processing or actual use needs of those skilled in the art, other types of functional additives may be added without affecting the expected performance of the product. For example, the above-mentioned additives can improve the antistatic ability and flame retardancy of the product without affecting the characteristic performance of the product. That is, the description of the product components in the technical solution of the present invention is not a limitation on the types of components.

[0041] Preferably, the wax lubricant includes at least one of ethylene-propylene copolymer wax, ethylene-vinyl acetate wax, and polyethylene wax.

[0042] Preferably, the salt lubricant includes at least one of long-chain linear saturated lignite sodium salt, borate lubricant, imidazole salt lubricant, and quaternary ammonium salt lubricant.

[0043] Preferably, the mass ratio of the wax lubricant to the salt lubricant is (1:9) to (9:1). More preferably, the mass ratio of the wax lubricant to the salt lubricant is (4:6) to (6:4).

[0044] Experiments have shown that when the two lubricants are further optimized to the above ratio, the effect on alleviating internal stress and improving synergistic compatibility of components is better, resulting in superior product performance.

[0045] Another object of the present invention is to provide a method for preparing the nylon composition, comprising the following steps: The components are added to a screw extruder for melt extrusion and granulation to obtain the nylon composition.

[0046] Preferably, the temperature range of the screw extruder is 270~290℃, the screw speed is 300~500rpm, and the length-to-diameter ratio is (36~48):1.

[0047] Another object of the present invention is to provide the use of the nylon composition in the manufacture of electronic devices.

[0048] Preferably, the electronic device includes a connector, a switch, and a support frame.

[0049] Another object of the present invention is to provide an electronic device comprising the nylon composition described herein.

[0050] Due to the synergistic effect of key components, the nylon composition of this invention can effectively reduce the dielectric loss value of the product while retaining the glass fiber reinforcement system, making it applicable to high-frequency scenarios in electronic devices in the field of communication. At the same time, the warpage of the product after molding is significantly reduced, and the molding is stable, which can effectively replace existing glass fiber reinforced nylon materials.

[0051] The beneficial effects of this invention are that it provides a nylon composition by introducing low-flow sPS resin into PA66 resin and compounding maleic anhydride-grafted polyphenylene ether resin as a compatible component. This not only effectively reduces the dielectric loss value of the product, making it applicable in high-frequency scenarios, but also improves the molding stability and performance of the product. The product has a low warpage value while maintaining good toughness and good application effect. Detailed Implementation

[0052] 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.

[0053] Examples 1-14 Examples of the nylon composition of the present invention are shown in Table 1.

[0054] The method for preparing the nylon composition includes the following steps: The components are mixed evenly, and then melt-extruded and granulated in a twin-screw extruder to obtain the nylon composition.

[0055] During melt extrusion of the component, the temperature range of the screw extruder is set to 270~290℃, the screw speed is 400rpm, and the length-to-diameter ratio is 40:1.

[0056] Comparative Examples 1-10 The only difference between each comparative example and Example 1 is the type and ratio of components, as shown in Table 2.

[0057] In the components described in each embodiment and comparative example, The PA66 resin 1 is PA66 U2501 manufactured by Invista, with a viscosity of 2.1 at 25°C; The PA66 resin 2 is PA66 U4800 manufactured by Invista, with a viscosity of 2.7 at 25°C; The sPS resin 1 is a self-made product. Referring to CN112646066B, the preparation method is as follows: The dried polymerization flask was evacuated and rinsed three times with nitrogen. At a polymerization temperature of 56°C, 3.8 L of toluene, 10 L of styrene, 9 L of methylaluminoxane toluene solution (containing 15 mol of methylaluminoxane), and 2 L of pentamethylcyclopentadienyl-4-quinolinoxy-dimethoxytitanium catalyst toluene solution (containing 10 mmol of catalyst) were added sequentially. Timing was started, and after 2 hours of polymerization, the reaction mixture was carefully poured into a beaker, acidified ethanol was added, and the mixture was thoroughly stirred and mixed. The mixture was filtered to obtain the polymer, and the filter cake was vacuum dried 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 then vacuum dried at 60°C to obtain the product, which had a weight-average molecular weight of 7.170 × 10⁻⁶. 4 Melting point 272℃; The sPS resin 2 is a self-made product. Referring to CN112646066B, the preparation method is as follows: After evacuating the dried polymerization flask, it was repeatedly rinsed three times with nitrogen. At a polymerization temperature of 85°C, 3.8 L of toluene, 10 L of styrene, 9 L of methylaluminoxane toluene solution (containing 15 mol of methylaluminoxane), and 2 L of pentamethylcyclopentadienyl-(3,5-di(trifluoromethyl)-4-quinolinoxy)-dimethoxytitanium catalyst toluene solution (containing 10 mmol of catalyst) were added sequentially. Timing was started, and after 2 hours of polymerization, the reaction mixture was carefully poured into a beaker, acidified ethanol was added, and the mixture was thoroughly stirred and mixed. The mixture was filtered to obtain the polymer, and the filter cake was vacuum dried 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 then vacuum dried at 60°C to obtain the product, which had a weight-average molecular weight of 1.895 × 10⁻⁶. 5 Melting point 271℃; The sPS resin 3 is a self-made product. Referring to CN112646066B, the preparation method is as follows: The dried polymerization flask was evacuated and rinsed three times with nitrogen. At a polymerization temperature of 54°C, 3.8 L of toluene, 10 L of styrene, 9 L of methylaluminoxane toluene solution (containing 15 mol of methylaluminoxane), and 2 L of pentamethylcyclopentadienyl-(3,5-di(trifluoromethyl)-4-quinolinoxy)-dimethoxytitanium catalyst toluene solution (containing 10 mmol of catalyst) were added sequentially. Timing was started, and after 2 hours of polymerization, the reaction mixture was carefully poured into a beaker, acidified ethanol was added, and the mixture was thoroughly stirred and mixed. The mixture was filtered to obtain the polymer, and the filter cake was vacuum dried at 60°C and weighed. The polymer was then refluxed in boiling acetone for 2 hours, filtered while hot, and the solid polymer was obtained. The solid polymer was then vacuum dried at 60°C to obtain the product, which had a weight-average molecular weight of 2.241 × 10⁻⁶. 5 Melting point 269.5℃; The compatibilizers 1-5 are self-made maleic anhydride-grafted polyphenylene ether resins, each with a different grafting rate. The preparation method involves adding polyphenylene ether resin, commercially available maleic anhydride (maleic anhydride), and an appropriate amount of initiator 1,4-di-tert-butylperoxyisopropylbenzene to a twin-screw extruder. The mixture is then kneaded under controlled feeding ratios of polyphenylene ether resin and commercially available maleic anhydride (maleic anhydride) to obtain maleic anhydride-grafted polyphenylene ether resins with different grafting rates. The extrusion temperatures in zones 1 to 10 of the twin-screw extruder are 260, 260, 270, 280, 250, 250, 250, 250, 260, and 280°C, respectively. The total amount of maleic anhydride added to the polyphenylene ether resin and maleic anhydride contains 0.2-1.8 wt% maleic anhydride; as the content increases, the grafting rate of the final product also increases. The polyphenylene oxide resin shown is PPE LXN040 produced by Nantong Xingchen, with an intrinsic viscosity of 45 cm⁻¹.3 / g. ; The grafting rate of compatibilizer 1 (maleic anhydride) was 0.5 wt%. The grafting rate of compatibilizer 2 (maleic anhydride) was 0.8 wt%. The grafting rate of compatibilizer 3, maleic anhydride, was 1.2 wt%. The grafting rate of compatibilizer 4 (maleic anhydride) was 1.5 wt%. The grafting rate of compatibilizer 5 (maleic anhydride) was 0.1 wt%. The compatibilizer 6 is KT-26 produced by Shenyang Ketong, and the maleic anhydride grafting rate of EVA is 0.9%. The glass fiber 1 is ECS10-03-568H produced by Jushi, with an average length of 3mm and an average diameter of 10μm; The glass fiber 2 is ECS11-4.5-560A glass fiber produced by Jushi, with an average length of 4.5 mm and an average diameter of 11 μm; The antioxidant is commercially available hindered phenolic antioxidant 1098, N,N'-hexamethylenebis(3,5-di-tert-butyl-4-hydroxyphenylpropionamide); The lubricant 1 is Clariant's NAV101, a salt lubricant, long-chain linear saturated sodium lignite salt; The lubricant 2 is Honeywell AC540A, a wax-based lubricant, an ethylene-acrylic acid copolymer wax.

[0058] The lubricant 3 is GT-300, an organosilicon lubricant and silicone masterbatch, produced by Zhejiang Jiahua Fine Chemicals.

[0059] Unless otherwise specified, all raw materials used in the embodiments and comparative examples of this invention are commercially available. The results are shown in Table 1. Table 1 Table 2 To verify the performance of the nylon composition described in this invention, the products prepared in each embodiment and comparative example were subjected to the following performance tests, with the specific steps as follows: (1) Warpage test: The products of each embodiment and comparative example were pre-dried at 120℃ for 4 hours, and then injection molded into 100mm×100mm×0.8mm test square plates at 280~290℃. The warpage value was measured. The test method was as follows: the square plate was placed on a plane, and one corner of the square plate was pressed down with a weight of the same mass. The height of the warpage from the opposite corner to the plane was measured, and the highest value of the warpage from the opposite corner was taken as the warpage value. (2) Dielectric loss value test: The products of each embodiment and comparative example were dried at 120°C for 4 hours in advance, and then a test square plate with dimensions of 100mm×100mm×0.8mm was injection molded at 280~290°C. The dielectric loss value was tested at 10GHz according to IEC 60250:2020 standard, with a test temperature of 23°C and 50%RH humidity. (3) Deflection test: The products of each embodiment and comparative example were dried at 120°C for 4 hours, and then ISO test strips were injection molded at 280~290°C. The deflection test was carried out according to ISO 178-2019 standard, and the maximum distance from the initial point within the test range was recorded as the result.

[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 nylon composition of the present invention has ideal processing performance. The warpage value of the products after injection molding in each embodiment does not exceed 8 mm, and the dielectric loss value does not exceed 0.008. At the same time, the material can maintain a certain toughness, and the deflection can reach more than 5.5 mm. This indicates that the product has low dielectric loss characteristics, good processing stability and performance, and excellent comprehensive performance, making it very suitable for electronic device materials.

[0062] In contrast, the product described in Comparative Example 1 did not incorporate sPS resin. This product not only had a high dielectric loss value but also a high warpage. This indicates that the introduction of sPS resin into the product system of this invention can simultaneously improve the dielectric properties and molding stability of the product. However, the amount of this resin introduced cannot be too much; otherwise, as shown in Comparative Example 2, the toughness of the product will decrease significantly, and the product's usability will also decrease significantly. In addition, the molecular weight of sPS resin cannot be too large; otherwise, as shown in Comparative Example 3, after introducing sPS resin, compared with the product in Comparative Example 1, not only will the warpage not be effectively reduced, but the deflection will also decrease significantly.

[0063] In addition to the introduction of SPS resin, the type of compatibilizer used in the product described in this invention is also crucial. Besides requiring a specific matching maleic anhydride-grafted polyphenylene ether resin, the grafting rate of maleic anhydride must be 0.5% or higher; otherwise, sufficient compatibility will be difficult to achieve, thus affecting product performance. As shown in Comparative Examples 4, 5, 1, and 9-11, Comparative Example 5, which uses maleic anhydride grafted onto EVA with a similar grafting rate, exhibits higher warpage and dielectric loss values, and also poorer deflection. In contrast, Comparative Example 4, with a lower grafting rate, has a lower dielectric loss value, but a warpage of 11 mm and a deflection of only 3.9 mm. As the maleic anhydride grafting rate of the grafted polyphenylene ether resin gradually increases, the processing warpage of the product gradually decreases, and the deflection gradually increases. Furthermore, when the grafting rate is between 0.8% and 1.2%, the product performance reaches an even better level. Meanwhile, it can be seen from Examples 1, 5-6 and Comparative Example 6 that when the amount of compatibilizer added is too small, the performance of the product in all aspects is poor. As the amount added increases, the compatibilizing effect of the compatibilizer gradually emerges.

[0064] On the other hand, the use of lubricants in the product is also a key guarantee for product performance. In the product of this invention, since sPS resin is introduced, wax-based lubricants and salt-based lubricants need to be used in combination to take into account both internal and external lubrication effects. This is beneficial to the molecular chain movement of sPS resin and reduces internal stress during the molding process. If one of them is missing, as shown in Comparative Examples 7 and 8, the product cannot maintain sufficient molding stability and has high warpage. If other types of lubricants are used in combination, the product also cannot achieve the effect of low warpage value, as shown in Comparative Examples 9 and 10.

[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 nylon composition, characterized in that, The components include the following parts by weight: 28-50 parts PA66 resin, 10-32 parts SPS resin, 18-32 parts glass fiber, 1.5-8.5 parts compatibilizer, and 0.5-1.5 parts lubricant; The weight-average molecular weight of the sPS resin is ≤200,000; The compatibilizer comprises maleic anhydride-grafted polyphenylene ether resin, wherein the maleic anhydride grafting rate of the maleic anhydride-grafted polyphenylene ether resin is ≥0.5wt%. The lubricant includes wax-based lubricants and salt-based lubricants.

2. The nylon composition according to claim 1, characterized in that, The relative viscosity of the PA66 resin at 25°C is 2~2.

8.

3. The nylon composition according to claim 1, characterized in that, The mass ratio of PA66 resin to sPS resin is ≥1; the mass ratio of PA66 resin to sPS resin is 1~4.

4. The nylon composition according to claim 1, characterized in that, The melt flow rate of the sPS resin at 300℃ and 1.2kg load is 10~40g / 10min.

5. The nylon composition according to claim 1, characterized in that, The maleic anhydride grafting rate of the maleic anhydride-grafted polyphenylene ether resin is 0.5~1.5wt%.

6. The nylon composition according to claim 1, characterized in that, The glass fibers have an average length of 3-4.5 mm and an average diameter of 9-13 μm.

7. The nylon composition according to claim 1, characterized in that, The nylon composition also includes 0.1 to 2 parts of antioxidant.

8. A method for preparing the nylon composition 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 nylon composition.

9. The use of the nylon composition according to any one of claims 1 to 7 in the manufacture of electronic devices.

10. An electronic device, characterized in that, Includes the nylon composition according to any one of claims 1 to 7.

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