Laser high-transmittance reinforced PA66 material and preparation method thereof

Abstract

The application relates to the technical field of engineering plastics, and specifically discloses a laser high-transmittance reinforced PA66 material and a preparation method thereof, the laser high-transmittance reinforced PA66 material contains the following raw materials in parts by weight: PA66 resin 43-56 parts, PA6I / 6T resin 10-20 parts, flat glass fiber 30-35 parts, transmittance modifier 1-2 parts, flow agent 0.2-0.3 parts, lubricant 0.1-0.5 parts and antioxidant 0.1-0.3 parts; the preparation method is as follows: S1, the PA66 resin, the PA6I / 6T resin, the flat glass fiber, the transmittance modifier, the flow agent, the lubricant and the antioxidant are weighed and uniformly mixed and stirred to obtain a mixture; S2, the mixture is melt-extruded to obtain a finished product; the finished product has the advantages of high laser transmittance and low warpage.

Description

Technical Field

[0001] This application relates to the technical field of engineering plastics, and more specifically, to a laser-enhanced high-transparency PA66 material and its preparation method. Background Technology

[0002] PA66 material generally refers to polyhexamethylene adipamide, a thermoplastic resin made by the condensation polymerization of adipic acid and hexamethylenediamine. As a semi-crystalline polymer, PA66 has a grain size larger than the laser wavelength, which causes strong scattering of the laser within the material, limiting its use in applications requiring high light transmittance, such as laser welding. In the injection molding process, traditional PA66 is prone to warping and deformation of the product due to uneven crystallization or differences in shrinkage, affecting dimensional stability.

[0003] Therefore, how to prepare a new PA66 material that has the advantages of high laser transmittance, low warpage, and good dimensional stability is an urgent problem to be solved. Summary of the Invention

[0004] In order to prepare a new PA66 material with the advantages of high laser transmittance, low warpage and good dimensional stability, this application provides a laser high transmittance enhanced PA66 material and its preparation method.

[0005] In a first aspect, this application provides a laser-enhanced high-transmittance PA66 material, employing the following technical solution: A laser-enhanced high-transparency PA66 material comprises the following raw materials in parts by weight: 43-56 parts of PA66 resin, 10-20 parts of PA6I / 6T resin, 30-35 parts of flat glass fiber, 1-2 parts of antireflective modifier, 0.2-0.3 parts of flow agent, 0.1-0.5 parts of lubricant, and 0.1-0.3 parts of antioxidant.

[0006] By adopting the above technical solution, PA66 resin and PA6I / 6T resin are combined. The isophthalic acid unit (PA6I) in PA6I / 6T resin introduces a rigid aromatic ring, which can disrupt the regularity of PA66 molecular chain, reduce crystallinity, suppress light scattering and improve transmittance. Furthermore, the high molecular weight segments of PA6I / 6T resin act as heterogeneous nucleating agents, refining the grain size. The amorphous structure of PA6I / 6T hinders the formation of cross-crystals, reduces orientation, makes the microstructure more uniform, reduces scattering centers, further suppresses light scattering and improves transmittance.

[0007] Flat glass fibers and antireflective modifiers are added to PA66 resin. The sheet-like structure of flat glass fibers scatters laser light less than that of traditional round glass fibers. The rectangular cross-section of flat glass fibers makes them more orderly arranged in the PA66 matrix, reducing interfacial discontinuities and thus lowering the light scattering center. Flat glass fibers have a larger specific surface area, which allows for more uniform contact and transmission of light. Combined with the light transmittance-enhancing effect of antireflective modifiers, the light transmittance and low scattering effect of the finished material are further improved.

[0008] The combination of PA66 resin, PA6I / 6T resin, and flat glass fiber can form a structurally stable three-dimensional network that suppresses warping. The flat glass fiber, with its unique shape and high specific surface area, can be uniformly dispersed in PA66 resin, reducing warping caused by uneven fiber orientation. Combined with the amorphous characteristics of PA6I / 6T resin, it can better release internal stress during processing, reducing warping and giving the finished material the advantage of low warping.

[0009] PA6I / 6T resin has lower hygroscopicity than traditional PA6 and PA66, reducing dimensional changes caused by moisture absorption. PA6I / 6T resin has a heat resistance temperature of up to 260℃, making it suitable for continuous high-temperature working environments, thereby improving the dimensional stability of the material. Combined with the mechanical interlocking of flat glass fibers with the matrix, it improves the bonding strength between the flat glass fibers and the interface, reduces interface stress concentration and microcracks, and further ensures the dimensional stability of the finished product.

[0010] Preferably, the flat glass fiber is prepared by plasma etching of flat glass fiber filaments, impregnation with silane coupling agent KH-550, treatment with chitosan composite solution, and then heating treatment.

[0011] By adopting the above technical solution, the surface area of ​​the flat glass fiber filaments increases after plasma etching, contaminants are removed, and light scattering caused by impurities is reduced. Furthermore, the nanoscale regular grooves created by plasma etching can further reduce light scattering. After etching, the hydroxyl content on the surface of the flat glass fiber filaments increases, and the hydroxyl groups in the etched pits on the surface of the flat glass fiber filaments can easily connect with the silane coupling agent KH-550, improving the surface flatness of the flat glass fiber filaments, thereby increasing light transmittance and reducing light scattering. In addition, the surface of the flat glass fiber filaments contains free amino groups of the silane coupling agent KH-550, which are hydrogen-bonded with the amino and carboxyl groups in chitosan. The surface of the flat glass fiber filaments is loaded with chitosan, which carries a positive charge. This allows the flat glass fiber filaments to be arranged in an orderly parallel orientation in PA66, which can suppress the multiple scattering effect and thus reduce light scattering.

[0012] The silane coupling agent KH-550 on the surface of flat glass fiber can improve the compatibility and bonding effect between flat glass fiber and PA66. Combined with the high strength and good stability of flat glass fiber, it can improve the dimensional stability of the finished material. Furthermore, the cross-linking network of silane coupling agent KH-550 and chitosan resists stress, thereby further controlling warpage and improving dimensional stability.

[0013] Preferably, the chitosan composite solution is prepared from a chitosan acetic acid solution and carboxyl-modified EPDM-g-MAH in a mass ratio of 1:0.1-0.2.

[0014] By adopting the above technical solution, EPDM-g-MAH particles are insoluble in acetic acid aqueous solution. After loading flat glass fiber filaments with silane coupling agent KH-550, the carboxyl groups in the carboxyl-modified EPDM-g-MAH can be attracted and linked to the free amino groups on the surface of the flat glass fiber filaments. They can be distributed and filled in the nano-pits etched by plasma etching. With subsequent heating treatment, EPDM-g-MAH is thermally melted and flowed on the surface of the flat glass fiber. The thermally melted and flowed EPDM-g-MAH can fill the pits of the flat glass fiber, improving the flatness of the flat glass fiber and thus reducing the light scattering of PA66. Furthermore, in the subsequent PA66 melt extrusion process, EPDM-g-MAH distributed in the pits and all positions on the plane of the flat glass fiber can improve the compatibility and bonding effect between the flat glass fiber and PA66. Combined with silane coupling agent KH-550, the compatibility and bonding are further guaranteed, thereby reducing warpage while ensuring dimensional stability and strength.

[0015] Preferably, the antireflective modifier is prepared from modified graphene microsheets and modified polyphenylene sulfide microparticles in a mass ratio of 1:0.5-1.

[0016] By adopting the above technical solution, the ultrathin sheet structure of graphene microsheets can not only guide light to propagate along the direction parallel to the sheet, reducing random scattering, but also form a continuous nanophase network, reducing the number of interfaces in the light propagation particle size, smoothing the refractive index gradient of the interface layer, reducing Mie scattering, and thus reducing light scattering. Furthermore, graphene microsheets can act as nucleating agents, inducing PA66 to form finer and more uniform grains, reducing grain boundary density, controlling PA66 chain segment movement, and inhibiting the growth of large-sized spherulites, thereby reducing light scattering.

[0017] The combination of modified graphene microsheets and modified polyphenylene sulfide (PPS) microparticles, with the refractive index difference between PPS and PA66 falling between the refractive index differences of graphene microsheets and PA66, controls the limitation of the refractive index gradient, which can weaken the Mie scattering intensity of light at the interface. PPS microparticles can also act as heterogeneous nucleating agents, reducing the nucleation barrier of PA66 and promoting the simultaneous generation of more crystal nuclei. This refines the grain size while suppressing light scattering caused by large-sized spherulites.

[0018] Preferably, the modified graphene microsheets are prepared from nano-graphene microsheets and triethylene adipate in a mass ratio of 1:0.1-0.18.

[0019] By adopting the above technical solution, triethylene adipate undergoes hydrogen bonding or esterification reactions with oxygen-containing functional groups on the surface of graphene nanosheets via hydroxyl groups, forming a surface-loaded structure. This structure constructs a continuous refractive index gradient transition region between graphene and PA66, buffering the refractive index difference between graphene nanosheets and PA66, resulting in a smoother refractive index transition and significantly reducing Mie scattering intensity. Furthermore, triethylene adipate can form hydrogen bonds with the amide groups in the PA66 molecular chain, enhancing the melt-blending compatibility of graphene nanosheets and PA66 and reducing light scattering. At the same time, limiting the amount of triethylene adipate added facilitates the formation of parallel orientations of the graphene nanosheets modified with triethylene adipate, forming a "nanowaveguide"-like structure. This facilitates light propagation parallel to the sheet direction, reducing random scattering events. The higher structural density avoids Rayleigh scattering caused by voids or debonding, further improving the optical continuity of the material. As a result, the finished material has the advantages of high transmittance and low scattering.

[0020] Preferably, the average particle size of the graphene nanosheets is 80-200 nm, and the average particle size of the polyphenylene sulfide microparticles is 1-3 μm.

[0021] By adopting the above technical solution and limiting the particle size of the raw materials, micron-sized polyphenylene sulfide microparticles are combined with nano-sized graphene microsheets, so that the finished material has the advantages of high laser transmittance and low light scattering.

[0022] Preferably, the flow agent is a hyperbranched resin.

[0023] By adopting the above technical solutions, fluidity is improved, the uniformity of raw material mixing is increased, and the fluidity of the melt is guaranteed, thereby ensuring the quality of the finished product.

[0024] Preferably, the lubricant is composed of erucamide and microcrystalline wax in a mass ratio of 1:0.5-1.

[0025] By adopting the above technical solution, erucamide is used as an internal lubricant in combination with microcrystalline wax as an external lubricant, which reduces friction, ensures the lubrication effect of the melt, and further guarantees the quality of the finished product.

[0026] Preferably, the antioxidant is composed of antioxidant 9228 and antioxidant 1098 in a mass ratio of 1:0.2-0.5.

[0027] By adopting the above technical solutions, the antioxidant effect of the finished materials can be improved.

[0028] Secondly, this application provides a method for preparing laser-enhanced high-transmittance PA66 material, employing the following technical solution: A method for preparing laser-enhanced high-transmittance PA66 material includes the following steps: S1. Weigh PA66 resin, PA6I / 6T resin, flat glass fiber, antireflective modifier, flow agent, lubricant, and antioxidant, mix and stir evenly to obtain a mixture; S2. The mixture is melt-extruded to obtain the finished product.

[0029] By adopting the above technical solution, the finished product has the advantages of high laser transmittance, low warpage, and good dimensional stability.

[0030] In summary, this application has the following beneficial effects: 1. The combination of PA66 resin and PA6I / 6T resin introduces a rigid aromatic ring into the isophthalic acid unit (PA6I) in PA6I / 6T resin, which can disrupt the regularity of PA66 molecular chain, reduce crystallinity, suppress light scattering and improve transmittance. In addition, the high molecular weight segments of PA6I resin and PA6T resin act as heterogeneous nucleating agents to refine the grain size. The amorphous structure of PA6I / 6T hinders the formation of cross-crystals, reduces the orientation degree, makes the microstructure more uniform, reduces scattering centers, further suppresses light scattering and improves transmittance.

[0031] 2. Flat glass fibers and antireflective modifiers are added to PA66 resin. Compared with traditional round glass fibers, the sheet-like structure of flat glass fibers scatters laser light less. The rectangular cross-section of flat glass fibers makes them more orderly arranged in the PA66 matrix, reducing interfacial discontinuities and thus lowering the light scattering center. Flat glass fibers have a larger specific surface area, which can more uniformly contact and transmit light. Combined with the light transmittance improvement effect of antireflective modifiers, the light transmittance and low scattering effect of the finished material are further improved.

[0032] 3. After plasma etching, the flat glass fiber filaments reduce light scattering caused by impurities. The hydroxyl groups in the etched pits on the surface of the flat glass fiber after etching are easily connected with the silane coupling agent KH-550, which improves light transmittance and reduces light scattering. In addition, the surface of the flat glass fiber filaments contains free amino groups of the silane coupling agent KH-550. These free amino groups are connected with the amino and carboxyl groups in chitosan by hydrogen bonds. The surface of the flat glass fiber filaments is loaded with chitosan, which carries a positive charge. This causes the flat glass fiber to be arranged in an orderly parallel orientation in PA66, which can suppress the multiple scattering effect and thus reduce light scattering. Detailed Implementation

[0033] The present application will be further described in detail below with reference to the embodiments.

[0034] Preparation example of flat glass fiber All of the following ingredients are commercially available.

[0035] Preparation Example 1: Flat glass fibers were prepared using the following method: 0.2 kg of sodium carboxymethyl cellulose solution (0.5% by mass) was uniformly sprayed onto the surface of 1 kg of EPDM-g-MAH particles. After drying and dispersion, carboxyl-modified EPDM-g-MAH was obtained. 1 kg of chitosan acetate solution and 0.15 kg of carboxyl-modified EPDM-g-MAH were mixed and stirred evenly. The concentration of chitosan acetate solution was 2%, and the concentration of acetate was 2%, to obtain a chitosan composite solution. Flat glass fibers with an average length of 3 mm, a flatness ratio of 1:4, and an average etching depth of 80 nm were plasma etched. The etched flat glass fibers were then immersed in silane coupling agent KH-550 at a mass ratio of 1:10. The stirring speed during immersion was 500 r / min, and the immersion time was 30 min. The flat glass fibers were then filtered out and immersed and dispersed in chitosan composite solution at a mass ratio of 1:10. The stirring speed during immersion was 500 r / min, and the stirring time was 20 min. The solution was then heated to 80℃ for 20 min, and finally the fibers were air-dried to obtain the finished flat glass fibers.

[0036] Preparation Example 2: The difference between this preparation example and Preparation Example 1 is that: 0.2 kg of sodium carboxymethyl cellulose solution (0.5% by mass) was uniformly sprayed onto the surface of 1 kg of EPDM-g-MAH particles. After drying and dispersion, carboxyl-modified EPDM-g-MAH was obtained. 1 kg of chitosan acetate solution and 0.1 kg of carboxyl-modified EPDM-g-MAH were mixed and stirred evenly. The concentration of chitosan acetate solution was 2%, and the concentration of acetate was 2%, to obtain a chitosan composite solution. Flat glass fibers with an average length of 3 mm and a flatness ratio of 1:3.5 were plasma etched to achieve an average etching depth of 80 nm. The etched flat glass fibers were then immersed in silane coupling agent KH-550 at a mass ratio of 1:10. The stirring speed during immersion was 500 r / min, and the immersion time was 30 min. The flat glass fibers were then filtered out and immersed in chitosan composite solution at a mass ratio of 1:10 for dispersion. The stirring speed during immersion was 500 r / min, and the stirring time was 20 min. The solution was then heated to 80℃ for 20 min, and finally the fibers were air-dried to obtain the finished flat glass fibers.

[0037] Preparation Example 3: The difference between this preparation example and Preparation Example 1 is that: 0.2 kg of sodium carboxymethyl cellulose solution (0.5% by mass) was uniformly sprayed onto the surface of 1 kg of EPDM-g-MAH particles. After drying and dispersion, carboxyl-modified EPDM-g-MAH was obtained. 1 kg of chitosan acetate solution was mixed with 0.2 kg of carboxyl-modified EPDM-g-MAH and stirred evenly. The concentration of chitosan acetate solution was 2%, and the concentration of acetate was 2%, to obtain a chitosan composite solution. Flat glass fibers were plasma etched with an average length of 3 mm and an average etching depth of 80 nm. The etched flat glass fibers were then immersed in silane coupling agent KH-550 at a mass ratio of 1:10. The stirring speed during immersion was 500 r / min, and the immersion time was 30 min. The flat glass fibers were then filtered out and immersed and dispersed in chitosan composite solution at a mass ratio of 1:10. The stirring speed during immersion was 500 r / min, and the stirring time was 20 min. The solution was then heated to 80℃ and treated for 20 min. Finally, the fibers were air-dried to obtain the finished flat glass fibers.

[0038] Preparation example of modified graphene microsheets All of the following raw materials are commercially available.

[0039] Preparation Example 4: Modified graphene microsheets were prepared using the following method: Triethylene adipate was heated to 70°C and completely melted to obtain a molten triethylene adipate solution. 0.15 kg of the molten triethylene adipate solution was uniformly sprayed onto the surface of 1 kg of graphene nanosheets with an average particle size of 120 nm. During the spraying process, the graphene nanosheets were continuously stirred at 80 r / min. After drying and dispersing, the modified graphene nanosheets were obtained.

[0040] Preparation Example 5: The difference between this preparation example and Preparation Example 4 is that: Triethylene adipate was heated to 70°C and completely melted to obtain a molten triethylene adipate solution. 0.1 kg of the molten triethylene adipate solution was uniformly sprayed onto the surface of 1 kg of graphene nanosheets with an average particle size of 80 nm. During the spraying process, the graphene nanosheets were continuously stirred at 80 r / min. After drying and dispersing, the modified graphene nanosheets were obtained.

[0041] Preparation Example 6: The difference between this preparation example and Preparation Example 4 is that: Triethylene adipate was heated to 70°C and completely melted to obtain a molten triethylene adipate solution. 0.18 kg of the molten triethylene adipate solution was uniformly sprayed onto the surface of 1 kg of graphene nanosheets with an average particle size of 200 nm. During the spraying process, the graphene nanosheets were continuously stirred at 80 r / min. After drying and dispersing, the modified graphene nanosheets were obtained. Example

[0042] The hyperbranched resin in the following raw materials was purchased from Wenzhou Longou New Material Technology Co., Ltd., brand name LD-303; the other raw materials are all commercially available.

[0043] Example 1: A laser-enhanced PA66 material with high transmittance: The mixture consists of 50 kg of PA66 resin, 15 kg of PA6I / 6T resin, 32 kg of flat glass fiber, 1.5 kg of antireflective modifier, 0.3 kg of flow agent, 0.3 kg of lubricant, and 0.2 kg of antioxidant. The flat glass fiber is the same as that prepared in Preparation Example 1. The antireflective modifier is composed of modified graphene microsheets and polyphenylene sulfide microparticles prepared in Preparation Example 4 at a mass ratio of 1:0.8. The average particle size of the polyphenylene sulfide microparticles is 2 μm. The flow agent is hyperbranched resin. The lubricant is composed of erucamide and microcrystalline wax at a mass ratio of 1:1. The antioxidant is composed of antioxidant 9228 and antioxidant 1098 at a mass ratio of 1:0.25. The preparation method is as follows: S1. Weigh PA66 resin, PA6I / 6T resin, flat glass fiber, antireflective modifier, flow agent, lubricant, and antioxidant, mix and stir evenly to obtain a mixture; S2. The mixture is melt-extruded to obtain the finished product.

[0044] Example 2: The difference between this example and Example 1 is that: The mixture consists of 56 kg of PA66 resin, 10 kg of PA6I / 6T resin, 30 kg of flat glass fiber, 1 kg of antireflective modifier, 0.2 kg of flow agent, 0.1 kg of lubricant, and 0.1 kg of antioxidant. The flat glass fiber is the same as that prepared in Preparation Example 2. The antireflective modifier is composed of modified graphene microsheets and polyphenylene sulfide microparticles prepared in Preparation Example 5 at a mass ratio of 1:0.5. The average particle size of the polyphenylene sulfide microparticles is 1 μm. The flow agent is hyperbranched resin. The lubricant is composed of erucamide and microcrystalline wax at a mass ratio of 1:0.5. The antioxidant is composed of antioxidant 9228 and antioxidant 1098 at a mass ratio of 1:0.2. Example 3: The difference between this example and Example 1 is that: The mixture consists of 43 kg of PA66 resin, 20 kg of PA6I / 6T resin, 35 kg of flat glass fiber, 2 kg of antireflective modifier, 0.2 kg of flow agent, 0.5 kg of lubricant, and 0.3 kg of antioxidant. The flat glass fiber is the same as that prepared in Preparation Example 3. The antireflective modifier is composed of modified graphene microsheets and polyphenylene sulfide microparticles prepared in Preparation Example 6 at a mass ratio of 1:1. The average particle size of the polyphenylene sulfide microparticles is 3 μm. The flow agent is hyperbranched resin. The lubricant is composed of erucamide and microcrystalline wax at a mass ratio of 1:0.8. The antioxidant is composed of antioxidant 9228 and antioxidant 1098 at a mass ratio of 1:0.5.

[0045] Example 4: The difference between this example and Example 1 is that: The flat glass fiber is untreated with silane coupling agent KH-550.

[0046] Example 5: The difference between this example and Example 1 is that: The flat glass fiber was not treated with chitosan composite solution during the preparation process.

[0047] Example 6: The difference between this example and Example 1 is that: In the preparation of flat glass fibers, the chitosan composite solution is replaced with an equal mass of chitosan acetate solution.

[0048] Example 7: The difference between this example and Example 1 is that: No polyphenylene sulfide microparticles were added to the permeability modifier.

[0049] Example 8: The difference between this example and Example 1 is that: The modified graphene microsheets are replaced with graphene microsheets of equal mass in the antireflective modifier.

[0050] Comparative Example Comparative Example 1: The difference between this comparative example and Example 1 is that: No flat glass fibers or antireflective modifiers were added to the raw materials.

[0051] Comparative Example 2: This comparative example differs from Example 1 in that: PA6I / 6T resin was not added to the raw materials.

[0052] Performance testing 1. Laser transmittance testing Finished materials were prepared using the methods of Examples 1-8 and Comparative Examples 1-2, respectively. Transmittance data were recorded by using a near-infrared spectrometer at 980 nm on a 2 mm thick color plate.

[0053] 2. Flatness inspection Finished materials were prepared using the methods of Examples 1-5 and Comparative Example 1, respectively. Warpage data were recorded using a laser flatness measuring instrument. High warpage indicates low flatness.

[0054] Table 1 Performance Test Table (Note: " / " in the table indicates that this item was not tested in this embodiment and no data is displayed)

[0055] As can be seen from Examples 1-3 and Table 1, the PA66 material prepared in this application has high laser transmittance and low warpage, indicating that the finished material has both good light transmittance and high flatness.

[0056] Combining Examples 1 and 4-8 with Table 1, it can be seen that the flat glass fiber in Example 4 was not treated with silane coupling agent KH-550. Compared with Example 1, the laser transmittance of the PA66 material prepared in Example 4 was lower than that in Example 1, and the warpage was higher than that in Example 1. This indicates that the hydroxyl groups of the etched pits on the surface of the flat glass fiber are easy to connect with silane coupling agent KH-550, thereby improving light transmittance and reducing light scattering. Furthermore, the silane coupling agent KH-550 on the surface of the flat glass fiber can improve the compatibility and connection effect between the flat glass fiber and PA66, resist stress, thereby controlling the warpage and ensuring the flatness of the finished material.

[0057] In Example 5, the flat glass fiber was not treated with chitosan composite solution during preparation. Compared to Example 1, the laser transmittance of the PA66 material prepared in Example 5 was lower than that in Example 1, while the warpage was higher. This indicates that the surface of the flat glass fiber contains free amino groups from the silane coupling agent KH-550. These free amino groups are hydrogen-bonded with the amino and carboxyl groups in chitosan. The surface of the flat glass fiber is loaded with chitosan, which carries a positive charge. This allows the flat glass fiber to be arranged in an orderly parallel orientation within PA66, which can suppress multiple scattering effects and thus reduce light scattering. Furthermore, EPDM-g-MAH can improve the compatibility and bonding effect between the flat glass fiber and PA66, control and reduce warpage, and ensure flatness.

[0058] In Example 6, during the preparation of flat glass fibers, the chitosan composite solution was replaced with an equal mass of chitosan acetate solution. Compared to Example 1, the laser transmittance of the PA66 material prepared in Example 6 was lower than that in Example 1. This indicates that the carboxyl groups in the carboxyl-modified EPDM-g-MAH can be attracted and linked to the free amino groups on the surface of the flat glass fiber, and can be distributed and filled in the nano-pits etched by plasma etching. With subsequent heating treatment, EPDM-g-MAH is thermally melted and flowed on the surface of the flat glass fiber. The thermally melted and flowed EPDM-g-MAH can fill the pits of the flat glass fiber, improve the flatness of the flat glass fiber, thereby reducing the light scattering of PA66 and ensuring the laser transmittance of the PA66 material.

[0059] In Example 7, no polyphenylene sulfide (PPS) microparticles were added to the antireflection modifier. Compared to Example 1, the laser transmittance of the PA66 material prepared in Example 7 was lower than that in Example 1. This indicates that the refractive index difference between PPS and PA66 lies between the refractive index difference between graphene microsheets and PA66. By controlling the limitation of the refractive index gradient, the intensity of Mie scattering at the interface can be weakened. PPS microparticles can act as heterogeneous nucleating agents, reducing the nucleation barrier of PA66 and promoting the simultaneous generation of more crystal nuclei. This refines the grain size while suppressing light scattering caused by large-sized spherulites, thereby ensuring the laser transmittance of PA66 material.

[0060] In Example 8, the modified graphene microsheets were replaced with graphene microsheets of equal mass in the antireflection modifier. Compared with Example 1, the laser transmittance of the PA66 material prepared in Example 8 was lower than that in Example 1. This indicates that triethylene adipate ester constructs a continuous refractive index gradient transition region between graphene and PA66, buffering the refractive index difference between graphene microsheets and PA66, resulting in a smoother refractive index transition and significantly weakening the Mie scattering intensity. Furthermore, triethylene adipate ester can form hydrogen bonds with the amide groups in the PA66 molecular chain, enhancing the melt blending compatibility of graphene microsheets and PA66, reducing light scattering, and thus ensuring the laser transmittance of the PA66 material.

[0061] Combining Example 1 and Comparative Example 1 with Table 1, it can be seen that Comparative Example 1 did not add flat glass fibers and antireflective modifiers to its raw materials. Compared with Example 1, the laser transmittance of the PA66 material prepared in Comparative Example 1 was lower than that of Example 1, while the warpage was higher. This indicates that the combination of flat glass fibers and antireflective modifiers added to PA66 resin results in weaker laser scattering due to the sheet-like structure of the flat glass fibers compared to traditional circular glass fibers. The rectangular cross-section of the flat glass fibers allows for a more orderly arrangement within the PA66 matrix, reducing interfacial discontinuities and thus lowering the light scattering center. The larger specific surface area of ​​the flat glass fibers allows for more uniform light contact and transmission. Combined with the light transmittance-enhancing effect of the antireflective modifier, this further improves the transmittance and low scattering effect of the finished material. Furthermore, the formed three-dimensional structural network suppresses warpage, thereby ensuring the flatness of the finished product.

[0062] In Comparative Example 2, no PA6I / 6T resin was added to the raw materials. Compared to Example 1, the laser transmittance of Comparative Example 2 was lower than that of Example 1. This indicates that the combination of PA66 resin and PA6I / 6T resin, with the introduction of rigid aromatic rings by the isophthalic acid units (PA6I) in PA6I / 6T resin, can disrupt the regularity of the PA66 molecular chain, reduce crystallinity, suppress light scattering, and improve transmittance. Furthermore, the high molecular weight segments of PA6I / 6T resin act as heterogeneous nucleating agents, refining the grain size. The amorphous structure of PA6I / 6T hinders the formation of cross-crystals, reduces orientation, makes the microstructure more uniform, reduces scattering centers, further suppresses light scattering, and improves transmittance.

[0063] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A laser-enhanced high-transmittance PA66 material, characterized in that, It contains the following raw materials in parts by weight: 43-56 parts PA66 resin, 10-20 parts PA6I / 6T resin, 30-35 parts flat glass fiber, 1-2 parts antireflective modifier, 0.2-0.3 parts flow agent, 0.1-0.5 parts lubricant, and 0.1-0.3 parts antioxidant.

2. The laser-enhanced high-transmittance PA66 material according to claim 1, characterized in that: The flat glass fiber is prepared by plasma etching of flat glass fiber filaments, impregnation with silane coupling agent KH-550, treatment with chitosan composite solution, and then heating treatment.

3. The laser-enhanced high-transmittance PA66 material according to claim 2, characterized in that, The chitosan composite solution was prepared by mixing chitosan acetate solution and carboxyl-modified EPDM-g-MAH in a mass ratio of 1:0.1-0.

2.

4. The laser-enhanced high-transmittance PA66 material according to claim 1, characterized in that, The antireflective modifier is prepared from modified graphene microsheets and modified polyphenylene sulfide microparticles in a mass ratio of 1:0.5-1.

5. The laser-enhanced high-transmittance PA66 material according to claim 4, characterized in that, The modified graphene microsheets are prepared by mixing nano-graphene microsheets and triethylene adipate in a mass ratio of 1:0.1-0.

18.

6. The laser-enhanced high-transmittance PA66 material according to claim 5, characterized in that, The average particle size of the graphene nanosheets is 80-200 nm, and the average particle size of the polyphenylene sulfide microparticles is 1-3 μm.

7. The laser-enhanced high-transmittance PA66 material according to claim 1, characterized in that, The flow agent is a hyperbranched resin.

8. The laser-enhanced high-transmittance PA66 material according to claim 1, characterized in that, The lubricant is composed of erucamide and microcrystalline wax in a mass ratio of 1:0.5-1.

9. The laser-enhanced high-transmittance PA66 material according to claim 1, characterized in that, The antioxidant is composed of antioxidant 9228 and antioxidant 1098 in a mass ratio of 1:0.2-0.

5.

10. A method for preparing a laser-enhanced high-transmittance PA66 material according to any one of claims 1-9, characterized in that, Includes the following steps: S1. Weigh PA66 resin, PA6I / 6T resin, flat glass fiber, antireflective modifier, flow agent, lubricant, and antioxidant, mix and stir evenly to obtain a mixture; S2. The mixture is melt-extruded to obtain the finished product.

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