Hydrolysis-resistant PBT (polybutylene terephthalate) reinforced material capable of being subjected to laser welding and preparation method of hydrolysis-resistant PBT reinforced material

Abstract

The invention discloses a hydrolysis-resistant PBT reinforced material capable of being subjected to laser welding and a preparation method of the hydrolysis-resistant PBT reinforced material, and belongs to the field of engineering plastics. Comprising the following raw materials in parts by mass: 45-70 parts of PBT resin, 0.5-1 part of a nucleating agent, 0.5-1 part of a nucleating auxiliary agent, 0.1-1 part of an antioxidant, 0.1-1 part of a lubricant, 0.2-0.8 part of a hydrolysis-resistant agent, 1-3 parts of a toughening agent and 25-45 parts of glass fibers, the nucleating auxiliary agent is sodium-doped potassium aluminosilicate. The nucleating agent can improve the crystallization rate of PBT, refine the grain size and reduce light scattering, and the hydrolysis-resistant agent can block autocatalytic hydrolysis circulation. And the composite sodium-doped potassium aluminosilicate not only can provide a large number of sites for PBT nucleation, but also can adsorb and capture water molecules in the environment and small molecules in an adsorption material and reduce hydrolysis reaction, so that the reinforced PBT material can be suitable for laser welding, and the long-term stability of the material in a high-temperature and humid environment can be guaranteed.

Description

Technical Field

[0001] This invention relates to the field of engineering plastics, and in particular to a laser-weldable hydrolysis-resistant PBT reinforced material and its preparation method. Background Technology

[0002] Plastic laser welding typically uses infrared lasers as the welding heat source. The upper material needs to have high laser transmittance. When the laser passes through the upper material and reaches the surface of the lower material, the lower material has a high laser absorption rate. This allows the laser to absorb a large amount of heat at the interface, melting the plastic. Then, under clamping force, secondary polymerization occurs. After cooling, a weld seam forms at the interface, and the parts are welded together. Compared to traditional ultrasonic welding, vibration welding, or hot plate welding, plastic laser welding produces precise and strong welds that are airtight, watertight, and have excellent sealing performance. It also produces no residue. As a non-contact welding method, it leaves no damage to the surface of the welded parts, significantly reducing vibration and thermal stress during the welding process, thus extending the product's lifespan.

[0003] Traditional PBT materials face a significant bottleneck in laser welding: their semi-crystalline properties result in low laser transmittance. In particular, PBT materials reinforced with glass fiber have an infrared transmittance of less than 10% in the 800–1100 nm wavelength range, leading to low weld interface strength and failing to meet the requirements of infrared welding. With the increasing demand for lightweight materials, the development of a laser-weldable PBT-reinforced composite material is of great significance.

[0004] Furthermore, due to the poor stability of polyester polymers to moisture, they are prone to hydrolysis. Under high temperature and humidity conditions, the ester bonds in the polymer react with water, causing the long chain structure of the macromolecule to break, resulting in a significant decrease in the mechanical properties of the material. In addition, the carboxyl groups generated by hydrolysis will further catalyze the hydrolysis reaction with acid, leading to a significant reduction in the various properties of polyester materials and a greatly shortened service life.

[0005] Therefore, it is of great significance to provide a glass fiber reinforced PBT material that can be laser welded and is resistant to hydrolysis, in order to address the shortcomings of existing technologies. Summary of the Invention

[0006] This invention provides a laser-weldable hydrolysis-resistant PBT reinforced material and its preparation method, which can solve the problems of existing glass fiber reinforced PBT materials not meeting infrared welding requirements and having poor hydrolysis resistance.

[0007] In a first aspect, the present invention provides a laser-weldable hydrolysis-resistant PBT reinforced material, comprising the following raw materials in parts by weight: 45-70 parts of PBT resin; Nucleating agent 0.5 to 1 part; Nucleating agent 0.5-1 part; Antioxidant 0.1 to 1 part; Lubricant 0.1 to 1 part; Hydrolysis resistant agent: 0.2–0.8 parts; 1-3 parts toughening agent; 25-45 parts glass fiber; The nucleating agent is sodium-doped potassium aluminum silicate.

[0008] Preferably, the nucleating agent includes one or more combinations of sodium lignite, sodium benzoate, inorganic sodium salts, and sarin resin.

[0009] Preferably, the intrinsic viscosity of the PBT resin is 0.75 to 0.85 dL / g.

[0010] Preferably, the antioxidant includes one or a combination of two of antioxidant 1010 and antioxidant 245.

[0011] Preferably, the lubricant includes one or more combinations of lignite wax, polyethylene wax, ethylene bis-stearamide, and pentaerythritol stearate.

[0012] Preferably, the hydrolysis resistant agent includes one or a combination of two of carbodiimide and polycarbodiimide.

[0013] Preferably, the toughening agent includes one or a combination of two of the following: ethylene-acrylate-glycidyl methacrylate terpolymer and ethylene-octene methacrylate grafted copolymer.

[0014] Preferably, the glass fiber is chopped glass fiber; the diameter of the single filament of the chopped glass fiber is 7 to 14 μm.

[0015] By adopting the above technical solution, the present invention adds a nucleating agent, which can significantly improve the crystallization rate of PBT and refine the grain size. By providing heterogeneous nucleation sites, it promotes the formation of more and smaller grains in PBT resin during the cooling process, thereby reducing light scattering and improving laser transmittance. This avoids the formation of larger spherulites due to the semi-crystalline nature of PBT resin, which would cause the infrared laser to be scattered and thus reduce transmittance. Furthermore, the fine grain structure is also conducive to the formation of a more uniform molten layer at the welding interface, thereby enhancing the interface welding strength.

[0016] Hydrolysis-resistant agents can react with the carboxyl groups generated after hydrolysis by introducing active groups to form stable compounds, thereby blocking the autocatalytic hydrolysis cycle and consuming a large number of acidic ends that initiate hydrolysis, thus acting as a capping agent and significantly delaying the aging of the material in humid and hot environments. The combined use of nucleating agents and hydrolysis-resistant agents optimizes the light transmittance of the material, making reinforced PBT materials suitable for laser welding, and also ensures the long-term stability of the material in high-temperature and humid environments.

[0017] Furthermore, this invention incorporates a nucleation aid, specifically sodium-doped potassium aluminum silicate. Sodium-doped potassium aluminum silicate is itself a highly efficient heterogeneous nucleation agent, capable of providing nucleation sites through its mesoporous surface, inducing PBT to arrange itself in an orderly manner within the channels and on its surface, forming a large number of fine, uniform crystal nuclei. Moreover, the sodium-doped potassium aluminum silicate of this invention introduces sodium ions. The addition of sodium ions not only matches the polarity of the PBT chain segments but also promotes interfacial epigenesis in the early stages of crystallization. The fine-grained structure formed synergistically with the nucleation agent significantly reduces laser scattering in the target wavelength band, further improving the laser transmittance of PBT.

[0018] Meanwhile, the ordered mesoporous structure of sodium-doped potassium aluminum silicate can physically adsorb and capture water molecules from the environment, thereby reducing the diffusion of water molecules in the PBT matrix material and delaying the contact between water molecules and ester groups on the PBT molecular chain, thus inhibiting the autocatalytic process of hydrolysis. Furthermore, the introduction of sodium ions can further enhance the ion exchange capacity of the framework, forming a relatively stable hydration layer with water molecules, further reducing the activity of free water.

[0019] On the other hand, the mesoporous structure can also adsorb small molecules in the material, thereby reducing the volatilization of small molecules. Simultaneously, the improved crystallinity results in more regular and ordered molecular chains in the PBT crystalline regions, reducing the formation of by-reaction products, increasing the material's density, and making it more difficult for small molecules to migrate from the material's interior to the surface, further delaying their volatilization. The reduction in the generation and volatilization of small molecules also significantly improves the chemical stability of PBT-reinforced materials. Through this dual protection, the material's service life in humid and hot environments is significantly extended.

[0020] The PBT reinforcement material of the present invention still uses chopped glass fiber as the reinforcement material, which can form a three-dimensional support network in the matrix, thereby significantly improving mechanical strength and rigidity, and obtaining a reinforcement material with better performance.

[0021] Preferably, the raw material for sodium-doped potassium aluminum silicate includes potassium aluminum silicate and composite sodium potassium salt in a mass ratio of 1:(0.2-0.4); The compound sodium-potassium salt comprises potassium and sodium salts in a mass ratio of 100:(0.4-0.7).

[0022] More preferably, potassium salts include potassium nitrate; sodium salts include sodium nitrate.

[0023] Preferably, sodium-doped potassium aluminum silicate is prepared by the following method: Potassium aluminum silicate is preheated at 400-500℃ for 1-2 hours, then composite sodium potassium salt is added, and the temperature is maintained for another 3-5 hours. After cooling, it is washed and dried to obtain the final product.

[0024] By adopting the above technical solution, potassium aluminum silicate can remove some adsorbed water after preheating, which relaxes the crystal structure and provides more channels for the subsequent diffusion of sodium ions. Then, composite sodium potassium salt is added. Sodium ions have a smaller ionic radius and can more easily migrate into the framework vacancies of potassium aluminum silicate or replace some potassium ion sites to achieve ion exchange, thereby obtaining sodium-doped potassium aluminum silicate.

[0025] Sodium-doped potassium aluminum silicate promotes the formation of finer and more regular crystalline regions in PBT molecules, thereby reducing infrared laser scattering, increasing laser transmittance, and meeting the requirements of infrared laser welding. Furthermore, it optimizes the interfacial bonding between potassium aluminum silicate and the PBT matrix, inhibiting the aggregation and diffusion of water molecules at the interface, and adsorbing small molecule byproducts, thus maintaining the mechanical properties of PBT-reinforced materials after damp heat aging.

[0026] Preferably, the sodium-doped potassium aluminum silicate has undergone a modification treatment; the modification treatment specifically includes the following steps: Sodium-doped potassium aluminum silicate is dispersed in toluene, vinyl silane coupling agent is added, the temperature is raised to 100-120°C under nitrogen atmosphere, the reaction is stirred for 4-5 hours, the temperature is lowered to 75-85°C, glycidyl methacrylate and initiator are added dropwise, the reaction is stirred for another 3-4 hours, and finally the product is obtained by centrifugation, washing and drying.

[0027] Preferably, the mass ratio of sodium-doped potassium aluminum silicate, vinyl silane coupling agent and glycidyl methacrylate is 1:(0.25-0.35):(0.3-0.5).

[0028] More preferably, the vinyl silane coupling agent includes one or more combinations of vinyltrimethoxysilane, vinyltriethoxysilane, and γ-methacryloyloxypropyltrimethoxysilane.

[0029] More preferably, the initiator includes one or more of benzoyl peroxide, azobisisobutyronitrile, dicumyl peroxide and tert-butyl peroxide; the amount of initiator added is 0.5 to 2 wt% of the mass of glycidyl methacrylate.

[0030] By adopting the above technical solution, the nucleating agent, namely sodium-doped potassium aluminum silicate, is an inorganic filler. Its dispersion in the organic matrix, namely PBT matrix, is not good. Therefore, during the melt processing, these inorganic particles will inevitably spontaneously agglomerate due to intermolecular forces such as van der Waals forces, forming micron-sized or even larger aggregates. These aggregates will become stress concentration points in the matrix, which will damage the mechanical properties of the material and reduce the interfacial bonding force between sodium-doped potassium aluminum silicate and the matrix.

[0031] To address these issues, the nucleating agent was modified. The modified sodium-doped potassium aluminum silicate surface was bonded with glycidyl methacrylate segments. Specifically, vinyl groups were first bonded to the sodium-doped potassium aluminum silicate surface using a vinyl silane coupling agent. Then, the initiator was heated and decomposed to generate free radicals. These free radicals attacked the vinyl double bonds grafted onto the filler surface and initiated the growth of glycidyl methacrylate molecular chains, which were then chemically bonded to the sodium-doped potassium aluminum silicate surface.

[0032] After modification, the long chains on the surface can form a steric hindrance layer, which effectively blocks direct contact between inorganic particles, prevents agglomeration, and improves compatibility with the PBT matrix, so that it can be better wetted and dispersed by the PBT melt during melt blending, achieving uniform distribution.

[0033] Furthermore, after modification, the nucleating agent can form a strong interfacial bond with the PBT matrix, thereby eliminating microscopic defects and gaps at the interface, making it difficult for water to find a low-resistance penetration channel, and further blocking the water penetration path; and even if the PBT molecular chains inside the matrix undergo a certain degree of hydrolysis, the strong interface can continue to effectively transfer stress, so that the material can still maintain a high mechanical property retention rate after aging.

[0034] Secondly, the present invention provides a method for preparing a laser-weldable, hydrolysis-resistant PBT reinforced material, comprising the following process steps: S1. Dry the PBT resin at 90-100℃ for 4-5 hours; S2. Weigh the raw materials according to the corresponding mass fractions, mix them evenly to obtain the premix; S3. The premix is ​​obtained by melt plasticizing and extrusion granulation, wherein the glass fiber is introduced by side feeding.

[0035] The beneficial effects of this invention are: 1. The laser-weldable hydrolysis-resistant PBT reinforced material of the present invention contains a nucleating agent and a hydrolysis-resistant agent. The nucleating agent can improve the crystallization rate of PBT and refine the grain size, reduce light scattering, and thus improve laser transmittance. The hydrolysis-resistant agent can react with the carboxyl groups generated after hydrolysis by introducing active groups to form a stable compound, thereby blocking the autocatalytic hydrolysis cycle. The two work synergistically to optimize the transmittance of the material, making the reinforced PBT material suitable for laser welding, and can also ensure the long-term stability of the material in high temperature and humid environment.

[0036] 2. The laser-weldable hydrolysis-resistant PBT reinforced material of the present invention contains a nucleating agent. Specifically, the nucleating agent is sodium-doped potassium aluminum silicate. On the one hand, it can promote the formation of a large number of fine and uniform crystal nuclei in PBT and improve the laser transmittance of PBT. On the other hand, it can reduce hydrolysis reaction and improve the chemical stability and hydrolysis resistance of the material by physically adsorbing and capturing water molecules in the environment and adsorbing small molecules in the material.

[0037] 3. The sodium-doped potassium aluminum silicate of the present invention has also undergone modification treatment. After modification treatment, it can be better wetted and dispersed by PBT melt during melt blending, so as to achieve uniform distribution. It can also form a strong interfacial bond with PBT matrix, so that the material can still maintain a high mechanical property retention rate after aging. Detailed Implementation

[0038] The specific embodiments of the present invention will be described in detail below, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0039] Preparation Example

[0040] Preparation Example 1: A sodium-doped potassium aluminum silicate was prepared according to the following method: 10g of potassium aluminum silicate (average particle size of 350 mesh) was preheated at 450℃ for 1h, and then 3g of composite sodium potassium salt was added, wherein the composite sodium potassium salt consisted of potassium nitrate and sodium nitrate in a mass ratio of 100:0.6. The mixture was kept at this temperature for another 4h, and after cooling, it was washed and dried to obtain the final product.

[0041] Preparation Example 2, a sodium-doped potassium aluminum silicate, differs from Preparation Example 1 only in that the composite sodium-potassium salt includes potassium nitrate and sodium nitrate in a mass ratio of 100:0.2.

[0042] Preparation Example 3 is a sodium-doped potassium aluminum silicate, which differs from Preparation Example 1 only in that the composite sodium-potassium salt includes potassium nitrate and sodium nitrate in a mass ratio of 100:0.9.

[0043] Preparation Example 4: A sodium-doped potassium aluminum silicate, differing from Preparation Example 1 only in that the sodium-doped potassium aluminum silicate has undergone modification treatment, specifically including the following steps: 10g of sodium-doped potassium aluminum silicate prepared in Example 1 was dispersed in 500mL of toluene, 3g of vinyltrimethoxysilane was added, the temperature was raised to 110°C under a nitrogen atmosphere, and the reaction was stirred for 4h. Then the temperature was lowered to 80°C, 4g of glycidyl methacrylate and 0.04g of azobisisobutyronitrile were added dropwise, and the reaction was stirred for another 4h. Finally, the product was obtained by centrifugation, washing and drying.

[0044] Example

[0045] Example 1: A laser-weldable, hydrolysis-resistant PBT reinforced material was prepared according to the following method: S1. Dry the PBT resin at 100℃ for 4 hours; S2. Weigh 66.4 parts of dried PBT resin, 0.6 parts of nucleating agent sodium lignite, 0.6 parts of nucleating aid sodium doped potassium aluminum silicate prepared in Preparation Example 1, 0.2 parts of antioxidant 1010, 0.2 parts of lubricant pentaerythritol stearate, 0.6 parts of hydrolysis resistant agent polycarbodiimide, and 2 parts of toughening agent ethylene-acrylate-glycidyl methacrylate ternary polymer, mix them evenly to obtain a premix; S3. The premix is ​​obtained by melt plasticizing and extrusion granulation, wherein the extrusion temperature is set to 150℃, 240℃, 240℃, 240℃, 230℃, 225℃, 220℃, 220℃, 235℃, 235℃, 250℃, and 30 parts of chopped glass fiber are introduced through side feeding.

[0046] Example 2: A laser-weldable, hydrolysis-resistant PBT reinforced material was prepared according to the following method: S1. Dry the PBT resin at 100℃ for 4 hours; S2. Weigh 66.4 parts of dried PBT resin, 0.6 parts of nucleating agent sodium benzoate, 0.6 parts of nucleating aid sodium doped potassium aluminum silicate prepared in Preparation Example 1, 0.2 parts of antioxidant 1010, 0.2 parts of lubricant pentaerythritol stearate, 0.6 parts of hydrolysis resistant agent polycarbodiimide and 2 parts of toughening agent ethylene-acrylate-glycidyl methacrylate ternary polymer, mix them evenly to obtain a premix; S3. The premix is ​​obtained by melt plasticizing and extrusion granulation, wherein the extrusion temperature is set to 150℃, 240℃, 240℃, 240℃, 230℃, 225℃, 220℃, 220℃, 235℃, 235℃, 250℃, and 30 parts of chopped glass fiber are introduced through side feeding.

[0047] Example 3: A laser-weldable, hydrolysis-resistant PBT reinforced material was prepared according to the following method: S1. Dry the PBT resin at 100℃ for 4 hours; S2. Weigh 56.6 parts of dried PBT resin, 0.4 parts of nucleating agent sodium benzoate, 0.6 parts of nucleating aid sodium doped potassium aluminum silicate prepared in Preparation Example 1, 0.2 parts of antioxidant 1010, 0.2 parts of lubricant pentaerythritol stearate, 0.6 parts of hydrolysis resistant agent polycarbodiimide and 2 parts of toughening agent ethylene-acrylate-glycidyl methacrylate ternary polymer, mix them evenly to obtain a premix; S3. The premix is ​​obtained by melt plasticizing and extrusion granulation, wherein the extrusion temperature is set to 150℃, 240℃, 240℃, 240℃, 230℃, 225℃, 220℃, 220℃, 235℃, 235℃, 250℃, and 40 parts of chopped glass fiber are introduced through side feeding.

[0048] Example 4: A laser-weldable hydrolysis-resistant PBT reinforced material, which differs from Example 1 only in that an equal amount of sodium-doped potassium aluminum silicate prepared in Example 2 is used instead of sodium-doped potassium aluminum silicate prepared in Example 1.

[0049] Example 5: A laser-weldable hydrolysis-resistant PBT reinforced material, which differs from Example 1 only in that an equal amount of sodium-doped potassium aluminum silicate prepared in Example 3 is used instead of sodium-doped potassium aluminum silicate prepared in Example 1.

[0050] Example 6: A laser-weldable hydrolysis-resistant PBT reinforced material, which differs from Example 1 only in that an equal amount of sodium-doped potassium aluminum silicate prepared in Example 4 is used instead of sodium-doped potassium aluminum silicate prepared in Example 1.

[0051] Comparative Example

[0052] Comparative Example 1 is a laser-weldable hydrolysis-resistant PBT reinforced material, which differs from Example 1 only in that it does not contain the nucleating agent sodium lignite.

[0053] Comparative Example 2 is a laser-weldable hydrolysis-resistant PBT reinforced material, which differs from Example 1 only in that it does not contain the hydrolysis-resistant agent polycarbodiimide.

[0054] Comparative Example 3 is a laser-weldable hydrolysis-resistant PBT reinforced material, which differs from Example 1 only in that the sodium-doped potassium aluminum silicate prepared in Example 1 is not added.

[0055] Performance testing

[0056] 1. Laser transmittance test: According to the relevant records in GB / T 2410-2008 "Determination of transmittance and haze of transparent plastics", the PBT reinforced materials obtained in the examples and comparative examples were tested. The test wavelength was 980nm and the sample thickness was 1mm. 2. Hydrolysis resistance test: The PBT reinforced materials obtained in the examples and comparative examples were used to prepare standard type 1A tensile strength test specimens according to the relevant records in ISO 527-2-2012 "Determination of tensile properties of plastics - Part 2: Test conditions for molded and extruded plastics". According to the relevant records in GB / T 1040-2018 "Determination of Tensile Properties of Plastics", the tensile strength of the samples was tested. Then, each sample was placed in a constant temperature and humidity chamber for 1000 hours of aging. The test temperature was 85℃ and the test humidity was 85%. After the experiment, tensile strength tests were continued, and the tensile strength retention rate before and after the test was calculated, as shown below: .

[0057] The results of the above experiments are shown in Table 1: Table 1 Performance test results

[0058] According to Table 1, and in conjunction with Examples 1, 4, and 5, it can be seen that the laser transmittance and tensile strength retention of Examples 4 and 5 are lower than those of Example 1. This is because Example 4 reduces the sodium ion content in sodium-doped potassium aluminum silicate, thus reducing the adjustment effect of the nucleating agent on the PBT substrate and its effect on inhibiting water molecule diffusion, resulting in a decrease in the material's laser transmittance and hydrolysis resistance. In Example 5, the sodium ion content in sodium-doped potassium aluminum silicate is increased, thus replacing most of the potassium ions in the original potassium aluminum silicate, which leads to partial damage to the crystal structure, a decrease in the adsorption capacity for water molecules, and a decrease in the ability to promote nucleation, correspondingly resulting in a decrease in the material's laser transmittance and hydrolysis resistance.

[0059] As can be seen from the combination of Examples 1 and 6, the transmittance and tensile strength retention of Example 6 are improved compared with Example 1. The reason is that the sodium-doped potassium aluminum silicate added in Example 6 has been modified and has glycidyl methacrylate segments grafted on its surface. On the one hand, it can greatly improve the dispersibility and compatibility of sodium-doped potassium aluminum silicate in PBT matrix material, so that it can be uniformly dispersed in PBT melt. On the other hand, it can strengthen the bond with PBT matrix resin, thereby further blocking the water penetration path and improving the hydrolysis resistance of the material.

[0060] Based on Example 1 and Comparative Examples 1 to 3, it can be seen that the transmittance and tensile strength retention of Comparative Examples 1 to 3 are significantly lower than those of Example 1. This is because Comparative Example 1 did not add a nucleating agent, thus failing to promote the formation of more and smaller PBT resin grains during cooling. The nucleating agent alone only provides limited improvement in reducing light scattering, leading to hindered PBT nucleation and a significant decrease in laser transmittance. Comparative Example 2 did not add a hydrolysis-resistant agent, lacking the end-capping effect on the PBT resin molecular weight. The autocatalytic hydrolysis cycle of the PBT resin could not be blocked in time, resulting in accelerated aging of the material under humid and hot conditions and a significant decline in material performance. Comparative Example 3 did not add a nucleating agent, thus reducing its regulatory effect on the nucleation and hydrolysis resistance of the PBT resin, consequently leading to a decrease in laser transmittance and strength retention.

[0061] The above-disclosed embodiments are merely a few specific examples of the present invention. However, the embodiments of the present invention are not limited thereto, and any variations that can be conceived by those skilled in the art should fall within the protection scope of the present invention.

Claims

1. A laser-weldable, hydrolysis-resistant PBT reinforced material, characterized in that, The raw materials include the following parts by weight: 45-70 parts of PBT resin; Nucleating agent 0.5 to 1 part; Nucleating agent 0.5-1 part; Antioxidant 0.1 to 1 part; Lubricant 0.1 to 1 part; Hydrolysis resistant agent: 0.2–0.8 parts; 1-3 parts toughening agent; 25-45 parts glass fiber; The nucleating agent is sodium-doped potassium aluminum silicate.

2. The laser-weldable hydrolysis-resistant PBT reinforced material according to claim 1, characterized in that, The nucleating agent includes one or more of sodium lignite, sodium benzoate, inorganic sodium salts, and sarin resin.

3. The laser-weldable hydrolysis-resistant PBT reinforced material according to claim 1, characterized in that, The raw materials for the sodium-doped potassium aluminum silicate include potassium aluminum silicate and composite sodium potassium salt in a mass ratio of 1:(0.2-0.4); The composite sodium-potassium salt comprises potassium salt and sodium salt in a mass ratio of 100:(0.4-0.7).

4. The laser-weldable hydrolysis-resistant PBT reinforced material according to claim 3, characterized in that, The sodium-doped potassium aluminum silicate was prepared by the following method: Potassium aluminum silicate is preheated at 400-500℃ for 1-2 hours, then composite sodium potassium salt is added, and the temperature is maintained for another 3-5 hours. After cooling, it is washed and dried to obtain the final product.

5. The laser-weldable hydrolysis-resistant PBT reinforced material according to claim 1, characterized in that, The sodium-doped potassium aluminum silicate is further modified; the modification process specifically includes the following steps: Sodium-doped potassium aluminum silicate is dispersed in toluene, vinyl silane coupling agent is added, the temperature is raised to 100-120°C under nitrogen atmosphere, the reaction is stirred for 4-5 hours, the temperature is lowered to 75-85°C, glycidyl methacrylate and initiator are added dropwise, the reaction is stirred for another 3-4 hours, and finally the product is obtained by centrifugation, washing and drying.

6. The laser-weldable hydrolysis-resistant PBT reinforced material according to claim 5, characterized in that, The mass ratio of sodium-doped potassium aluminum silicate, vinyl silane coupling agent, and glycidyl methacrylate is 1:(0.25-0.35):(0.3-0.5).

7. The laser-weldable hydrolysis-resistant PBT reinforced material according to claim 1, characterized in that, The hydrolysis-resistant agent includes one or a combination of two of carbodiimide and polycarbodiimide.

8. The laser-weldable hydrolysis-resistant PBT reinforced material according to claim 1, characterized in that, The toughening agent includes one or a combination of two of the following: ethylene-acrylate-glycidyl methacrylate terpolymer and glycidyl methacrylate-grafted ethylene-octene copolymer.

9. The laser-weldable hydrolysis-resistant PBT reinforced material according to claim 1, characterized in that, The glass fiber is chopped glass fiber; the diameter of the single filament of the chopped glass fiber is 7-14 μm.

10. A method for preparing a laser-weldable hydrolysis-resistant PBT reinforced material, used to prepare the laser-weldable hydrolysis-resistant PBT reinforced material according to any one of claims 1 to 9, characterized in that, The process includes the following steps: S1. Dry the PBT resin at 90-100℃ for 4-5 hours; S2. Weigh the raw materials according to the corresponding mass fractions, mix them evenly to obtain the premix; S3. The premix is ​​obtained by melt plasticizing and extrusion granulation, wherein the glass fiber is introduced by side feeding.

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