A PBT / PET / EP alloy with high laser transmittance and its preparation method

Abstract

The present invention provides a high laser transmittance PBT / PET / EP alloy and a preparation method thereof. The alloy comprises the following raw material components in percentage by weight: 30%-40% of polybutylene terephthalate; 10%-30% of polyethylene terephthalate; 5%-10% of epoxy resin; 0.2%-0.5% of lubricant; 0.2%-0.5% of antioxidant; 20%-40% of glass fiber; 0.5%-1.5% of black dye; the glass fiber is a modified chopped glass fiber obtained by radio frequency magnetron sputtering treatment using alumina as a target.

Description

Technical Field

[0001] The present invention belongs to the technical field of engineering plastic alloy materials, and relates to a PBT / PET / EP alloy with high laser transmittance and a preparation method thereof. Background Art

[0002] With the rapid development of the automotive manufacturing industry, lightweight design, as an important development direction in the automotive manufacturing industry, more and more plastic products are replacing metal components in automotive manufacturing. Laser welding is a method of irradiating a laser beam on a laminated resin molded body, allowing it to pass through the irradiation surface and be absorbed on the other side, and then melting and fusing. Compared with other plastic welding methods, plastic laser welding has the advantages of beautiful welds, small welding deformation, and high strength. In addition, plastic laser welding can also achieve connections from two-dimensional to three-dimensional spaces, breaking the constraints of structure and shape, and has the advantage of high automation, meeting the precision welding requirements of high-end fields such as automotive manufacturing.

[0003] Polybutylene terephthalate (PBT) is a crystalline polymer with relatively low light transmittance itself, and the light transmittance of glass fiber-reinforced PBT is even lower, mainly affected by crystallinity and grain size. At present, domestic and foreign scientific and technological workers have achieved remarkable results in the modification research of glass fiber-reinforced PBT materials with high laser transmittance. For example, Kingfa Science & Technology studied the effects of glass fiber content, glass fiber diameter, and inorganic reactive nucleating agent sodium carbonate on the light transmittance of glass fiber-reinforced PBT; BASF successfully modified the morphology of PBT, increasing the laser transmittance from 30% to nearly 60%.

[0004] However, there are still certain limitations in the existing technology, and there is still room for improvement in further improving the light transmittance of glass fiber-reinforced PBT and improving its performance in complex environments. To solve the above problems, the present invention studied the laser transmission performance of PBT / PET / EP alloy materials in order to meet the requirements for applications such as manufacturing the housing of an electromechanical actuator for vortex control. Summary of the Invention

[0005] Aiming at the problems existing in the prior art, the present invention selects specific PBT, PET, and EP, and subjects glass fiber to radio frequency magnetron sputtering treatment with alumina as the target material to obtain modified short-cut glass fiber. The interaction between the components improves the light transmittance of the alloy material.

[0006] To achieve this purpose, the present invention adopts the following technical solutions:

[0007] In the first aspect, a PBT / PET / EP alloy with high laser transmittance, the alloy comprises the following raw material components in weight percentage:

[0008] Polybutylene terephthalate 30% - 40%;

[0009] Ethylene terephthalate 10% - 30%;

[0010] Epoxy resin 5% - 10%;

[0011] Lubricant 0.2% - 0.5%;

[0012] Antioxidant 0.2% - 0.5%;

[0013] Glass fiber 20% - 40%;

[0014] Black dye 0.5% - 1.5%;

[0015] The glass fiber is modified short - cut glass fiber processed by radio - frequency magnetron sputtering with alumina as the target. The processing process of the modified short - cut glass fiber is as follows: The short - cut glass fiber is placed in a sodium hydroxide solution for cleaning, then rinsed with clean water and put into a pretreatment agent, stirred, and dried to obtain pretreated glass fiber; Using the pretreated glass fiber as the substrate and alumina as the target, radio - frequency magnetron sputtering treatment is carried out to obtain modified short - cut glass fiber; The pretreatment agent is an aqueous solution of cyclohexylaminopropyltrimethoxysilane with a mass fraction of 3% - 5%.

[0016] As a preferred embodiment of the present invention, the polybutylene terephthalate, i.e., PBT, has an intrinsic viscosity of 1.0 ± 0.015 dl / g.

[0017] As a preferred embodiment of the present invention, the ethylene terephthalate, i.e., PET, has an intrinsic viscosity of 0.68 ± 0.01 dl / g.

[0018] As a preferred embodiment of the present invention, the epoxy resin, i.e., EP, is bisphenol A - type epoxy resin with an equivalent weight of 730 - 840 g / eq.

[0019] As a preferred embodiment of the present invention, the alumina is α - phase alumina with a particle size of 40 - 80 nm.

[0020] As a preferred embodiment of the present invention, the lubricant is a mixture of a copolymer and bead - shaped or flake - shaped wax.

[0021] As a preferred embodiment of the present invention, the antioxidant is selected from one or a combination of antioxidant 1076, antioxidant 1010, antioxidant CA, antioxidant 2246, antioxidant 168, antioxidant 1098, and antioxidant 626.

[0022] As a preferred embodiment of the present invention, the black dye is a chemical dye with the chemical name of 2 - sodium pyridyl - 1,3 - phenyl dihydrazine trisulfonate hydrogen salt.

[0023] Second aspect, the present invention provides a method for preparing the aforementioned PBT / PET / EP alloy, and the method includes the following steps:

[0024] Weigh the formula amounts of PBT, PET, EP, lubricant, antioxidant, glass fiber, and black dye, put them into a high-speed mixer, mix and process, discharge, and then extrude and pelletize with a twin-screw extruder, wherein the glass fiber is fed into the twin-screw extruder from the side feeding port, and the PBT / PET / EP alloy is obtained through extrusion and pelletization.

[0025] As a preferred embodiment of the present invention, the processing temperature of the twin-screw extruder is 250-270 °C, the screw speed is 240-360 r / min; the length of the material strip passing through water is 5-7 m, and the water temperature is controlled at -5 °C to 0 °C.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] By adopting a specific combination of PBT, PET, and EP, and interacting with glass fiber, lubricant, etc. in the system, the present invention achieves a transmittance of 50% under the conditions of a 2-mm thickness and a 980-nm laser. At the same time, this alloy also has good mechanical properties and heat resistance, and can be used to manufacture, for example, the housing of an electromechanical actuator for vortex control. Specific Embodiments

[0028] To better illustrate the present invention and facilitate understanding of its technical solutions, the present invention is further described in detail below. However, the following embodiments are merely simple examples of the present invention and do not represent or limit the scope of the rights protection of the present invention. The scope of protection of the present invention is subject to the claims.

[0029] The specific embodiments of the present invention provide a PBT / PET / EP alloy with high laser transmittance, and the alloy includes the following raw material components in weight percentage:

[0030] Polybutylene terephthalate 30%-40%;

[0031] Polyethylene terephthalate 10%-30%;

[0032] Epoxy resin 5%-10%;

[0033] Lubricant 0.2%-0.5%;

[0034] Antioxidant 0.2%-0.5%;

[0035] Glass fiber 20%-40%;

[0036] Black dye 0.5%-1.5%.

[0037] As a more preferred embodiment of the present invention, the polybutylene terephthalate, i.e., PBT, has an intrinsic viscosity of 1.0 ± 0.015 dl / g, and the intrinsic viscosity is measured by GB / T14190-2017.

[0038] As a more preferred embodiment of the present invention, the polyethylene terephthalate, i.e., PET, has an intrinsic viscosity of 0.68 ± 0.01 dl / g, and the intrinsic viscosity is measured by the method of GB / T 14190-2017.

[0039] As a more preferred embodiment of the present invention, the epoxy resin, i.e., EP, is bisphenol A epoxy resin with an equivalent weight of 730 - 840 g / eq, and the equivalent weight is measured by the method of GB / T 4612-2008.

[0040] As a preferred embodiment of the present invention, the weight percentage content of PBT can be 30%, 32%, 34%, 36%, 38% or 40%, etc., but is not limited to the listed values, and other unlisted values within this numerical range are equally applicable; the weight percentage content of PET can be 10%, 15%, 20%, 25% or 30%, etc., but is not limited to the listed values, and other unlisted values within this numerical range are equally applicable; the weight percentage content of EP can be 5%, 6%, 7%, 8%, 9% or 10%, etc., but is not limited to the listed values, and other unlisted values within this numerical range are equally applicable; the weight percentage content of the lubricant can be 0.2%, 0.3%, 0.4% or 0.5%, etc., but is not limited to the listed values, and other unlisted values within this numerical range are equally applicable; the weight percentage content of the antioxidant can be 0.2%, 0.3%, 0.4% or 0.5%, etc., but is not limited to the listed values, and other unlisted values within this numerical range are equally applicable; the weight percentage content of the glass fiber can be 20%, 25%, 30%, 35% or 40%, etc., but is not limited to the listed values, and other unlisted values within this numerical range are equally applicable; the weight percentage content of the black dye can be 0.5%, 0.7%, 0.9%, 1.1% or 1.5%, etc., but is not limited to the listed values, and other unlisted values within this numerical range are equally applicable.

[0041] As a preferred embodiment of the present invention, the glass fiber is a modified chopped glass fiber obtained by radio frequency magnetron sputtering treatment using alumina as a target.

[0042] As a preferred embodiment of the present invention, the alumina is α-phase alumina with a particle size of 40 - 80 nm.

[0043] The treatment process of the modified chopped glass fiber is as follows: The chopped glass fiber is placed in a sodium hydroxide solution for cleaning, and then rinsed with clean water and put into a pretreatment agent, stirred, and dried to obtain pretreated glass fiber; Using the pretreated glass fiber as the substrate and alumina as the target, radio frequency magnetron sputtering treatment is carried out to obtain the modified chopped glass fiber.

[0044] As a preferred embodiment of the present invention, the treatment process of the modified chopped glass fiber is as follows: The chopped glass fiber is placed in a sodium hydroxide solution with a mass fraction of 3% to 5% for cleaning for 20 - 30 minutes, and then rinsed with clean water and put into a pretreatment agent with a mass fraction of 3% - 5%, stirred, and dried to obtain pretreated glass fiber; Using the pretreated glass fiber as the substrate and alumina as the target, radio frequency magnetron sputtering treatment is carried out to obtain the modified chopped glass fiber. When using alumina as the target in radio frequency magnetron sputtering, during the sputtering treatment, the sputtering pressure is controlled at 1.3 - 1.5 Pa, the sputtering power is 250 - 280 W, the sputtering time is 1.7 - 2 h, the vacuum degree is 4.5×10⁻³ Pa, and the argon gas flow rate is 30 - 40 ml / min. The treated sample is annealed at 750 - 800 °C.

[0045] As a preferred embodiment of the present invention, the pretreatment agent is an aqueous solution of cyclohexylaminopropyltrimethoxysilane with a mass fraction of 3% - 5%.

[0046] As a preferred embodiment of the present invention, the lubricant is a mixture of a copolymer and bead-shaped or flaky wax.

[0047] As a preferred embodiment of the present invention, the antioxidant is selected from one or a combination of antioxidant 1076, antioxidant 1010, antioxidant CA, antioxidant 2246, antioxidant 168, antioxidant 1098, and antioxidant 626; As a preferred embodiment of the present invention, the antioxidant includes antioxidant 168 and antioxidant 1098; As a preferred embodiment of the present invention, the mass ratio of antioxidant 168 to antioxidant 1098 is 1:(0.9 - 1.1); As a preferred embodiment of the present invention, the mass ratio of antioxidant 168 to antioxidant 1098 is 1:1.

[0048] As a preferred embodiment of the present invention, the black dye is a chemical dye with the chemical name of 2 - sodium pyridyl - 1,3 - benzenedihydrazine trisulfonate hydrogen salt.

[0049] The specific embodiment part of the present invention also provides a preparation method of the aforementioned PBT / PET / EP alloy, and the method includes the following steps:

[0050] Weigh the formula amounts of PBT, PET, EP, lubricant, antioxidant, glass fiber and black dye, put them into a high-speed mixer, mix and process, discharge the material, and then extrude and pelletize with a twin-screw extruder. The glass fiber is fed into the twin-screw extruder from the side feeding port, and a PBT / PET / EP alloy is obtained through extrusion and pelletization.

[0051] As a preferred embodiment of the present invention, the mixing and processing time is 3 min - 5 min, such as 3 min, 4 min or 5 min, etc., but not limited to the listed values. Other unlisted values within this value range are equally applicable.

[0052] As a preferred embodiment of the present invention, the processing temperature of the twin-screw extruder is 250°C - 270°C, such as 250°C, 255°C, 260°C, 265°C or 270°C, etc., but not limited to the listed values. Other unlisted values within this value range are equally applicable; the screw speed of the twin-screw extruder is 240 rpm - 360 rpm, such as 240 rpm, 260 rpm, 280 rpm, 300 rpm, 320 rpm, 340 rpm or 360 rpm, etc., but not limited to the listed values. Other unlisted values within this value range are equally applicable; the length of the material strip passing through water is 5 - 7 m, such as 5 m, 5.5 m, 6 m, 6.5 m or 7 m, etc., but not limited to the listed values. Other unlisted values within this value range are equally applicable; the water temperature is controlled at -5°C to 0°C, such as -5°C, -4°C, -3°C, -2°C, -1°C or 0°C, etc., but not limited to the listed values. Other unlisted values within this value range are equally applicable.

[0053] The following are typical but non-limiting examples of the present invention:

[0054] In the following examples, the PBT used (grade 1100 - 211S, Changchun Artificial Resin Factory Co., Ltd.); PET (grade KH2678C, Hengli Group - Yingkou Kanghui Petrochemical Co., Ltd.); EP (grade KD - 213, Guodu Chemical Industry (Kunshan) Co., Ltd.); lubricant (grade P130, Brüggemann); the antioxidant includes antioxidant 168 and antioxidant 1098 (BASF, Germany), and the mass ratio of antioxidant 168 to antioxidant 1098 is 1:1; glass fiber (chopped glass fiber, Taishan Glass Fiber Co., Ltd.); black dye (grade solvent black X70, Shanghai Runde Dye Chemical Co., Ltd.).

[0055] Example 1:

[0056] This embodiment provides a high laser transmittance PBT / PET / EP alloy and its preparation method. The alloy comprises components with the following weight percentage contents: PBT: 35%, PET: 24%, EP: 9%, lubricant: 0.3%, antioxidant: 0.4%, glass fiber: 30%, black dye: 1.3%.

[0057] The glass fiber is a modified chopped glass fiber processed by radio frequency magnetron sputtering using alumina as the target. The processing process of the modified chopped glass fiber is as follows: The chopped glass fiber is placed in a sodium hydroxide solution with a mass fraction of 3% to 5% for cleaning for 25 minutes, and then washed with clean water and put into a pretreatment agent with a mass fraction of 4%, stirred, and dried to obtain pretreated glass fiber; Using the pretreated glass fiber as the substrate and alumina as the target, radio frequency magnetron sputtering treatment is carried out to obtain the modified chopped glass fiber. When using alumina as the target in radio frequency magnetron sputtering, during the sputtering treatment, the sputtering pressure is controlled at 1.4 Pa, the sputtering power is 270 W, the sputtering time is 1.8 h, the vacuum degree is 4.5×10 -3 Pa, the argon gas flow rate is 35 ml / min, and the treated sample is annealed at 780 °C; The alumina is α-phase alumina, purchased from Fangyu Chemical's TAP-A26; The pretreatment agent is an aqueous solution of cyclohexylaminopropyltrimethoxysilane with a mass fraction of 3% - 5%.

[0058] The preparation method of the PBT / PET / EP alloy includes:

[0059] Weigh the formulated amounts of PBT, PET, EP, lubricant, antioxidant, glass fiber, and black dye and put them into a high-speed mixer for mixing and processing, discharging, and then extruding and pelletizing with a twin-screw extruder. The glass fiber is fed into the twin-screw extruder from the side feeding port, and the PBT / PET / EP alloy is obtained through extrusion and pelletizing. Among them, the mixing and processing time is 4 minutes, the processing temperature of the twin-screw extruder is 260 °C, the screw speed is 300 r / min; The length of the material strip passing through water is 6 m, and the water temperature is controlled at -3 °C.

[0060] Example 2:

[0061] This embodiment provides a high laser transmittance PBT / PET / EP alloy and its preparation method. The alloy comprises components with the following weight percentage contents: PBT: 33%, PET: 20%, EP: 6%, lubricant: 0.2%, antioxidant: 0.2%, glass fiber: 40%, black dye: 0.6%.

[0062] The processing process of the glass fiber is the same as that in Example 1.

[0063] The preparation method of the PBT / PET / EP alloy is the same as that in Example 1.

[0064] Example 3:

[0065] This example provides a PBT / PET / EP alloy with high laser transmittance and its preparation method. The alloy comprises components with the following weight percentages: PBT: 40%, PET: 23%, EP: 10%, lubricant: 0.3%, antioxidant: 0.3%, glass fiber: 25%, black dye: 1.4%.

[0066] The treatment process of the glass fiber is the same as that in Example 1.

[0067] The preparation method of the PBT / PET / EP alloy is the same as that in Example 1.

[0068] Comparative Example 1:

[0069] This comparative example provides a PBT / PET / EP alloy with high laser transmittance and its preparation method. The alloy comprises components with the following weight percentages: PBT: 39%, PET: 29%, lubricant: 0.3%, antioxidant: 0.4%, glass fiber: 30%, black dye: 1.3%.

[0070] The treatment process of the glass fiber is the same as that in Example 1.

[0071] The preparation method of the PBT / PET / EP alloy is the same as that in Example 1.

[0072] Comparative Example 2:

[0073] This comparative example provides a PBT / PET / EP alloy with high laser transmittance and its preparation method. The alloy comprises components with the following weight percentages: PBT: 35%, PET: 24%, EP: 9%, lubricant: 0.3%, antioxidant: 0.4%, glass fiber: 30%, black dye: 1.3%. The EP equivalent is 500 - 550 g / eq, purchased from KD - 211G of Guodu Chemical Industry (Kunshan) Co., Ltd.

[0074] The treatment process of the glass fiber is the same as that in Example 1.

[0075] The preparation method of the PBT / PET / EP alloy is the same as that in Example 1.

[0076] Comparative Example 3:

[0077] This comparative example provides a high laser transmittance PBT / PET / EP alloy and its preparation method. The alloy comprises the following components in percentage by weight: PBT: 35%, PET: 24%, EP: 9%, lubricant: 0.3%, antioxidant: 0.4%, glass fiber: 30%, black dye: 1.3%. The EP has an equivalent weight of 875 - 975 g / eq and is purchased as KD-214C from Guodu Chemical Industry (Kunshan) Co., Ltd.

[0078] The treatment process of the glass fiber is the same as that in Example 1.

[0079] The preparation method of the PBT / PET / EP alloy is the same as that in Example 1.

[0080] Comparative Example 4:

[0081] This comparative example provides a high laser transmittance PBT / PET / EP alloy and its preparation method. The alloy comprises the following components in percentage by weight: PBT: 35%, PET: 24%, EP: 9%, lubricant: 0.3%, antioxidant: 0.4%, glass fiber: 30%, black dye: 1.3%.

[0082] The treatment process of the glass fiber is the same as that in Example 1, except that the alumina is α-phase alumina with a particle size of 300 nm and is TAP-A30G from Fangyu Chemical Industry.

[0083] The preparation method of the PBT / PET / EP alloy is the same as that in Example 1.

[0084] Comparative Example 5:

[0085] This comparative example provides a high laser transmittance PBT / PET / EP alloy and its preparation method. The alloy comprises the following components in percentage by weight: PBT: 35%, PET: 24%, EP: 9%, lubricant: 0.3%, antioxidant: 0.4%, glass fiber: 30%, black dye: 1.3%.

[0086] The treatment process of the glass fiber is the same as that in Example 1, except that the alumina is α-phase alumina with a particle size of 30 nm and is VK-L30 from Xuancheng Jingrui New Materials Co., Ltd.

[0087] The preparation method of the PBT / PET / EP alloy is the same as that in Example 1.

[0088] Comparative Example 6:

[0089] This comparative example provides a high laser transmittance PBT / PET / EP alloy and its preparation method. The alloy comprises the following components in percentage by weight: PBT: 35%, PET: 24%, EP: 9%, lubricant: 0.3%, antioxidant: 0.4%, glass fiber: 30%, black dye: 1.3%.

[0090] The treatment process of the glass fiber is the same as that in Example 1, except that the alumina is γ-phase alumina with a particle size of 30 - 50 nm, SS-LY30 of Jikang New Materials.

[0091] The preparation method of the PBT / PET / EP alloy is the same as that in Example 1.

[0092] Comparative Example 7:

[0093] This comparative example provides a high laser transmittance PBT / PET / EP alloy and its preparation method. The alloy comprises the following components in percentage by weight: PBT: 35%, PET: 24%, EP: 9%, lubricant: 0.3%, antioxidant: 0.4%, glass fiber: 30%, black dye: 1.3%.

[0094] The treatment process of the glass fiber is the same as that in Example 1, except that the pretreatment agent is KH550.

[0095] The preparation method of the PBT / PET / EP alloy is the same as that in Example 1.

[0096] Comparative Example 8:

[0097] This comparative example provides a high laser transmittance PBT / PET / EP alloy and its preparation method. The alloy comprises the following components in percentage by weight: PBT: 35%, PET: 24%, EP: 9%, lubricant: 0.3%, antioxidant: 0.4%, glass fiber: 30%, black dye: 1.3%.

[0098] The treatment process of the glass fiber is the same as that in Example 1, except that the modified chopped glass fiber is not pretreated.

[0099] The preparation method of the PBT / PET / EP alloy is the same as that in Example 1.

[0100] Comparative Example 9:

[0101] This comparative example provides a high laser transmittance PBT / PET / EP alloy and its preparation method. The alloy comprises components with the following weight percentages: PBT: 35%, PET: 24%, EP: 9%, lubricant: 0.3%, antioxidant: 0.4%, glass fiber: 30%, black dye: 1.3%.

[0102] The treatment process of the glass fiber is the same as that in Example 1, except that the modified chopped glass fiber only undergoes pretreatment and does not undergo radio frequency magnetron sputtering treatment.

[0103] The preparation method of the PBT / PET / EP alloy is the same as that in Example 1.

[0104] Comparative Example 10:

[0105] This comparative example provides a high laser transmittance PBT / PET / EP alloy and its preparation method. The alloy comprises components with the following weight percentages: PBT: 35%, PET: 24%, EP: 9%, lubricant: 0.3%, antioxidant: 0.4%, glass fiber: 30%, black dye: 1.3%.

[0106] The treatment process of the glass fiber is the same as that in Example 1, except that the glass fiber does not undergo modification treatment, that is, neither pretreatment nor radio frequency magnetron sputtering treatment.

[0107] The preparation method of the PBT / PET / EP alloy is the same as that in Example 1.

[0108] The alloys prepared in Examples 1 - 3 and Comparative Examples 1 - 10 were subjected to performance testing. The testing method was the ISO standard. Among them, LPKF represents the transmittance of a 980 nm infrared laser passing through a 2.0 mm thick flat plate. The test results are shown in Tables 1 and 2 below.

[0109] Table 1: Test Results of the Alloy Performance in Examples 1 - 3

[0110]

[0111] Table 2: Test Results of the Alloy Performance in Comparative Examples 1 - 10

[0112]

[0113] As can be seen from the comparison in the above table, in Example 1 and Comparative Examples 1-3, when the EP addition amount is 0% or the equivalent content of EP is changed, it will affect the mechanical properties, temperature resistance and light transmittance of the alloy, especially the light transmittance performance. This may be because EP and its equivalent content affect the degree of chemical reaction and interfacial bonding force between PBT, PET and glass fiber, and the molecular network structure formed by them may lead to uneven distribution of local refractive index. However, it was unexpectedly found in the system of the present invention that only when the equivalent content of EP is controlled within 730-840 g / eq, a better interfacial bonding state can be constructed among PBT, PET, glass fiber and other components, significantly improving the comprehensive performance of the alloy.

[0114] Compared with Example 1, the particle size of α-phase alumina selected in Comparative Example 4 is 300 nm, the particle size of α-phase alumina selected in Comparative Example 5 is 30 nm, and the alumina selected in Comparative Example 6 is γ-phase alumina with a particle size of 30-50 nm, and the light transmittance of the alloy becomes worse. Particularly, when the particle size of α-phase alumina is 30 nm, it will also affect the mechanical properties and temperature resistance of the alloy material. This may be because smaller particle size is prone to agglomeration, on the one hand, increasing light scattering and absorption, and on the other hand, it is difficult to disperse evenly and easy to generate stress concentration points. When the alumina is γ-phase alumina, the influence on temperature resistance is obvious, which may be because the crystal stability decreases and it is easy to reduce the temperature resistance performance of the alloy material. In Comparative Example 9, when the glass fiber is not sputter-treated, it has a greater impact on the light transmittance, temperature resistance and mechanical properties of the alloy material, further demonstrating that the α-phase alumina with a particle size of 40-80 nm used in the present invention as the target for sputter-treating the glass fiber can not only significantly improve the interfacial bonding between the glass fiber and the PBT / PET / EP matrix, increase the transmittance of 980 nm infrared laser through a 2.0 mm thick flat plate, but also the mechanical properties and heat resistance of the material are better.

[0115] In Comparative Example 7, the pretreatment agent of the glass fiber was changed from cyclohexylaminopropyltrimethoxysilane to KH550. In Comparative Example 8, the glass fiber was not pretreated. In Comparative Example 10, the glass fiber was not modified, resulting in a decrease in light transmittance and a significant impact on the mechanical properties and heat resistance of the alloy material. This may be because cyclohexylaminopropyltrimethoxysilane has special steric hindrance and intermolecular forces in the system of the present invention, which can closely combine with the glass fiber and the alloy matrix, optimize the interface structure, strengthen stress transfer, and improve the mechanical properties of the alloy. Its stable interface also helps to maintain the material structure stability at high temperatures and enhance heat resistance. Moreover, using cyclohexylaminopropyltrimethoxysilane to pretreat the glass fiber can form a transition layer between the glass fiber and the sputtered film layer, which is beneficial to the occurrence of an interfacial reaction between the glass fiber and the sputtering material to form chemical bonds or alloy phases during sputtering, thereby further enhancing the bonding force between the glass fiber and the sputtered film layer and improving the overall performance of the alloy material.

[0116] In summary, by using a specific combination of PBT, PET, and EP and interacting with the glass fiber, lubricant, etc. in the system, the present invention achieves a light transmittance of 50% under the condition of a 2-mm thickness and a 980-nm laser. At the same time, the alloy also has good mechanical properties and heat resistance and can be used to manufacture, for example, the housing of an electromechanical actuator for vortex control.

[0117] The present invention uses the above embodiments to illustrate the detailed process equipment and process flow of the present invention. However, the present invention is not limited to the above detailed process equipment and process flow, that is, it does not mean that the present invention must rely on the above detailed process equipment and process flow to be implemented. Those skilled in the art should understand that any improvement to the present invention, the equivalent replacement of each raw material of the product of the present invention, the addition of auxiliary components, the selection of specific methods, etc. all fall within the protection scope and the disclosure scope of the present invention.

Claims

1. A PBT / PET / EP alloy with high laser transmittance, characterized in that: The alloy comprises the following raw material components in weight percentage: Polybutylene terephthalate 30%-40%; Polyethylene terephthalate 10%-30%; Epoxy resin 5%-10%; Lubricant 0.2%-0.5%; Antioxidant 0.2%-0.5%; Glass fiber 20%-40%; Black dye 0.5%-1.5%; The glass fiber is a modified short glass fiber that is treated by radio frequency magnetron sputtering with aluminum oxide as a target material; the treatment process of the modified short glass fiber is as follows: the short glass fiber is placed in a sodium hydroxide solution for cleaning, then washed with clean water, placed in a pretreatment agent, stirred, and dried to obtain the pretreated glass fiber; the pretreated glass fiber is used as a substrate and aluminum oxide is used as a target material to perform radio frequency magnetron sputtering to obtain the modified short glass fiber; the pretreatment agent is a cyclohexylaminopropyltrimethoxysilane aqueous solution with a mass fraction of 3%-5%; the epoxy resin, i.e., EP, is a bisphenol A type epoxy resin with an equivalent weight of 730-840 g / eq; the aluminum oxide is α-phase aluminum oxide with a particle size of 40-80nm.

2. The PBT / PET / EP alloy according to claim 1, characterized in that: The polybutylene terephthalate (PBT) has an intrinsic viscosity of 1.0±0.015 dl / g.

3. The PBT / PET / EP alloy according to claim 1, characterized in that: The polyethylene terephthalate, i.e. PET, has an intrinsic viscosity of 0.68±0.01 dl / g.

4. The PBT / PET / EP alloy according to claim 1, characterized in that: The lubricant is a mixture of a copolymer and wax in the form of beads or flakes.

5. The PBT / PET / EP alloy according to claim 1, characterized in that: The antioxidant is selected from one or a combination of antioxidant 1076, antioxidant 1010, antioxidant CA, antioxidant 2246, antioxidant 168, antioxidant 1098, and antioxidant 626.

6. The PBT / PET / EP alloy according to claim 1, characterized in that: The black dye is a chemical dye, and its chemical name is 2-sodium pyridyl-1,3-phenylenedihydrazine trisulfonate.

7. A method for preparing the PBT / PET / EP alloy according to any one of claims 1 to 6, characterized in that: The preparation method comprises: Weigh the formulated amounts of PBT, PET, EP, lubricant, antioxidant, glass fiber and black dye, put them into a high-speed mixer, mix and process, discharge, and then extrude and granulate them using a twin-screw extruder, wherein the glass fiber is fed into the twin-screw extruder from a side feed port, and the PBT / PET / EP alloy is obtained through extrusion and granulation.

8. The preparation method according to claim 7, characterized in that: The processing temperature of the twin-screw extruder is 250-270°C, the screw speed is 240-360 r / min; the length of the material strip passing through water is 5-7m, and the water temperature is controlled at -5°C~0°C.

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