High-flowability transfer-printable halogen-free flame-retardant glass fiber reinforced nylon composite material and preparation method thereof

Abstract

The invention relates to the technical field of nylon composite materials, in particular to a high-flowability transfer-printable halogen-free flame-retardant glass fiber reinforced nylon composite material and a preparation method thereof. The glass fiber reinforced nylon composite material is prepared from the following raw materials in percentage by weight: 20 to 40 percent of glass fiber grafted hyperbranched polymer, 8 to 12 percent of halogen-free flame retardant, 2 to 4 percent of flow modifier, 0.8 to 1.2 percent of nano boron nitride, 0.3 to 0.9 percent of transfer printing aid, 1 to 3 percent of flexibilizer, 0.1 to 1 percent of antioxidant and the balance of nylon resin. The flow modifier is low molecular weight polypropylene or a mixture of low molecular weight polyethylene, amino-terminated hyperbranched polyester and polyglycerol-3 polydimethylsilyl hydroxyethyl polydimethylsiloxane; the method has the advantage of improving the fluidity of the glass fiber reinforced nylon composite material.

Description

Technical Field

[0001] The present application relates to the technical field of nylon composites, and in particular to a high-flow, pad-printable, halogen-free flame-retardant glass fiber-reinforced nylon composite material and a preparation method thereof. Background Art

[0002] Glass fiber-reinforced nylon composites are widely used in fields such as automobiles, electronics, and electrical appliances due to their excellent mechanical properties, heat resistance, and processing properties. In recent years, with the development of automotive lightweighting and miniaturization of electronic devices, the comprehensive performance requirements for materials have become increasingly high. Although the addition of glass fiber can improve the mechanical properties and dimensional stability of nylon composites in many aspects, the addition of glass fiber also leads to a decrease in the fluidity of the material, and the appearance of the workpiece is prone to fiber floating phenomenon. In order to effectively reduce the fluidity of nylon composites, some technologies will reduce the molecular weight of the added nylon resin, but this also results in insufficient mechanical properties and is difficult to meet the requirements of some high-demand products. Summary of the Invention

[0003] In order to improve the fluidity of glass fiber-reinforced nylon composites, the present application provides a high-flow, pad-printable, halogen-free flame-retardant glass fiber-reinforced nylon composite material and a preparation method thereof.

[0004] In the first aspect, the present application provides a high-flow halogen-free flame-retardant glass fiber-reinforced nylon composite material, adopting the following technical solution: A high-flow, pad-printable, halogen-free flame-retardant glass fiber-reinforced nylon composite material, which comprises the following raw materials in weight percentage: 20-40% of glass fiber grafted hyperbranched polymer, 8-12% of halogen-free flame retardant, 2-4% of flow modifier, 0.8-1.2% of nano boron nitride, 0.3-0.9% of pad-printable additive, 1-3% of toughening agent, 0.1-1% of antioxidant, and the balance is nylon resin; The flow modifier is a mixture of low molecular weight polypropylene or low molecular weight polyethylene, amino-terminated hyperbranched polyester, and polyglycerol-3 polydimethylsiloxane hydroxyethyl polydimethylsiloxane, and the mass ratio thereof is 2:(0-3):(0-2), and the added masses of the amino-terminated hyperbranched polyester and polyglycerol-3 polydimethylsiloxane hydroxyethyl polydimethylsiloxane are not both 0 at the same time.

[0005] By adopting the above technical solutions, through grafting hyperbranched polymers on the surface of glass fibers, on the one hand, the distance between glass fibers can be increased, so that their dispersibility in the nylon matrix is improved. Moreover, the hyperbranched polymers on the molecular surface can reduce the viscosity between the glass fibers and the nylon matrix, improve the lubricity between them and the matrix, and enhance the fluidity of the material. Additionally, by compounding with flow modifiers, low molecular weight polyethylene or low molecular weight polypropylene, and polyglycerol-3 polydimethylsiloxane hydroxyethyl polydimethylsiloxane can all reduce the melt viscosity, and amino-terminated hyperbranched polyester can improve the dynamic lubricity among the raw materials of the system, thereby improving the fluidity of the material. Among them, the molecular structure of polyglycerol-3 polydimethylsiloxane hydroxyethyl polydimethylsiloxane contains a polyglycerol segment (hydrophilic part) and a polydimethylsiloxane segment (hydrophobic part). This amphiphilic property enables it to anchor on the surfaces of glass fibers and nano boron nitride, increasing the steric hindrance effect between particles, organizing the aggregation between particles, and at the same time being able to effectively reduce the interfacial tension between particles and the matrix, promoting their dispersion in the matrix. By improving the interaction between particles and reducing the internal frictional resistance, the viscosity of the system is thus reduced. In addition, when nano boron nitride is compounded with the flow modifier, the directional arrangement of its lamellar structure is used to guide the melt flow, and a continuous lubrication channel can be constructed in the system, thereby further improving the fluidity of the material.

[0006] Preferably, the preparation method of the glass fiber grafted with hyperbranched polymer is as follows: S1. Dissolve 2 - 3.5 g of hydroxy silane coupling agent in an ethanol / water mixed solution with a volume ratio of 1:1, then add 8 - 12 g of glass fiber, and stir and react at 65 - 80 °C for 20 - 26 h to obtain silane coupling agent modified glass fiber; S2. Disperse the prepared silane coupling agent modified glass fiber in a mixed solution of DMF and sulfolane with a volume ratio of 1:1, then add 0.08 - 0.12 mol of 4,4'-difluorodiphenyl sulfone and 0.25 - 0.4 mol of anhydrous potassium carbonate. After stirring, install a water separator, under a nitrogen atmosphere, heat up to 160 - 180 °C, stir and react, then continue to heat up to 200 - 220 °C, stir and react for 5 - 7 h, then add 0.1 - 0.15 mol of hydroxy-terminated hyperbranched polyester, continue to stir and react for 7 - 9 h, then filter, wash, and dry to obtain glass fiber grafted with hyperbranched polymer.

[0007] By adopting the above technical solutions, through the coupling of the hydroxy-containing silane coupling agent with the glass fiber, then the nucleophilic substitution reaction of 4,4'-difluorodiphenyl sulfone occurs, and then the nucleophilic substitution reaction with the hydroxy-terminated hyperbranched polyester is carried out to successfully graft the hyperbranched polymer. By using 4,4'-difluorodiphenyl sulfone as the intermediate connecting structure, the grafting effect can be good and the grafting rate can be high.

[0008] Preferably, the silane coupling agent is 3-[bis(2-hydroxyethyl)amino]propyltriethoxysilane.

[0009] By adopting the above technical solution, the silane coupling agent containing two hydroxyl groups has higher reactivity with 4,4'-difluorodiphenyl sulfone.

[0010] Preferably, the flow modifier is a mixture of low molecular weight polypropylene, amino-terminated hyperbranched polyester and polyglycerol-3 polydimethylsiloxane hydroxyethyl polydimethylsiloxane, and their mass ratio is 2:2:1.

[0011] By adopting the above technical solution, by optimizing the raw material ratio of the flow modifier, the fluidity of the material can be further improved, and the comprehensive performance is optimized.

[0012] Preferably, the average molecular weight of the low molecular weight polypropylene or low molecular weight polyethylene is 1000-10000.

[0013] By adopting the above technical solution, the low molecular weight polymer as an internal lubricant can effectively reduce the melt viscosity.

[0014] Preferably, the glass fiber reinforced nylon composite further includes 0.1-0.3% by weight of a silane coupling agent.

[0015] By adopting the above technical solution, the silane coupling agent here can mainly improve the compatibility between nano boron nitride and the matrix; and can also form a gradient interface with the hyperbranched polymer grafted on the glass fiber, reducing stress transfer loss.

[0016] Preferably, the silane coupling agent is one or more of N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane, anilinomethyltriethoxysilane, aminopropyltriethoxysilane 221, N-aminoethyl-γ-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane.

[0017] By adopting the above technical solution, by selecting an amino silane coupling agent, hydrogen bonds can be formed with the raw materials in the matrix, improving the compatibility between the raw materials.

[0018] Second, the present application provides a preparation method of a highly flowable, transferable, halogen-free flame-retardant glass fiber reinforced nylon composite, adopting the following technical solution: A preparation method of a highly flowable, transferable, halogen-free flame-retardant glass fiber reinforced nylon composite, which includes the following steps: S1. Premix the raw materials except the glass fiber grafted hyperbranched polymer to obtain a premix. S2. Add the premix to the main feeding port of a twin-screw extruder, and add the glass fiber grafted hyperbranched polymer through the side feeding port. S3. Control the extrusion temperature at 280 - 320 °C and the screw speed at 400 - 600 rpm, then extrude and pelletize to obtain a high-flow halogen-free flame-retardant glass fiber-reinforced nylon composite material.

[0019] By adopting the above technical solution, the melting points of the raw materials are matched to ensure sufficient melting while avoiding thermal damage to the glass fibers; the overall process of this application has strong parameter tolerance, and the modified glass fibers can be evenly dispersed in the system without additional dispersion means; moreover, the qualified rate of the prepared products is also high.

[0020] In summary, this application includes at least one of the following beneficial technical effects: 1. By grafting hyperbranched polymers on the surface of glass fibers, on the one hand, the distance between glass fibers can be increased, improving their dispersibility in the nylon matrix. And the hyperbranched polymers on the molecular surface can reduce the viscosity between the glass fibers and the nylon matrix, improving the lubricity between them and enhancing the fluidity of the material. Additionally, by compounding with flow modifiers, low molecular weight polyethylene or low molecular weight polypropylene, polyglycerol-3 polydimethylsiloxane hydroxyethyl polydimethylsiloxane can all reduce the melt viscosity, and amino-terminated hyperbranched polyester can improve the dynamic lubricity between the raw materials in the system, thereby improving the fluidity of the material. Among them, the molecular structure of polyglycerol-3 polydimethylsiloxane hydroxyethyl polydimethylsiloxane contains a polyglycerol segment (hydrophilic part) and a polydimethylsiloxane segment (hydrophobic part). This amphiphilicity enables it to anchor on the surfaces of glass fibers and nano-boron nitride, increasing the steric hindrance effect between particles, organizing the aggregation between particles, and at the same time effectively reducing the interfacial tension between particles and the matrix, promoting their dispersion in the matrix. By improving the interaction between particles and reducing the internal frictional resistance, the viscosity of the system is thus reduced. In addition, by compounding nano-boron nitride with flow modifiers and using the directional arrangement of its lamellar structure to guide the melt flow, a continuous lubrication channel can be constructed in the system, further improving the fluidity of the material.

[0021] 2. The tensile strength of the glass fiber-reinforced composite materials prepared in this application is between 161 - 244 MPa, the flexural strength is between 232 - 346 MPa, the Izod notched impact strength is between 20 - 33 KJ / m 2 ², the melt index is between 14.1 - 19.4 g / 10 min, and at the same time its spiral melt length is below 13.2 cm, with the minimum reaching 8.3 cm; indicating that the glass fiber-reinforced composite materials prepared in this application simultaneously possess excellent high-flow performance and mechanical properties. Detailed Embodiments

[0022] The following further elaborates on this application in detail in combination with specific content.

[0023] Raw Materials The raw materials used in the examples of the present application are all commercially available, among which the nylon resin PA6T is manufactured by Mitsui Chemicals of Japan; the manufacturer of PA9T is Kerila of Japan; the glass fiber is chopped glass fiber with a length of 3-6 mm and a diameter of 10-20 μm; the transfer printing auxiliary agent is amino-modified silicone oil, purchased from Wuhan Doer Ziguang New Technology Materials Co., Ltd., with a specification of QL-Q2219 and a viscosity of 8000 cst; the halogen-free flame retardant is ammonium polyphosphate, manufactured by Wuhan Xingzhongcheng Technology Co., Ltd.; the average molecular weight of low molecular weight polypropylene is 5000; the toughening agent is maleic anhydride grafted polyolefin elastomer, all purchased from Dongguan Shanyi Plastic Co., Ltd.; the antioxidant is a hindered amine light stabilizer, model UV-622; nano boron nitride is hexagonal boron nitride with a particle size of 100 nm, purchased from Shanghai Naio Nano Technology Co., Ltd.

[0024] Preparation Example Preparation Example 1 A glass fiber grafted hyperbranched polymer, the preparation method of which is as follows: S1. Dissolve 2.5 g of a silane coupling agent in 200 g of a mixed solution of ethanol and water in a volume ratio of 1:1, then add 10 g of glass fiber, and stir the mixture at 70° C. for 24 h to obtain silane coupling agent-modified glass fiber; the silane coupling agent is 3-[bis(2-hydroxyethyl)amino]propanetriethoxysilane; S2. Disperse the prepared silane coupling agent modified glass fiber in 1000g of a mixed solution of DMF and cyclopentane sulfone in a volume ratio of 1:1, then add 0.1mol of 4,4'-difluorodiphenyl sulfone and 0.3mol of anhydrous potassium carbonate, stir, install a water separator, heat to 170°C in a nitrogen atmosphere, stir and react for 2h, perform salt-forming reaction, then continue to heat to 200°C, stir and react for 6h, then add 0.11mol of terminal hydroxyl hyperbranched polyester, continue to stir and react for 8h, then filter, wash, and dry to obtain a glass fiber grafted hyperbranched polymer; wherein the relative molecular weight of the terminal hydroxyl hyperbranched polyester is 5200, and the model is HyPerH104. Example

[0025] Example 1 A high-flowable, transfer-printable, halogen-free, flame-retardant glass fiber reinforced nylon composite material, the raw materials and the amounts of the raw materials are shown in Table 1, and the preparation method is as follows: S1. Premixing the raw materials except the glass fiber grafted hyperbranched polymer according to the raw material ratio in Table 1 to obtain a premix; wherein the nylon resin is a mixture of PA6T and PA9T in a mass ratio of 3:2; the flow modifier is a mixture of low molecular weight polypropylene, amino-terminated hyperbranched polyester and polyglycerol-3 polydimethylsilyl hydroxyethyl polydimethylsiloxane in a mass ratio of 2:2:1; S2. Add the premix to the main feeding port of the twin-screw extruder, and add the glass fiber grafted hyperbranched polymer through the side feeding port; among them, the glass fiber grafted hyperbranched polymer is prepared according to Preparation Example 1. S3. Control the extrusion temperature at 300 °C and the screw speed at 400 - 600 rpm, and then extrude and pelletize to obtain a high-flow halogen-free flame-retardant glass fiber-reinforced nylon composite material.

[0026] Table 1 Raw materials and dosages of each raw material in Example 1 (kg) Nylon resin Make up to 100 Glass fiber grafted hyperbranched polymer 20 Halogen-free flame retardant 10 Flow modifier 3 Nanoscale boron nitride 1 Pad printing auxiliary 0.6 Toughening agent 2 Antioxidant 0.5 Example 2 A high-flow printable halogen-free flame-retardant glass fiber-reinforced nylon composite material, which is different from Example 1 in that its raw materials also include 0.2 kg of silane coupling agent KH550, and the remaining steps are the same as those in Example 1.

[0027] Example 3 A high-flow printable halogen-free flame-retardant glass fiber-reinforced nylon composite material, which is different from Example 2 in that the addition amount of the glass fiber grafted hyperbranched polymer is 30 kg, and the remaining steps are the same as those in Example 2.

[0028] Example 4 A high-flow printable halogen-free flame-retardant glass fiber-reinforced nylon composite material, which is different from Example 2 in that the addition amount of the glass fiber grafted hyperbranched polymer is 40 kg, and the remaining steps are the same as those in Example 2.

[0029] Example 5 A high-flow printable halogen-free flame-retardant glass fiber-reinforced nylon composite material, which is different from Example 2 in that the terminal amino hyperbranched polyester is not added to the flow modifier, and the remaining steps are the same as those in Example 2.

[0030] Example 6 A high-flow printable halogen-free flame-retardant glass fiber-reinforced nylon composite material, which is different from Example 2 in that the polyglycerol-3 polydimethylsiloxane hydroxyethyl polydimethylsiloxane is not added to the flow modifier, and the remaining steps are the same as those in Example 2.

[0031] Comparative Example Comparative Example 1 A high-flow printable halogen-free flame-retardant glass fiber-reinforced nylon composite material, which is different from Example 1 in that the flow modifier is small molecule polyethylene, and the remaining steps are the same as those in Example 1.

[0032] Comparative Example 2 A high-flow printable halogen-free flame-retardant glass fiber-reinforced nylon composite, which is different from Example 1 in that the glass fiber grafted with hyperbranched polymer is replaced with glass fiber modified by an equal mass of silane coupling agent. The glass fiber modified by silane coupling agent is prepared by the S1 step of Preparation Example 1, and the remaining steps are the same as those in Example 1.

[0033] Comparative Example 3 A high-flow printable halogen-free flame-retardant glass fiber-reinforced nylon composite, which is different from Example 1 in that nano boron nitride is not added to its raw materials, and the remaining steps are the same as those in Example 1.

[0034] Performance detection test Detection method / Test method Prepare glass fiber-reinforced nylon composites according to the preparation methods of Examples 1-6 and Comparative Examples 1-3 respectively, and then detect them according to the following detection methods. The detection results are shown in Table 2.

[0035] Tensile strength: Detect according to the detection method in ISO 527; Flexural strength: Detect according to the detection method in ISO 178; Izod notched impact strength: Detect according to the detection method in ISO 178; Melt index: Detect according to the detection method in ISO 1133, test conditions: 275 °C, 2.16 kg; Spiral melt length: By fixing the injection molding process, compare the lengths of injection molded samples.

[0036] Table 2 Detection results of Examples 1-6 and Comparative Examples 1-3 It can be seen from Examples 1-6, Comparative Examples 1-3 and the detection data in Table 2 that the tensile strength of the glass fiber-reinforced composite prepared in this application is between 161-244 MPa, the flexural strength is between 232-346 MPa, and the Izod notched impact strength is between 20-33 KJ / m 2 between, the melt index is between 14.1-19.4 g / 10 min, and at the same time its spiral melt length is below 13.2 cm, and the minimum can reach 8.3 cm; it shows that the glass fiber-reinforced composite prepared in this application has excellent high-flow performance and mechanical properties at the same time.

[0037] By grafting hyperbranched polymers onto the surface of glass fibers, on the one hand, the spacing between glass fibers can be increased, improving their dispersion in the nylon matrix. Moreover, the hyperbranched polymers on the molecular surface can reduce the viscosity between the glass fibers and the nylon matrix, enhancing the lubricity between them and strengthening the fluidity of the material. This can be verified by the test data of Example 1 and Comparative Example 2.

[0038] In addition, when compounding flow modifiers, low molecular weight polyethylene or low molecular weight polypropylene, polyglycerol-3 dimethylsilyl hydroxyethyl dimethyl polysiloxane can all reduce the melt viscosity, and amino-terminated hyperbranched polyester can improve the dynamic lubricity between the raw materials of the system, thereby enhancing the fluidity of the material. Among them, the molecular structure of polyglycerol-3 dimethylsilyl hydroxyethyl dimethyl polysiloxane contains a polyglycerol segment (hydrophilic part) and a dimethyl polysiloxane segment (hydrophobic part). This amphiphilic property enables it to anchor on the surfaces of glass fibers and nano boron nitride, increasing the steric hindrance effect between particles, preventing particle aggregation, and at the same time effectively reducing the interfacial tension between particles and the matrix, promoting their dispersion in the matrix. By improving the interaction between particles and reducing the internal friction resistance, the viscosity of the system is reduced. This can be verified by the test data of Example 2 and Comparative Example 1. On this basis, combined with Examples 5-6, it can be seen that there is a synergistic effect between polyglycerol-3 dimethylsilyl hydroxyethyl dimethyl polysiloxane and amino-terminated hyperbranched polyester in the compound flow modifier in improving the fluidity of the system.

[0039] In addition, when nano boron nitride is compounded with a flow modifier, its lamellar structure's oriented arrangement guides the melt flow, enabling the formation of continuous lubrication channels in the system, thereby further enhancing the fluidity of the material. This can be verified by the test data of Example 1 and Comparative Example 3. And combined with Example 2, here the silane coupling agent can mainly improve the compatibility between nano boron nitride and the matrix; and it can also form a gradient interface with the hyperbranched polymer grafted on the glass fiber, reducing stress transfer loss, which can further improve the fluidity and mechanical properties of the material.

[0040] Through Examples 2-4, when the addition amount of the hyperbranched polymer grafted on the glass fiber gradually increases, the mechanical properties of the glass fiber reinforced nylon material gradually improve, but its melt index and spiral melt length also increase; therefore, according to the actual usage requirements, the addition amount of the hyperbranched polymer grafted on the glass fiber can be selected.

[0041] This specific embodiment is only an explanation of the present invention and is not a limitation thereof. Those skilled in the art can make modifications to this embodiment without creative contributions after reading this specification, but as long as it is within the scope of the claims of the present invention, it is protected by the patent law.

Claims

1. A high-flow transfer printing halogen-free flame-retardant glass fiber-reinforced nylon composite material, characterized in that: It comprises raw materials with the following weight percentages: 20-40% of glass fiber grafted hyperbranched polymer, 8-12% of halogen-free flame retardant, 2-4% of flow modifier, 0.8-1.2% of nano boron nitride, 0.3-0.9% of pad-printing auxiliary, 1-3% of toughening agent, 0.1-1% of antioxidant, and the balance is nylon resin; The flow modifier is a mixture of low molecular weight polypropylene or low molecular weight polyethylene, amino-terminated hyperbranched polyester and polyglycerol-3 dimethylsilyl hydroxyethyl polydimethylsiloxane, and their mass ratio is 2:(0-3):(0-2), and the added masses of the amino-terminated hyperbranched polyester and polyglycerol-3 dimethylsilyl hydroxyethyl polydimethylsiloxane are not both 0 at the same time.

2. A highly flowable pad-printable halogen-free flame-retardant glass fiber-reinforced nylon composite material according to claim 1, wherein: The preparation method of the glass fiber grafted hyperbranched polymer is as follows: S1. Dissolve 2-3.5 g of hydroxy silane coupling agent in an ethanol / water mixed solution with a volume ratio of 1:1, then add 8-12 g of glass fiber, and stir and react at 65-80 °C for 20-26 h to obtain silane coupling agent modified glass fiber; S2. Disperse the prepared silane coupling agent modified glass fiber in a mixed solution of DMF and sulfolane with a volume ratio of 1:1, then add 0.08-0.12 mol of 4,4'-difluorodiphenyl sulfone and 0.25-0.4 mol of anhydrous potassium carbonate, stir, install a water separator, under a nitrogen atmosphere, heat up to 160-180 °C, stir and react, then continue to heat up to 200-220 °C, stir and react for 5-7 h, then add 0.1-0.15 mol of hydroxy-terminated hyperbranched polyester, continue to stir and react for 7-9 h, then filter, wash, and dry to obtain the glass fiber grafted hyperbranched polymer.

3. A highly flowable pad-printable halogen-free flame-retardant glass fiber-reinforced nylon composite material according to claim 2, wherein: The silane coupling agent is 3-[bis(2-hydroxyethyl)amino]propane triethoxysilane.

4. A highly flowable pad-printable halogen-free flame-retardant glass fiber-reinforced nylon composite material according to claim 1, characterized in that: The flow modifier is a mixture of low molecular weight polypropylene, amino-terminated hyperbranched polyester and polyglycerol-3 dimethylsilyl hydroxyethyl polydimethylsiloxane, and their mass ratio is 2:2:

1.

5. A high-flowable, pad-printable, halogen-free flame-retardant glass fiber-reinforced nylon composite according to claim 1, wherein: The average molecular weight of the low molecular weight polypropylene or low molecular weight polyethylene is 1000-10000.

6. The high-flowable pad-printable halogen-free flame-retardant glass fiber-reinforced nylon composite material according to claim 1, wherein: The glass fiber reinforced nylon composite material also comprises 0.1-0.3% of silane coupling agent by weight percentage.

7. A high-flowable pad-printable halogen-free flame-retardant glass fiber-reinforced nylon composite material according to claim 6, characterized in that: The silane coupling agent is one or more of N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane, anilinomethyltriethoxysilane, aminopropyltriethoxysilane 221, N-aminoethyl-γ-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane.

8. A method for preparing the high-flow pad-printable halogen-free flame-retardant glass fiber-reinforced nylon composite material according to any one of claims 1-7, characterized in that: It comprises the following steps: S1. Premix the raw materials except the glass fiber grafted hyperbranched polymer to obtain a premix; S2. Add the premix to the main feeding port of a twin-screw extruder, and add the glass fiber grafted hyperbranched polymer through the side feeding port; S3. Control the extrusion temperature at 280-320 °C and the screw speed at 400-600 rpm, then extrude and pelletize to obtain a high-flow pad-printable halogen-free flame-retardant glass fiber reinforced nylon composite material.

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