Flame-retardant nylon composite material, preparation method and application thereof

Abstract

This invention discloses a flame-retardant nylon composite material, its preparation method, and its applications. The raw materials for preparing the flame-retardant nylon composite material include: nylon resin, 1,4-bis(diphenoxyphosphoryl)piperazine, polyphenylene benzodioxazole, heterocyclic aramid, and glass fiber. The preparation method includes: compounding a mixture containing nylon resin, 1,4-bis(diphenoxyphosphoryl)piperazine, polyphenylene benzodioxazole chopped fibers, heterocyclic aramid chopped fibers, antioxidant, lubricant, and nucleating agent with glass fiber to obtain the flame-retardant nylon composite material. The flame-retardant nylon composite material possesses both excellent flame-retardant and mechanical properties, and can be effectively applied in the fields of automotive, electronics, aerospace, and defense technologies.

Description

Technical Field

[0001] This invention belongs to the field of nylon preparation technology, specifically relating to a flame-retardant nylon composite material, its preparation method, and its application. Background Technology

[0002] Polyamide, commonly known as nylon, is a general term for polymers whose main molecular chain repeating units contain amide groups. Nylon has excellent comprehensive properties, including mechanical properties, heat resistance, wear resistance, chemical resistance, and self-lubricating properties. It also has a low coefficient of friction, some flame retardancy, and is easy to process. It is suitable for reinforcement and modification with glass fiber and other fillers to improve performance and expand its application range.

[0003] Flame-retardant nylon materials possess excellent flame-retardant properties, superior mechanical properties, outstanding electrical insulation properties, good heat resistance and stability, flexibility in product development, and cost controllability. They are widely used in almost all industrial power engineering, electronic products, and home appliance technologies. While nylon materials have a UL94 V-2 flammability rating and some flame-retardant properties, with the continuous expansion of their applications, the electronics, electrical appliances, and construction industries are placing higher demands on the flame-retardant performance of nylon, requiring a vertical flammability rating of UL94 V-0.

[0004] Existing technologies CN1 17820852A, CN1061 18045A, CN1 15850962A, CN1 11349334A, CN118791869A, and CN104693793A disclose various methods for preparing flame-retardant nylon composite materials. However, the current technology has the problem of high flame retardant content and the reduction of material mechanical properties by the addition of flame retardants. Therefore, selecting appropriate flame retardants and formulation processes, and how to maintain the flame retardancy and mechanical properties of composite materials are the directions for future development. Summary of the Invention

[0005] The main objective of this invention is to provide a flame-retardant nylon composite material, its preparation method, and its application, in order to overcome the shortcomings of the prior art.

[0006] To achieve the aforementioned objectives, the technical solution adopted by this invention includes:

[0007] One aspect of the present invention provides a flame-retardant nylon composite material, wherein the raw materials for preparing the flame-retardant nylon composite material include: nylon resin, 1,4-bis(diphenoxyphosphoryl)piperazine, polyphenylenebenzodioxazole, heterocyclic aramid, and glass fiber.

[0008] Furthermore, the raw materials for preparing the flame-retardant nylon composite material include: nylon resin, 1,4-bis(diphenoxyphosphoryl)piperazine, polyphenylene benzodioxazole chopped fibers, heterocyclic aramid chopped fibers, glass fiber, antioxidant, lubricant, and nucleating agent.

[0009] Another aspect of the present invention provides a method for preparing the flame-retardant nylon composite material, comprising: compounding a mixture comprising nylon resin, 1,4-bis(diphenoxyphosphoryl)piperazine, polyphenylene benzodioxazole chopped fibers, heterocyclic aramid chopped fibers, antioxidant, lubricant, and nucleating agent with glass fiber to obtain the flame-retardant nylon composite material.

[0010] Another aspect of the present invention provides the application of the flame-retardant nylon composite material in the fields of automotive, electronics, aerospace, and defense technologies.

[0011] Compared with the prior art, the present invention has at least the following beneficial effects:

[0012] Polyphenylene benzodioxazole chopped fibers and heterocyclic aramid chopped fibers, as intrinsic flame-retardant fibers, have higher strength than glass fibers. Introducing these two fibers can, on the one hand, reduce the amount of flame retardant 1,4-bis(diphenoxyphosphoryl)piperazine added, thereby reducing the degree of decline in the mechanical properties of the composite material; on the other hand, it can improve the mechanical properties and flame retardancy of the composite material. The flame-retardant nylon composite material prepared by these fibers has both excellent flame retardant and mechanical properties. Detailed Implementation

[0013] In view of the problems existing in the prior art, the inventors of this invention have conducted extensive and in-depth research and have provided a flame-retardant nylon composite material, its preparation method and application. The main process involves mixing nylon resin, 1,4-bis(diphenoxyphosphoryl)piperazine, polyphenylene benzodioxazole chopped fibers, heterocyclic aramid chopped fibers, antioxidants, lubricants and nucleating agents, and then compounding them with glass fibers through a twin-screw extrusion process to obtain the flame-retardant nylon composite material.

[0014] The following will provide a further explanation of the technical solution, its implementation process, and its principles.

[0015] As one aspect of the technical solution of the present invention, it provides a flame-retardant nylon composite material, wherein the raw materials for preparing the flame-retardant nylon composite material include: nylon resin, 1,4-bis(diphenoxyphosphoryl)piperazine, polyphenylenebenzodioxazole, heterocyclic aramid and glass fiber.

[0016] In some embodiments, the raw materials for preparing the flame-retardant nylon composite material include: nylon resin, 1,4-bis(diphenoxyphosphoryl)piperazine, polyphenylene benzodioxazole chopped fibers, heterocyclic aramid chopped fibers, glass fiber, antioxidant, lubricant, and nucleating agent.

[0017] In some embodiments, the raw materials for preparing the flame-retardant nylon composite material include the following components by weight percentage: 30%–70% nylon resin, 3%–6% 1,4-bis(diphenoxyphosphoryl)piperazine, 1%–5% polyphenylene benzodioxazole chopped fibers, 1%–5% heterocyclic aramid chopped fibers, 20%–60% glass fiber, 0.1%–1% antioxidant, 0.1%–1% lubricant, and 0.1%–1% nucleating agent.

[0018] In some embodiments, the length of the polyphenylene benzodioxazole chopped fibers is 3-7 mm and the diameter of the monofilament is 5-15 μm.

[0019] In some embodiments, the length of the heterocyclic aramid chopped fibers is 3-7 mm, and the diameter of the monofilament is 5-15 μm.

[0020] Specifically, the chemical structural formula of 1,4-bis(diphenoxyphosphoryl)piperazine (PDPCP) is as follows:

[0021]

[0022] Flame retardant PDPCP belongs to the organic nitrogen-phosphorus heterocyclic compound family. It has excellent flame retardant efficiency, good heat resistance, and can withstand higher processing temperatures. Polymer composites with a small amount of PDPCP exhibit excellent flame retardant properties and high flame retardant efficiency. The PCN bond structure can promote char formation and provides excellent thermal stability.

[0023] The chemical structural formula of polyphenylenebenzodioxazole (PBO) is as follows:

[0024]

[0025] Poly(phenylene oxide) (PBO) is currently considered the best-performing organic fiber, often referred to as the "super fiber of the 21st century." The coplanar and highly conjugated benzene and oxazole rings in its molecular backbone endow PBO with extremely high specific strength, specific modulus, heat resistance, and flame retardancy. Its tensile strength reaches 5.8 GPa, and its tensile modulus is 280 GPa, approximately twice that of para-aramid, exceeding that of steel fiber and surpassing even carbon fiber. PBO fiber has a limiting oxygen index (LOI) of 68, the highest among organic fibers. PBO fiber has no melting point and does not melt at high temperatures, with a thermal decomposition temperature as high as 650℃.

[0026] The chemical structural formula of heterocyclic aramid is as follows:

[0027]

[0028] Heterocyclic aramid, also known as aramid III or heterocyclic aromatic polyamide fiber, refers to high-performance fibers made by introducing heterocyclic structural units into the traditional aramid structure. The heterocyclic structure of aramid III gives it ultra-high strength and ultra-high modulus, and it also has excellent properties in terms of high temperature resistance, impact resistance, wear resistance, and wave transmission. Furthermore, it is more conducive to the composite of fibers and resins.

[0029] In some embodiments, the nylon resin includes any one or more of nylon 66 resin, nylon 6 resin, nylon 6T resin, nylon 10T, etc., but is not limited thereto.

[0030] In some embodiments, the antioxidant includes any one or a combination of two or more of antioxidants such as 1098, H161, and 168, but is not limited thereto.

[0031] In some embodiments, the lubricant includes silicone-based lubricants.

[0032] In some embodiments, the nucleating agent includes any one or a combination of two or more of nano-montmorillonite, fine talc powder, boron nitride, etc., but is not limited thereto.

[0033] In some embodiments, the flame retardant properties of the nylon flame retardant composite material are V0.

[0034] In some embodiments, the tensile strength of the nylon flame-retardant composite material is 100–250 MPa.

[0035] In some embodiments, the flexural strength of the nylon flame-retardant composite material is 150–300 MPa.

[0036] In some embodiments, the flexural modulus of the nylon flame-retardant composite material is 8000–15000 MPa.

[0037] In some embodiments, the unnotched impact strength of the simply supported beam of the nylon flame-retardant composite material is 30–100 kJ / m. 2 .

[0038] In some embodiments, the notched impact strength of the simply supported beam of the nylon flame-retardant composite material is 3–10 kJ / m. 2 .

[0039] As another aspect of the technical solution of the present invention, a method for preparing a flame-retardant nylon composite material is provided, comprising: compounding a mixture containing nylon resin, 1,4-bis(diphenoxyphosphoryl)piperazine, polyphenylene benzodioxazole chopped fibers, heterocyclic aramid chopped fibers, antioxidant, lubricant, and nucleating agent with glass fiber to prepare the flame-retardant nylon composite material.

[0040] In some more specific embodiments, the preparation method specifically includes: vacuum drying a mixture containing nylon resin, 1,4-bis(diphenoxyphosphoryl)piperazine, polyphenylene benzodioxazole chopped fibers, heterocyclic aramid chopped fibers, antioxidant, lubricant, and nucleating agent at 100-120°C for 6-12 hours to obtain a mixture.

[0041] In some more specific embodiments, the preparation method further includes: compounding the mixture with glass fiber through a twin-screw extrusion process to obtain the flame-retardant nylon composite material.

[0042] In some more specific embodiments, the preparation method may include the following steps:

[0043] (1) Nylon resin, 1,4-bis(diphenoxyphosphoryl)piperazine, polyphenylene benzodioxazole short chopped fiber, heterocyclic aramid short chopped fiber, antioxidant, lubricant and nucleating agent are mixed evenly, and then vacuum dried at 100-120℃ for 6-12h to obtain the mixture.

[0044] (2) The mixture is fed through the main feed port of the twin-screw extruder, and the glass fiber is fed through the side feed port of the twin-screw extruder. After the twin-screw extruder melts, mixes, extrudes, cools, dries and pelletizes, flame-retardant nylon composite material is obtained.

[0045] As another aspect of the technical solution of the present invention, the application of the flame-retardant nylon composite material in the fields of automobiles, electronics and electrical engineering, aerospace, and defense and military technology is also provided.

[0046] In some preferred embodiments, the flame-retardant nylon composite material is used in automotive or electrical / electronic applications.

[0047] In summary, this invention involves uniformly mixing nylon resin, 1,4-bis(diphenoxyphosphoryl)piperazine, polyphenylene benzodioxazole chopped fibers, heterocyclic aramid chopped fibers, antioxidants, lubricants, and nucleating agents, and then combining them with glass fibers via a twin-screw extrusion process to prepare the flame-retardant nylon composite material. This composite material possesses both excellent flame-retardant properties and mechanical properties.

[0048] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments and comparative examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. Modifications or equivalent substitutions made by those skilled in the art based on their understanding of the technical solutions of this invention, without departing from the spirit and scope of the invention, should all be covered within the protection scope of this invention.

[0049] For experiments not specifically described in the examples, the procedures or conditions can be performed according to conventional experimental procedures described in the literature in this field. Reagents or instruments whose manufacturers are not specified are all commercially available conventional reagent products. Other unmentioned raw materials and instruments are all conventionally selected and do not involve the core technical means of this invention.

[0050] Specifically, the testing method used in this invention is as follows:

[0051] (1) Mechanical properties

[0052] The prepared flame-retardant nylon composite injection molding test strips were tested for tensile strength according to GB / T1040.2 standard, flexural strength and flexural modulus according to GB / T9341-2008 standard, and simply supported beam impact strength according to GB / T1043.1 standard.

[0053] (2) Flame retardant properties

[0054] Flame retardancy was tested using a 1.6 mm thick sample strip conditioned at 23°C and 50% relative humidity for 96 hours according to standard UL94:2014.

[0055] Example 1

[0056] Weigh out 53.5% nylon 66 resin, 4% PDPCP, 3% PBO chopped short fibers (6mm), 3% heterocyclic aramid chopped short fibers (6mm), 0.5% antioxidant 1098, 0.5% silicone powder, and 0.5% fine talc powder by weight percentage. After dispersion and mixing in a high-speed mixer, add the mixture through the main feed inlet. Add 35% glass fiber through the side feed inlet. The mixture is then melted, mixed, extruded, cooled, dried, and pelletized using a twin-screw extruder. The extrusion temperature of the twin-screw extruder is 260-280℃, the main extruder speed is 200-350 rpm / min, and the screw length-to-diameter ratio is 40:1. After injection molding, the product is tested according to standards. Product performance tests are shown in Table 1.

[0057] Example 2

[0058] Weigh out 53.5% nylon 6 resin, 4% PDPCP, 3% PBO chopped short fibers (6mm), 3% heterocyclic aramid chopped short fibers (6mm), 0.5% antioxidant 1098, 0.5% silicone powder, and 0.5% fine talc powder by weight percentage. After dispersion and mixing in a high-speed mixer, add the mixture through the main feed inlet. Add 35% glass fiber through the side feed inlet. The mixture is then melted, mixed, extruded, cooled, dried, and pelletized using a twin-screw extruder. The extrusion temperature of the twin-screw extruder is 220-235℃, the main extruder speed is 200-350 rpm / min, and the screw length-to-diameter ratio is 40:1. After injection molding, the product is tested according to standards. Product performance test results are shown in Table 1.

[0059] Example 3

[0060] Weigh out 53.5% nylon 6T / 66 resin, 4% PDPCP, 3% PBO chopped short fibers (6mm), 3% heterocyclic aramid chopped short fibers (6mm), 0.5% antioxidant 1098, 0.5% silicone powder, and 0.5% fine talc powder by weight percentage. After dispersion and mixing in a high-speed mixer, add the mixture through the main feed inlet. Add 35% glass fiber through the side feed inlet. The mixture is then melted, mixed, extruded, cooled, dried, and pelletized using a twin-screw extruder. The extrusion temperature of the twin-screw extruder is 300-315℃, the main extruder speed is 200-350 rpm / min, and the screw length-to-diameter ratio is 40:1. After injection molding, the product is tested according to standards. Product performance tests are shown in Table 1.

[0061] Example 4

[0062] Weigh out 53.5% nylon 10T resin, 4% PDPCP, 3% PBO chopped short fibers (6mm), 3% heterocyclic aramid chopped short fibers (6mm), 0.5% antioxidant 1098, 0.5% silicone powder, and 0.5% fine talc powder by weight percentage. After dispersion and mixing in a high-speed mixer, add the mixture through the main feed inlet. Add 35% glass fiber through the side feed inlet. The mixture is then melted, mixed, extruded, cooled, dried, and pelletized using a twin-screw extruder. The extrusion temperature of the twin-screw extruder is 300-315℃, the main extruder speed is 200-350 rpm / min, and the screw length-to-diameter ratio is 40:1. After injection molding, the product is tested according to standards. Product performance tests are shown in Table 1.

[0063] Example 5

[0064] Weigh out 53.5% nylon 6T / 6 resin, 4% PDPCP, 3% PBO chopped short fibers (6mm), 3% heterocyclic aramid chopped short fibers (6mm), 0.5% antioxidant 1098, 0.5% silicone powder, and 0.5% fine talc powder by weight percentage. After dispersion and mixing in a high-speed mixer, add the mixture through the main feed inlet. Add 35% glass fiber through the side feed inlet. The mixture is then melted, mixed, extruded, cooled, dried, and pelletized using a twin-screw extruder. The extrusion temperature of the twin-screw extruder is 260-280℃, the main extruder speed is 200-350 rpm / min, and the screw length-to-diameter ratio is 40:1. After injection molding, the product is tested according to standards. Product performance tests are shown in Table 1.

[0065] Example 6

[0066] Weigh out 51.5% nylon 66 resin, 6% PDPCP, 5% PBO chopped short fibers (6mm), 5% heterocyclic aramid chopped short fibers (6mm), 0.5% antioxidant 1098, 0.5% silicone powder, and 0.5% fine talc powder by weight percentage. After dispersion and mixing in a high-speed mixer, add the mixture through the main feed inlet. Add 31% glass fiber through the side feed inlet. The mixture is then melted, mixed, extruded, cooled, dried, and pelletized using a twin-screw extruder. The extrusion temperature of the twin-screw extruder is 260-280℃, the main extruder speed is 200-350 rpm / min, and the screw length-to-diameter ratio is 40:1. After injection molding, the product is tested according to standards. Product performance tests are shown in Table 1.

[0067] Example 7

[0068] Weigh out 54.5% nylon 66 resin, 3% PDPCP, 1% PBO chopped short fibers (6mm), 1% heterocyclic aramid chopped short fibers (6mm), 0.5% antioxidant 1098, 0.5% silicone powder, and 0.5% fine talc powder by weight percentage. After dispersion and mixing in a high-speed mixer, add the mixture through the main feed inlet. Add 39% glass fiber through the side feed inlet. The mixture is then melted, mixed, extruded, cooled, dried, and pelletized using a twin-screw extruder. The extrusion temperature of the twin-screw extruder is 260-280℃, the main extruder speed is 200-350 rpm / min, and the screw length-to-diameter ratio is 40:1. After injection molding, the product is tested according to standards. Product performance tests are shown in Table 1.

[0069] Example 8

[0070] Weigh out 54.5% nylon 66 resin, 3% PDPCP, 5% PBO chopped short fibers (6mm), 5% heterocyclic aramid chopped short fibers (6mm), 0.5% antioxidant 1098, 0.5% silicone powder, and 0.5% fine talc powder by weight percentage. After dispersion and mixing in a high-speed mixer, add the mixture through the main feed inlet. Add 31% glass fiber through the side feed inlet. The mixture is then melted, mixed, extruded, cooled, dried, and pelletized using a twin-screw extruder. The extrusion temperature of the twin-screw extruder is 260-280℃, the main extruder speed is 200-350 rpm / min, and the screw length-to-diameter ratio is 40:1. After injection molding, the product is tested according to standards. Product performance tests are shown in Table 1.

[0071] Example 9

[0072] Weigh out 51.5% nylon 66 resin, 6% PDPCP, 1% PBO chopped short fibers (6mm), 1% heterocyclic aramid chopped short fibers (6mm), 0.5% antioxidant 1098, 0.5% silicone powder, and 0.5% fine talc powder by weight percentage. After dispersion and mixing in a high-speed mixer, add the mixture through the main feed inlet. Add 39% glass fiber through the side feed inlet. The mixture is then melted, mixed, extruded, cooled, dried, and pelletized using a twin-screw extruder. The extrusion temperature of the twin-screw extruder is 260-280℃, the main extruder speed is 200-350 rpm / min, and the screw length-to-diameter ratio is 40:1. After injection molding, the product is tested according to standards. Product performance tests are shown in Table 1.

[0073] Example 10

[0074] Weigh out 30% nylon 66 resin, 4% PDPCP, 3% PBO chopped short fibers (6mm), 3% heterocyclic aramid chopped short fibers (6mm), 0.5% antioxidant 1098, 0.5% silicone powder, and 0.5% fine talc powder by weight percentage. After dispersion and mixing in a high-speed mixer, add the mixture through the main feed inlet. Add 58.5% glass fiber through the side feed inlet. The mixture is then melted, mixed, extruded, cooled, dried, and pelletized using a twin-screw extruder. The extrusion temperature of the twin-screw extruder is 260-280℃, the main extruder speed is 200-350 rpm / min, and the screw length-to-diameter ratio is 40:1. After injection molding, the product is tested according to standards. Product performance tests are shown in Table 1.

[0075] Example 11

[0076] Weigh out 70% nylon 66 resin, 4% PDPCP, 3% PBO chopped short fibers (6mm), 3% heterocyclic aramid chopped short fibers (6mm), 0.5% antioxidant 1098, 0.5% silicone powder, and 0.5% fine talc powder by weight percentage. After dispersion and mixing in a high-speed mixer, add the mixture through the main feed inlet. Add 18.5% glass fiber through the side feed inlet. The mixture is then melted, mixed, extruded, cooled, dried, and pelletized using a twin-screw extruder. The extrusion temperature of the twin-screw extruder is 260-280℃, the main extruder speed is 200-350 rpm / min, and the screw length-to-diameter ratio is 40:1. After injection molding, the product is tested according to standards. Product performance tests are shown in Table 1.

[0077] Example 12

[0078] Weigh out 53.5% nylon 66 resin, 4% PDPCP, 3% PBO chopped short fibers (6mm), 3% heterocyclic aramid chopped short fibers (6mm), 0.5% antioxidant 168, 0.5% silicone powder, and 0.5% nano-montmorillonite by weight percentage, disperse and mix them in a high-speed mixer, and then add them through the main feed port. Add 35% glass fiber through the side feed port. The mixture is then melted, mixed, extruded, cooled, dried, and pelletized using a twin-screw extruder. The extrusion temperature of the twin-screw extruder is 260-280℃, the main extruder speed is 200-350 rpm / min, and the screw length-to-diameter ratio is 40:1. After injection molding, the product is tested according to standards; product performance tests are shown in Table 1.

[0079] Example 13

[0080] Weigh out 53.5% nylon 66 resin, 4% PDPCP, 3% PBO chopped short fibers (6mm), 3% heterocyclic aramid chopped short fibers (6mm), 0.5% antioxidant 1098, 0.5% silicone powder, and 0.5% nano-montmorillonite by weight percentage, disperse and mix them in a high-speed mixer, and then add them through the main feed port. Add 35% glass fiber through the side feed port. The mixture is then melted, mixed, extruded, cooled, dried, and pelletized using a twin-screw extruder. The extrusion temperature of the twin-screw extruder is 260-280℃, the main extruder speed is 200-350 rpm / min, and the screw length-to-diameter ratio is 40:1. After injection molding, the product is tested according to standards; product performance tests are shown in Table 1.

[0081] Example 14

[0082] Weigh out 53.5% nylon 66 resin, 4% PDPCP, 3% PBO chopped short fibers (6mm), 3% heterocyclic aramid chopped short fibers (6mm), 0.5% antioxidant H161, 0.5% silicone powder, and 0.5% boron nitride by weight percentage, disperse and mix them in a high-speed mixer, and then add them through the main feed port. Add 35% glass fiber through the side feed port. The mixture is then melted, mixed, extruded, cooled, dried, and pelletized using a twin-screw extruder. The extrusion temperature of the twin-screw extruder is 260-280℃, the main extruder speed is 200-350 rpm / min, and the screw length-to-diameter ratio is 40:1. After injection molding, the product is tested according to standards; product performance tests are shown in Table 1.

[0083] Comparative Example 1

[0084] Weigh out 56.5% nylon 66 resin, 1% PDPCP, 3% PBO chopped fibers, 3% heterocyclic aramid chopped fibers, 0.5% antioxidant 1098, 0.5% silicone powder, and 0.5% fine talc powder by weight percentage, add them to a high-speed mixer for dispersion and mixing, and then add them through the main feed port. Add 35% glass fiber through the side feed port. The mixture is then melted, mixed, extruded, cooled, dried, and pelletized using a twin-screw extruder. The extrusion temperature of the twin-screw extruder is 260-280℃, the main extruder speed is 200-350 rpm / min, and the screw length-to-diameter ratio is 40:1. After injection molding, the product is tested according to standards; product performance tests are shown in Table 1.

[0085] Comparative Example 2

[0086] Weigh out 47.5% nylon 66 resin, 10% PDPCP, 3% PBO chopped fibers, 3% heterocyclic aramid chopped fibers, 0.5% antioxidant 1098, 0.5% silicone powder, and 0.5% fine talc powder by weight percentage, add them to a high-speed mixer for dispersion and mixing, and then add them through the main feed port. Add 35% glass fiber through the side feed port. The mixture is then melted, mixed, extruded, cooled, dried, and pelletized using a twin-screw extruder. The extrusion temperature of the twin-screw extruder is 260-280℃, the main extruder speed is 200-350 rpm / min, and the screw length-to-diameter ratio is 40:1. After injection molding, the product is tested according to standards; product performance tests are shown in Table 1.

[0087] Comparative Example 3

[0088] Weigh out 53.5% nylon 66 resin, 4% PDPCP, 0.5% antioxidant 1098, 0.5% silicone powder, and 0.5% fine talc powder according to the specified mass ratio. Add these components to a high-speed mixer for dispersion and mixing, then feed them through the main feed inlet. Add 41% glass fiber through the side feed inlet. The mixture is then melted, mixed, extruded, cooled, dried, and pelletized using a twin-screw extruder. The extrusion temperature of the twin-screw extruder is 260-280℃, the main extruder speed is 200-350 rpm / min, and the screw length-to-diameter ratio is 40:1. After injection molding, the product is tested according to standards. Product performance tests are shown in Table 1.

[0089] Comparative Example 4

[0090] Weigh out 53.5% nylon 66 resin, 0.5% antioxidant 1098, 0.5% silicone powder, and 0.5% fine talc powder according to the specified mass ratio, add them to a high-speed mixer for dispersion and mixing, and then add them through the main feed port. Add 45% glass fiber through the side feed port. The mixture is then melted, mixed, extruded, cooled, dried, and pelletized using a twin-screw extruder. The extrusion temperature of the twin-screw extruder is 260-280℃, the main extruder speed is 200-350 rpm / min, and the screw length-to-diameter ratio is 40:1. After injection molding, the product is tested according to standards; product performance tests are shown in Table 1.

[0091] Comparative Example 5

[0092] Weigh out 57.5% nylon 66 resin, 3% PBO chopped short fibers (6mm), 3% heterocyclic aramid chopped short fibers (6mm), 0.5% antioxidant 1098, 0.5% silicone powder, and 0.5% fine talc powder by weight percentage. Add these components to a high-speed mixer for dispersion and mixing, then feed them through the main feed inlet. Add 35% glass fiber through the side feed inlet. The mixture is then melted, mixed, extruded, cooled, dried, and pelletized using a twin-screw extruder. The extrusion temperature of the twin-screw extruder is 260-280℃, the main extruder speed is 200-350 rpm / min, and the screw length-to-diameter ratio is 40:1. After injection molding, the product is tested according to standards. Product performance test results are shown in Table 1.

[0093] Table 1. Performance test data of flame-retardant nylon composite materials in Examples 1-14 and Comparative Examples 1-5.

[0094]

[0095] All aspects, embodiments, and features of this invention should be considered illustrative in all respects and are not intended to limit the invention; the scope of the invention is defined only by the claims. Other embodiments, modifications, and uses will become apparent to those skilled in the art without departing from the spirit and scope of the invention as claimed.

[0096] In addition, the inventors of this case also conducted experiments with other raw materials, process operations, and process conditions described in this specification, referring to the aforementioned embodiments, and obtained relatively ideal results in all cases.

[0097] Although the invention has been described with reference to illustrative embodiments, those skilled in the art will understand that various other changes, omissions, and / or additions can be made without departing from the spirit and scope of the invention, and that elements of the described embodiments can be substituted with substantially equivalents. Furthermore, many modifications can be made without departing from the scope of the invention to adapt particular situations or materials to the teachings of the invention. Therefore, this invention is not intended to be limited to the specific embodiments disclosed for carrying out the invention, but rather is intended to encompass all embodiments falling within the scope of the appended claims.

Claims

1. A flame-retardant nylon composite material, characterized in that, The raw materials for preparing the flame-retardant nylon composite material include the following components by weight percentage: nylon resin 30%~70%, 1,4-bis(diphenoxyphosphoryl)piperazine 3%~6%, polyphenylene benzodioxazole chopped fibers 1%~5%, heterocyclic aramid chopped fibers 1%~5%, glass fiber 20~60%, antioxidant 0.1%~1%, lubricant 0.1%~1%, and nucleating agent 0.1%~1%. The polyphenylene benzodioxazole chopped fibers have a length of 3-7 mm and a single filament diameter of 5-15 μm; the heterocyclic aramid chopped fibers are aramid III fibers with a length of 3-7 mm and a single filament diameter of 5-15 μm.

2. The flame-retardant nylon composite material according to claim 1, characterized in that: The nylon resin includes any one or a combination of two or more of nylon 66 resin, nylon 6 resin, nylon 6T resin, and nylon 10T resin.

3. The flame-retardant nylon composite material according to claim 1, characterized in that: The antioxidants include any one or a combination of two or more of the following: antioxidant 1098, antioxidant H161, and antioxidant 168.

4. The flame-retardant nylon composite material according to claim 1, characterized in that: The lubricant includes silicone-based lubricants.

5. The flame-retardant nylon composite material according to claim 1, characterized in that: The nucleating agent includes any one or a combination of two or more of nano-montmorillonite, fine talc powder, and boron nitride.

6. The flame-retardant nylon composite material according to claim 1, characterized in that: The flame retardant properties of the flame-retardant nylon composite material are V0.

7. The flame-retardant nylon composite material according to claim 1, characterized in that: The tensile strength of the flame-retardant nylon composite material is 100~250 MPa.

8. The flame-retardant nylon composite material according to claim 1, characterized in that: The flexural strength of the flame-retardant nylon composite material is 150~300 MPa.

9. The flame-retardant nylon composite material according to claim 1, characterized in that: The flexural modulus of the flame-retardant nylon composite material is 8000~15000 MPa.

10. The flame-retardant nylon composite material according to claim 1, characterized in that: The unnotched impact strength of the simply supported beam of the flame-retardant nylon composite material is 30~100kJ / m. 2 .

11. The flame-retardant nylon composite material according to claim 1, characterized in that: The notched impact strength of the simply supported beam of the flame-retardant nylon composite material is 3~10 kJ / m. 2 .

12. The method for preparing the flame-retardant nylon composite material according to any one of claims 1-11, characterized in that, include: The flame-retardant nylon composite material is prepared by compounding a mixture of nylon resin, 1,4-bis(diphenoxyphosphoryl)piperazine, polyphenylene benzodioxazole chopped fibers, heterocyclic aramid chopped fibers, antioxidant, lubricant, and nucleating agent with glass fiber.

13. The preparation method according to claim 12, characterized in that, include: A mixture containing nylon resin, 1,4-bis(diphenoxyphosphoryl)piperazine, polyphenylene benzodioxazole chopped fibers, heterocyclic aramid chopped fibers, antioxidant, lubricant, and nucleating agent is vacuum dried at 100~120ºC for 6-12h to obtain a mixture.

14. The preparation method according to claim 13, characterized in that, Also includes: The mixture is compounded with glass fiber using a twin-screw extrusion process to prepare the flame-retardant nylon composite material.

15. The application of the flame-retardant nylon composite material according to any one of claims 1-11 in the fields of automotive, electronic and electrical, aerospace or defense technology.

16. The application according to claim 15, characterized in that: Applications of the flame-retardant nylon composite material in the automotive or electronic and electrical fields.

Images