Nylon composite material and preparation method thereof

Abstract

The invention discloses a nylon composite material and a preparation method thereof. The nylon composite material is prepared from polyamide, GF-POSS-1, GF-POSS-2, a toughening agent, an antioxidant and a lubricating agent. The GF-POSS-1 is obtained by reacting an aminated solid glass fiber and epoxidized POSS in a weight ratio of 5: (0.5-2); the GF-POSS-2 is obtained by reacting epoxidized hollow glass fibers and aminated POSS according to a weight ratio of 5: (0.5 to 2). The nylon composite material disclosed by the invention has excellent comprehensive properties of high tensile strength, high toughness, low dielectric constant and low dielectric loss, and is suitable for high-end scenes such as 5G communication and high-frequency electronic packaging.

Description

Technical Field

[0001] The present invention belongs to the field of composite materials, and in particular relates to a high-strength and low-dielectric nylon composite material and a preparation method thereof. Background Art

[0002] As 5G communications extend into millimeter-wave frequency bands, high-frequency signal transmission places stringent demands on the dielectric properties of electronic components. Traditional epoxy resin substrates are no longer able to meet the requirements of high-frequency PCBs, antenna packaging, and other applications. The development of polymer materials with low dielectric constants and low losses has become a core issue in the industry.

[0003] Polyamide is widely used in electronic devices such as connectors and chip packaging due to its high strength, heat resistance, and chemical corrosion resistance. However, the high polarity of the amide bond in the polyamide molecular chain causes its dielectric properties to deteriorate severely, which leads to loss and delay of electromagnetic signals during transmission, affecting device performance. Introducing a foamed porous structure or adding a low-dielectric inorganic filler such as glass fiber to polyamide is the most common method for reducing the dielectric constant of polymers. It is worth noting that the foamed porous structure often causes a significant decrease in the mechanical properties of polyamide. Although the reinforcing effect of the low-dielectric filler in polyamide composites shows obvious advantages over the foamed porous structure, it is not ideal for reducing the dielectric constant of polymers. Only by adding a sufficient amount of low-dielectric filler can a good low-dielectric effect be achieved. However, the addition of a large amount of low-dielectric filler also affects the mechanical properties of the material. For example, Chinese invention patent CN108410167A incorporates glass fiber and a nucleating agent into polyamide and produces a low-dielectric nylon composite material by melt extrusion. Although the tensile strength of the material is high, its dielectric constant is still higher than 3.5. Chinese invention patent CN114644828B introduces hollow glass fibers into polyamide, utilizing the hollow structure to further reduce the dielectric constant of polyamide. However, the introduction of a large number of hollow structures is not conducive to the mechanical properties of the material.

[0004] As can be seen, although the filling of filler can reduce the overall polarity of the material, reduce dielectric constant and loss, it is necessary to have enough consumption, but the incorporation of excessive filler can cause the interface defect between it and the polyamide matrix to increase, significantly reducing processing and forming performance and mechanical properties etc. In addition, the compatibility of polymer and filler is poor, and high-content filler is more difficult to be evenly dispersed in polymer, causing polymer-based composite material dielectric properties and mechanical properties to significantly deteriorate. Meanwhile, polyamide is due to the interpolation of a large amount of rigid low-dielectric fillers, and its toughness also can significantly decline, which all seriously limits its application in the field of electronics. Therefore, how to develop a polyamide composite material with low dielectric constant and low dielectric loss while having high tensile strength, high toughness is a difficult problem in this area always. Summary of the Invention

[0005] Based on this, the object of the present invention is to provide a nylon composite material with high tensile strength, high toughness, low dielectric constant and low dielectric loss.

[0006] The specific technical solutions for achieving the above-mentioned invention objectives include the following.

[0007] In a first aspect of the present invention, a nylon composite material is provided, which is prepared from the following raw materials in parts by weight:

[0008]

[0009] The GF-POSS-1 is obtained by reacting aminated solid glass fiber and epoxidized POSS in a weight ratio of 5:0.5-2; and the GF-POSS-2 is obtained by reacting epoxidized hollow glass fiber and aminated POSS in a weight ratio of 5:0.5-2.

[0010] The second aspect of the present invention provides a method for preparing the above-mentioned nylon composite material, comprising the following steps: mixing the polyurethane, toughening agent, antioxidant and lubricant, and adding the mixture from the main feed port of a twin-screw extruder; mixing the GF-POSS-1 and GF-POSS-2, and adding the mixture from the side feed port of the twin-screw extruder; and melt blending, extruding and granulating to obtain the product.

[0011] The nylon composite material is prepared by using polyamide, GF-POSS-1 prepared by grafting epoxidized POSS on the surface of aminated solid glass fiber, GF-POSS-2 prepared by grafting aminated POSS on the surface of epoxidized hollow glass fiber, and a maleic anhydride grafted toughener as main raw materials. On the one hand, GF-POSS-1 and GF-POSS-2 react to strengthen the bonding force between the glass fibers; on the other hand, amino groups and epoxy groups on the surfaces of GF-POSS-1 and GF-POSS-2 undergo condensation or ring-opening reaction with terminal carboxyl groups or terminal amino groups of nylon, thereby enhancing the compatibility between the glass fiber and the nylon matrix, suppressing interface debonding, and improving the overall strength; and On the one hand, the amino and epoxy groups on the surface of GF-POSS-1 and GF-POSS-2 react with the toughening agent grafted with maleic anhydride to form an interpenetrating network of "filler-toughening agent-nylon". At the same time, the dispersed phase of the toughening agent absorbs the impact energy to achieve a balance between strength and toughness. Therefore, the dielectric is regulated by the design of the composite structure of GF-POSS-1 and GF-POSS-2, chemical cross-linking improves the compatibility between fillers, toughening agents and polymers, and the interface modification and toughening multi-scale collaborative design improve tensile strength and toughness. The nylon composite material of the present invention has excellent comprehensive performance of high tensile strength, high toughness, low dielectric constant and low dielectric loss, and is suitable for high-end scenarios such as 5G communications and high-frequency electronic packaging. DETAILED DESCRIPTION

[0012] To facilitate understanding of the present invention, the present invention will be described more fully below. The present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the present disclosure more thorough and comprehensive.

[0013] Unless otherwise defined, all technical and scientific terms used herein have the same meanings as commonly understood by those skilled in the art to which this invention pertains. The terms used in this specification are for the purpose of describing specific embodiments only and are not intended to limit the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0014] In some embodiments of the present invention, a nylon composite material is disclosed, which is prepared from the following raw materials in parts by weight:

[0015]

[0016] The GF-POSS-1 is obtained by reacting aminated solid glass fiber and epoxidized POSS in a weight ratio of 5:0.5-2; and the GF-POSS-2 is obtained by reacting epoxidized hollow glass fiber and aminated POSS in a weight ratio of 5:0.5-2.

[0017] The working principles of the various raw materials of the nylon composite material of the present invention are as follows:

[0018] 1. The compounding of solid glass fiber and hollow glass fiber makes the nylon composite material have both the high mechanical strength of solid fiber and the low dielectric properties of hollow fiber.

[0019] 2. Use epoxidized / amino-modified polyhedral oligomeric silsesquioxane POSS with organic-inorganic properties to modify the glass fiber and optimize the dielectric and hydrophobic properties of the composite material. POSS has a low-polarity siloxane skeleton (Si-O-Si), and there are nanoscale pores (0.3-0.5nm) inside its cage structure, which can reduce the polarization response and effectively reduce the dielectric constant and dielectric loss of the composite material, so that the nylon composite material has a lower dielectric constant and dielectric loss in the 5G frequency band. In addition, the cage structure, as a nano-reinforcement phase, can improve the rigid modulus of the composite material through chemical cross-linking. At the same time, the rigid core of POSS strengthens the stress transfer efficiency between the glass fiber and the nylon matrix through the "pinning effect", thereby improving the mechanical properties of the composite material.

[0020] 3. A composite of epoxy- and amino-functionalized glass fibers grafted with amino- and epoxy-functionalized POSS is used as a low-dielectric filler. The organic-inorganic hybrid properties of POSS enable it to form covalent bonds with the glass fibers and react with the nylon matrix, constructing a tertiary interface structure of "glass fiber-POSS-matrix," effectively enhancing the tensile strength of the composite material. The resulting multiple cross-linked structure can significantly reduce the water absorption of the polyamide, allowing the composite material to maintain stable dielectric properties. In addition, the epoxy-amino covalent bond between GF-POSS-1 and GF-POSS-2 can strengthen the cross-linking of the fiber network and improve the hydrophilicity of traditional glass fibers. Its condensation and ring-opening reaction with the nylon matrix can enhance the compatibility of the system, effectively inhibiting interfacial debonding between the matrix and the filler, and further optimizing its dielectric properties.

[0021] 4. A maleic anhydride-grafted toughening agent is introduced. The anhydride group of the toughening agent reacts with the amino / epoxy groups on the surface of GF-POSS-1 and GF-POSS-2 to form a chemical bond. At the same time, its long-chain structure forms a "flexible buffer layer" with the nylon matrix through chain segment entanglement, which relieves interfacial stress. The toughening agent acts as an intermediate to connect the low-dielectric filler and the resin, effectively improving the compatibility of the composite material and playing an important role in enhancing the impact strength.

[0022] In some embodiments, the GF-POSS-1 is prepared by the following method: dispersing 5 parts of amino-treated solid glass fiber in 100 to 500 parts of solvent, adding 0.5 to 2 parts of epoxidized POSS, ultrasonicating for 1 to 3 hours, adding 0.05 to 0.2 parts of catalyst, stirring at 50° C. to 80° C. under a nitrogen atmosphere for 4 to 10 hours, and separating the product.

[0023] In some embodiments, the weight ratio of the amino-treated solid glass fiber to the epoxidized POSS is preferably 5:1.0-1.5.

[0024] In some embodiments, the GF-POSS-2 is prepared by the following method: dispersing 5 parts of epoxidized hollow glass fibers in 100 to 500 parts of a solvent, adding 0.5 to 2 parts of amino POSS, ultrasonicating for 1 hour to 3 hours, adding 0.05 to 0.2 parts of a catalyst, stirring at 50°C to 80°C under a nitrogen atmosphere for 4 hours to 10 hours, and separating the product.

[0025] In some embodiments, the weight ratio of the epoxidized hollow glass fiber to the amino-treated POSS is preferably 5:1.0-1.5.

[0026] In some embodiments, the toughening agent is a maleic anhydride grafted toughening agent.

[0027] In some embodiments, the toughening agent is one or more of maleic anhydride grafted POE, maleic anhydride grafted EPDM and maleic anhydride grafted SEBS, preferably maleic anhydride grafted POE or maleic anhydride grafted SEBS.

[0028] In some embodiments, the content of maleic anhydride in the toughening agent is 0.5-2%.

[0029] In some embodiments, the nylon composite material is prepared from the following raw materials in parts by weight:

[0030]

[0031] In some embodiments, the mass ratio of GF-POSS-1 to GF-POSS-2 is 0.5-1.

[0032] In some embodiments, the aminated solid glass fiber is obtained by reacting a silane coupling agent and solid glass fiber in a weight ratio of 0.5 to 1.5:5; the silane coupling agent is one or more of γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropyltriethoxysilane, N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane, N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane, γ-aminopropylmethyldimethoxysilane, and γ-aminopropylmethyldiethoxysilane.

[0033] In some embodiments, the silane coupling agent is γ-aminopropyltrimethoxysilane or γ-aminopropylmethyldiethoxysilane.

[0034] In some embodiments, the aminated solid glass fiber is prepared by the following method: adding 0.5 to 1.5 parts of a silane coupling agent to 100 to 500 parts of a mixed solution of ethanol and water in a mass ratio of 20 to 100:1, adjusting the pH of the solution to 3.5 to 5, then adding 5 parts of solid glass fiber, dispersing the mixture evenly, reflux reacting at 60°C to 100°C for 6h to 18h, and separating the product to obtain the product.

[0035] In some embodiments, the weight ratio of the silane coupling agent to the solid glass fiber is 0.5-1.0:5.

[0036] In some embodiments, the mass ratio of ethanol to water is 20-35:1.

[0037] In some embodiments, the solid glass fiber has a diameter of 8 μm to 20 μm and a length of 3 mm to 5 mm.

[0038] In some embodiments, the epoxidized hollow glass fiber is obtained by reacting a silane coupling agent and hollow glass fiber in a weight ratio of 0.5 to 1.5:5; the silane coupling agent is one or more of triethoxy(3-epoxypropyloxypropyl)silane, 3-glycidyloxypropyltrimethoxysilane, diethoxy(3-glycidyloxypropyl)methylsilane, [8-(epoxypropyloxy)-n-octyl]trimethoxysilane, and 3-[(2,3)-epoxypropyloxy]propylmethyldimethoxysilane.

[0039] In some embodiments, the silane coupling agent is 3-glycidyloxypropyltrimethoxysilane or diethoxy(3-glycidyloxypropyl)methylsilane.

[0040] In some embodiments, the epoxidized hollow glass fiber is prepared by the following method: adding 0.5 to 1.5 parts of a silane coupling agent to a mixed solution of 100 to 500 parts of ethanol and water in a mass ratio of 20 to 100:1, adjusting the pH of the solution to 3.5 to 5, then adding 5 parts of hollow glass fiber, dispersing them evenly, reflux reacting at 60° C. to 100° C. for 6 h to 18 h, and separating the product to obtain the product.

[0041] In some embodiments, the weight ratio of the silane coupling agent to the hollow glass fiber is 0.5-1.0:5.

[0042] In some embodiments, the mass ratio of ethanol to water is 20-35:1.

[0043] In some embodiments, the outer diameter of the hollow glass fiber is 10 μm to 20 μm, the ratio of the inner diameter to the outer diameter is 0.4 to 0.5, and the length is 0.5 mm to 2 mm.

[0044] In some embodiments, the functional substituents of the epoxidized POSS and the amino POSS are both 4 to 8.

[0045] In some embodiments, the solvent is ethanol or acetone; and the catalyst is triethylamine or triethylenediamine.

[0046] In some embodiments, the antioxidant is antioxidant 1010, antioxidant 1076, antioxidant 1098 or a phosphite antioxidant, preferably antioxidant 1010 or a phosphite antioxidant.

[0047] In some embodiments, the lubricant is one or more of silicone resin, polyethylene wax, stearamide, calcium stearate and pentaerythritol stearate, preferably silicone resin or polyethylene wax.

[0048] In some embodiments, the polyurethane is PA66 or PA6.

[0049] In other embodiments of the present invention, a method for preparing the above-mentioned nylon composite material is disclosed, comprising the following steps: mixing the polyurethane, toughening agent, antioxidant and lubricant, and adding the mixture from the main feed port of a twin-screw extruder; mixing the GF-POSS-1 and GF-POSS-2, and adding the mixture from the side feed port of the twin-screw extruder; and melt blending, extruding and granulating to obtain the product.

[0050] In some embodiments, the rotation speed of the twin-screw extruder is 200 rpm to 500 rpm, and the extrusion temperature is 230° C. to 280° C.

[0051] The PA66 used in the present invention was purchased from Dongguan Hengxin Engineering Plastics Co., Ltd. Solid glass fiber was purchased from Shandong Tonghui Glass Fiber Co., Ltd., with a diameter of 13 μm and a length of 3-4.5 mm. Hollow glass fiber was purchased from Taishan Glass Fiber Co., Ltd., with an outer diameter of 15 μm, an inner and outer diameter ratio of 0.4, and a length of 2 mm. Epoxidized POSS and amino-modified POSS (polyhedral oligomeric silsesquioxane) were purchased from Weibai'ao Biotechnology Co., Ltd., and the functional substituents were both 4 to 8. Maleic anhydride grafted POE (polyolefin elastomer) and maleic anhydride grafted SEBS (styrene-ethylene-butylene-styrene copolymer) were purchased from Dongguan Hengtai Plastic Co., Ltd., with a grafting rate of 1 to 1.5%. Antioxidant 1010 was purchased from Dongguan Zhenming Chemical Co., Ltd. Phosphite antioxidant (MIANOX9228) was purchased from Dongguan Baoxu Chemical Technology Co., Ltd. Silicone resin was purchased from Dongguan Zhonghui Plastic Additive Co., Ltd. Polyethylene wax was purchased from Guangzhou Yuantai New Materials Co., Ltd.

[0052] The present invention is described in detail below with reference to specific embodiments.

[0053] Example 1 High-strength low-dielectric nylon composite material and preparation method thereof

[0054] The high-strength, low-dielectric nylon composite material of this embodiment is prepared by the following steps:

[0055] 1. Preparation of amino-treated solid glass fiber

[0056] 1 g of γ-aminopropyltrimethoxysilane was added to a mixed solution of 480 g of ethanol and 20 g of water, and acid was added to adjust the solution pH to 4; subsequently, 5 g of solid glass fiber was added, ultrasonically dispersed evenly, and then refluxed at 80°C for 10 hours. The product was centrifuged and repeatedly washed with ethanol. After vacuum drying, amino-treated solid glass fiber was obtained.

[0057] 2. Preparation of solid glass fiber grafted epoxy functionalized POSS composite (GF-POSS-1)

[0058] 5g of aminated solid glass fiber was ultrasonically dispersed in 500g of ethanol. One part of epoxidized POSS was then added and sonicated for 2 hours to achieve uniform dispersion. Subsequently, 0.1 part of triethylamine (catalyst) was added to the solution, and the mixture was stirred at 60°C under a nitrogen atmosphere for 8 hours. Finally, the product was centrifuged, repeatedly washed with ethanol, and vacuum-dried to obtain GF-POSS-1.

[0059] 3. Preparation of epoxidized hollow glass fiber

[0060] 1 g of 3-glycidyloxypropyltrimethoxysilane was added to a mixed solution of 480 g of ethanol and 20 g of water, and acid was added to adjust the solution pH to 4. Subsequently, 5 g of hollow glass fiber was added, ultrasonically dispersed uniformly, and refluxed at 80°C for 10 hours. The product was centrifuged and repeatedly washed with ethanol. After vacuum drying, amino-modified solid glass fiber was obtained.

[0061] 4. Preparation of hollow glass fiber grafted epoxy functionalized POSS composite (GF-POSS-2)

[0062] 5g of epoxidized hollow glass fiber was ultrasonically dispersed in 500g of ethanol. One part of amino-treated POSS was then added and sonicated for 2 hours to achieve uniform dispersion. Subsequently, 0.1 part of triethylamine (catalyst) was added to the solution, and the mixture was stirred at 60°C under a nitrogen atmosphere for 8 hours. Finally, the product was centrifuged, repeatedly washed with ethanol, and vacuum-dried to obtain GF-POSS-2.

[0063] 5. Preparation of high-strength and low-dielectric nylon composite materials

[0064] The PA66 was placed in a 100°C oven to dry to remove absorbed moisture. Subsequently, 100 parts of PA66, 4 parts of maleic anhydride-grafted POE, 0.8 parts of antioxidant 1010, and 0.5 parts of silicone resin were mixed and added to the screw extruder from the main feed port. 25 parts of GF-POSS-1 and 25 parts of GF-POSS-2 were mixed and added from the side feed port. The mixture was melt-extruded and granulated to produce a high-strength, low-dielectric nylon composite material. The speed of the twin-screw extruder was 280 rpm, and the head temperatures of the twin-screw zones (zones 1 to 9) were set at 120°C, 240°C, 260°C, 270°C, 280°C, 270°C, 260°C, 250°C, and 240°C, respectively.

[0065] Example 2 High-strength low-dielectric nylon composite material and its preparation method

[0066] The high-strength, low-dielectric nylon composite material of this embodiment is prepared by the following steps:

[0067] Steps (1) to (4) are the same as in Example 1.

[0068] 5. Preparation of high-strength and low-dielectric nylon composite materials

[0069] PA66 was dried in a 100°C oven to remove absorbed moisture. Subsequently, 100 parts by mass of PA66, 3 parts of maleic anhydride-grafted POE, 0.8 parts of antioxidant 1010, and 0.5 parts of silicone resin were mixed and added to a screw extruder through the main feed port. 15 parts of GF-POSS-1 and 30 parts of GF-POSS-2 were mixed and added through the side feed port. The mixture was melt-extruded and granulated to produce a high-strength, low-dielectric nylon composite material. The speed and temperature of the twin-screw extruder were the same as in Example 1.

[0070] Example 3 High-strength low-dielectric nylon composite material and its preparation method

[0071] The high-strength, low-dielectric nylon composite material of this embodiment is prepared by the following steps:

[0072] 1. Preparation of amino-treated solid glass fiber

[0073] 0.5 g of γ-aminopropylmethyldiethoxysilane was added to a mixed solution of 97 g of ethanol and 3 g of water, and acid was added to adjust the pH of the solution to 5; subsequently, 5 g of solid glass fiber was added, ultrasonically dispersed evenly, and then refluxed at 60°C for 18 hours. The product was centrifuged and repeatedly washed with ethanol. After vacuum drying, amino-treated solid glass fiber was obtained.

[0074] 2. Preparation of solid glass fiber grafted epoxy functionalized POSS composite (GF-POSS-1)

[0075] 5g of aminated solid glass fiber was ultrasonically dispersed in 300g of acetone, followed by the addition of 1.5 parts of epoxidized POSS, and the mixture was sonicated for 3 hours to achieve uniform dispersion. Subsequently, 0.2 parts of triethylenediamine (catalyst) was added to the solution, and the mixture was stirred at 80°C for 4 hours under a nitrogen atmosphere. Finally, the product was centrifuged, repeatedly washed with ethanol, and vacuum-dried to obtain GF-POSS-1.

[0076] 3. Preparation of epoxidized hollow glass fiber

[0077] 0.5 g of diethoxy(3-glycidyloxypropyl)methylsilane was added to a mixed solution of 97 g of ethanol and 3 g of water, and acid was added to adjust the pH of the solution to 5; then, 5 g of hollow glass fiber was added, ultrasonically dispersed evenly, and refluxed at 60°C for 18 hours. The product was centrifuged and repeatedly washed with ethanol. After vacuum drying, epoxidized solid glass fiber was obtained.

[0078] 4. Preparation of hollow glass fiber grafted epoxy functionalized POSS composite (GF-POSS-2)

[0079] 5g of epoxidized hollow glass fiber was ultrasonically dispersed in 300g of acetone, followed by the addition of 1.5 parts of amino-POSS and sonication for 3 hours to achieve uniform dispersion. Subsequently, 0.2 parts of triethylenediamine (catalyst) was added to the solution, and the mixture was stirred at 80°C under a nitrogen atmosphere for 4 hours. Finally, the product was centrifuged, repeatedly washed with ethanol, and vacuum-dried to obtain GF-POSS-1.

[0080] 5. Preparation of high-strength and low-dielectric nylon composite materials

[0081] PA66 was dried in a 100°C oven to remove absorbed moisture. Subsequently, 100 parts by mass of PA66, 6 parts of maleic anhydride-grafted SEBS, 0.8 parts of a phosphite antioxidant, and 0.5 parts of polyethylene wax were mixed and fed into a screw extruder through the main feed port. 30 parts of GF-POSS-1 and 30 parts of GF-POSS-2 were mixed and fed through a side feed port. The mixture was melt-extruded and granulated to produce a high-strength, low-dielectric nylon composite material. The speed and temperature of the twin-screw extruder were the same as in Example 1.

[0082] Example 4 High-strength low-dielectric nylon composite material and its preparation method

[0083] The high-strength, low-dielectric nylon composite material of this embodiment is prepared by the following steps:

[0084] Steps (1) to (4) are the same as in Example 3.

[0085] 5. Preparation of high-strength and low-dielectric nylon composite materials

[0086] PA66 was dried in a 100°C oven to remove absorbed moisture. Subsequently, 100 parts by mass of PA66, 2 parts of maleic anhydride-grafted SEBS, 0.8 parts of a phosphite antioxidant, and 0.5 parts of polyethylene wax were mixed and fed into a screw extruder through the main feed port. 20 parts of GF-POSS-1 and 15 parts of GF-POSS-2 were mixed and fed through a side feed port. The mixture was melt-extruded and granulated to produce a high-strength, low-dielectric nylon composite material. The speed and temperature of the twin-screw extruder were the same as in Example 1.

[0087] Comparative Example 1

[0088] The nylon composite material of this comparative example was prepared by the following steps:

[0089] Steps (1) to (2) are the same as in Example 1.

[0090] 3. Preparation of nylon composite materials

[0091] PA66 was dried in a 100°C oven to remove absorbed moisture. Subsequently, 100 parts by mass of PA66, 4 parts of maleic anhydride-grafted POE, 0.8 parts of antioxidant 1010, and 0.5 parts of silicone resin were mixed and fed into a screw extruder through the main feed port. 50 parts of GF-POSS-1 was added through the side feed port, and melt extrusion and pelletization were performed to produce a nylon composite material. The speed and temperature of the twin-screw extruder were the same as in Example 1.

[0092] Comparative Example 2

[0093] The nylon composite material of this comparative example was prepared by the following steps:

[0094] 1. Preparation of epoxidized hollow glass fiber

[0095] Same as Example 1.

[0096] 2. Preparation of hollow glass fiber grafted epoxy functionalized POSS composite (GF-POSS-2)

[0097] Same as Example 1.

[0098] 3. Preparation of nylon composite materials

[0099] PA66 was dried in a 100°C oven to remove absorbed moisture. Subsequently, 100 parts by mass of PA66, 4 parts of maleic anhydride-grafted POE, 0.8 parts of antioxidant 1010, and 0.5 parts of silicone resin were mixed and fed into a screw extruder through the main feed port. 50 parts of GF-POSS-2 were added through the side feed port, and melt-extruded and granulated to produce a nylon composite material. The speed and temperature of the twin-screw extruder were the same as in Example 1.

[0100] Comparative Example 3

[0101] The nylon composite material of this comparative example was prepared by the following steps:

[0102] 1. Preparation of amino-treated solid glass fiber

[0103] Same as Example 1.

[0104] 2. Preparation of epoxidized hollow glass fiber

[0105] Same as Example 1.

[0106] 3. Preparation of nylon composite materials

[0107] PA66 was dried in a 100°C oven to remove absorbed moisture. Subsequently, 100 parts by mass of PA66, 4 parts of maleic anhydride-grafted POE, 0.8 parts of antioxidant 1010, and 0.5 parts of silicone resin were mixed and fed into a screw extruder through the main feed port. 25 parts of amino-treated solid glass fiber and 25 parts of epoxidized hollow glass fiber were added through the side feed port, and melt-extruded and pelletized to produce a nylon composite material. The speed and temperature of the twin-screw extruder were the same as in Example 1.

[0108] Comparative Example 4

[0109] The nylon composite material of this comparative example was prepared by the following steps:

[0110] 1. Preparation of amino-treated solid glass fiber

[0111] Same as Example 1.

[0112] 2. Preparation of epoxidized hollow glass fiber

[0113] Same as Example 1.

[0114] 3. Preparation of nylon composite materials

[0115] PA66 was placed in a 100°C oven to dry to remove absorbed moisture. Subsequently, 100 parts of PA66, 4 parts of maleic anhydride-grafted POE, 5 parts of epoxidized POSS, 5 parts of amino-containing POSS, 0.8 parts of antioxidant 1010, and 0.5 parts of silicone resin were mixed, by weight, and fed into a screw extruder through the main feed port. 25 parts of amino-containing solid glass fibers and 25 parts of epoxidized hollow glass fibers were added through the side feed port, and melt-extruded and granulated to produce a nylon composite material. The speed and temperature of the twin-screw extruder were the same as in Example 1.

[0116] Comparative Example 5

[0117] The nylon composite material of this comparative example was prepared by the following steps:

[0118] Steps (1) to (4) are the same as in Example 1.

[0119] 5. Preparation of high-strength and low-dielectric nylon composite materials

[0120] PA66 was dried in an oven at 100°C to remove absorbed moisture. Subsequently, 100 parts by mass of PA66, 0.8 parts of antioxidant 1010, and 0.5 parts of silicone resin were mixed and fed into a screw extruder through the main feed port. 25 parts of GF-POSS-1 and 25 parts of GF-POSS-2 were added through the side feed port, and melt extrusion and granulation were performed to produce a nylon composite material. The speed and temperature of the twin-screw extruder were the same as in Example 1.

[0121] Comparative Example 6

[0122] The nylon composite material of this comparative example was prepared by the following steps:

[0123] Steps (1) to (4) are the same as in Example 1.

[0124] 5. Preparation of high-strength and low-dielectric nylon composite materials

[0125] PA66 was dried in a 100°C oven to remove absorbed moisture. Subsequently, 100 parts by mass of PA66, 4 parts of ethylene propylene diene monomer (EPDM), 0.8 parts of antioxidant 1010, and 0.5 parts of silicone resin were mixed and fed into a screw extruder through the main feed port. 25 parts of GF-POSS-1 and 25 parts of GF-POSS-2 were added through the side feed port, and melt extrusion and granulation were performed to produce a nylon composite material. The speed and temperature of the twin-screw extruder were the same as in Example 1.

[0126] The following performance tests were performed on the nylon composite materials prepared in the above embodiments and comparative examples:

[0127] Tensile strength: tested according to GB / T 1040-2006 standard, tensile rate 10mm / min;

[0128] Impact strength: tested according to GB / T 1843-2008 standard, V-notch, notch depth 2mm.

[0129] Dielectric constant: tested according to GB / T 1236 standard.

[0130] Dielectric loss factor: tested according to GB / T 1236 standard.

[0131] The performance test results are shown in Table 1.

[0132] Table 1

[0133]

[0134]

[0135] As can be seen from Table 1, embodiment 1~4 is by using PA66, GF-POSS-1, GF-POSS-2 and maleic anhydride grafted toughening agent as raw material, between each component, build interpenetrating network with chemical bond connection, GF-POSS filler plays the effect of improving tensile strength and reducing dielectric property, the toughening agent of maleic anhydride grafting can improve impact strength, therefore, the nylon composite material obtained has high tensile strength, high impact strength, low dielectric constant and low dielectric loss factor.Along with the increase of GF-POSS filler addition, the dielectric constant of nylon composite material reduces.In addition, the mechanical property of nylon composite material is closely related to GF-POSS filler and toughening agent content, and material overall keeps good tensile strength and impact property.

[0136] Compared with Example 1, in Comparative Example 1, only GF-POSS-1 was added as filler, and the tensile strength of the prepared nylon composite material was 148 MPa and the impact strength was 11.8 kJ / m 2 , dielectric constant is 3.78, and dielectric loss factor is 0.030, and the mechanical property and the dielectric property of composite material are all significantly deteriorated.Compared with hollow glass fiber (comparative example 2), the solid structure of GF-POSS-1 significantly improves dielectric constant and dielectric loss.In addition, there are too many epoxy groups in system, and each component of system is difficult to form stable chemical bond, so the active force between filler and filler and between filler and nylon molecular chain significantly declines, and this has caused greater damage to mechanical property.

[0137] Compared with Example 1, in Comparative Example 2, only GF-POSS-2 was added as filler, and the tensile strength of the prepared nylon composite material was 115 MPa and the impact strength was 10.2 kJ / m 2 , the dielectric constant is 2.98, and the dielectric loss coefficient is 0.008. It can be seen that although only adding modified hollow glass fiber can effectively reduce the dielectric constant and dielectric loss, it has an extremely adverse effect on the mechanical properties.

[0138] Compared with Example 1, in Comparative Example 3, amino-functionalized solid glass fibers and epoxy-functionalized hollow glass fibers were added as fillers. The tensile strength of the prepared nylon composite material was 143 MPa and the impact strength was 13.6 kJ / m 2 , the dielectric constant is 3.45, and the dielectric loss factor is 0.023. Although chemical bonding can occur between amino glass fiber and epoxidized glass fiber, the mechanical strength of the nylon composite material is reduced and the dielectric properties are poor due to the lack of POSS.

[0139] Compared with Example 1, in Comparative Example 4, PA66, amination solid glass fiber, epoxidized hollow glass fiber, amination POSS, epoxidized POSS and toughening agent were directly compounded and melt-granulated. The tensile strength of the prepared nylon composite material was 135 MPa and the impact strength was 12.0 kJ / m 2 , the dielectric constant is 3.22, and the dielectric loss factor is 0.014. Although PA66, epoxidized POSS, amino-treated glass fiber and toughening agent can form a multi-crosslinked structure, the incorporation of multiple fillers makes dispersion difficult, and the mechanical and dielectric properties of the composite material deteriorate.

[0140] Compared with Example 1, in Comparative Example 5, no toughening agent was added, and the tensile strength of the prepared nylon composite material was 162 MPa and the impact strength was 8.3 kJ / m 2 , a dielectric constant of 3.15, and a dielectric loss factor of 0.013. POE-g-MAH acts as a compatibilizer and toughening agent in the system, significantly improving the adhesion between the glass fiber and the matrix, absorbing impact energy, and preventing crack propagation. Therefore, the absence of POE-g-MAH leads to a significant deterioration in the mechanical properties of the composite material.

[0141] Compared with Example 1, in Comparative Example 6, EPDM was added as a toughening agent, and the tensile strength of the prepared nylon composite material was 157 MPa and the impact strength was 10.2 kJ / m 2 , a dielectric constant of 3.20, and a dielectric loss factor of 0.016. EPDM is a non-polar rubber with no reactive maleic anhydride groups on its surface. Therefore, it has poor compatibility with PA66 and weak interfacial bonding, resulting in significantly poor mechanical and dielectric properties.

[0142] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0143] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A nylon composite material, characterized in that: It is prepared from the following raw materials in parts by weight: The GF-POSS-1 is obtained by reacting aminated solid glass fiber and epoxidized POSS in a weight ratio of 5:0.5-2; and the GF-POSS-2 is obtained by reacting epoxidized hollow glass fiber and aminated POSS in a weight ratio of 5:0.5-2.

2. The nylon composite material according to claim 1, characterized in that The GF-POSS-1 is prepared by the following method: dispersing 5 parts of aminated solid glass fiber in 100 parts to 500 parts of solvent, adding 0.5 parts to 2 parts of epoxidized POSS, ultrasonicating for 1 to 3 hours, adding 0.05 parts to 0.2 parts of catalyst, stirring at 50° C. to 80° C. for 4 hours to 10 hours under a nitrogen atmosphere, and separating the product; preferably, the weight ratio of the aminated solid glass fiber to the epoxidized POSS is 5: 1.0～1.5； And / or, the GF-POSS-2 is prepared by the following method: dispersing 5 parts of epoxidized hollow glass fibers in 100 parts to 500 parts of a solvent, adding 0.5 parts to 2 parts of amino POSS, ultrasonicating for 1 hour to 3 hours, adding 0.05 parts to 0.2 parts of a catalyst, stirring at 50° C. to 80° C. for 4 hours to 10 hours under a nitrogen atmosphere, and separating the product; preferably, the weight ratio of the epoxidized hollow glass fibers to the amino POSS is 5: 1.0～1.5； And / or, the toughening agent is a maleic anhydride grafted toughening agent, preferably, the toughening agent is one or more of maleic anhydride grafted POE, maleic anhydride grafted EPDM and maleic anhydride grafted SEBS, more preferably maleic anhydride grafted POE or maleic anhydride grafted SEBS; preferably, the content of maleic anhydride in the toughening agent is 0.5-2%.

3. The nylon composite material according to claim 1, characterized in that It is prepared from the following raw materials in parts by weight:

4. The nylon composite material according to claim 1, characterized in that The mass ratio of the GF-POSS-1 to the GF-POSS-2 is 0.5 to 1.5, preferably 0.5 to 1.

0.

5. The nylon composite material according to claim 1, characterized in that The amination-modified solid glass fiber is obtained by reacting a silane coupling agent and solid glass fiber in a weight ratio of 0.5 to 1.5:5; the silane coupling agent is one or more of γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropyltriethoxysilane, N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane, N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane, γ-aminopropylmethyldimethoxysilane, and γ-aminopropylmethyldiethoxysilane; the silane coupling agent is preferably γ-aminopropyltrimethoxysilane or γ-aminopropylmethyldiethoxysilane; And / or, the epoxidized hollow glass fiber is obtained by reacting a silane coupling agent and hollow glass fiber in a weight ratio of 0.5 to 1.5:5; the silane coupling agent is one or more of triethoxy(3-epoxypropyloxypropyl)silane, 3-glycidyloxypropyltrimethoxysilane, diethoxy(3-glycidyloxypropyl)methylsilane, [8-(epoxypropyloxy)-n-octyl]trimethoxysilane, and 3-[(2,3)-epoxypropyloxy]propylmethyldimethoxysilane; the silane coupling agent is preferably 3-glycidyloxypropyltrimethoxysilane or diethoxy(3-glycidyloxypropyl)methylsilane.

6. The nylon composite material according to claim 5, characterized in that: The amination-modified solid glass fiber is prepared by the following method: adding 0.5 to 1.5 parts of a silane coupling agent to 100 to 500 parts of a mixed solution of ethanol and water in a mass ratio of 20 to 100:1, then adjusting the pH of the solution to 3.5 to 5, adding 5 parts of solid glass fiber, uniformly dispersing the mixture, reflux reaction at 60° C. to 100° C. for 6 hours to 18 hours, and separating the product to obtain the amination-modified solid glass fiber; preferably, the weight ratio of the silane coupling agent to the solid glass fiber is 0.5 to 1.0:5; and the mass ratio of the ethanol to water is 20 to 35:1; And / or, the epoxidized hollow glass fiber is prepared by the following method: adding 0.5 to 1.5 parts of a silane coupling agent to 100 to 500 parts of a mixed solution of ethanol and water in a mass ratio of 20 to 100:1, then adjusting the pH of the solution to 3.5 to 5, adding 5 parts of hollow glass fiber, uniformly dispersing, reflux reaction at 60° C. to 100° C. for 6 h to 18 h, and separating the product; preferably, the weight ratio of the silane coupling agent to the hollow glass fiber is 0.5 to 1.0:5; the mass ratio of the ethanol to water is 20 to 35:1; and / or, the solid glass fiber has a diameter of 8 μm to 20 μm and a length of 3 mm to 5 mm; And / or, the outer diameter of the hollow glass fiber is 10 μm to 20 μm, the ratio of the inner and outer diameters is 0.4 to 0.5, and the length is 0.5 mm to 2 mm.

7. The nylon composite material according to claim 1, characterized in that The functional substituents of the epoxidized POSS and the amino POSS are both 4 to 8; and / or, the solvent is ethanol or acetone; And / or, the catalyst is triethylamine or triethylenediamine.

8. The nylon composite material according to any one of claims 1 to 7, characterized in that: The antioxidant is antioxidant 1010, antioxidant 1076, antioxidant 1098 or a phosphite antioxidant, preferably antioxidant 1010 or a phosphite antioxidant; And / or, the lubricant is one or more of silicone resin, polyethylene wax, stearamide, calcium stearate and pentaerythritol stearate, preferably silicone resin or polyethylene wax; And / or, the polyurethane is PA66 or PA6.

9. A method for preparing the nylon composite material according to any one of claims 1 to 8, characterized in that: The method comprises the following steps: mixing the polyurethane, toughening agent, antioxidant and lubricant, and adding the mixture from the main feeding port of a twin-screw extruder; mixing the GF-POSS-1 and GF-POSS-2, and adding the mixture from the side feeding port of the twin-screw extruder; and melt-blending, extruding and granulating to obtain the product.

10. The method for preparing a nylon composite material according to claim 9, characterized in that: The rotation speed of the twin-screw extruder is 200 rpm to 500 rpm, and the extrusion temperature is 230° C. to 280° C.

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