Polyamide composite material, and preparation method therefor and use thereof

Abstract

Disclosed in the present invention are a polyamide composite material, and a preparation method therefor and the use thereof. The polyamide composite material comprises the following components in parts by weight: 28-75 parts of a polyamide resin, 3-10 parts of a gas phase reinforcing agent, 8-22 parts of an organic phosphorus flame retardant, 3-12 parts of a synergistic flame retardant and 8-32 parts of reinforcing fibers, wherein the gas phase reinforcing agent comprises a compound containing a sulfonamide group, and melem and / or melam, and the mass ratio of the compound containing the sulfonamide group to the melem and / or melam is (0.5-3): 1. According to the present invention, the compound containing the sulfonamide group and the melem and / or the melam in a specific mass ratio are added into the polyamide resin as the gas phase reinforcing agent, so the glow-wire performance of the composite material can be improved, and the composite material has relatively good mechanical performance and forms fewer mold deposits.

Description

A polyamide composite material, its preparation method and application Technical Field

[0001] This invention relates to the field of engineering plastics technology, and more specifically, to a polyamide composite material, its preparation method, and its application. Background Technology

[0002] Polyamide resins possess excellent mechanical properties, outstanding barrier properties, good heat resistance, abrasion resistance, and chemical resistance, making them widely used in the machinery manufacturing, power tool, electronics, and transportation industries. In the manufacture of electronic products, polyamide materials must not only meet basic physical and chemical performance requirements but also possess certain fire safety properties to comply with increasingly stringent industry standards and safety regulations. Traditionally, halogenated flame retardants have been widely used due to their highly effective flame retardancy; however, their non-environmentally friendly properties and low CTI values ​​limit their further application.

[0003] Halogen-free flame-retardant reinforced polyamide materials have gained widespread popularity in the electronics and electrical appliance fields, especially in the connector industry, in recent years. With the rapid development of the home appliance connector industry towards higher voltage and higher safety, more stringent requirements have been placed on the electrical and flame-retardant properties of materials. For example, the glow wire test (GWIT) according to IEC 60695-2-11 requires the material to be tested at or above 775°C to ensure good flame-retardant performance under extreme conditions. Current technologies often improve glow wire flame-retardant performance by adjusting the type and content of flame retardants or by using flame retardant compounding techniques. However, while increasing the flame retardant content can effectively improve glow wire flame-retardant performance, it can cause mold fouling during extrusion and injection molding, as well as flame retardant precipitation during use, affecting the long-term stability and safety of the product. Furthermore, while using inorganic fillers such as magnesium hydroxide can improve flame-retardant performance to some extent, it often adversely affects the mechanical properties of the material, limiting its application in high-precision and high-strength applications. Summary of the Invention

[0004] The purpose of this invention is to overcome the defects or deficiencies of the halogen-free flame-retardant reinforced polyamide composite materials in the prior art, and to provide a polyamide composite material.

[0005] Another object of the present invention is to provide a method for preparing the polyamide composite material.

[0006] Another object of the present invention is to provide applications of the polyamide composite material.

[0007] To achieve the above objectives, the present invention employs the following technical solution:

[0008] A polyamide composite material comprising the following components in parts by weight:

[0009] 28-75 parts of polyamide resin;

[0010] 3-10 parts of vapor phase enhancer;

[0011] 8-22 parts of organophosphorus flame retardant;

[0012] 3-12 parts of synergistic flame retardant;

[0013] 8-32 parts of reinforcing fiber;

[0014] The gas-phase enhancer comprises a compound containing a sulfonamide group, as well as melamine and / or melamine, wherein the mass ratio of the compound containing the sulfonamide group to the mass of melamine and / or melamine is (0.5~3):1.

[0015] This invention provides a polyamide composite material. By using a compound containing sulfonamide groups and melamine and / or melamine as a gas phase reinforcing agent in a specific mass ratio, free radicals can be quenched, reducing the amount of initial free radicals generated in the condensed phase. The sulfonamide group compound can prolong the glow wire ignition time, and melamine and / or melamine can dilute the concentration of combustible gas, delaying the process of combustible gas reaching the critical explosion concentration. Furthermore, by adjusting the ratio of the two, the glow wire flame retardant performance of the composite material can be significantly improved in a system where the condensed phase of organophosphorus flame retardant forms char and flame retardant residues without increasing scale buildup, in the case of organophosphorus flame retardant.

[0016] It should be noted that, in the polyamide composite material described in this invention, the polyamide resin content is preferably not less than 25 wt%.

[0017] In this invention, the mass ratio of the sulfonamide group-containing compound to the mass of melamine and / or melamine is (0.5~3):1, for example, but not limited to 0.5:1, 1:1, 1.5:1, 2:1, 2.5:1 or 3:1, and specific values ​​between the above points. Due to space limitations and for the sake of brevity, the specific values ​​included in the range are not exhaustively listed in this invention.

[0018] Furthermore, the mass ratio of the sulfonamide-containing compound to the mass of melamine and / or melamine is (1~2):1.

[0019] The gas phase enhancer described in this invention is 3 to 10 parts, for example, but not limited to, 3 parts, 3.2 parts, 3.5 parts, 3.8 parts, 4 parts, 4.2 parts, 4.5 parts, 4.8 parts, 5 parts, 5.2 parts, 5.5 parts, 5.8 parts, 6 parts, 6.2 parts, 6.5 parts, 6.8 parts, 7 parts, 7.2 parts, 7.5 parts, 7.8 parts, 8 parts, 8.2 parts, 8.5 parts, 8.8 parts, 9 parts, 9.2 parts, 9.5 parts, 9.8 parts, or 10 parts, etc., and specific values ​​between the above-mentioned values. Due to space limitations and for the sake of brevity, the specific values ​​included in the range are not exhaustively listed in this invention.

[0020] Furthermore, the structural formula of the compound containing the sulfonamide group is as follows: Wherein, R1 is selected from C1~C4 alkyl, phenyl, and aromatic substituents; R2 is selected from hydrogen, C1~C4 alkyl, C1~C4 alkylamino, phenyl, aromatic substituents, and C4~C5 heterocyclic groups;

[0021] Furthermore, R1 is selected from phenyl or aromatic substituents; R2 is selected from phenyl or aromatic substituents.

[0022] In some preferred embodiments, the aromatic substituent is tolyl or chlorophenyl.

[0023] Furthermore, the initial decomposition temperature of the sulfonamide-containing compound is ≥300°C.

[0024] Specifically, the initial decomposition temperature of the sulfonamide-containing compound is ≥300°C, such as, but not limited to, ≥300°C, 305°C, 310°C, 315°C, 320°C, 325°C, 330°C, 335°C, 340°C, 345°C, 350°C, 355°C, or 360°C, as well as specific values ​​between the above values. Due to space limitations and for the sake of brevity, the specific values ​​included in the range will not be exhaustively listed in this invention.

[0025] Furthermore, the initial decomposition temperature of the sulfonamide-containing compound is 310~340℃.

[0026] Specifically, the test standard for the initial decomposition temperature of the sulfonamide compound is GB / T 33047.1-2016.

[0027] Specifically, the sulfonamide-containing compound includes one or more of N-(3-piperidinyl)methanesulfonamide, N-(2-aminoethyl)-4-methylbenzenesulfonamide, N-(4-chlorophenyl)benzenesulfonamide, N-phenylbenzenesulfonamide, or benzenesulfonamide.

[0028] Furthermore, the average particle size of the meliamine and / or meliamine is ≤15μm.

[0029] Specifically, the average particle size of the melamine and / or melamine is 5~15 μm.

[0030] Furthermore, the initial decomposition temperature of the melamine and / or melamine is ≥375°C.

[0031] Furthermore, the initial decomposition temperature of the melamine and / or melamine is 380~430℃.

[0032] Specifically, the test standard for the initial decomposition temperature of the melamine and / or melamine is GB / T 33047.1-2016.

[0033] Further, the polyamide composite material comprises the following components calculated in parts by weight:

[0034] 40-65 parts of polyamide resin;

[0035] 5-7 parts of vapor phase enhancer;

[0036] 12-20 parts of organophosphorus flame retardant;

[0037] Synergistic flame retardant 4-8 parts;

[0038] 15-28 parts of reinforcing fiber.

[0039] Furthermore, the organophosphorus flame retardant includes aluminum diethylphosphonate, aluminum dipropylphosphonate, aluminum phenylphosphonate, aluminum methylethylphosphonate, aluminum methylphenylphosphonate, and aluminum carboxyethylphenylphosphonate.

[0040] Furthermore, the synergistic flame retardant includes melamine polyphosphate and / or zinc borate.

[0041] Furthermore, the average particle size of the synergistic flame retardant is 2~5μm.

[0042] Specifically, the melamine polyphosphate includes one or more of melamine polyphosphate, melamine aluminum polyphosphate, melamine magnesium polyphosphate, or melamine zinc polyphosphate.

[0043] Furthermore, the reinforcing fibers include glass fibers and / or carbon fibers.

[0044] Furthermore, the average length of the reinforcing fiber is 3~6 mm.

[0045] Furthermore, the polyamide resin includes one or more of aliphatic polyamide resins and / or aromatic polyamide resins.

[0046] Specifically, the aliphatic polyamide resin is one or more of PA66, PA610, PA612, PA1010, PA1012, PA1212, PA6, PA7, PA11, PA12, and PAPACM12.

[0047] The aromatic polyamide resin is one or more of PA6T, PA9T, PA10T, PA11T, PA12T, PA13T, PA6T / 6I, PA6T / 6I / 66, PA6I, PA6I / 6T, PA10T / 66, PA10T / 1010, PA10T / 10I, and PPTA.

[0048] Furthermore, the relative viscosity of the polyamide resin is 2.0~2.8.

[0049] Furthermore, the test standard for the relative viscosity is ASTM D789-19.

[0050] Furthermore, the polyamide composite material also includes 0.1 to 5 parts of additives.

[0051] Furthermore, the additive is an antioxidant and / or a lubricant.

[0052] In this invention, commonly used antioxidants can be selected according to existing technology, such as, but not limited to, one or more of hindered phenolic antioxidants, phosphite antioxidants, diphenylamine antioxidants, or thioether antioxidants.

[0053] Specifically, the hindered phenolic antioxidant is one or more of N,N'-hexamethylene bis(3,5-di-tert-butyl-4-hydroxyphenylpropionamide) (Irganox 1098), pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (Irganox 1010), 1,6-hexanediol bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (Irganox 259), octadecyl β-(4-hydroxy-3,5-di-tert-butylphenyl)propionate (Irganox 1076), or 3,9-bis{2-[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)acrylic acid]-1,1-dimethyl}-2,4,8,10-tetraoxaspirocycloundecane (ADK AO-80).

[0054] The phosphite antioxidant is one or more of tris(2,4-di-tert-butylphenyl) phosphite (Irganox 168), bis(2,6-di-tert-butyl-4-tolyl) pentaerythritol phosphite (PEP-36), or 627A.

[0055] The diphenylamine antioxidant is 4,4'-bis(α,α'-dimethylbenzyl)diphenylamine.

[0056] The thioether antioxidant is one or more of distearate thiodipropionate, dilaurate thiodipropionate, or pentaerythritol-based dodecathiopropyl ester.

[0057] In this invention, commonly used lubricants can be selected based on existing technology. For example, but not limited to, one or more of stearic acid lubricants, polyethylene lubricants, amide lubricants, paraffin lubricants, ester lubricants, or silicone lubricants.

[0058] Specifically, the stearic acid lubricant may be calcium stearate and / or zinc stearate.

[0059] The polyethylene lubricant may be polyethylene wax.

[0060] The amide lubricant may be one or more of oleamide lubricants, EBS amide lubricants, or erucamide lubricants.

[0061] The ester lubricant may be an aliphatic stearate, such as oleic acid-based aliphatic polyester and / or erucic acid-based aliphatic polyester.

[0062] The silicone lubricant may be polydimethylsiloxane.

[0063] This invention also protects a method for preparing the above-mentioned polyamide composite material, comprising the following steps:

[0064] The components are mixed evenly to obtain a premix, and the premix is ​​melt-blended and extruded to obtain a voltage-resistant nylon composition.

[0065] Furthermore, the extrusion granulation is carried out in a twin-screw extruder.

[0066] Furthermore, the length-to-diameter ratio of the screw in the twin-screw extruder is 40 to 48:1.

[0067] Furthermore, the barrel temperature of the twin-screw extruder is 270–300°C.

[0068] Furthermore, the screw speed of the twin-screw extruder is 150–400 rpm.

[0069] This invention also protects the application of the above-mentioned polyamide composite material in the field of electronics and electrical engineering. In particular, it protects the manufacture of parts with good glow wire flame retardant properties. Specifically, it protects applications in the manufacture of materials such as connectors.

[0070] Compared with the prior art, the beneficial effects of the present invention are:

[0071] This invention provides a polyamide composite material. By adding a compound containing a sulfonamide group and melamine and / or melamine to the polyamide resin and adjusting the ratio of the two, the hot wire performance of the polyamide composite material can be improved, and the molding fouling is reduced, resulting in better mechanical properties. Embodiments of the present invention

[0072] The present invention will be further described below with reference to specific embodiments, but the embodiments do not limit the present invention in any way. Unless otherwise stated, the raw materials and reagents used in the embodiments of the present invention are conventionally purchased raw materials and reagents.

[0073] 1. Raw materials used in the various embodiments and comparative examples of the present invention:

[0074] Polyamide resin:

[0075] Polyamide resin 1: PA66, PA66 U4800 NC01 SS, purchased from Invista;

[0076] Polyamide resin 2: PA56, ECOPENT ® 1273, purchased from Cathay Biomaterials Co., Ltd.;

[0077] Vapor phase enhancer:

[0078] Vapor phase enhancer A1: N-(2-aminoethyl)-4-methylbenzenesulfonamide, CAS No. 14316-16-6, purchased from Aladdin;

[0079] Vapor phase enhancer A2: N-(4-chlorophenyl)benzenesulfonamide, CAS No. 4750-28-1, purchased from Aladdin;

[0080] Vapor phase enhancer A3: N-(3-piperidinyl)methanesulfonamide, CAS No. 944068-21-7, purchased from Aladdin;

[0081] Vapor phase enhancer B1: Honey bleach, Sichuan Fine Chemical Research and Design Institute;

[0082] Vapor phase enhancer B2: Meleramine, Shaanxi Didu Pharmaceutical Chemical Co., Ltd.;

[0083] Magnesium hydroxide, Aitemag® 10, Jiangsu Aitemag Flame Retardant Materials Co., Ltd.;

[0084] Organophosphorus flame retardant: aluminum diethylphosphite, Exolit OP 1230, purchased from Clariant;

[0085] Synergistic flame retardants:

[0086] Synergistic flame retardant 1: melamine polyphosphate, Bubit 3141, purchased from Bode;

[0087] Synergistic flame retardant 2: Zinc borate, HT-261, Shandong Taixing New Material Co., Ltd.;

[0088] Reinforcing fiber: Glass fiber, S1HM435TM-10-3, average length 3mm, purchased from Taishan Glass Fiber Co., Ltd.

[0089] Additives:

[0090] Antioxidant: Inganox@1098; Lubricant: LOXIOL G32; Both antioxidants and lubricants are commercially available, and the same antioxidants and lubricants were used in parallel experiments of the examples and comparative examples.

[0091] 2. The polyamide composite materials described in each embodiment and comparative example were prepared according to the formulations in Tables 1-2 and prepared using the following methods:

[0092] The components are mixed evenly to obtain a premix, which is then fed into a twin-screw extruder for melt blending, extrusion granulation, and polyamide composite material. The twin-screw extruder has a screw length-to-diameter ratio of 40 to 48:1, a barrel temperature of 270 to 300°C, and a screw speed of 150 to 400 rpm.

[0093] 3. Testing Method:

[0094] (1) Flame retardant performance test: The polyamide composite materials in each example and comparative example were injection molded into specimens with dimensions of 125mm×13mm×1.0mm, and flame retardant tests were conducted in accordance with UL 94-2013 standard;

[0095] (2) Glow wire ignition temperature test: The polyamide composite materials in each example and comparative example were injection molded into square plates of 60mm×60mm×1mm and tested in accordance with IEC 60695-2-13:2021 standard;

[0096] (3) Mold fouling test: The polyamide composite materials in each example and comparative example were injection molded at 300°C. When 200 molds were continuously injection molded, the mold fouling on the mold was collected and weighed.

[0097] (4) Notched impact strength test: The polyamide composite materials in each example and comparative example were injection molded into 80mm×10mm×4mm specimens and tested according to ISO 180:2019 standard. The notch type was type A.

[0098] Examples 1-12 and Comparative Examples 1-4

[0099] Table 1. Amount (parts by weight) and properties of each component in the polyamide composites of Examples 1-12

[0100]

[0101] Table 2. Amounts (parts by weight) and properties of each component in the polyamide composites of Comparative Examples 1-4

[0102]

[0103] As shown in Table 1, the polyamide composite material prepared by this invention exhibits good glow wire flame retardant properties, minimal mold fouling, and superior mechanical properties. Specifically, it achieves a 1.0 mm V-0 rating at a glow wire temperature of not less than 775℃, with mold fouling not exceeding 2.6 mg and a notched impact strength not less than 11.5 kJ / m². 2 .

[0104] As can be seen from Examples 1-4, by introducing compounds containing sulfonamide groups and compounding them with melamine and / or melamine, the performance of glow wire can be effectively improved. The polyamide composite material prepared with a mass ratio of (1-2):1 has better overall performance.

[0105] As can be seen from Comparative Examples 1 and 2, if the proportion of vapor phase reinforcing agent is too low or too high, the hot wire performance of the obtained polyamide composite material is reduced, and when the amount of vapor phase reinforcing agent B is high, mold fouling increases.

[0106] As can be seen from Comparative Example 3, if other flame retardants are used as fillers, the performance requirements of the glow wire cannot be met, and the mechanical properties will decrease.

[0107] As can be seen from Comparative Example 4, if no vapor phase reinforcing agent is added and the content of the synergistic flame retardant is increased, the decomposition of the synergistic flame retardant will lead to an increase in mold fouling and will have limited effect on improving the performance of the glow wire.

[0108] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A polyamide composite, characterized in that, Includes the following components, calculated in parts by weight: 28-75 parts of polyamide resin; 3-10 parts of vapor phase enhancer; 8-22 parts of organophosphorus flame retardant; 3-12 parts of synergistic flame retardant; 8-32 parts of reinforcing fiber; The gas-phase enhancer comprises a compound containing a sulfonamide group, as well as melamine and / or melamine, wherein the mass ratio of the compound containing the sulfonamide group to the mass of melamine and / or melamine is (0.5~3):

1.

2. The polyamide composite according to claim 1, characterized in that, The mass ratio of the sulfonamide-containing compound to the mass of melamine and / or melamine is (1~2):

1.

3. The polyamide composite material according to claim 1 or 2, characterized in that, The structural formula of the compound containing a sulfonamide group is ; wherein R1 is selected from C1-C4 alkyl, phenyl, aromatic substituent; R2 is selected from hydrogen, C1-C4 alkyl, C1-C4 alkylamino, phenyl, aromatic substituent, C4-C5 heterocyclic group; preferably, R1 is selected from phenyl, aromatic substituent; R2 is selected from phenyl, aromatic substituent.

4. The polyamide composite according to claim 1 or 2, characterized in that, The sulfonamide-containing compound includes one or more of N-(3-piperidinyl)methanesulfonamide, N-(2-aminoethyl)-4-methylbenzenesulfonamide, N-(4-chlorophenyl)benzenesulfonamide, N-phenylbenzenesulfonamide, or benzenesulfonamide.

5. The polyamide composite material according to claim 1, characterized in that, The organophosphorus flame retardants include aluminum diethylphosphonate, aluminum dipropylphosphonate, aluminum phenylphosphonate, aluminum methylethylphosphonate, aluminum methylphenylphosphonate, and aluminum carboxyethylphenylphosphonate.

6. The polyamide composite material according to claim 1, characterized in that, The synergistic flame retardants include melamine polyphosphate and / or zinc borate.

7. The polyamide composite material according to claim 1, characterized in that, The reinforcing fibers include glass fibers and / or carbon fibers.

8. The polyamide composite material according to claim 1, characterized in that, It also includes 0.1 to 5 parts of adjuvants.

9. A method for preparing the polyamide composite material according to any one of claims 1 to 8, characterized in that, Includes the following steps: The components are mixed evenly to obtain a premix, and the premix is ​​melt-blended and extruded to obtain a voltage-resistant nylon composition.

10. The application of the polyamide composite material according to any one of claims 1 to 8 in the field of electronics and electrical engineering.

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