High-glowing filament, high-strength, halogen-free and flame-retardant glass fiber reinforced polyamide composite material and preparation method thereof

Abstract

The invention discloses a high-glowing filament, high-strength, halogen-free and flame-retardant glass fiber reinforced polyamide composite material and a preparation method thereof, and belongs to the field of polymer composite materials. The composite material comprises the following components in parts by weight: 20-60 parts of polyamide resin A, 0-20 parts of polyamide resin B, 0-20 parts of polyester resin, 10-50 parts of glass fibers, 10-20 parts of a halogen-free flame retardant, 1-15 parts of a flame retardant synergist A, 0-5 parts of a flame retardant synergist B and 0.5-5 parts of an auxiliary agent. The halogen-free flame-retardant glass fiber reinforced polyamide composite material obtained by the invention has excellent mechanical properties and flame retardancy under the interaction of various polyamides and polyester alloys and the synergistic effect of various flame-retardant synergists, and can reach the index of no ignition in the whole course of GWIT800 DEG C / 0.8 mm at the same time.

Description

Technical Field

[0001] The invention belongs to the technical field of polymer composite materials, and specifically relates to a high glow-wire, high-strength, halogen-free flame-retardant glass fiber reinforced polyamide composite material and a preparation method thereof. Background Art

[0002] In recent years, electronic and electrical equipment in the fields of home appliances, automobiles, consumer electronics, industrial production, etc. have caused local thermal runaway due to leakage, short circuit, breakdown, arcing, etc. during use, which subsequently caused the combustion of plastic materials and led to fires, causing serious harm to people's lives and production.

[0003] Polyamide (PA, commonly known as nylon) has a series of good comprehensive properties, including mechanical properties with a balance of rigidity and toughness, extremely high heat resistance, excellent chemical resistance, wear resistance and scratch resistance, etc., so it is widely used in home appliances, automobiles, consumer electronics, industry and other fields. However, the fire resistance of polyamide materials themselves is general. When encountering higher requirements for electrical insulation and fire prevention, it is often necessary to modify it to be flame retardant so that its flame retardant performance reaches UL-94V-0 or higher level, and the glow wire ignition temperature (GWIT) is 750℃ / 0.8mm and it will not burn throughout the whole process. In addition, in the field of home appliances, for some unattended insulating parts with a working current greater than 0.2A, even a high requirement of GWIT800℃ / 0.8mm that it will not burn throughout the whole process is proposed. Therefore, the glow wire temperature has become one of the important indicators for evaluating a polyamide flame retardant product. Although polyamide brominated flame retardant can well meet the high requirements of GWIT800℃ / 0.8mm, the disadvantages of brominated flame retardants such as corrosion of metal materials in high temperature and high humidity environments and low electrical insulation performance have made people urgently look for a more environmentally friendly and reliable polyamide flame retardant system.

[0004] Polyamide halogen-free flame retardant products have developed rapidly in recent years. They have stable flame retardant properties, extremely high electrical insulation properties and reliable long-term aging performance. However, their glow wire ignition temperature can only reach the GWIT750℃ / 0.8mm or GWIT775℃ / 0.8mm standard, which is difficult to meet the higher requirements of GWIT800℃ / 0.8mm, thus limiting their application in related fields.

[0005] Therefore, it is necessary to develop a glass fiber reinforced polyamide composite material with high glow wire, high strength and halogen-free flame retardant. Summary of the invention

[0006] One of the purposes of the present invention is to provide a high glow wire, high strength, halogen-free flame retardant glass fiber reinforced polyamide composite material to solve the problem that the glow wire of the existing halogen-free flame retardant polyamide material in the background technology cannot meet the GWIT800℃ / 0.8mm;

[0007] The second object of the present invention is to provide a method for preparing a high glow-wire, high-strength, halogen-free flame-retardant glass fiber reinforced polyamide composite material.

[0008] The purpose of the present invention can be achieved through the following technical solutions:

[0009] In the first aspect, a high glow-wire, high-strength, halogen-free flame-retardant glass fiber reinforced polyamide composite material comprises the following components in parts by weight:

[0010]

[0011] As a further embodiment of the present invention, the polyamide resin A is one or more of PA6, PA66, PA66 / 6, PA6 / 66, PA56, PA66 / 6I, PA66 / 6T, PA66 / 6T / 6I, PA610, PA612, PA1010, PA1012, PA11, PA12, PA1212, and MXD6;

[0012] Preferably, the polyamide resin A is one or more of PA6, PA66, PA66 / 6, PA6 / 66, PA56, PA66 / 6I, PA66 / 6T, PA66 / 6T / 6I, PA610, and PA612;

[0013] More preferably, the polyamide resin A is one of PA6, PA66, PA66 / 6, PA6 / 66, and PA56.

[0014] In the present invention, the polyamide resin A has excellent mechanical properties and provides good mechanical strength for the halogen-free flame-retardant glass fiber reinforced polyamide composite material.

[0015] As a further embodiment of the present invention, the polyamide resin B is one or more of PA66 / 6I, PA66 / 6T, PA6I / 6T, PA6T / 66, PA6T / 6I, PA6T / 6I / 66, PA6T / 5T, PA6T / 10T, and MXD6;

[0016] Preferably, the polyamide resin B is one or more of PA66 / 6I, PA66 / 6T, PA6I / 6T, and PA6T / 66;

[0017] More preferably, the polyamide resin B is one of PA66 / 6I, PA66 / 6T and PA6I / 6T.

[0018] In the present invention, the molecular chain segment of the polyamide resin B contains a certain aromatic ring structure, which can effectively improve the charring ability of the polyamide material, thereby improving the flame retardant efficiency of the polyamide halogen-free flame retardant material, and has a certain improvement effect on the glow-wire temperature of the polyamide halogen-free flame retardant material.

[0019] As a further embodiment of the present invention, the polyester resin is one or more of PET, PBT, PCT, PTT, PETG, PEN (polyethylene naphthalate), and PBN (polybutylene naphthalate);

[0020] Preferably, the polyester resin is one or more of PET, PBT, PCT, PTT, and PETG;

[0021] More preferably, the polyester resin is one of PET, PBT and PCT.

[0022] In the present invention, it is found in research that the polyester resin can improve the flame retardant properties and glow-wire temperature of the material after forming an alloy with polyamide.

[0023] As a further solution of the present invention, the glass fiber is a glass fiber dedicated to polyamide resin, and its fiber diameter can be selected to be 7 μm, 10 μm and 13 μm;

[0024] Preferably, the glass fiber has a diameter of 10 μm.

[0025] As a further embodiment of the present invention, the halogen-free flame retardant is one or more of aluminum phosphite, aluminum hypophosphite, monoethyl aluminum phosphite, diethyl aluminum phosphite, ethyl butyl aluminum phosphite, dibutyl aluminum phosphite, ethyl hexyl aluminum phosphite, butyl hexyl aluminum phosphite, ethyl octyl aluminum phosphite, sec-butyl aluminum ethyl phosphite, 1-ethyl butyl butyl aluminum phosphite, ethyl-1-methylpentyl aluminum phosphite, di-sec-butyl aluminum phosphite (di-1-methylpropyl aluminum phosphite), propyl hexyl aluminum phosphite, dihexyl aluminum phosphite, and hexyl nonyl aluminum phosphite;

[0026] Preferably, the halogen-free flame retardant is one or more of aluminum phosphite, aluminum hypophosphite, aluminum monoethyl phosphinate, aluminum diethyl phosphinate, aluminum ethylbutyl phosphinate, and aluminum dibutyl phosphinate;

[0027] More preferably, the halogen-free flame retardant is one of monoethyl aluminum phosphinate and diethyl aluminum phosphinate.

[0028] In the present invention, the halogen-free flame retardant is compounded into the polyamide system, which can improve the flame retardant properties of the polyamide material through the solid phase flame retardant mechanism, while having little effect on the mechanical properties of the material.

[0029] As a further embodiment of the present invention, the flame retardant synergist A is one or more of aluminum phosphite, aluminum hypophosphite, melamine polyphosphate (MPP), melamine pyrophosphate, melamine cyanurate (MCA), zinc borate, zinc stannate, zinc phosphate, zinc pyrophosphate, magnesium borate, and calcium stannate;

[0030] Preferably, the flame retardant synergist A is one or more of aluminum phosphite, aluminum hypophosphite, MPP, MCA, and zinc borate;

[0031] More preferably, the flame retardant synergist A is one of aluminum phosphite, MPP and MCA.

[0032] In the present invention, the flame retardant synergist A is often used in combination with a halogen-free flame retardant to improve the flame retardant efficiency of the halogen-free flame retardant, reduce costs, and enhance the mechanical properties of the material.

[0033] As a further solution of the present invention, when the flame retardant synergist A is compounded with the halogen-free flame retardant, the compounding ratio is 1:1-8.

[0034] Preferably, when the flame retardant synergist A is used in combination with the halogen-free flame retardant, the combination ratio is 1:2-4.

[0035] As a further embodiment of the present invention, the flame retardant synergist B is one or more of boehmite, wollastonite, silicon dioxide, magnesium oxide, calcium oxide, zinc oxide, aluminum oxide, potassium titanate whisker, basic magnesium sulfate whisker, zinc borate, aluminum borate, calcium carbonate, magnesium hydroxide, aluminum hydroxide, talc, mica, montmorillonite, diatomaceous earth, clay, and kaolin;

[0036] Preferably, the flame retardant synergist B is one or more of boehmite, wollastonite, zinc borate, aluminum borate, magnesium hydroxide, aluminum hydroxide, diatomaceous earth, and kaolin.

[0037] In the present invention, when the flame retardant synergist B is used together with the halogen-free flame retardant and the flame retardant synergist A, the flame retardant properties and the glow-wire temperature of the polyamide material can be improved to a certain extent.

[0038] As a further embodiment of the present invention, the auxiliary agent (conventional auxiliary agent) includes one or a combination of lubricants, mold release agents, nucleating agents, antioxidants, heat stabilizers, light stabilizers, and flow modifiers.

[0039] In a second aspect, a method for preparing a high glow-wire, high-strength, halogen-free flame-retardant glass fiber reinforced polyamide composite material comprises the following steps:

[0040] Polyamide resin A, polyamide resin B, polyester resin, flame retardant synergist A, flame retardant synergist B and additives are uniformly mixed in a mixer according to a proportion to obtain a mixture; the mixture is added into a twin-screw extruder through a main feeding port, a halogen-free flame retardant is added through a No. 1 side feeding port, and glass fiber is added through a No. 2 side feeding port, melt blended, extruded and granulated to obtain a high glow-wire, high-strength, halogen-free flame-retardant glass fiber reinforced polyamide composite material.

[0041] As a further solution of the present invention, the heating temperature range of the extruder is: 240-300°C in zones 1-3, 230-280°C in zones 4-7, 240-290°C in zones 8-10, and 240-300°C in the die.

[0042] Compared with the prior art, the present invention has the following beneficial effects:

[0043] The halogen-free flame-retardant glass fiber reinforced polyamide composite material obtained by the present invention has excellent mechanical properties and flame-retardant properties under the interaction of various polyamides and polyester alloys and the synergistic effect of various flame-retardant synergists, and can also achieve the GWIT800℃ / 0.8mm non-flammable index throughout the entire process.

[0044] All raw materials used in the present invention are in sufficient sources, and the raw materials can be domestically produced. The process conditions are simple and stable, and the excellent mechanical properties and flame retardant properties of the composite material are guaranteed while achieving a high glow-wire of the product. The overall cost performance of the material is still high, so it will have a good application prospect in the scenario where a household appliance connector requires a high glow-wire. DETAILED DESCRIPTION

[0045] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] In the following examples and comparative examples, the types and suppliers of the raw materials used are as follows:

[0047] Polyamide resin A: PA66, EPR27, Pingdingshan Shenma.

[0048] Polyamide resin B: MXD6, CX3005, Mitsubishi, Japan.

[0049] Polyester resin: PET, FG600, Yizheng Chemical Fiber.

[0050] Glass fiber: 10μm, ECS10-03-568H, Boulder.

[0051] Halogen-free flame retardant: aluminum diethylphosphinate, OP1230, Clariant.

[0052] Flame retardant synergist A: MPP, Melapur 200 / 70, BASF.

[0053] Flame retardant synergist B: kaolin, Translink(R)445, BASF.

[0054] Antioxidants: 1098 and 168 are both commercially available.

[0055] Lubricant: BN-500, Qingdao Bangni Chemical Co., Ltd.

[0056] The models and suppliers of the above raw materials are only for illustrating the sources and components of the raw materials used in the experiments of the present invention so as to fully disclose the information, and do not mean that the present invention cannot be realized by using other raw materials of the same type or raw materials provided by other suppliers.

[0057] Embodiment 1-6

[0058] The components and weight proportions of the composite materials in Examples 1-6 are shown in Table 1, and the components are weighed according to the weight proportions of the components in Table 1; the preparation method is as follows:

[0059] Polyamide resin A (PA66), polyamide resin B (MXD6), polyester resin (PET), flame retardant synergist A (MPP), flame retardant synergist B (kaolin) and conventional additives (antioxidant 1098, antioxidant 168, lubricant BN-500) are uniformly mixed in a high-speed mixer according to a proportion to obtain a mixture; the mixture is added into a twin-screw extruder through a main feeding port, a halogen-free flame retardant (aluminum diethylphosphinate) is added through a No. 1 side feeding port, and glass fiber (10 μm) is added through a No. 2 side feeding port, melt blended, and extruded into granules. The heating temperature range of the extruder is: 240-300° C. in zones 1-3, 230-280° C. in zones 4-7, 240-290° C. in zones 8-10, and 240-300° C. in a die; a high glow-wire, high-strength, halogen-free flame-retardant glass fiber reinforced polyamide composite material is obtained.

[0060] Table 1

[0061]

[0062]

[0063] Comparative Examples 1-3

[0064] The components and weight proportions of the composite materials in Comparative Examples 1-3 are shown in Table 2, and the components are weighed according to the weight proportions of the components in Table 2; the preparation method is the same as that of Examples 1-6.

[0065] Table 2

[0066]

[0067]

[0068] The polyamide composite materials prepared in Examples 1-6 and Comparative Examples 1-3 were tested for performance, and the test methods or standards were as follows:

[0069] (1) Mechanical property test: The polyamide composite material was dried at 120 °C for 4 h and then tested according to standard injection molding. The tensile strength test was performed according to ISO 527, the flexural strength and flexural modulus tests were performed according to ISO 178, and the notched impact strength test was performed according to ISO 179.

[0070] (2) Flame retardant performance test: The polyamide composite material was dried at 120°C for 4 h and then tested by standard injection molding. The flame retardant performance of the sample with a thickness of 0.8 mm was tested according to the UL-94 standard.

[0071] (3) Glow-wire (GWIT) test: The polyamide composite material of the embodiment or comparative example was dried at 120° C. for 4 h and then tested according to standard injection molding. A glow-wire (GWIT) test was performed on a sample with a thickness of 0.8 mm according to the IEC 60695-2-13 standard.

[0072] The above test results are shown in Table 3.

[0073] Table 3

[0074]

[0075]

[0076] Combining the material ratios of Table 1 and Table 2 with the results of Table 3, it can be seen that Comparative Examples 1 and 2 show that MPP compounding plays a very important role in improving the flame retardant efficiency of OP1230 in polyamide. Comparative Example 3 adds 2 parts of kaolin alone, which has no effect on the flame retardant properties of the material, but also cannot improve the glow-wire temperature of the material. In Examples 2 and 3, after the introduction of PET and MXD6, the glow-wire temperature of the polyamide composite material is increased to 775°C, and the mechanical properties of Example 2 are improved to a certain extent compared with Comparative Example 3, because the alloy formed by MXD6 and PA66 can improve the mechanical properties of the material. In Examples 1, 4, 5, and 6, the compounding ratio of MXD6, PET, and kaolin is changed, and the flame retardant properties of the polyamide composite material are qualified, and at the same time, the requirements of GWIT800°C / 0.8mm can be met, which shows that the compounding method can effectively improve the glow-wire temperature of the halogen-free flame-retardant polyamide system within a wider compounding ratio range.

[0077] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0078] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A high glow-wire, high-strength, halogen-free flame-retardant glass fiber reinforced polyamide composite material, characterized in that: By mass, it includes the following components:

2. The high glow-wire, high-strength, halogen-free flame-retardant glass fiber reinforced polyamide composite material according to claim 1, characterized in that: The polyamide resin A is one or more of PA6, PA66, PA66 / 6, PA6 / 66, PA56, PA66 / 6I, PA66 / 6T, PA66 / 6T / 6I, PA610, PA612, PA1010, PA1012, PA11, PA12, PA1212, and MXD6.

3. The high glow-wire, high-strength, halogen-free flame-retardant glass fiber reinforced polyamide composite material according to claim 1, characterized in that: The polyamide resin B is one or more of PA66 / 6I, PA66 / 6T, PA6I / 6T, PA6T / 66, PA6T / 6I, PA6T / 6I / 66, PA6T / 5T, PA6T / 10T, and MXD6.

4. The high glow-wire, high-strength, halogen-free flame-retardant glass fiber reinforced polyamide composite material according to claim 1, characterized in that: The polyester resin is one or more of PET, PBT, PCT, PTT, PETG, PEN, and PBN.

5. The high glow-wire, high-strength, halogen-free flame-retardant glass fiber reinforced polyamide composite material according to claim 1, characterized in that: The halogen-free flame retardant is one or more of aluminum phosphite, aluminum hypophosphite, monoethyl aluminum phosphite, diethyl aluminum phosphite, ethyl butyl aluminum phosphite, dibutyl aluminum phosphite, ethyl hexyl aluminum phosphite, butyl hexyl aluminum phosphite, ethyl octyl aluminum phosphite, sec-butyl aluminum ethyl phosphite, 1-ethyl butyl butyl aluminum phosphite, ethyl-1-methylpentyl aluminum phosphite, di-sec-butyl aluminum phosphite (di-1-methylpropyl aluminum phosphite), propyl hexyl aluminum phosphite, dihexyl aluminum phosphite, and hexyl nonyl aluminum phosphite.

6. The high glow-wire, high-strength, halogen-free flame-retardant glass fiber reinforced polyamide composite material according to claim 1, characterized in that: The flame retardant synergist A is one or more of aluminum phosphite, aluminum hypophosphite, MPP, melamine pyrophosphate, MCA, zinc borate, zinc stannate, zinc phosphate, zinc pyrophosphate, magnesium borate, and calcium stannate; And / or, the usage ratio of the flame retardant synergist A to the halogen-free flame retardant is 1:1-8.

7. The high glow-wire, high-strength, halogen-free flame-retardant glass fiber reinforced polyamide composite material according to claim 1, characterized in that: The flame retardant synergist B is one or more of boehmite, wollastonite, silicon dioxide, magnesium oxide, calcium oxide, zinc oxide, aluminum oxide, potassium titanate whisker, basic magnesium sulfate whisker, zinc borate, aluminum borate, calcium carbonate, magnesium hydroxide, aluminum hydroxide, talc, mica, montmorillonite, diatomaceous earth, clay, and kaolin.

8. The high glow-wire, high-strength, halogen-free flame-retardant glass fiber reinforced polyamide composite material according to claim 1, characterized in that: The auxiliary agent includes one or a combination of lubricants, mold release agents, nucleating agents, antioxidants, heat stabilizers, light stabilizers, and flow modifiers.

9. A method for preparing the high glow-wire, high-strength, halogen-free flame-retardant glass fiber reinforced polyamide composite material as claimed in claim 1, characterized in that: The following steps are involved: The polyamide resin A, the polyamide resin B, the polyester resin, the flame retardant synergist A, the flame retardant synergist B and the additives are uniformly mixed according to a proportion to obtain a mixture; The mixed material is added into the twin-screw extruder through the main feeding port, the halogen-free flame retardant is added through the No. 1 side feeding port, and the glass fiber is added through the No. 2 side feeding port, melt blended, extruded and granulated to obtain a high glow-wire, high-strength, halogen-free flame-retardant glass fiber reinforced polyamide composite material.

10. The method for preparing a high glow-wire, high-strength, halogen-free flame-retardant glass fiber reinforced polyamide composite material according to claim 9, characterized in that: The heating temperature range of the extruder is: 240-300℃ for zones 1-3, 230-280℃ for zones 4-7, 240-290℃ for zones 8-10, and 240-300℃ for the die.

Images