Organic phosphine flame-retardant nylon material, preparation method and application thereof

Abstract

The application provides an organic phosphine flame-retardant nylon material and a preparation method and application thereof, and belongs to the technical field of high polymer materials. By introducing specific acid absorbents and flame-retardant stabilizers into the organic phosphine flame-retardant nylon material, the two synergistically act, can significantly improve the yellowing of the material in the processing process under the premise of not reducing the mechanical properties and the flame-retardant properties of the material, widen the processing window of the organic phosphine flame-retardant nylon material, and solve the problems caused by long-period injection molding processing of large parts.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of high polymer alloy materials, in particular to an organic phosphine flame-retardant nylon material and a preparation method and application thereof. BACKGROUND

[0002] With the development of the economic society, environmental protection is paid more and more attention, and the environmental protection requirement for materials is also higher and higher. Traditional halogen flame retardants have a wide application in the field of electronic and electrical, especially household connector, due to high flame-retardant efficiency, moderate price and good hot wire performance. At present, the halogen-free flame-retardant system mainly used in flame-retardant nylon includes melamine cyanurate (MCA), red phosphorus and organic phosphine (nitrogen phosphorus system). The organic phosphine flame-retardant system is gradually favored by people due to good mechanical properties, electrical properties and full-color matching characteristics.

[0003] However, the most widely used diethyl aluminum phosphite in the organic phosphine flame retardant needs to be added in a proportion of 10-15 parts, and a synergist is often needed to achieve UL94 V-0 flame retardant grade. The organic phosphine flame retardant itself is acidic and has poor thermal stability, which can cause the system to have strong acidity during extrusion processing and injection molding. When processing or injection molding materials of natural color or light color, yellowing problem is prone to occur, and the yellowing phenomenon is more obvious when the material is stored for a certain period of time.

[0004] Patent CN114874616A discloses a halogen-free flame-retardant yellowing-resistant low-mold PA66 composite material and a preparation method thereof. In the OP, MPP and zinc borate compound flame-retardant system, a multi-hydroxyl component (dipentaerythritol) and a metal oxide (zinc oxide) are added to achieve good yellowing resistance and reduce injection molding mold dirt. However, the introduction of the metal oxide further reduces the toughness of the organic phosphine system and causes a certain loss of mechanical properties. SUMMARY

[0005] The application aims to overcome the shortcomings of the prior art and provide an organic phosphine flame-retardant nylon material. By adding a specific acid absorbent and a flame-retardant stabilizer in the organic phosphine flame-retardant nylon material, the yellowing of the material during processing can be significantly improved without reducing the mechanical properties and flame-retardant properties of the material, the processing window of the organic phosphine flame-retardant nylon material is widened, and the problems caused by long-period injection molding of large parts are solved.

[0006] To achieve the above-mentioned purpose, the technical scheme adopted by the application is as follows: an organic phosphine flame-retardant nylon material, which comprises the following components in parts by weight: 48-72 parts of a polyamide resin, 15-26 parts of an organic phosphine flame retardant, 14-31 parts of glass fiber, 0.08-5.2 parts of a flame-retardant stabilizer and 0.08-1.1 parts of an acid absorbent.

[0007] The flame-retardant stabilizer is a binary copolymer or a ternary copolymer, the binary copolymer is one of unsaturated hydrocarbon-unsaturated fatty acid copolymer, unsaturated hydrocarbon-unsaturated carboxylic acid ester copolymer, and the ternary copolymer is a copolymer of olefin, unsaturated fatty acid and aliphatic unsaturated ester; the acid-adsorbing agent is a metal hydroxide.

[0008] In the present application, the weight parts of the flame-retardant stabilizer can be 0.08 parts, 0.1 parts, 0.2 parts, 0.5 parts, 0.8 parts, 1 parts, 1.5 parts, 2.0 parts, 2.5 parts, 3 parts, 3.5 parts, 4.0 parts, 4.5 parts, 5.0 parts, 5.2 parts, and the present application is not limited thereto.

[0009] In the present application, the weight parts of the acid-adsorbing agent can be 0.08 parts, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, 1 parts, 1.1 parts, and the present application is not limited thereto.

[0010] In the organic phosphine flame-retardant nylon material of the present application, by introducing specific acid-adsorbing agents and flame-retardant stabilizers, on the one hand, the flame-retardant stabilizers can play a certain protective role in flame retardation, and on the other hand, the acid-adsorbing agents can neutralize part of the acidity in the organic phosphine flame-retardant nylon material system, and the two synergistically act to significantly improve the yellowing of the material during processing, broaden the processing window of the organic phosphine flame-retardant nylon material, and solve the problems caused by large parts and long-period injection molding. Too much or too little addition of the acid-adsorbing agent and the flame-retardant stabilizer in the organic phosphine flame-retardant nylon material will both cause an increase in the yellowing of the product.

[0011] Specifically, the weight parts of the polyamide resin can be 50 parts, 53 parts, 55 parts, 58 parts, 60 parts, 62 parts, 65 parts, 67 parts, 70 parts, but are not limited to the listed values, and other unlisted values within the scope of the present disclosure are also applicable.

[0012] Specifically, the weight parts of the organic phosphine flame retardant can be 15 parts, 17 parts, 20 parts, 22 parts, 24 parts, 26 parts, but are not limited to the listed values, and other unlisted values within the scope of the present disclosure are also applicable.

[0013] Specifically, the weight parts of the glass fiber can be 15 parts, 18 parts, 20 parts, 22 parts, 24 parts, 26 parts, 28 parts, 30 parts, but are not limited to the listed values, and other unlisted values within the scope of the present disclosure are also applicable.

[0014] In one embodiment, the mass ratio of the acid-adsorbing agent and the flame-retardant stabilizer is 1:2-2:1, for example, it can be 1:2, 1:1.8, 1:1.5, 1:1.3, 1:1, 1.2:1, 1.5:1, 1.7:1, 2:1, but the present application is not limited thereto.

[0015] In the present application, the acid-adsorbing agent and the flame-retardant stabilizer in a suitable ratio can significantly improve the yellowing of the organic phosphine flame-retardant nylon material. If the mass ratio of the acid-adsorbing agent and the flame-retardant stabilizer is too large or too small, the product cannot obtain the best mechanical properties, flame-retardant properties and yellowing resistance effect.

[0016] In the present application, the binary copolymer is at least one of ethylene-methyl acrylic acid copolymer, ethylene-methyl acrylate copolymer and ethylene-acrylic acid copolymer. The binary copolymer is preferably ethylene-methyl acrylate copolymer.

[0017] In the present application, the ternary copolymer is at least one of ethylene-methyl acrylic acid-acrylate copolymer, ethylene-methyl acrylic acid-acrylate ionomer, ethylene-propylene-non-conjugated diene copolymer and ethylene-methyl acrylate-glycidyl methacrylate. The ternary copolymer is preferably ethylene-methyl acrylic acid-acrylate copolymer.

[0018] In the present application, when the binary copolymer or the ternary copolymer is the above-mentioned substance, the obtained organic phosphine flame-retardant nylon material has better performance.

[0019] In one embodiment, the metal hydroxide is at least one of magnesium hydroxide, zinc hydroxide and zirconium hydroxide.

[0020] In the present application, compared with other metal hydroxides, at least one of magnesium hydroxide, zinc hydroxide and zirconium hydroxide can further increase the yellowing resistance effect of the product.

[0021] Specifically, the particle size D50 of the metal hydroxide is 0.5-2 μm; the particle size D50 is obtained by using a laser particle size instrument.

[0022] In one embodiment, the glass fiber is alkali-free chopped glass fiber, specifically, the alkali-free chopped glass fiber in the present application is hydrolysis-resistant alkali-free chopped glass fiber, preferably, the hydrolysis-resistant alkali-free chopped glass fiber has a chopped length of 3-4.5 mm and a diameter of 9-13 μm.

[0023] In one embodiment, the polyamide resin is at least one of PA6, PA66, PA56, PA66 / 6T, PA6I / 6T, MXD6, PA1012, PA11, PA12 and PA1212.

[0024] Specifically, the polyamide resin is PA66 and PA6, and the mass ratio of PA66 to PA6 is 2.5-4:1, preferably 2.9-3.2:1, and more preferably 3-3.1:1.

[0025] In the organic phosphorus flame-retardant nylon material, the mass percentage of the polyamide resin is not less than 50%.

[0026] In one embodiment, the organic phosphorus flame retardant is a mixture of aluminum diethyl phosphinate, melamine polyphosphate and zinc borate, or the Exolit OP1400 flame retardant of Clariant; the mass ratio of the aluminum diethyl phosphinate, melamine polyphosphate and zinc borate is aluminum diethyl phosphinate:melamine polyphosphate:zinc borate=(5-7):(0.8-1.2):(0.8-1.2), and more preferably, the mass ratio of the aluminum diethyl phosphinate, melamine polyphosphate and zinc borate is aluminum diethyl phosphinate:melamine polyphosphate:zinc borate=6.5:1:1.

[0027] In one embodiment, the lubricant is at least one of silicone, polyethylene wax and pentaerythritol ester; and / or the antioxidant is at least one of hindered phenolic antioxidant, hindered amine antioxidant, thioester antioxidant and phosphite antioxidant.

[0028] Preferably, the antioxidant is a complex of hindered phenolic antioxidant and phosphite antioxidant; and the mass ratio of the hindered phenolic antioxidant to the phosphite antioxidant is 1:2-2:1.

[0029] In another aspect, the application provides a preparation method of the organic phosphorus flame-retardant nylon material, comprising the following steps:

[0030] The flame-retardant stabilizer, acid absorbent, lubricant and antioxidant are premixed, and then mixed uniformly with the polyamide resin, and the obtained mixture is added to the main feeding system of the extruder for melt mixing, and the organic phosphorus flame retardant and glass fiber are added to the side feeding system of the extruder for mixing, extrusion and granulation to obtain the organic phosphorus flame-retardant nylon material.

[0031] The preparation method of the product has simple operation steps and can realize industrialized scale production.

[0032] Optionally, the length-diameter ratio of the twin-screw extruder is 36-48:1, the screw rotation speed is 300-500 rpm, and the extrusion temperature is 230-270℃.

[0033] In another aspect, the application provides an application of the organic phosphorus flame-retardant nylon material in preparing electronic and electrical appliances and security materials.

[0034] The organic phosphorus flame-retardant nylon material described in the present application has high yellowing resistance effect, mechanical property and flame-retardant property, and can be used to prepare electronic and electrical appliances, security materials, and is especially suitable for preparing new energy connectors.

[0035] Compared with the prior art, the organic phosphorus flame-retardant nylon material has the following beneficial effects: by introducing specific acid absorbents and flame-retardant stabilizers, on the one hand, the flame-retardant stabilizers can play a certain protective role in flame retardation, and on the other hand, the acid absorbents can neutralize part of the acidity in the organic phosphorus flame-retardant nylon material system, and the two work together to significantly improve the yellowing of the material during processing, broaden the processing window of the organic phosphorus flame-retardant nylon material, and solve the problems caused by large parts and long-period injection molding. DETAILED DESCRIPTION

[0036] In order to better illustrate the purpose, technical scheme and advantages of the present application, the present application will be further described below in combination with specific examples and comparative examples, the purpose of which is to understand the content of the present application in detail, rather than to limit the present application. All other examples obtained by those skilled in the art without creative labor fall within the scope of protection of the present application. The experimental reagents and instruments involved in the implementation of the present application are common reagents and instruments unless otherwise specified.

[0037] The raw materials used in the examples and comparative examples are described as follows, but are not limited to these materials:

[0038] Polyamide resin 1: PA66, Invista, PA66 U3600 NC01 SS;

[0039] Polyamide resin 2: PA6, Haiyang Chemical Fiber, HY-2500A;

[0040] Polyamide resin 3: PA66 / 6T, Invista, NPD-652;

[0041] Polyamide resin 4: PA66, Shenma, PA66 EPR24;

[0042] Polyamide resin 5: PA6, Xinhui Meida, PA6 M2400;

[0043] Organic phosphorus flame retardant 1: a compound of aluminum diethyl phosphite, melamine polyphosphate and zinc borate, the mass ratio of aluminum diethyl phosphite, melamine polyphosphate and zinc borate is aluminum diethyl phosphite: melamine polyphosphate: zinc borate = 6.5: 1: 1, wherein the aluminum diethyl phosphite is purchased from Clariant, Exoplit OP1230, and the melamine polyphosphate and zinc borate are commercially available products;

[0044] Organic phosphorus flame retardant 2: Exoplit OP1400, Clariant;

[0045] Glass fiber: Alkali-free chopped glass fiber, Huizhou Giant Stone Group, ECS10-03-568H, chopped length of 3 mm, diameter of 10 μm;

[0046] Flame-retardant stabilizer 1: Ethylene-methacrylic acid-acrylate copolymer, DuPont Dow, Nucrel AN4228C;

[0047] Flame-retardant stabilizer 2: Ionomer of ethylene-methacrylic acid-acrylate terpolymer, DuPont Dow, Surlyn resin 9320;

[0048] Flame-retardant stabilizer 3: Ethylene-methyl acrylate-glycidyl methacrylate copolymer, Arkema, LOTADER AX8900;

[0049] Flame-retardant stabilizer 4: Maleic anhydride grafted ethylene-octene copolymer, DuPont Dow, FUSABOND N493;

[0050] Acid-adsorbing agent 1: Zinc hydroxide, commercially available;

[0051] Acid-adsorbing agent 2: Magnesium hydroxide, commercially available;

[0052] Acid-adsorbing agent 3: Zirconium hydroxide, commercially available;

[0053] Lubricant: Montan ester, TR044W, STRUKTOL;

[0054] Antioxidant: Compound of IRGANOX 1098 and PEP-36, mass ratio of IRGANOX 1098 and PEP-36 being 2:3, IRGANOX 1098 being purchased from BASF, and PEP-36 being purchased from ADEKA.

[0055] Examples and comparative examples

[0056] The components and weight parts of the organic phosphorus flame-retardant nylon material of the examples and comparative examples are shown in Tables 1 and 2, wherein the preparation method of the organic phosphorus flame-retardant nylon material of the examples and comparative examples comprises the following steps:

[0057] The flame-retardant stabilizers, acid-adsorbing agents, lubricants and antioxidants are premixed according to Tables 1 and 2, and then mixed uniformly with the polyamide resin, and the obtained mixture is added to the main feeding system of an extruder for melt mixing, and the organic phosphorus flame retardant and the glass fiber are added to the side feeding system of the extruder, mixed, extruded and granulated to obtain the organic phosphorus flame-retardant nylon material; wherein the length-diameter ratio of the twin-screw extruder is 40:1, the screw rotation speed is 300 rpm, and the extrusion temperature is 230-270°C.

[0058] Table 1

[0059]

[0060]

[0061] Table 2

[0062]

[0063] Performance test:

[0064] (1) The degree of yellowing of the extruded particles: under the same process, standard color plates were injection molded, and the L, a, b values of the color plates were tested using a color difference meter. The degree of yellowing of the material was evaluated by comparing the size of the b value.

[0065] (2) Tensile strength: after the obtained organophosphorus flame-retardant nylon material was dried in a 120°C oven for 4 hours, ISO mechanical samples were injection molded, and the tensile strength of the organophosphorus flame-retardant nylon material was evaluated according to the ISO 527 standard.

[0066] (3) Flexural strength: after the obtained organophosphorus flame-retardant nylon material was dried in a 120°C oven for 4 hours, ISO mechanical samples were injection molded, and the flexural strength of the organophosphorus flame-retardant nylon material was evaluated according to the ISO 178 standard.

[0067] (4) Charpy notched impact strength: after the obtained organophosphorus flame-retardant nylon material was dried in a 120°C oven for 4 hours, ISO mechanical samples were injection molded, and the charpy notched impact strength of the organophosphorus flame-retardant nylon material was evaluated according to the ISO 179 standard.

[0068] (5) UL94 vertical burning @1.6mm: after the obtained organophosphorus flame-retardant nylon material was dried in a 120°C oven for 4 hours, UL flame-retardant samples were injection molded, and the flame-retardant performance of the organophosphorus flame-retardant nylon material was evaluated according to the UL94 standard.

[0069] The test results are shown in Tables 3 and 4.

[0070] Table 3

[0071]

[0072] Table 4

[0073]

[0074]

[0075] From the experimental data in Tables 1-4, it can be seen that the organophosphorus flame-retardant nylon material of the present application improves the yellowing resistance of the product while maintaining the mechanical properties and flame-retardant properties.

[0076] From the comparison of Example 1 and Examples 8-10, it can be seen that the mass ratio of the acid-adsorbing agent and the flame-retardant stabilizer affects the yellowing resistance of the organic phosphine flame-retardant nylon material. When the mass ratio of the acid-adsorbing agent and the flame-retardant stabilizer is (2:1)-(1:2), the yellowing degree of the organic phosphine flame-retardant nylon material is small.

[0077] From the comparison of Example 1 and Examples 13-14, it can be seen that when the acid-adsorbing agent is zinc hydroxide, the yellowing degree of the organic phosphine flame-retardant nylon material is small.

[0078] From the comparison of Example 1 and Comparative Examples 1-3, it can be seen that in the present application, the acid-adsorbing agent and the flame-retardant stabilizer are used in combination, and the two synergistically reduce the yellowing degree of the organic phosphine flame-retardant nylon material.

[0079] From the comparison of Example 1 and Comparative Example 6, it can be seen that when the flame-retardant stabilizer is a maleic anhydride grafted ethylene-octene copolymer, the yellowing degree of the organic phosphine flame-retardant nylon material is significantly increased.

[0080] From the comparison of Example 1 and Comparative Examples 7-10, it can be seen that when the content of the acid-adsorbing agent or the flame-retardant stabilizer is too high or too low, the yellowing degree is increased, and when the content is too high, there is a greater negative impact on other properties (such as mechanical properties or flame-retardant properties).

[0081] Finally, it should be noted that the above examples are used to illustrate the technical solutions of the present application and are not a limitation on the protection scope of the present application. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced by equivalents without departing from the essence and scope of the technical solutions of the present application.

Claims

1. An organophosphorus flame-retardant nylon material, characterized by, The components include the following weight parts: 48-72 parts of polyamide resin, 15-26 parts of organic phosphorus flame retardant, 14-31 parts of glass fiber, 0.08-4.5 parts of flame-retardant stabilizer, 0.08-0.9 parts of acid absorbent; The organic phosphorus flame retardant is a mixture of aluminum diethyl phosphite, melamine polyphosphate and zinc borate, and the mass ratio of the aluminum diethyl phosphite, the melamine polyphosphate and the zinc borate is aluminum diethyl phosphite: melamine polyphosphate: zinc borate = (5-7):(0.8-1.2):(0.8-1.2); The flame-retardant stabilizer is a binary copolymer or a ternary copolymer, the binary copolymer is one of unsaturated hydrocarbon-unsaturated fatty acid copolymer, unsaturated hydrocarbon-unsaturated carboxylic acid ester copolymer, and the binary copolymer is at least one of ethylene-methacrylic acid copolymer, ethylene-methyl acrylate copolymer and ethylene-acrylic acid copolymer; the ternary copolymer is at least one of ethylene-methacrylic acid-acrylate copolymer, ionomer of ethylene-methacrylic acid-acrylate ternary copolymer and ethylene-methyl acrylate-glycidyl methacrylate; and the acid absorbent is a metal hydroxide; The metal hydroxide is at least one of magnesium hydroxide, zinc hydroxide and zirconium hydroxide.

2. The organophosphorous flame retardant nylon material of claim 1, wherein, The mass ratio of the acid absorbent and the flame-retardant stabilizer is 1:2-2:

1.

3. The organophosphorous flame retardant nylon material of claim 1, wherein, The glass fiber is alkali-free short-cut glass fiber.

4. The flame retardant nylon material of claim 1, wherein, The polyamide resin is at least one of PA6, PA66, PA56, PA66 / 6T, PA6I / 6T, MXD6, PA1012, PA11, PA12 and PA1212.

5. The organophosphorous flame retardant nylon material of claim 1, wherein, The organic phosphorus flame-retardant nylon material further includes 0.1-2 parts by weight of lubricant and 0.1-3 parts by weight of antioxidant; The lubricant is at least one of silicone, polyethylene wax and pentaerythritol ester; and the antioxidant is at least one of hindered phenolic antioxidant, hindered amine antioxidant, thioester antioxidant and phosphite antioxidant.

6. The method for preparing an organic phosphine flame-retardant nylon material according to claim 5, wherein: The method includes the following steps: The flame-retardant stabilizer, the acid absorbent, the lubricant and the antioxidant are premixed, and then mixed uniformly with the polyamide resin, and the obtained mixture is added to the main feeding system of an extruder for melt mixing; the organic phosphorus flame retardant and the glass fiber are added to the side feeding system of the extruder, and then mixed, extruded and granulated to obtain the organic phosphorus flame-retardant nylon material.

7. Use of the organic phosphorus flame-retardant nylon material according to any one of claims 1-5 in the preparation of electronic and electrical appliances and security materials.

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