Halogen-free flame-retardant long carbon chain nylon composite and preparation method and application thereof

Abstract

The application discloses a halogen-free flame-retardant long carbon chain nylon compound and a preparation method and application thereof, the halogen-free flame-retardant long carbon chain nylon compound comprises the following components in parts by weight: long carbon chain aliphatic nylon 48-58 parts; aromatic crystalline nylon 6-12 parts; non-crystalline nylon 3-6 parts; glass fiber 20-30 parts; hypophosphite 8-12 parts; melamine derivative 1-2 parts; flame-retardant synergist 0.5-2 parts; and the flame-retardant synergist is stannate. The halogen-free flame-retardant long carbon chain nylon compound has good flame-retardant performance and mechanical properties, and can meet the requirements of modern electronic and electrical industries.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of high polymer materials, in particular to a halogen-free flame-retardant long carbon chain nylon compound, a preparation method and application thereof. BACKGROUND

[0002] Long carbon chain nylon refers to nylon with the number of methylene groups between adjacent amide bonds in the main chain of macromolecules being greater than or equal to 10, such as PA610, PA612 and PA1010, etc. Compared with conventional PA6 and PA66, long carbon chain nylon has the advantages of small density, low water absorption, good dimensional stability, excellent chemical resistance and outstanding low temperature resistance, and is widely used in various parts of automobiles, such as oil delivery pipes, copper braid rubber coating, wiper and sound reduction gears, etc.

[0003] Long carbon chain nylon has low moisture absorption, excellent electrical properties and electrochemical corrosion resistance, and has great potential application prospects in the electronic and electrical industries. However, the electronic and electrical industries have strict requirements for the flame retardant properties of materials. Compared with PA6 and PA66 materials, long carbon chain nylon has low carbon efficiency, and it is difficult for a halogen-free flame retardant system to achieve UL94 V-0. There is prior art that introduces an appropriate amount of long carbon chain nylon into phosphine-based flame-retardant nylon to prepare a high-breakdown voltage-resistant flame-retardant nylon material. However, it is essentially a phosphine-based flame-retardant PA66 material, and long carbon chain nylon is only used as an additive to reduce water absorption. In addition, due to the introduction of long carbon chain nylon resin, the amount of phosphorus-based flame retardant needs to be added to 25-35 parts to achieve V-0, which not only reduces the injection stability of the material, but also causes the risk of precipitation during long-term storage. The electronic and electrical industries are showing a trend of miniaturization and thinning, and 1.6mm UL94 V-0 cannot meet the development requirements of the electronic and electrical industries. SUMMARY

[0004] In order to overcome the defects of the prior art, the present application provides a halogen-free flame-retardant long carbon chain nylon compound with excellent flame retardant properties and mechanical properties, a preparation method and application thereof, and the specific technical solutions are as follows:

[0005] A halogen-free flame-retardant long carbon chain nylon compound, by weight, comprising the following components: 48-58 parts of long carbon chain aliphatic nylon, such as 48, 50, 52, 54, 56, 58 parts; 6-12 parts of aromatic crystalline nylon, such as 6, 8, 10, 11, 12 parts; 3-6 parts of non-crystalline nylon, such as 3, 4, 5, 6 parts; 20-30 parts of glass fiber, such as 20, 22, 24, 26, 28, 30 parts; 8-12 parts of hypophosphite, such as 8, 10, 11, 12 parts; 1-2 parts of melamine derivative, such as 1, 1.5, 2 parts; 0.5-2 parts of flame retardant synergist, such as 0.5, 1, 1.5, 2 parts; and the flame retardant synergist is stannate.

[0006] The minimum mass percentage of the long carbon chain aliphatic nylon in the halogen-free flame-retardant long carbon chain nylon composite is 40%.

[0007] Further, the long carbon chain aliphatic nylon is one or more of PA610, PA612, PA12, PA1010 or PA1012.

[0008] Further, the aromatic crystalline nylon is one or more of PA66 / 6T, PA MXD6 or PA MXD10.

[0009] Further, the non-crystalline nylon is PA6T / 6I or TM156, preferably PA6T / 6I.

[0010] Further, the mass ratio of the long carbon chain aliphatic nylon and the aromatic crystalline nylon is (3-10):1, such as 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, 10:1, preferably (3-5):1, such as 3:1, 4:1, 5:1.

[0011] Further, the weight percentage of the non-crystalline nylon in the total weight percentage of the long carbon chain aliphatic nylon and the aromatic crystalline nylon is 5-10wt%.

[0012] Further, the stannate is one or more of magnesium stannate, zinc stannate and calcium stannate, preferably zinc stannate. The stannate is introduced as a flame-retardant synergist to promote the efficient carbonization of the halogen-free flame retardant during combustion, to some extent to compensate for the poor carbonization of the long carbon chain aliphatic nylon.

[0013] Further, the hypophosphite is one or more of aluminum hypophosphite, diethyl aluminum hypophosphite or diisopropyl aluminum hypophosphite, preferably diethyl aluminum hypophosphite.

[0014] Further, the glass fiber is one or more of E glass fiber, H glass fiber, S glass fiber, D glass fiber or C glass fiber, preferably E glass fiber.

[0015] Further, the melamine derivative is melamine polyphosphate.

[0016] The application also provides a preparation method of the above-mentioned halogen-free flame-retardant long carbon chain nylon composite, comprising the following steps:

[0017] S1: according to the ratio, the components are weighed and pre-mixed to obtain a pre-mixture;

[0018] S2: the pre-mixture of step S1 is put into an extruder for melt blending and extrusion granulation to obtain the halogen-free flame-retardant long carbon chain nylon composite.

[0019] Further, the extruder is a double screw extruder, the length-diameter ratio of the screw of the double screw extruder is (40-48):1, the barrel temperature of the double screw extruder is 160-260 DEG C, and the rotation speed of the screw of the double screw extruder is 300-600 r / min.

[0020] The application further provides application of the halogen-free flame-retardant long carbon chain nylon compound in preparation of plastic parts of electronic appliances, such as preparation of a television shell.

[0021] Compared with the prior art, the application has the beneficial effects that:

[0022] The long carbon chain nylon compound prepared by compounding three different nylons, i.e., long carbon chain aliphatic nylon, aromatic crystalline nylon and non-crystalline nylon, and selecting specific flame-retardant synergists, has excellent flame-retardant performance without adding a large amount of glass fiber and flame retardant, the flame-retardant grade can reach UL94 V-0, the flame-retardant thickness can reach 0.8 mm, and the requirements of miniaturization and thin-wall electronic appliances are met. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the application will be described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the application.

[0024] <Preparation of examples and comparative examples>

[0025] The raw materials used in the examples and comparative examples of the application are all commercially available, but are not limited to these materials.

[0026] Long carbon chain aliphatic nylon:

[0027] PA610, brand PA610 F120, Shandong Guangyin New Material Co., Ltd.;

[0028] PA612, brand PA612 A120, Shandong Guangyin New Material Co., Ltd.;

[0029] PA1010, brand PA1010 G150, Shandong Guangyin New Material Co., Ltd.;

[0030] PA1012, brand Hiprolon 400NNLM, Arkema Co., Ltd., France;

[0031] Aromatic crystalline nylon:

[0032] PA66 / 6T, brand NPD-652, Ineos;

[0033] PA MXD6, grade MXD6 AP 250, Shanghai Yinggu Co., Ltd.;

[0034] Non-crystalline nylon-1, grade TM156, Changyu Group;

[0035] Non-crystalline nylon-2, grade TI1207, Shandong Guangyin New Material Co., Ltd.;

[0036] Glass fiber, grade ECS10-3.0-568H, China Jushi Co., Ltd.;

[0037] Aluminum diethyl phosphinate, grade OP1230, Clariant Co., Ltd.;

[0038] Melamine polyphosphate, grade: BUDIT 3141, purchased from Budenheim Iberica Co., Ltd. in Germany;

[0039] Zinc stannate, grade Flamtard S, Shanghai Xima Chemical Co., Ltd.;

[0040] Magnesium stannate, grade Magnesium stannate, Henan Jiasun Chemical Product Co., Ltd.;

[0041] Zinc borate, grade ZB-503, Anhui Yishitong Material Technology Co., Ltd.

[0042] The preparation method of the embodiments and comparative examples of the present application is as follows:

[0043] S1: according to the ratio of Table 1 and Table 3, each component was weighed and premixed to obtain a premix;

[0044] S2: the premix of step S1 was put into a twin-screw extruder, and melt blending and extrusion granulation were carried out to obtain a halogen-free flame-retardant long carbon chain nylon composite.

[0045] The screw length-diameter ratio of the twin-screw extruder was 40:1, the barrel temperature of the twin-screw extruder was 250℃, and the screw rotation speed of the twin-screw extruder was 400r / min.

[0046] In this specification, “parts” means “parts by weight” unless otherwise specified.

[0047] <Testing standards>

[0048] The performance testing standards of the embodiments and comparative examples of the present application are as follows:

[0049] Flame Retardant Performance: The flame retardant performance of the sample was tested according to the relevant standard of UL 94-2015, the sample thickness was 0.8mm, the flame retardant level was divided into V-0, V-1, V-2 and no level (NR); the flame retardant performance was of great significance to electrical safety, and the UL94 flame retardant level needed to reach V-0 to meet the application requirements;

[0050] Tensile Strength: tested according to ISO 527-2012;

[0051] Notched Izod Impact Strength: tested according to ISO 180-2000.

[0052] Table 1. Formulation of Examples (parts by weight)

[0053]

[0054] Table 2. Test results of examples

[0055]

[0056]

[0057] Table 3. Formulation of Comparative Examples (parts by weight)

[0058]

[0059] Table 4. Test results of comparative examples

[0060]

[0061] It can be seen from examples 1-10 that the flame retardant performance of the halogen-free flame-retardant long carbon chain nylon composite prepared by the application can reach V-0 level, the tensile strength is greater than 118MPa, and the notched Izod impact strength is greater than 11.4kJ / m 2 Therefore, the halogen-free flame-retardant long carbon chain nylon composite provided by the application has excellent flame retardant performance and mechanical properties.

[0062] It can be seen from example 3 and comparative example 2 that comparative example 2 does not add aromatic crystalline nylon, resulting in unqualified flame retardant performance, and the tensile strength and notched Izod impact strength are also reduced.

[0063] It can be seen from examples 3, comparative example 1 and comparative example 9 that without introducing non-crystalline nylon, the mechanical properties and flame retardant properties of the halogen-free flame-retardant long carbon chain nylon composite are poor; but if the content of non-crystalline nylon is too high, the mechanical properties and flame retardant properties of the halogen-free flame-retardant long carbon chain nylon composite are obviously decreased.

[0064] It can be seen from Example 3, Comparative Example 3 and Comparative Example 4 that the halogen-free flame-retardant long carbon chain nylon composite does not reach V-0 without melamine polyphosphate or without stannate. The main reason is that melamine polyphosphate can act together with aluminum hypophosphite to coordinate and promote the carbonization of the long carbon chain nylon composite, and stannate can act as a catalyst to improve the flame-retardant efficiency of aluminum hypophosphite and melamine polyphosphate.

[0065] It can be seen from Example 3, Comparative Example 5 and Comparative Example 6 that the halogen-free flame-retardant long carbon chain nylon composite does not reach V-0 when the content of hypophosphite is too low, and the mechanical properties of the halogen-free flame-retardant long carbon chain nylon composite are deteriorated when the content of hypophosphite is too high.

[0066] It can be seen from Example 3, Comparative Example 7 and Comparative Example 8 that the halogen-free flame-retardant long carbon chain nylon composite does not reach V-0 when the content of aromatic crystalline nylon is too low, and the notched impact strength of the halogen-free flame-retardant long carbon chain nylon composite is greatly deteriorated when the content of aromatic crystalline nylon is too high.

[0067] It can be seen from Example 3 and Comparative Example 10 that, compared with the conventional flame-retardant synergist zinc borate, stannate has a high flame-retardant synergistic effect in the halogen-free flame-retardant long carbon chain nylon composite system, and has a smaller deterioration on the mechanical properties of the long carbon chain nylon.

[0068] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A halogen-free flame-retardant long carbon chain nylon compound, characterized by, by weight, comprising: long carbon chain aliphatic nylon 48-58 parts; aromatic crystalline nylon 6-12 parts; non-crystalline nylon 3-6 parts; glass fiber 20-30 parts; hypophosphite 8-12 parts; melamine derivative 1-2 parts; flame retardant synergist 0.5-2 parts; the flame retardant synergist is stannate; the long carbon chain aliphatic nylon is one or more of PA610, PA612, PA12, PA1010 or PA1012; the aromatic crystalline nylon is one or more of PA66 / 6T, PA MXD6 or PA MXD10; the non-crystalline nylon is PA6T / 6I or TM156; the hypophosphite is one or more of aluminum diethyl hypophosphite or aluminum diisopropyl hypophosphite; the melamine derivative is melamine polyphosphate.

2. The halogen-free flame-retardant long carbon chain nylon compound according to claim 1, characterized by, The mass ratio of the long carbon chain aliphatic nylon and the aromatic crystalline nylon is (4-5):

1.

3. The halogen-free flame retardant long carbon chain nylon compound according to claim 1, characterized by, The weight parts of the non-crystalline nylon account for 5-10wt% of the total weight parts of the long carbon chain aliphatic nylon and the aromatic crystalline nylon.

4. The halogen-free flame retardant long carbon chain nylon compound according to claim 1, wherein, The flame retardant synergist is zinc stannate.

5. A process for preparing a halogen-free flame-retardant long carbon chain nylon compound according to any one of claims 1 to 4, characterized by, comprising the following steps: S1: weighing each component according to the ratio, pre-mixing to obtain a premix; S2: putting the premix of step S1 into an extruder, melt blending and extruding to obtain the halogen-free flame-retardant long carbon chain nylon compound.

6. Use of the halogen-free flame-retardant long carbon chain nylon compound according to any one of claims 1-4 in the preparation of plastic parts of electronic appliances.

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