Low-odor flame-retardant polyamide composite material, and preparation method therefor and use thereof

Abstract

Disclosed in the present invention are a low-odor flame-retardant polyamide composite material, and a preparation method therefor and a user thereof. The polyamide composite material comprises the following components in parts by weight: 20-60 parts of a polyamide resin, 13-30 parts of aluminum diethylphosphinate, 4-10 parts of a synergistic flame retardant, 15-40 parts of glass fibers, 1-5 parts of polyethylene glycol, and 0.1-2 parts of a thermal stabilizing aid. The polyamide composite material of the present invention successfully solves the problem of strong odor of flame-retardant polyamide and has high notched impact strength.

Description

A low-odor flame-retardant polyamide composite material and its preparation method and application Technical Field

[0001] The present invention relates to the technical field of polymer materials, and in particular to a low-odor flame-retardant polyamide composite material, a preparation method thereof, and applications thereof. Background Art

[0002] Polyamide, commonly known as nylon, is an important thermoplastic engineering plastic. Due to its many excellent properties such as high strength, good self-lubrication, wear resistance, oil resistance, and easy molding and processing, it is widely used in automobiles, mechanical parts, electronic appliances, home appliances, new energy and other fields. Phosphinate flame-retardant polyamide is commonly used in connectors, low-voltage electrical appliances, energy storage and other industries due to its excellent comprehensive mechanical properties, easy coloring, easy processing, and high CTI. However, phosphinate flame-retardant polyamide has a strong odor, making it difficult to use in the automotive, electronic and electrical fields. Therefore, there is an urgent need for a low-odor and high-impact polyamide composite material to meet the needs of the automotive, electronic and electrical, energy storage, connector and other industries. Summary of the Invention

[0003] In view of the defects in the prior art, the present invention provides a flame-retardant polyamide composite material with low odor and high impact strength, as well as a preparation method and application thereof.

[0004] The present invention provides a low-odor flame-retardant polyamide composite material, which comprises the following components, calculated in parts by weight: 20-60 parts of polyamide resin, such as 20, 25, 30, 40, 45, 55, and 60 parts; 13-30 parts of aluminum diethylphosphinate, such as 13, 15, 18, 20, 25, and 30 parts; 4-10 parts of a synergistic flame retardant, such as 4, 6, 8, and 10 parts; 15-40 parts of glass fiber, such as 15, 20, 25, 30, and 40 parts; 1-5 parts of polyethylene glycol, such as 1, 2, 3, and 5 parts; and 0.1-2 parts of a heat stabilizing agent, such as 0.1, 0.2, 0.5, 1, and 2 parts.

[0005] The mass percentage of the polyamide resin in the composition is 33%-48%.

[0006] Furthermore, the number average molecular weight of the polyethylene glycol is 4000-8000.

[0007] In flame-retardant polyamide composites, the simultaneous addition of polyethylene glycol and thermal stabilizer can significantly improve the odor level of halogen-free flame-retardant nylon products.

[0008] Furthermore, the heat stabilizing agent is any one of a phenolic heat stabilizer, a phosphorus-containing heat stabilizer, an amine heat stabilizer, and a copper-containing heat stabilizer. The above-mentioned phenolic heat stabilizer is a molecule containing a phenol group, such as 1010, but not limited thereto; the above-mentioned phosphorus-containing heat stabilizer is a molecule containing phosphorus element, preferably a phosphorous acid or phosphite antioxidant, such as bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite, 2,2-ethylenebis(4,6-di-tert-butylbenzene)fluorophosphite, tris(2,4-di-tert-butylphenyl)phosphite, more preferably 2,2-ethylenebis(4,6-di-tert-butylbenzene)fluorophosphite; the above-mentioned amine heat stabilizer is a molecule containing amine, such as HALS-944 and Nyrostab S-EED, but not limited thereto; the above-mentioned copper-containing heat stabilizer refers to a stabilizer containing a mixture of copper salt and alkali metal halide and / or alkaline earth metal halide.

[0009] Furthermore, the heat stabilizing agent is a phosphorus-containing heat stabilizer.

[0010] Furthermore, the polyamide resin is any one of the condensation products of one or more dicarboxylic acids and one or more diamines, the condensation products of one or more aminocarboxylic acids, and the ring-opening polymerization products of one or more cyclic lactams, preferably PA66 or PA610.

[0011] Furthermore, the relative viscosity of the polyamide resin is 2.0-3.4. The relative viscosity of a 0.01 g / mL concentrated sulfuric acid solution of the polyamide resin tested at 25° C. is 2.0-3.4. The detection method of the relative viscosity is as follows: weigh 0.5 g of the polyamide resin, transfer it to a 50 mL volumetric flask, add about 40 mL of 96% by mass concentrated sulfuric acid, oscillate ultrasonically until the polyamide resin is completely dissolved, cool the solution to 25° C., dilute to the scale with concentrated sulfuric acid, and mix evenly. Test the flow time of a 0.01 g / mL polyamide resin solution through an Ubbelohde viscometer at 25° C., record it as t1, and use the same viscometer to test the flow time of the solvent concentrated sulfuric acid, record it as t2, and t1 / t2 is the relative viscosity.

[0012] Furthermore, the synergistic flame retardant is one or more of melamine polyphosphate, melamine aluminum polyphosphate, melamine magnesium polyphosphate, melamine cyanurate, melamine zinc polyphosphate, and zinc borate, preferably melamine polyphosphate and zinc borate.

[0013] The flame retardant of the present invention is a compound of diethyl aluminum hypophosphite and the above synergistic flame retardant, preferably a compound of diethyl aluminum hypophosphite and melamine polyphosphate or melamine polyphosphate aluminum, more preferably a compound of diethyl aluminum hypophosphite and melamine polyphosphate.

[0014] Furthermore, the glass fiber is at least one of E glass fiber, A glass fiber, S glass fiber, D glass fiber, C glass fiber, and quartz glass fiber, preferably alkali-free glass fiber.

[0015] Furthermore, the polyamide composite material further includes a lubricant, which is at least one of hydrocarbons, esters, alcohols, fatty acids, fatty acid amides, and metal soaps; preferably an ester lubricant, such as fatty acid esters, polyol esters, and polyethylene glycol esters. The lubricant is present in an amount of 0-1 parts by weight.

[0016] The composition of the present invention may further contain color powder without impairing the effects of the present invention, wherein the color powder is in an amount of 0-2 parts by weight.

[0017] The present invention also provides a method for preparing the polyamide composite material, comprising the steps of mixing the components, extruding and granulating;

[0018] The specific steps are as follows: weighing each component by weight, mixing all components except glass fiber in a high-speed mixer for 3-10 minutes, then adding the components to the main feed hopper of a twin-screw extruder, adding glass fiber from the side feed hopper of the sixth section of the screw barrel, fully plasticizing and melting, extruding, drawing into strands, cooling, and pelletizing to produce a polyamide composite material. The twin-screw extruder has a screw speed of 300-800 rpm, an aspect ratio of 36:1-48:1, a screw barrel temperature of 160°C-250°C at each section, and a die head temperature of 230°C-260°C.

[0019] The present invention also provides application of the polyamide composite material in the preparation of automobile and electronic and electrical appliance materials.

[0020] In summary, compared with the prior art, the present invention achieves the following technical effects:

[0021] (1) The polyamide composite material of the present invention successfully solves the problem of severe odor of flame retardant polyamide.

[0022] (2) The polyamide composite material of the present invention has high notched impact strength. DETAILED DESCRIPTION

[0023] In order to help those skilled in the art better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention are clearly and completely described below. Obviously, the embodiments described 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 those skilled in the art without making any creative efforts should fall within the scope of protection of the present invention.

[0024] Example

[0025] The present invention is further described below with reference to specific examples and comparative examples. The following specific examples are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the following examples, and are particularly not limited to the types of the various component raw materials used in the following specific examples.

[0026] 1. The sources of raw materials for the embodiments and comparative examples are as follows:

[0027] Polyamide resin #1: Nylon 66, brand PA66EPR24, relative viscosity 2.4, Shenma Group;

[0028] Polyamide resin #2: PA610, brand PA610RV26, relative viscosity 2.6, Shanghai Yinggu Chemical Co., Ltd.

[0029] Aluminum diethylphosphinate: brand Exolit OP 1230, Clariant;

[0030] MCA flame retardant: the brand is nitrogen-based flame retardant lubricant MCA, purchased from Sichuan Fine Chemical Research and Design Institute;

[0031] Synergistic flame retardant #1: melamine polyphosphate, brand Budit 3141, Bode;

[0032] Synergistic flame retardant #2: melamine cyanurate, brand name melamine cyanurate MCA, Shouguang Weidong Chemical;

[0033] Glass fiber: E glass fiber, brand ECS10-03-568H, China Jushi Co., Ltd.

[0034] Polyethylene glycol #1: molecular weight 4000, brand PEG-4000, Guangzhou Jinchangsheng Technology Co., Ltd.

[0035] Polyethylene glycol #2: molecular weight 8000, brand PEG-8000, Guangzhou Fengtian Chemical Co., Ltd.

[0036] Polyethylene glycol #3: molecular weight 10,000, brand PEG-10000, obtained from Guangzhou Rongda Chemical Company;

[0037] Thermal Stabilizer #1: Amine antioxidant, brand HALS-944, Liansheng Group;

[0038] Thermal Stabilizer #2: Phosphorus-containing thermal stabilizer, 2,2-ethylenebis(4,6-di-tert-butylbenzene)fluorophosphite;

[0039] Thermal Stabilizer #3: Phosphorus-containing thermal stabilizer, tris(2,4-di-tert-butylphenyl) phosphite;

[0040] Thermal stabilizer #4: phosphorus-containing thermal stabilizer, bis(2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, brand PEP-36, Aidico (China) Investment Co., Ltd.

[0041] Thermal Stabilizer #5: Copper salt antioxidant, brand 8:1:1 Ki / CuI / Zn Stearate Pellets, AJAY;

[0042] Heat stabilizer #6: phenolic antioxidant, brand 1010, BASF;

[0043] Lubricant: TR044W, ester lubricant. Parallel experiments used the same substance.

[0044] The preparation method of the polyamide composite material of the embodiment of the present invention and the comparative example comprises the following steps:

[0045] Each component, excluding the glass fiber, is weighed by weight and mixed in a high-speed mixer for 3-10 minutes. The mixture is then added to the main feed hopper of a twin-screw extruder. The glass fiber is then added through the side feed hopper of the sixth section of the barrel. After being fully plasticized and melted, the extruder is extruded, stretched into strands, cooled, and pelletized to produce a polyamide composite material. The twin-screw extruder has a screw speed of 300-800 rpm, an aspect ratio of 36:1-48:1, a barrel temperature of 160°C-250°C at each section, and a die head temperature of 230°C-260°C.

[0046] 2. Various performance test methods

[0047] (1) Odor test method:

[0048] The test standard is VW50180-2015, with 5 odor assessors.

[0049] Odor evaluation was performed for all variants according to a rating scale of 1-6, with intermediate scale values ​​also possible.

[0050] Evaluation scale:

[0051] Score: 1: Can't feel

[0052] Score: 2: Perceptible, not disturbing

[0053] Score: 3: noticeable but not disturbing

[0054] Score 4 Annoying

[0055] Score: 5 Strongly Disliked

[0056] Score 6: Intolerable

[0057] The odor characteristics are reported as arithmetic mean values ​​for the individual scores, depending on the test method and the variant used, with the mean values ​​being divided into half-value classes when rounded.

[0058] (2) Notched impact strength test method

[0059] In accordance with the test standard ISO 180-2019, ISO standard test specimens are used.

[0060] Table 1 Example technical solutions and effects (units are parts by weight)

[0061] Table 2 Comparative Examples Technical Scheme and Effects (Units are parts by weight)

[0062] Comparative Examples 1-5 all used a single variable similar to Example 2. Comparative Examples 1-2 did not include polyethylene glycol or a heat stabilizer. While the odor level was lower than that of Example 2, it was found that polyethylene glycol and the heat stabilizer synergized in reducing the odor level. Comparative Example 3 contained excessive polyethylene glycol, Comparative Example 4 contained excessive heat stabilizer, and Comparative Example 5 did not include diethylaluminum hypophosphite as the flame retardant. Consequently, the polyethylene glycol and the heat stabilizer failed to synergize effectively in reducing odor in this system. Consequently, none of the above comparative examples achieved both low odor levels and high notched impact strength.

[0063] Based on the test data of odor level and notched impact strength in Table 1 and Table 2, the polyamide composite materials prepared by Examples 1-13 have high mechanical properties, and the notched impact strength can reach 7.3 kJ / m 2 , and its odor level can reach level 3 under the premise that the notched impact strength can meet the conditions. Compared with the control ratio, it has obvious advantages and can effectively meet the high standards of customers and the market.

[0064] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A low-odor flame-retardant polyamide composite material, characterized in that: In parts by weight, it includes the following components:

2. The polyamide composite material according to claim 1, characterized in that: The number average molecular weight of the polyethylene glycol is 4000-8000.

3. The polyamide composite material according to claim 1, characterized in that: The heat stabilizing agent is any one of a phenolic heat stabilizer, a phosphorus-containing heat stabilizer, an amine heat stabilizer, and a copper-containing heat stabilizer.

4. The polyamide composite material according to claim 1 or 3, characterized in that: The heat stabilizing agent is a phosphorus-containing heat stabilizer.

5. The polyamide composite material according to claim 1, characterized in that: The polyamide resin is any one of the condensation products of one or more dicarboxylic acids and one or more diamines, the condensation products of one or more aminocarboxylic acids, and the ring-opening polymerization products of one or more cyclic lactams, preferably PA66 or PA610.

6. The polyamide composite material according to claim 1 or 5, characterized in that: The relative viscosity of the polyamide resin is 2.0-3.

4.

7. The polyamide composite material according to claim 1, characterized in that: The synergistic flame retardant is one or more of melamine polyphosphate, melamine aluminum polyphosphate, melamine magnesium polyphosphate, melamine cyanurate, melamine zinc polyphosphate, and zinc borate.

8. The polyamide composite material according to claim 1, characterized in that: The glass fiber is at least one of E glass fiber, A glass fiber, S glass fiber, D glass fiber, C glass fiber, and quartz glass fiber.

9. The method for preparing the polyamide composite material according to any one of claims 1 to 8, characterized in that: The process comprises the steps of mixing, extruding and granulating the components.

10. Use of the polyamide composite material according to any one of claims 1 to 8 in the preparation of automobile and electronic and electrical materials.

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