Flame-retardant plastic protective shell of lithium ion battery and preparation method of flame-retardant plastic protective shell

Abstract

The invention discloses a flame-retardant plastic protective shell of a lithium ion battery and a preparation method of the flame-retardant plastic protective shell. The invention belongs to the technical field of plastic protective shells. The flame-retardant plastic protective shell is prepared from components in parts by weight as follows: 20-30 parts of polypropylene resin, 15-30 parts of a flame retardant, 1-3 parts of a coupling agent, 20-26 parts of magnesium oxide, 1-5 parts of a flexibilizer, 3-5 parts of a dispersing agent and 2-6 parts of an antioxidant. The performance of the polypropylene resin is improved through the flame retardant, the matrix of the flame retardant is magnesium hydroxide, uniform dispersion of flame retardant components in the matrix can be achieved, and multi-effect flame retardance is achieved; the flame retardant is non-toxic, harmless, efficient and safe, and polypropylene is endowed with uniform, lasting, non-toxic, harmless, efficient and safe flame retardant performance by the flame retardant.

Description

Technical Field

[0001] The invention belongs to the technical field of plastic protective shells, and specifically refers to a flame-retardant plastic protective shell for a lithium-ion battery and a preparation method thereof. Background Art

[0002] At present, plastic products are increasingly widely used in many fields due to their unique good electrical resistance and high-frequency insulation performance that is not affected by humidity. However, since plastic itself is not flame retardant, when used in electronic appliances, construction, aviation and automobile industries, it is flammable and can cause fires. At present, with the advancement of technology, the ubiquitous new products and new things have brought convenient and fast services to people's lives and work, and people's lives have undergone earth-shaking changes. In order to eliminate fire hazards, while enjoying a comfortable and fast life, "high-quality and safe life" will gradually become an indispensable factor in life. In such a fast-paced era, flame-retardant plastic materials have become the darling of the market. This material has excellent flame retardancy, low density, low cost, good comprehensive performance and other superior characteristics, and is suitable for wall switches, sockets, pipes, molded case circuit breakers, motor components, plates and other fields. In recent years, many manufacturers at home and abroad have begun to research and develop flame-retardant plastics, but the flame retardants currently added are mostly halogen flame retardants, which will produce toxic substances such as hydrogen halides during long-term use, especially during combustion, which will cause great harm to people's health and the environment.

[0003] High molecular organic plastics have the characteristics of insulation, light weight, corrosion resistance, good toughness, and easy processing, but their flame retardancy is not ideal. In order to utilize their advantageous properties as flame retardant materials, their flame retardancy must be improved. The flame retardant plastics currently used include halogen / antimony flame retardant polypropylene and halogen-free flame retardant polypropylene materials. The former type of flame retardant polypropylene produces a large amount of corrosive toxic gases and smoke during thermal cracking and combustion, which is prone to secondary disasters. Therefore, according to the market application development trend of flame retardant polymer materials, it is advocated to use halogen-free flame retardant polypropylene materials, especially in the electronic and electrical appliances and automotive parts industries. In the prior art, there are polypropylene plastics using environmentally friendly flame retardant components, such as the invention patent with patent application publication number CN104059278A, which discloses a hydrolysis-resistant, non-migrating halogen-free flame retardant polyolefin composition and its preparation method. The flame retardant used in this scheme is composed of piperazine pyrophosphate and melamine cyanurate. The flame retardant system disclosed in this technical solution can effectively improve the flame retardant properties of polypropylene materials, but the flame retardant substance has a strong polarity, low compatibility with the polypropylene matrix, and an interface effect, making it difficult to achieve uniform dispersion in the polypropylene matrix. Summary of the invention

[0004] The purpose of the present invention is to provide a flame-retardant plastic protective shell for a lithium-ion battery and a preparation method thereof. The present invention improves the performance of a polypropylene resin by using a flame retardant. The matrix of the flame retardant is magnesium hydroxide, which can achieve uniform dispersion of flame retardant components in the matrix and achieve multi-effect flame retardancy. The present invention is non-toxic, harmless, efficient and safe, and the flame retardant imparts uniform, long-lasting, non-toxic, harmless, efficient and safe flame retardant properties to polypropylene.

[0005] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present invention is as follows: a flame-retardant plastic protective shell for a lithium-ion battery and a preparation method thereof, wherein the flame-retardant plastic protective shell comprises the following components in parts by weight: 10-50 parts of polypropylene resin, 10-70 parts of flame retardant, 1-5 parts of coupling agent, 10-30 parts of magnesium oxide, 0.2-10 parts of toughening agent, 1-8 parts of dispersant, and 0.5-20 parts of antioxidant.

[0006] Preferably, the flame-retardant plastic protective shell comprises the following components in parts by weight: 15-45 parts of polypropylene resin, 15-60 parts of flame retardant, 1-4 parts of coupling agent, 15-30 parts of magnesium oxide, 0.5-10 parts of toughening agent, 2-7 parts of dispersant, and 1-18 parts of antioxidant.

[0007] Preferably, the flame-retardant plastic protective shell comprises the following components in parts by weight: 20-30 parts of polypropylene resin, 15-30 parts of flame retardant, 1-3 parts of coupling agent, 20-26 parts of magnesium oxide, 1-5 parts of toughening agent, 3-5 parts of dispersant, and 2-6 parts of antioxidant.

[0008] Furthermore, the flame retardant is prepared from 2-aminoethanesulfonic acid, tetrahydrofuran, sodium carbonate and dichloromethane.

[0009] Furthermore, the coupling agent is one or more of triethoxysilane and polyethylene glycol trimethoxysilyl propyl ether.

[0010] Furthermore, the toughening agent is one or more of ethylene-octene copolymer and ethylene propylene diene monomer rubber.

[0011] Furthermore, the dispersant is one or more of polyethylene wax, polypropylene wax and liquid paraffin.

[0012] Furthermore, the antioxidant is one or more of antioxidant 1010, antioxidant 168, avocado oil and tert-butylhydroquinone.

[0013] The present invention also provides a method for preparing a flame-retardant plastic protective shell of a lithium-ion battery, the preparation method comprising the following steps:

[0014] (1) Put polypropylene resin, flame retardant, coupling agent, magnesium oxide, toughening agent, dispersant and antioxidant into a high-speed mixer according to proportion and mix until the material temperature rises and the discharged material is cooled;

[0015] (2) The cooled mixed material is fed into a twin-screw extruder for melt extrusion, injected into a shell mold, cooled and dried in a water tank, and the flame-retardant plastic protective shell is obtained.

[0016] Furthermore, the temperature in step (1) is 90-100°C.

[0017] The beneficial effects achieved by the present invention using the above structure are as follows: (1) The present invention improves the performance of polypropylene resin by using a flame retardant, and the matrix of the flame retardant is magnesium hydroxide, which can achieve uniform dispersion of the flame retardant components in the matrix and achieve multi-effect flame retardancy; (2) The present invention is non-toxic, harmless, efficient and safe, so that the flame retardant gives polypropylene uniform, long-lasting, non-toxic, harmless, efficient and safe flame retardant properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Burning rate of flame retardant plastic protective casing.

[0019] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0021] Unless otherwise defined, all professional and scientific terms used herein have the same meanings as those familiar to those skilled in the art. In addition, any methods and materials similar or equivalent to those described herein may be applied to the present invention. The preferred implementation methods and materials described herein are for demonstration purposes only and are not intended to limit the content of this application.

[0022] The experimental methods in the following examples are conventional methods unless otherwise specified; the experimental materials and test strains used in the following examples are purchased from commercial channels unless otherwise specified.

[0023] Example 1

[0024] A flame-retardant plastic protective shell for lithium-ion battery and a preparation method thereof

[0025] The flame-retardant plastic protective shell comprises the following components in parts by weight: 20 parts of polypropylene resin, 15 parts of flame retardant, 1 part of coupling agent, 20 parts of magnesium oxide, 1 part of toughening agent, 3 parts of dispersant and 2 parts of antioxidant.

[0026] The flame retardant is prepared from 2-aminoethanesulfonic acid, tetrahydrofuran, sodium carbonate and dichloromethane.

[0027] Wherein, the coupling agent is triethoxysilane; and the toughening agent is ethylene-octene copolymer.

[0028] Wherein, the dispersant is polyethylene wax; and the antioxidant is avocado oil.

[0029] The present invention also provides a method for preparing a flame-retardant plastic protective shell of a lithium-ion battery, the preparation method comprising the following steps:

[0030] (1) Put polypropylene resin, flame retardant, coupling agent, magnesium oxide, toughening agent, dispersant and antioxidant into a high-speed mixer according to proportion and mix until the material temperature rises and the discharged material is cooled;

[0031] (2) The cooled mixed material is fed into a twin-screw extruder for melt extrusion, injected into a shell mold, cooled and dried in a water tank, and the flame-retardant plastic protective shell is obtained.

[0032] Wherein, the temperature in step (1) is 90-100°C.

[0033] Example 2

[0034] A flame-retardant plastic protective shell for lithium-ion battery and a preparation method thereof

[0035] The flame-retardant plastic protective shell comprises the following components in parts by weight: 25 parts of polypropylene resin, 22 parts of flame retardant, 2 parts of coupling agent, 26 parts of magnesium oxide, 3 parts of toughening agent, 5 parts of dispersant and 6 parts of antioxidant.

[0036] The flame retardant is prepared from 2-aminoethanesulfonic acid, tetrahydrofuran, sodium carbonate and dichloromethane.

[0037] Wherein, the coupling agent is triethoxysilane; and the toughening agent is ethylene-octene copolymer.

[0038] Wherein, the dispersant is polyethylene wax; and the antioxidant is avocado oil.

[0039] The present invention also provides a method for preparing a flame-retardant plastic protective shell for a lithium-ion battery, and the preparation method is implemented with reference to Example 1.

[0040] Example 3

[0041] A flame-retardant plastic protective shell for lithium-ion battery and a preparation method thereof

[0042] The flame retardant plastic protective shell comprises the following components in parts by weight: 30 parts of polypropylene resin, 28 parts of flame retardant, 3 parts of coupling agent, 22 parts of magnesium oxide, 5 parts of toughening agent, 4 parts of dispersant and 4 parts of antioxidant.

[0043] The flame retardant is prepared from 2-aminoethanesulfonic acid, tetrahydrofuran, sodium carbonate and dichloromethane.

[0044] Wherein, the coupling agent is triethoxysilane; and the toughening agent is ethylene-octene copolymer.

[0045] Wherein, the dispersant is polyethylene wax; and the antioxidant is avocado oil.

[0046] The present invention also provides a method for preparing a flame-retardant plastic protective shell for a lithium-ion battery, and the preparation method is implemented with reference to Example 1.

[0047] Experimental Example 1

[0048] The flame retardant plastic protective casings of lithium ion batteries prepared in Example 1, Example 2 and Example 3 were tested for flame retardant properties, wherein the flame retardant properties were tested using a BG-5210 vertical combustion apparatus produced by Suzhou Benco Instrument Co., Ltd. in accordance with ASTM D3810-10.

[0049] Result analysis: Figure 1 As shown, Examples 1-3 all have relatively low combustion rates, and the board prepared in Example 3 has the lowest combustion rate.

[0050] 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.

[0051] The present invention and its embodiments are described above, and such description is not restrictive. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. In short, if ordinary technicians in the field are inspired by it, without departing from the purpose of the invention, they can design a structure and embodiment similar to the technical solution without creativity, which should belong to the protection scope of the present invention.

Claims

1. A flame-retardant plastic protective shell for a lithium-ion battery, characterized in that: The flame retardant plastic protective shell comprises the following components in parts by weight: 10-50 parts of polypropylene resin, 10-70 parts of flame retardant, 1-5 parts of coupling agent, 10-30 parts of magnesium oxide, 0.2-10 parts of toughening agent, 1-8 parts of dispersant, and 0.5-20 parts of antioxidant.

2. The flame-retardant plastic protective shell for lithium-ion batteries according to claim 1, characterized in that: The flame-retardant plastic protective shell comprises the following components in parts by weight: 15-45 parts of polypropylene resin, 15-60 parts of flame retardant, 1-4 parts of coupling agent, 15-30 parts of magnesium oxide, 0.5-10 parts of toughening agent, 2-7 parts of dispersant and 1-18 parts of antioxidant.

3. A flame-retardant plastic protective shell for lithium-ion batteries according to claim 2, characterized in that: The flame-retardant plastic protective shell comprises the following components in parts by weight: 20-30 parts of polypropylene resin, 15-30 parts of flame retardant, 1-3 parts of coupling agent, 20-26 parts of magnesium oxide, 1-5 parts of toughening agent, 3-5 parts of dispersant and 2-6 parts of antioxidant.

4. The flame-retardant plastic protective shell for lithium-ion batteries according to claim 3, characterized in that: The flame retardant is prepared from 2-aminoethanesulfonic acid, tetrahydrofuran, sodium carbonate and dichloromethane.

5. The flame-retardant plastic protective shell for lithium-ion batteries according to claim 4, characterized in that: The coupling agent is one or more of triethoxysilane and polyethylene glycol trimethoxysilyl propyl ether.

6. A flame-retardant plastic protective shell for lithium-ion batteries according to claim 5, characterized in that: The toughening agent is one or more of ethylene-octene copolymer and ethylene propylene diene monomer rubber.

7. A flame-retardant plastic protective shell for lithium-ion batteries according to claim 6, characterized in that: The dispersant is one or more of polyethylene wax, polypropylene wax and liquid paraffin.

8. The flame-retardant plastic protective shell for lithium-ion batteries according to claim 7, characterized in that: The antioxidant is one or more of antioxidant 1010, antioxidant 168, avocado oil and tert-butylhydroquinone.

9. A method for preparing a flame-retardant plastic protective shell for a lithium-ion battery according to claim 8, characterized in that: The preparation method comprises the following steps: (1) Put polypropylene resin, flame retardant, coupling agent, magnesium oxide, toughening agent, dispersant and antioxidant into a high-speed mixer according to proportion and mix until the material temperature rises and the discharged material is cooled; (2) The cooled mixed material is fed into a twin-screw extruder for melt extrusion, injected into a shell mold, cooled and dried in a water tank, and the flame-retardant plastic protective shell is obtained.

10. The method for preparing a flame-retardant plastic protective shell for a lithium-ion battery according to claim 9, characterized in that: The temperature in step (1) is 90-100°C.

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