Polypropylene composite material as well as preparation method and application thereof

Abstract

The invention discloses a polypropylene composite material as well as a preparation method and application thereof. The polypropylene composite material comprises the following components in parts by weight: 30-51 parts of polypropylene resin A; 12 to 20 parts of homo-polypropylene; 30 to 40 parts of polypropylene resin B; 4-8 parts of a halogen-free flame retardant; 2-4 parts of a toughening agent; the ethylene content in the polypropylene resin A is 9-13wt%, and the ethylene content in the polypropylene resin B is 2.8-5wt%; the melt flow rate of the homo-polypropylene is not less than 20g / 10min at 230 DEG C under the load of 2.16 kg. According to the polypropylene composite material, polypropylene resins with different ethylene contents are compounded, and homo-polypropylene with a specific melt flow rate is added, so that the polypropylene composite material with relatively good light transmittance, flame retardance and falling ball impact performance can be obtained, and the polypropylene composite material is particularly suitable for a high-speed rail storage battery material.

Description

Technical Field

[0001] The invention belongs to the field of modified plastics, and more specifically, relates to a polypropylene composite material and a preparation method and application thereof. Background Art

[0002] Polypropylene resin is a crystalline polymer material. Polypropylene resin is widely used in battery materials such as lead-acid batteries, flow batteries, and alkaline batteries due to its solvent resistance, high ductility, impact resistance, and easy hot-melt welding properties.

[0003] Alkaline storage battery materials for high-speed rail require flame retardancy not less than V-2 and resistance to falling ball impact. With the continuous advancement of my country's high-speed rail construction, the technical requirements for supporting products on high-speed rail are also gradually increasing. Since alkaline storage batteries consume a certain amount of electrolyte during operation, there are gradually requirements for transparency of materials to achieve liquid level visualization. Conventional flame-retardant polypropylene products on the market do not have light-transmitting properties, and the liquid level cannot be visualized. The flame retardant properties of existing light-transmitting polypropylene materials are unstable and cannot guarantee the safety of the use process. In the prior art, polypropylene materials with good flame retardancy and transparency are obtained by compounding bromide flame retardants and hypophosphites, but their falling ball impact performance cannot meet the requirements. Therefore, there is a need in the art for a polypropylene composite material that has good falling ball impact performance, flame retardancy and transparency. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects or shortcomings of the prior art polypropylene materials that cannot have both light transmittance, flame retardancy and falling ball impact performance, and to provide a polypropylene composite material.

[0005] Another object of the present invention is to provide a method for preparing the polypropylene composite material.

[0006] Another object of the present invention is to provide application of the polypropylene composite material.

[0007] To achieve the above object, the present invention is implemented through the following technical solutions:

[0008] A polypropylene composite material, comprising the following components calculated in parts by weight:

[0009]

[0010]

[0011] The ethylene content of the polypropylene resin A is 9-13wt%, and the ethylene content of the polypropylene resin B is 2.8-5wt%; the melt flow rate of the homopolypropylene at 230° C. and 2.16kg load is not less than 20g / 10min.

[0012] In the present invention, the inventors use three kinds of polypropylene resins for compounding, use homopolymer polypropylene and compound two kinds of polypropylene resins with ethylene content, and then add a proper amount of halogen-free flame retardant to obtain a polypropylene composite material with flame retardancy, transparency and good falling ball impact performance; specifically, polypropylene resin A can play a toughening role, homopolymer polypropylene can promote dripping, and polypropylene resin B can reduce the average spherulite size of the system and improve the light transmittance of the composite material, so that the obtained polypropylene composite material can have good flame retardancy, transparency and impact performance.

[0013] It should be noted that, in the polypropylene composite material of the present invention, the content of the polypropylene resin A is preferably not less than 28 wt %.

[0014] It should be noted that the ethylene content in the polypropylene resin A of the present invention is 9-13wt%, for example but not limited to 9wt%, 9.2wt%, 9.5wt%, 9.8wt%, 10wt%, 10.2wt%, 10.5wt%, 10.8wt%, 11wt%, 11.2wt%, 11.5wt%, 11.8wt%, 12wt%, 12.2wt%, 12.5wt%, 12.8wt% or 13wt%, etc. can all achieve the present invention. Further, the ethylene content in the polypropylene resin A is 10-12.8wt%.

[0015] The ethylene content in the polypropylene resin B of the present invention is 2.8-5wt%, such as but not limited to 2.8wt%, 2.9wt%, 3wt%, 3.1wt%, 3.2wt%, 3.3wt%, 3.4wt%, 3.5wt%, 3.6wt%, 3.7wt%, 3.8wt%, 3.9wt%, 4wt%, 4.1wt%, 4.2wt%, 4.3wt%, 4.4wt%, 4.5wt%, 4.6wt%, 4.7wt%, 4.8wt%, 4.9wt% or 5wt%, etc. can all realize the present invention. Further, the ethylene content in the polypropylene resin B is 3-4.8wt%.

[0016] Furthermore, the ethylene content is measured by infrared spectroscopy.

[0017] Specifically, 4482-3950cm -1 The absorption area within the range is used as the measurement parameter of polypropylene.

[0018] When the ethylene content is less than 8%, the -1 The absorption area in the range of 777 to 679 cm is used as the determination parameter of ethylene. When the ethylene content is between 8% and 20%, the absorption area in the range of 777 to 679 cm is used as the determination parameter of ethylene. -1The absorption area within the range was used as the determination parameter of ethylene. The absorbance was calculated using the peak area method, and then the ethylene content was calculated based on the standard curve.

[0019] The homopolymer polypropylene of the present invention has a melt flow rate of not less than 20 g / 10 min at 230° C. and 2.16 kg load, such as but not limited to not less than 20 g / 10 min, 22 g / 10 min, 25 g / 10 min, 28 g / 10 min, 30 g / 10 min, 32 g / 10 min, 35 g / 10 min, 38 g / 10 min, 40 g / 10 min, 42 g / 10 min, 45 g / 10 min, 48 g / 10 min, 50 g / 10 min, 52 g / 10 min, 55 g / 10 min, 58 g / 10 min, 60 g / 10 min, 62 g / 10 min or 65 g / 10 min, etc., all of which can achieve the present invention. Further, the homopolymer polypropylene has a melt flow rate of 25 to 60 g / 10 min at 230° C. and 2.16 kg load.

[0020] Furthermore, the polypropylene resin A has a melt flow rate of 2 to 15 g / 10 min at 230° C. and a load of 2.16 kg.

[0021] Furthermore, the polypropylene resin A has a melt flow rate of 5 to 12 g / 10 min at 230° C. and a load of 2.16 kg.

[0022] Furthermore, the polypropylene resin B has a melt flow rate of 0.1 to 30 g / 10 min at 230° C. and a load of 2.16 kg.

[0023] Furthermore, the polypropylene resin B has a melt flow rate of 0.2 to 4 g / 10 min at 230° C. and a load of 2.16 kg.

[0024] Specifically, the test standard for the melt flow rate in the present invention is ISO 1133-2011.

[0025] Furthermore, the halogen-free flame retardant is hypophosphite.

[0026] Furthermore, the hypophosphite includes aluminum hypophosphite and / or calcium hypophosphite.

[0027] Furthermore, the average particle size D50 of the halogen-free flame retardant is 4 to 15 μm.

[0028] Furthermore, the toughening agent includes one or more of ethylene-octene copolymer, ethylene-vinyl acetate or ethylene propylene diene monomer rubber.

[0029] Furthermore, the polypropylene composite material comprises the following components calculated in parts by weight:

[0030]

[0031] Furthermore, the polypropylene composite material also includes 0.1 to 5 parts of auxiliary agents.

[0032] Specifically, the auxiliary agent includes an antioxidant and / or a lubricant.

[0033] In the present invention, commonly used antioxidants may be selected, such as but not limited to hindered phenol antioxidants and / or phosphite antioxidants.

[0034] Specifically, the hindered phenol antioxidant is one or more of N,N'-hexamethylenebis(3,5-di-tert-butyl-4-hydroxyphenylpropionamide) (Irganox 1098), pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (Irganox 1010), 1,6-hexanediol bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (Irganox 259), β-(4-hydroxy-3,5-di-tert-butylphenyl)propionic acid n-octadecyl (Irganox 1076) or 3,9-bis{2-[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)acrylate]-1,1-dimethyl}-2,4,8,10-tetraoxaspirocycloundecane (ADK AO-80).

[0035] The phosphite antioxidant is one or more of tris(2,4-di-tert-butylphenyl)phosphite (Irganox 168), bis(2,6-di-tert-butyl-4-tolyl) pentaerythritol phosphite (PEP-36) or 627A.

[0036] In the present invention, commonly used lubricants may be selected, such as but not limited to one or more of vinyl bisstearamide, calcium stearate, oleamide, erucamide, magnesium stearate, zinc stearate, PE wax, or PP wax.

[0037] The present invention also protects a method for preparing the above-mentioned polypropylene composite material, comprising the following steps:

[0038] S1. Blending homopolymer polypropylene and halogen-free flame retardant in a mass ratio of 1:1, extruding and granulating to obtain flame retardant masterbatch;

[0039] S2. Evenly mix the flame retardant masterbatch and other components, and obtain a polypropylene composite material by melting, extruding and granulating.

[0040] Specifically, the conditions for extrusion granulation in step S1 are: the temperature of zone 1 is 120-140°C; the temperature of zone 2 to zone 3 is 180-200°C; the temperature of zone 4 to zone 6 is 190-210°C; the temperature of zone 7 is 180-200°C; the temperature of zone 8 to zone 9 is 190-210°C; and the speed of the extruder is 300-600rpm.

[0041] Specifically, step S2 uses a twin-screw extruder.

[0042] Specifically, the temperature of the twin-screw extruder is 190-210°C; further, the temperature of zone 1 is 120-140°C; the temperature of zones 2 to 3 is 180-200°C; the temperature of zones 4 to 6 is 190-210°C; the temperature of zone 7 is 180-200°C; the temperature of zones 8 to 9 is 190-210°C.

[0043] Specifically, the rotation speed of the twin-screw extruder is 300-600 rpm.

[0044] The present invention also provides the use of the polypropylene composite material in preparing household goods, electronic components, household appliances, gardening equipment, medical technology equipment, motor vehicle parts and body parts. In particular, the polypropylene composite material can be used to prepare articles with good transparency, flame retardancy and impact resistance. In particular, the use in preparing battery materials, especially in battery tank materials.

[0045] Compared with the prior art, the present invention has the following beneficial effects:

[0046] The invention provides a polypropylene composite material. By compounding a homopolymerized polypropylene resin and two polypropylene resins with specific ethylene contents, and adding a halogen-free flame retardant and a toughening agent, a polypropylene composite material with good transparency and flame retardancy can be obtained, and at the same time, good falling ball impact performance is also obtained. DETAILED DESCRIPTION

[0047] The present invention is further described in detail below in conjunction with specific examples, which are only used to explain the present invention and are not used to limit the scope of the present invention. The test methods used in the following examples are conventional methods unless otherwise specified; the materials and reagents used are reagents and materials that can be obtained from commercial channels unless otherwise specified.

[0048] 1. Raw materials used in each embodiment and comparative example:

[0049] Polypropylene resin A:

[0050] Polypropylene resin A1: SP179, with a measured ethylene content of 10.5 wt%, purchased from Lanzhou Petrochemical;

[0051] Polypropylene resin A2: K9010, with a measured ethylene content of 12.6 wt%, purchased from Formosa Chemical Corporation;

[0052] Polypropylene resin A3: EP300M, with a measured ethylene content of 7.7 wt%, purchased from Basel;

[0053] Polypropylene resin A4: 7032E3, with a measured ethylene content of 13.5 wt%, purchased from ExxonMobil;

[0054] Homopolymer polypropylene:

[0055] Homopolymer polypropylene 1: Z30S, melt flow rate 27 g / 10 min, purchased from Zhenhai Refining and Chemical;

[0056] Homopolymer polypropylene 2: HX3800, melt flow rate 45 g / 10 min, purchased from SK Global Chemical;

[0057] Homopolymer polypropylene 3: H9018, melt flow rate 54 g / 10 min, purchased from Lanzhou Petrochemical;

[0058] Homopolymer polypropylene 4: HP500N, melt flow rate 12 g / 10 min, purchased from LyondellBasell;

[0059] Polypropylene resin B:

[0060] Polypropylene resin B1: 5018T, with a measured ethylene content of 3.4 wt%, purchased from Taiwan Plastics, China;

[0061] Polypropylene resin B2: RP242G, with a measured ethylene content of 4.8 wt%, purchased from LyondellBasell;

[0062] Polypropylene resin B3: J-570S, with a measured ethylene content of 2.2 wt%, purchased from Lotte Chemical;

[0063] Polypropylene resin B4: 4220, with an ethylene content of 5.6 wt%, purchased from Yanshan Petrochemical;

[0064] Halogen-free flame retardants:

[0065] Halogen-free flame retardant 1: aluminum hypophosphite, average particle size D50 is 10 μm, purchased from Hubei Hanye Chemical Industry;

[0066] Halogen-free flame retardant 2: aluminum hypophosphite, average particle size D50 is 5 μm, purchased from Suzhou Lianxiong;

[0067] Halogen-free flame retardant 3: calcium hypophosphite, average particle size D50 is 7 μm, purchased from Wuhan Jiyesheng;

[0068] Brominated flame retardant: decabromodiphenylethane, average particle size D50 is 6 μm, purchased from Albemarle, USA;

[0069] Toughener: ethylene-octene copolymer, POE 7447, purchased from Dow Chemical;

[0070] Additives:

[0071] Antioxidant: a compound of hindered phenol antioxidant (antioxidant 1010) and phosphite antioxidant (antioxidant 168) in a mass ratio of 1:1, commercially available;

[0072] Lubricant: erucamide, commercially available;

[0073] It should be noted that the same raw materials used in the embodiments and comparative examples of the present invention have the same source.

[0074] 2. The polypropylene composite materials described in each embodiment and comparative example were prepared according to the formulations in Tables 1 to 2 by the following preparation method:

[0075] S1. The homopolymer polypropylene and the halogen-free flame retardant are blended in a mass ratio of 1:1, and extruded and granulated to obtain a flame retardant masterbatch; the extrusion granulation conditions are: the temperature of zone 1 is 130°C; the temperature of zone 2 to zone 3 is 190°C; the temperature of zone 4 to zone 6 is 200°C; the temperature of zone 7 is 190°C; the temperature of zone 8 to zone 9 is 200°C; the speed of the extruder is 500rpm;

[0076] S2. The flame retardant masterbatch and other components are mixed evenly, and a twin-screw extruder is used to melt, extrude and granulate to obtain a polypropylene composite material; the temperature of zone 1 of the twin-screw extruder is 130°C; the temperature of zones 2 to 3 is 190°C; the temperature of zones 4 to 6 is 200°C; the temperature of zone 7 is 190°C; the temperature of zones 8 to 9 is 200°C; the rotation speed of the twin-screw extruder is 500rpm.

[0077] 3. Performance test:

[0078] (1) Light transmittance test: The polypropylene composite materials prepared in each embodiment and comparative example were injection molded into a 3 mm*100 mm*100 mm square plate, and the light transmittance was tested using a light transmittance meter (a light transmittance of 35% or more was considered acceptable);

[0079] (2) Flame retardancy test: The polypropylene composite materials prepared in each embodiment and comparative example were injection molded into 125 mm*13 mm*2 mm strips and tested with reference to UL94-2013 standard;

[0080] (3) Drop ball impact performance test: The polypropylene composite material prepared in each embodiment and comparative example was injection molded into a 3 mm*100 mm*100 mm square plate, and a 500 g steel ball was used to impact the sample for 1 m, and whether cracking occurred was recorded;

[0081] Examples 1 to 9 and Comparative Examples 1 to 7

[0082] Table 1 Amount (unit: weight parts) and properties of each component in the polypropylene composite material in Examples 1 to 9

[0083] Example 1 2 3 4 5 6 7 8 9 Polypropylene resin A1 41 / 41 41 41 41 50 30 41 Polypropylene resin A2 / 41 / / / / / / / Homopolymer polypropylene 1 15 15 / / 15 15 20 12 15 Homopolymer polypropylene 2 / / 15 / / / / / / Homopolymer polypropylene 3 / / / 15 / / / / / Polypropylene resin B1 35 35 35 35 / 35 40 30 35 Polypropylene resin B2 / / / / 35 / / / / Halogen-free flame retardant 1 6 6 6 6 6 / 4 8 / Halogen-free flame retardant 2 / / / / / 6 / / / Halogen-free flame retardant 3 / / / / / / / / 6 Toughening agent 3 3 3 3 3 3 2 4 3 Antioxidants 0.5 0.5 0.5 0.5 0.5 0.5 / 1.5 0.5 Lubricants 0.3 0.3 0.3 0.3 0.3 0.3 / 1 0.3 Light transmittance (%) 43 41 39 38 41 46 47 37 40 Drop ball impact test intact intact intact intact intact intact intact intact intact Vertical combustion V-2 V-2 V-2 V-2 V-2 V-2 V-2 V-2 V-2

[0084] Table 2 Amount (unit: weight parts) and performance of each component in each comparative example 1 to 7

[0085]

[0086]

[0087] The polypropylene composite material prepared by the invention has good flame retardancy, transparency and falling ball impact performance. Specifically, the flame retardancy level can meet V-2 level, the samples are intact in the falling ball impact test, and the light transmittance is not less than 35%.

[0088] It can be seen from Comparative Examples 1 and 2 that if the ethylene content in the polypropylene resin A is too low or too high, the polypropylene composite material may crack in a falling ball impact test or its flame retardant performance may decrease.

[0089] It can be seen from Comparative Examples 3 and 4 that if the ethylene content in the polypropylene resin B is too low or too high, the resulting polypropylene composite material may crack in a falling ball impact test or have reduced flame retardancy.

[0090] It can be seen from Comparative Example 5 that if polypropylene resin with a moderate ethylene content is directly used, it will cause cracking due to falling ball impact and low light transmittance.

[0091] It can be seen from Comparative Example 6 that if the melt flow rate of the homopolymer polypropylene used is too low, the vertical burning performance does not meet V-2.

[0092] It can be seen from Comparative Example 7 that if other flame retardants are used, the vertical combustion performance does not meet V-2, and the light transmittance and falling ball impact performance cannot meet the requirements.

[0093] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A polypropylene composite material, characterized in that: The composition comprises the following components calculated by weight: The ethylene content of the polypropylene resin A is 9-13wt%, and the ethylene content of the polypropylene resin B is 2.8-5wt%; the melt flow rate of the homopolypropylene at 230° C. and 2.16kg load is not less than 20g / 10min.

2. The polypropylene composite material according to claim 1, characterized in that: The homopolypropylene has a melt flow rate of 25 to 60 g / 10 min at 230° C. and a load of 2.16 kg.

3. The polypropylene composite material according to claim 1, characterized in that: The melt flow rate of the polypropylene resin A at 230° C. and a load of 2.16 kg is 2 to 15 g / 10 min; preferably, the melt flow rate of the polypropylene resin A at 230° C. and a load of 2.16 kg is 5 to 12 g / 10 min.

4. The polypropylene composite material according to claim 1, characterized in that: The melt flow rate of the polypropylene resin B at 230° C. and a load of 2.16 kg is 0.1 to 30 g / 10 min; preferably, the melt flow rate of the polypropylene resin B at 230° C. and a load of 2.16 kg is 0.2 to 4 g / 10 min.

5. The polypropylene composite material according to claim 1, characterized in that: The halogen-free flame retardant is hypophosphite.

6. The polypropylene composite material according to claim 1, characterized in that: The toughening agent includes one or more of ethylene-octene copolymer, ethylene-vinyl acetate or ethylene propylene diene monomer rubber.

7. The polypropylene composite material according to claim 1, characterized in that: It also includes 0.1 to 5 parts of auxiliary agents.

8. The polypropylene composite material according to claim 7, characterized in that: The auxiliary agent includes one or more of an antioxidant, a lubricant, a weathering agent or a toner.

9. A method for preparing the polypropylene composite material according to any one of claims 1 to 8, characterized in that: The steps include: S1. Blending homopolypropylene and halogen-free flame retardant in a mass ratio of 1:1, extruding and granulating to obtain flame retardant masterbatch; S2. Evenly mix the flame retardant masterbatch and other components, and obtain a polypropylene composite material by melting, extruding and granulating.

10. Use of the polypropylene composite material according to any one of claims 1 to 8 in the preparation of battery materials.

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