Anti-static polypropylene composite material and preparation method thereof

Abstract

The invention discloses an anti-static polypropylene composite material and a preparation method thereof. The anti-static polypropylene composite material is prepared from the following components in parts by weight: 100 parts of polypropylene resin, 0.01-0.05 part of amphiphilic graphene oxide and 1 part of a processing aid. The polar elastomer, the silane coupling agent and the graphene oxide are adopted for graft modification, so that the graphene oxide has amphipathy to polypropylene, namely, the silane coupling agent endows the graphene oxide with relatively good lipophilicity, and the polar elastomer endows the graphene oxide with relatively good hydrophilicity. The amphipathy of graphene oxide is utilized, the hydrophilic end enables siloxane-grafted graphene oxide to tend to migrate to the surface of the composite material, the oleophylic end endows graphene oxide with good compatibility with polypropylene, good dispersion of graphene oxide is guaranteed, a conductive path is formed on the surface layer of the composite material, and the surface of the composite material is protected. Therefore, the surface resistivity of the polypropylene composite material is greatly reduced under the condition of extremely micro addition amount.

Description

Technical Field

[0001] The invention relates to the technical field of polymer material modification, in particular to an antistatic polypropylene composite material and a preparation method thereof. Background Art

[0002] Polypropylene (PP) has the advantages of low density, easy processing, and excellent mechanical properties. It has been widely used in the automotive industry, home appliances, and machinery. With the rapid development of electronic and information technology, the demand for antistatic materials has become more and more urgent. In the field of modified plastics, adding antistatic agents is the most effective way to eliminate static electricity. Commonly used antistatic agents are divided into small molecule short-acting types and polymer long-acting types. Small molecule antistatic agents are added in small amounts and can quickly migrate to the surface of the material. The hydrophilic groups in the molecules absorb water to form a continuous conductive layer on the surface of the material, achieving the effect of static dissipation. However, the antistatic effect of small molecules is greatly affected by the humidity of the environment, and the effect is usually effective for only 3 months. Polymer antistatic agents, also known as polymer antistatic agents, have excellent conductivity and can form a conductive network in the polymer system. They have the characteristics of long-lasting and stable antistatic effect, are not affected by external forces such as wiping, and have little dependence on the relative humidity of the air. Although polymer antistatic agents have the above advantages, their antistatic efficiency is low due to their large molecular weight and difficulty in migration. Therefore, sufficient addition is required to achieve a good antistatic effect. Usually, the addition amount is between 15% and 25%, which is costly. Therefore, the development of an efficient and permanent antistatic polypropylene material has important industrial value. Summary of the invention

[0003] In view of this, the present invention provides an antistatic polypropylene composite material and a preparation method thereof to solve the problems raised in the above-mentioned background technology. Only a very small amount of modified graphene oxide needs to be added to give the polypropylene composite material a higher antistatic effect and maintain higher mechanical properties, thereby solving the shortcomings in the prior art.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] In a first aspect, the present invention discloses an antistatic polypropylene composite material, which is prepared from the following components in parts by weight:

[0006] 100 parts of polypropylene resin,

[0007] 0.01-0.05 parts of amphiphilic graphene oxide,

[0008] 1 part of processing aid.

[0009] As a further solution of the present invention: the amphiphilic graphene oxide is prepared from graphene oxide, a polar elastomer, a silane coupling agent and a peroxide.

[0010] As a further solution of the present invention: the preparation method of the amphiphilic graphene oxide is as follows:

[0011] Under the condition of 160-200° C., graphene oxide, polar elastomer, silane coupling agent and peroxide are mixed and kneaded to obtain a mixed material;

[0012] The cooled mixed product is crushed to obtain amphiphilic graphene oxide.

[0013] As a further solution of the present invention: the mass ratio of the graphene oxide, the polar elastomer, the silane coupling agent and the peroxide is 100:(10-20):(1-3):(0.5-1).

[0014] As a further solution of the present invention: the polar elastomer is at least one of a polyether polyurethane elastomer and a polyester elastomer.

[0015] As a further embodiment of the present invention: the peroxide is at least one of dicumyl peroxide, benzoyl peroxide, lauroyl peroxide, di-tert-butyl peroxide and tert-butyl perbenzoate.

[0016] As a further solution of the present invention: the processing aid is at least one of an antioxidant, an auxiliary antioxidant, a light absorber and a light stabilizer.

[0017] 8. The method for preparing the antistatic polypropylene composite material according to any one of claims 1 to 7, characterized in that it comprises the following steps:

[0018] The polypropylene resin, the amphiphilic graphene oxide and the processing aid are fully mixed according to weight parts to obtain a mixture;

[0019] The mixture is put into a parallel twin-screw extruder, and the mixture is melted, extruded and granulated to obtain an antistatic polypropylene composite material.

[0020] As a further solution of the present invention: the barrel temperature of the parallel twin-screw extruder is 160°C-230°C, the head temperature is 220-225°C, the screw speed is 500-600r / min, the melt pressure is 1.0MPa, and the vacuum degree is -0.06MPa.

[0021] In a second aspect, the present invention discloses the application of the antistatic polypropylene composite material in the automobile industry and the home appliance industry.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The present invention adopts polar elastomer, silane coupling agent and grafting modification of graphene oxide, so that graphene oxide has amphiphilicity to polypropylene, that is, silane coupling agent gives graphene oxide good lipophilicity, and polar elastomer gives graphene oxide good hydrophilicity. Further, in the present invention, only a very small amount of amphiphilic modified graphene oxide needs to be added, so that the surface resistivity of the composite material is greatly reduced. In the processing of polypropylene composite materials, the amphiphilicity of graphene oxide is utilized, and the hydrophilic end makes the siloxane grafted graphene oxide tend to migrate to the surface of the composite material, and the lipophilic end gives graphene oxide good compatibility with polypropylene, ensuring its good dispersion, forming a conductive path on the surface of the composite material, thereby greatly reducing the surface resistivity of the polypropylene composite material under a very small addition amount. In addition, an antistatic polypropylene composite material prepared by the present invention is not affected by the mechanical properties of the composite material before and after the addition of amphiphilic graphene oxide, because the addition amount of amphiphilic graphene oxide is extremely low. DETAILED DESCRIPTION

[0024] For ease of understanding of the present invention, the present invention will be described more fully below in conjunction with specific embodiments. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thoroughly understood.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0026] The specific information of the raw materials used in the following examples and comparative examples is as follows:

[0027] Polypropylene resin, using polypropylene homopolymer (PP-H), brand PPH-T03, density 0.9g / cm 3 , melt index 3.4g / 10min (temperature 230℃, load 2.16Kg), Anqing Petrochemical.

[0028] Graphene oxide, thickness: 0.55-1.2 nm, diameter: 0.5-3 μm, number of layers: 1-5 layers, Zhongke Leiming (Beijing) Technology Co., Ltd.

[0029] The polar elastomer is a polyester elastomer with a brand name of KYLflex L2520 and a Shore hardness of 25D, purchased from Jiangsu Keyilai.

[0030] Silane coupling agent KH550 was purchased from Nanjing Xiangfei Chemical Research Institute.

[0031] The peroxide used was dicumyl peroxide, industrial grade, purchased from Suzhou Senfida Chemical Co., Ltd.

[0032] The processing aids include primary antioxidant, secondary antioxidant, light absorber and light stabilizer, which are mixed in a mass ratio of 1:1:1:1. The primary antioxidant is Irganox 565, manufactured by BASF, Germany. The secondary antioxidant is AN 168, manufactured by Qingdao Deda Special Chemical Group. The light absorber is Chiguard 5050, manufactured by Qitai Co., Ltd. The light stabilizer is LA-52, manufactured by Aidico (China) Investment Co., Ltd.

[0033] All materials are commercially available common products.

[0034] It is to be understood that the above raw materials and reagents are only examples of some specific embodiments of the present invention, so that the technical solution of the present invention is clearer, and it does not mean that the present invention can only use the above reagents, and the specific scope in the claims shall prevail. In addition, the "parts" described in the examples and comparative examples, unless otherwise specified, refer to parts by weight.

[0035] Any range described in the present invention includes the end value and any numerical value between the end values ​​and any sub-range formed by the end value or any numerical value between the end values.

[0036] Example 1

[0037] (1) Weigh 100 parts of graphene oxide, 10 parts of KYLflex L2520, 1 part of silane coupling agent and 0.5 parts of diisopropylbenzene peroxide and add them to a torque rheometer. Mix for 10 minutes, cool and cut into pieces to obtain amphiphilic graphene oxide. Torque rheometer parameters: speed 100 r / min, temperature 180°C.

[0038] (2) weighing 100 parts of polypropylene resin, 0.05 parts of amphiphilic graphene oxide and 1 part of a processing aid, stirring at a speed of 500 r / min for 10 minutes to obtain a mixture;

[0039] (3) The mixture is put into a parallel twin-screw extruder, and the mixture is melted, extruded and granulated to obtain an antistatic polypropylene composite material.

[0040] Among them, the barrel temperature of the parallel twin-screw extruder is 160°C in zone 1, 220°C in zone 2, 220°C in zone 3, 230°C in zone 4, 230°C in zone 5, 230°C in zone 6, and 220°C in the die head, the screw speed is 500r / min, the melt pressure is 1.0MPa, and the vacuum degree is -0.06MPa.

[0041] Example 2

[0042] (1) Weigh 100 parts of graphene oxide, 20 parts of KYLflex L2520, 3 parts of silane coupling agent and 1 part of diisopropylbenzene peroxide and add them to a torque rheometer. Mix for 10 minutes, cool and cut into pieces to obtain amphiphilic graphene oxide. Torque rheometer parameters: speed 100 r / min, temperature 180°C.

[0043] (2) weighing 100 parts of polypropylene resin, 0.04 parts of amphiphilic graphene oxide and 1 part of a processing aid, stirring at a speed of 500 r / min for 10 minutes to obtain a mixture;

[0044] (3) The mixture is put into a parallel twin-screw extruder, and the mixture is melted, extruded and granulated to obtain an antistatic polypropylene composite material.

[0045] Among them, the barrel temperature of the parallel twin-screw extruder is 160°C in zone 1, 220°C in zone 2, 220°C in zone 3, 230°C in zone 4, 230°C in zone 5, 230°C in zone 6, and 220°C in the die head, the screw speed is 500r / min, the melt pressure is 1.0MPa, and the vacuum degree is -0.06MPa.

[0046] Example 3

[0047] (1) Weigh 100 parts of graphene oxide, 16 parts of KYLflex L2520, 2 parts of silane coupling agent and 0.7 parts of diisopropylbenzene peroxide and add them to a torque rheometer. Mix for 10 minutes, cool and cut into pieces to obtain amphiphilic graphene oxide. Torque rheometer parameters: speed 100 r / min, temperature 180°C.

[0048] (2) Weighing 100 parts of polypropylene resin, 0.03 parts of amphiphilic graphene oxide and 1 part of a processing aid, stirring at a speed of 500 r / min for 10 minutes to obtain a mixture;

[0049] (3) The mixture is put into a parallel twin-screw extruder, and the mixture is melted, extruded and granulated to obtain an antistatic polypropylene composite material.

[0050] Among them, the barrel temperature of the parallel twin-screw extruder is 160°C in zone 1, 220°C in zone 2, 220°C in zone 3, 230°C in zone 4, 230°C in zone 5, 230°C in zone 6, and 220°C in the die head, the screw speed is 500r / min, the melt pressure is 1.0MPa, and the vacuum degree is -0.06MPa.

[0051] Example 4

[0052] (1) Weigh 100 parts of graphene oxide, 20 parts of KYLflex L2520, 3 parts of silane coupling agent and 0.5 parts of diisopropylbenzene peroxide and add them to a torque rheometer. Mix for 10 minutes, cool and cut into pieces to obtain amphiphilic graphene oxide. Torque rheometer parameters: speed 100 r / min, temperature 180°C.

[0053] (2) weighing 100 parts of polypropylene resin, 0.02 parts of amphiphilic graphene oxide and 1 part of a processing aid, stirring at a speed of 500 r / min for 10 minutes to obtain a mixture;

[0054] (3) The mixture is put into a parallel twin-screw extruder, and the mixture is melted, extruded and granulated to obtain an antistatic polypropylene composite material.

[0055] Among them, the barrel temperature of the parallel twin-screw extruder is 160°C in zone 1, 220°C in zone 2, 220°C in zone 3, 230°C in zone 4, 230°C in zone 5, 230°C in zone 6, and 220°C in the die head, the screw speed is 500r / min, the melt pressure is 1.0MPa, and the vacuum degree is -0.06MPa.

[0056] Example 5

[0057] (1) Weigh 100 parts of graphene oxide, 20 parts of KYLflex L2520, 3 parts of silane coupling agent and 1 part of diisopropylbenzene peroxide and add them to a torque rheometer. Mix for 10 minutes, cool and cut into pieces to obtain amphiphilic graphene oxide. Torque rheometer parameters: speed 100 r / min, temperature 180°C.

[0058] (2) Weighing 100 parts of polypropylene resin, 0.01 parts of amphiphilic graphene oxide and 1 part of a processing aid, stirring at a speed of 500 r / min for 10 minutes to obtain a mixture;

[0059] (3) The mixture is put into a parallel twin-screw extruder, and the mixture is melted, extruded and granulated to obtain an antistatic polypropylene composite material.

[0060] Among them, the barrel temperature of the parallel twin-screw extruder is 160°C in zone 1, 220°C in zone 2, 220°C in zone 3, 230°C in zone 4, 230°C in zone 5, 230°C in zone 6, and 220°C in the die head, the screw speed is 500r / min, the melt pressure is 1.0MPa, and the vacuum degree is -0.06MPa.

[0061] Comparative Example 1

[0062] (1) Weigh 100 parts of polypropylene resin and 1 part of processing aid, stir at a speed of 500 r / min for 10 minutes to obtain a mixture;

[0063] (2) The mixture is put into a parallel twin-screw extruder, and the mixture is melted, extruded and granulated to obtain an antistatic polypropylene composite material.

[0064] Among them, the barrel temperature of the parallel twin-screw extruder is 160°C in zone 1, 220°C in zone 2, 220°C in zone 3, 230°C in zone 4, 230°C in zone 5, 230°C in zone 6, and 220°C in the die head, the screw speed is 500r / min, the melt pressure is 1.0MPa, and the vacuum degree is -0.06MPa.

[0065] Comparative Example 2

[0066] (1) Weigh 100 parts of polypropylene resin, 0.05 parts of graphene oxide and 1 part of a processing aid, and stir at a speed of 500 r / min for 10 minutes to obtain a mixture;

[0067] (2) The mixture is put into a parallel twin-screw extruder, and the mixture is melted, extruded and granulated to obtain an antistatic polypropylene composite material.

[0068] Among them, the barrel temperature of the parallel twin-screw extruder is 160°C in zone 1, 220°C in zone 2, 220°C in zone 3, 230°C in zone 4, 230°C in zone 5, 230°C in zone 6, and 220°C in the die head, the screw speed is 500r / min, the melt pressure is 1.0MPa, and the vacuum degree is -0.06MPa.

[0069] Comparative Example 3

[0070] (1) Weigh 101 parts of graphene oxide, 10 parts of KYLflex L2520, and 0.5 parts of diisopropylbenzene peroxide and add them to a torque rheometer. Mix for 10 minutes, cool, and cut into pieces to obtain modified graphene oxide. Torque rheometer parameters: speed 100 r / min, temperature 180°C.

[0071] (2) weighing 100 parts of polypropylene resin, 0.05 parts of amphiphilic graphene oxide and 1 part of a processing aid, stirring at a speed of 500 r / min for 10 minutes to obtain a mixture;

[0072] (3) The mixture is put into a parallel twin-screw extruder, and the mixture is melted, extruded and granulated to obtain an antistatic polypropylene composite material.

[0073] Among them, the barrel temperature of the parallel twin-screw extruder is 160°C in zone 1, 220°C in zone 2, 220°C in zone 3, 230°C in zone 4, 230°C in zone 5, 230°C in zone 6, and 220°C in the die head, the screw speed is 500r / min, the melt pressure is 1.0MPa, and the vacuum degree is -0.06MPa.

[0074] Comparative Example 4

[0075] (1) Weigh 110 parts of graphene oxide, 1 part of silane coupling agent and 0.5 parts of diisopropylbenzene peroxide and add them to a torque rheometer. Mix for 10 minutes, cool and cut into pieces to obtain modified graphene oxide. Torque rheometer parameters: speed 100 r / min, temperature 180°C.

[0076] (2) weighing 100 parts of polypropylene resin, 0.05 parts of amphiphilic graphene oxide and 1 part of a processing aid, stirring at a speed of 500 r / min for 10 minutes to obtain a mixture;

[0077] (3) The mixture is put into a parallel twin-screw extruder, and the mixture is melted, extruded and granulated to obtain an antistatic polypropylene composite material.

[0078] Among them, the barrel temperature of the parallel twin-screw extruder is 160°C in zone 1, 220°C in zone 2, 220°C in zone 3, 230°C in zone 4, 230°C in zone 5, 230°C in zone 6, and 220°C in the die head, the screw speed is 500r / min, the melt pressure is 1.0MPa, and the vacuum degree is -0.06MPa.

[0079] Test Case

[0080] The polypropylene composite materials prepared in each embodiment and comparative example were respectively put into an injection molding machine for melting to obtain standard samples; the barrel temperature of the injection molding machine was 220°C and the mold temperature was 60°C. Each standard sample was subjected to experimental tests, and tensile properties, bending properties and impact properties were tested according to ISO standards; injection molding was performed into a 100*100*2mm square plate, and surface resistance was tested, the test standard was referred to GB / T1410-2006, and the test voltage was 500V. The test results are shown in Table 1.

[0081] Table 1

[0082]

[0083] It can be seen from Table 1 that pure polypropylene in Comparative Example 1 is a non-polar polymer, and its own surface resistivity is relatively high. After adding graphene oxide in Comparative Example 2, due to its poor compatibility with polypropylene, it is difficult to form a conductive network, and the surface resistivity only decreases slightly. After adding modified graphene oxide in Comparative Example 3, since the modified graphene oxide only has hydrophilic characteristics, it has poor dispersion, is difficult to form a conductive network, and has a high surface resistivity. After modifying graphene oxide in Comparative Example 4, since the modified graphene oxide only has lipophilic characteristics, it is difficult to migrate to the surface of the material, and the surface resistivity is also high. In Examples 1 to 5, the addition of trace amounts of amphiphilic graphene oxide, due to its amphiphilicity, the silane coupling agent promotes the dispersion of graphene oxide in the composite material, and the polar elastomer promotes the migration of graphene oxide to the surface of the composite material, prompting graphene oxide to be easier to form a conductive path on the surface, and then form a conductive network, so that the surface resistivity of the material is significantly reduced, thereby obtaining an antistatic polypropylene composite material.

[0084] Although this specification is described according to implementation modes, not every implementation mode includes only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

[0085] Therefore, the above description is only a preferred embodiment of the present application and is not intended to limit the scope of implementation of the present application; that is, all equivalent changes made according to the scope of the claims of the present application are within the protection scope of the claims of the present application.

Claims

1. An antistatic polypropylene composite material, characterized in that: It is prepared from the following components in parts by weight: 100 parts of polypropylene resin, 0.01-0.05 parts of amphiphilic graphene oxide, 1 part of processing aid.

2. The antistatic polypropylene composite material according to claim 1, characterized in that: The amphiphilic graphene oxide is prepared from graphene oxide, a polar elastomer, a silane coupling agent and a peroxide.

3. The antistatic polypropylene composite material according to claim 1, characterized in that: The preparation method of the amphiphilic graphene oxide is as follows: Under the condition of 160-200° C., graphene oxide, polar elastomer, silane coupling agent and peroxide are mixed and kneaded to obtain a mixed material; The cooled mixed product is crushed to obtain amphiphilic graphene oxide.

4. The antistatic polypropylene composite material according to claim 2 or 3, characterized in that: The mass ratio of the graphene oxide, the polar elastomer, the silane coupling agent and the peroxide is 100:(10-20):(1-3):(0.5-1).

5. The antistatic polypropylene composite material according to claim 2 or 3, characterized in that: The polar elastomer is at least one of a polyether polyurethane elastomer and a polyester elastomer.

6. The antistatic polypropylene composite material according to claim 1, characterized in that: The peroxide is at least one of dicumyl peroxide, benzoyl peroxide, lauroyl peroxide, di-tert-butyl peroxide, and tert-butyl perbenzoate.

7. The antistatic polypropylene composite material according to claim 1, characterized in that: The processing aid is at least one of an antioxidant, an auxiliary antioxidant, a light absorber and a light stabilizer.

8. The method for preparing the antistatic polypropylene composite material according to any one of claims 1 to 7, characterized in that: The following steps are involved: The polypropylene resin, the amphiphilic graphene oxide and the processing aid are fully mixed according to weight parts to obtain a mixture; The mixture is put into a parallel twin-screw extruder, and the mixture is melted, extruded and granulated to obtain an antistatic polypropylene composite material.

9. The preparation method according to claim 8, characterized in that: The barrel temperature of the parallel twin-screw extruder is 160° C.-230° C., the head temperature is 220-225° C., the screw speed is 500-600 r / min, the melt pressure is 1.0 MPa, and the vacuum degree is -0.06 MPa.

10. Application of the antistatic polypropylene composite material according to any one of claims 1 to 7 in the automobile industry and the home appliance industry.

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