A polypropylene composition, its preparation method and application

Abstract

The present invention relates to a polypropylene composition, a preparation method thereof and an application. The polypropylene composition comprises the following components: a polypropylene resin, an environmental improvement agent, an antistatic agent, a filler and an auxiliary agent; the environmental improvement agent is obtained by mixing volcanic stone, a silver ion antibacterial agent and a binder and performing powder granulation. The polypropylene composition not only has a high initial antibacterial rate, but also has a relatively high antibacterial rate after long-term heat treatment, and has good antibacterial effect persistence.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer materials, and more specifically, to a polypropylene composition, a preparation method thereof, and an application thereof. Background Art

[0002] Polypropylene (abbreviation: PP) is a semi-crystalline thermoplastic with high impact resistance, strong mechanical properties, and resistance to a variety of organic solvents and acid-base corrosion. It has a wide range of applications in the industrial field and is one of the common polymer materials.

[0003] With the development of the automotive industry, the requirements for automotive materials are getting higher and higher. The automotive industry has put forward new antibacterial standards for the whole vehicle, which is a huge change for the automotive industry. As a responsible automotive enterprise, Guangqi Honda has also made due contributions to the preparation of antibacterial materials for automotive interior parts. As an essential means of transportation in people's daily lives, automobiles have higher requirements for antibacterial properties inside the vehicle, etc., which is also an important means for automobile manufacturers to enhance the competitiveness of the whole vehicle.

[0004] Regarding the antibacterial properties of polypropylene materials, many studies have been carried out. Currently, the performance that has received more attention is mainly the antibacterial rate, but less attention has been paid to the antibacterial persistence, or the antibacterial persistence of existing polypropylene materials is generally poor. For example, in the Chinese patent named an antibacterial and antiviral automotive air-conditioning housing polypropylene material and its preparation method, antibacterial and antiviral agents are directly added to polypropylene. Although the obtained polypropylene material has a high antibacterial rate, its antibacterial persistence is poor; another example is the Chinese patent named a conductive antibacterial long glass fiber-reinforced polypropylene composite material, its preparation method and application, which improves the antibacterial rate through the synergistic effect of zinc oxide whiskers, glycerol monostearate, and an inorganic silver ion glass carrier, but it does not pay attention to the antibacterial persistence of the material.

[0005] Therefore, it is necessary to develop a polypropylene material with a long-lasting antibacterial effect. Summary of the Invention

[0006] The primary object of the present invention is to overcome the problem of poor antibacterial persistence of polypropylene materials in the above-mentioned prior art, and provide a polypropylene composition. This polypropylene composition not only has a high initial antibacterial rate, but also has a high antibacterial rate after heat treatment for a long time (1000 h), and has good antibacterial effect persistence.

[0007] A further object of the present invention is to provide a preparation method of the above polypropylene composition.

[0008] A further object of the present invention is to provide an application of the above polypropylene composition in the preparation of automotive interior air-conditioning housings, air ducts, instrument panels, sub-instrument panels, seats, or door panels.

[0009] The above object of the present invention is achieved by the following technical solutions:

[0010] A polypropylene composition comprising the following components in parts by weight:

[0011]

[0012] The environmental improver is obtained by mixing and powder granulation of volcanic stone, silver ion antibacterial agent and binder in a mass ratio of 1:(0.7 - 0.9):(0.1 - 0.3).

[0013] The inventors of the present invention found through multiple studies that the environmental improver is prepared by mixing and powder granulating volcanic stone, silver ion antibacterial agent and binder, and then adding the environmental improver and antistatic agent to polypropylene resin. The obtained polypropylene composition not only has a high initial antibacterial rate, but also has a high antibacterial rate after heat treatment for a long time (1000 h), and has good persistence of antibacterial effect. The reason may be that: a large number of pores are distributed on the surface of volcanic stone and it has certain antibacterial properties itself. After mixing and powder granulating volcanic stone, silver ion antibacterial agent and binder, a dense powder particle, that is, the environmental improver, can be obtained. On the one hand, this can effectively prevent the agglomeration of silver ion antibacterial agent and is beneficial to the exertion of its antibacterial effect; on the other hand, this is beneficial to the full contact between silver ion antibacterial agent and volcanic stone, thus playing a synergistic antibacterial role; on this basis, adding an antistatic agent, the antistatic agent has an out-migration effect and can form a channel between the surface and the inside of the polypropylene composition. The silver ion antibacterial agent can be slowly released to the surface of the polypropylene composition through the channel to achieve long-lasting and good antibacterial. In addition, the pores distributed on the surface of volcanic stone in the environmental improver have an adsorption effect and can adsorb VOC gases in the environment, etc., to improve the odor environment.

[0014] In addition, the polypropylene composition of the present invention has good tensile strength, flexural modulus and notched impact strength, all of which can meet the daily use requirements and satisfy various application scenarios.

[0015] Preferably, the polypropylene composition comprises the following components in parts by weight:

[0016]

[0017] Preferably, the melt index of the polypropylene resin is 9 - 30 g / 10 min.

[0018] More preferably, the melt index of the polypropylene resin is 9 - 27 g / 10 min.

[0019] The melt index of the polypropylene resin of the present invention can be measured under the test conditions of 230 °C and 2.16 kg according to the test standard ISO 1133 - 1 / 2:2012.

[0020] Optionally, the polypropylene resin is at least one of a copolymerized polypropylene resin and a homopolypropylene.

[0021] Preferably, the specific process of mixing and powder granulation is as follows: First, mix the volcanic stone and the silver ion antibacterial agent to obtain a mixture, then spray the binder onto the mixture in the form of a spray, and then perform powder granulation through a powder granulation process to obtain the environmental improver.

[0022] More preferably, the mixing is carried out in a high-speed mixer, the mixing time is 5 - 10 min, and the mixing rotation speed is 200 - 300 revolutions per minute.

[0023] Commonly used silver ion antibacterial agents, volcanic stones, binders, antistatic agents, and fillers in the art can all be used in the present invention.

[0024] Optionally, the silver ion antibacterial agent is at least one of silver nitrate, imidazole silver, and benzothiazole silver. Among them, when silver nitrate is selected as the silver ion antibacterial agent, the initial antibacterial effect and antibacterial persistence of the obtained polypropylene composition are better.

[0025] Optionally, the mesh number of the volcanic stone is 800 - 1250 mesh.

[0026] Optionally, the volcanic stone is at least one of a white volcanic stone and a black volcanic stone.

[0027] Optionally, the binder is a polyurethane glue.

[0028] Optionally, the antistatic agent is at least one of ethoxylated stearamide, propylene bis(octadecyl dimethyl ammonium chloride), and octadecyl dimethyl hydroxyethyl ammonium nitrate.

[0029] Preferably, the antistatic agent is octadecyl dimethyl hydroxyethyl ammonium nitrate. When this antistatic agent is selected, the initial antibacterial effect and antibacterial persistence of the obtained polypropylene composition are better.

[0030] Optionally, the filler is at least one of talc powder, mica powder, and wollastonite.

[0031] Optionally, the mesh number of the filler is 800 - 3000 mesh.

[0032] Optionally, the auxiliary agent is at least one of a toughening agent, a lubricant, and an antioxidant.

[0033] Further optionally, the toughening agent is at least one of an ethylene-octene random copolymer, an ethylene-butene random copolymer, and a hydrogenated styrene-butadiene-styrene linear triblock copolymer (abbreviation: SEBS).

[0034] Further optionally, the lubricant includes, but is not limited to, stearate lubricants.

[0035] Further optionally, the antioxidant includes, but is not limited to, at least one of hindered phenol antioxidants or phosphite antioxidants.

[0036] The method for preparing the above polypropylene composition includes the following steps:

[0037] Mix the components, melt-extrude, and granulate to obtain the polypropylene composition.

[0038] Preferably, the melt-extrusion is carried out using a twin-screw extruder.

[0039] More preferably, the temperature of the twin-screw extruder is 170 - 210 °C.

[0040] The application of the above polypropylene composition in preparing automotive interior air-conditioning housings, air ducts, instrument panels, lower instrument panels, seats or door panels is also within the protection scope of the present invention.

[0041] Compared with the prior art, the beneficial effects of the present invention are:

[0042] The polypropylene composition of the present invention not only has a high initial antibacterial rate, but also still has a high antibacterial rate after heat treatment for a long time (1000 h), and the antibacterial effect has good persistence. In addition, the pores distributed on the surface of the volcanic stone in the environmental improvement agent have an adsorption effect, which can adsorb VOC gases in the environment, etc., and improve the odor environment. Detailed Embodiments

[0043] In order to more clearly and completely describe the technical solutions of the present invention, the present invention will be further described in detail below through specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention, and various changes can be made within the scope defined by the claims of the present invention.

[0044] Some of the reagents selected in the embodiments and comparative examples of the present invention are described as follows:

[0045] Polypropylene resin 1#: SZ30S (homopolymer, MFR = 24 g / 10 min), supplier: Wuhan Petrochemical;

[0046] Polypropylene resin 2#: 548R (copolymer, MFR = 27 g / 10 min), supplier: CNOOC and Shell;

[0047] Polypropylene resin 3#: K8009 (copolymer, MFR = 9 g / 10 min), supplier: Wuhan Petrochemical;

[0048] Antistatic agent 1#: Octadecyl dimethyl hydroxyethyl ammonium nitrate, antistatic agent 129, supplier: Croda UK;

[0049] Antistatic agent 2#: Ethoxylated stearic acid amide, Antistatic agent A4-88, Supplier: Jiahua Fine Chemicals;

[0050] Filler 1#: Talc powder, AH-51210, 3000 mesh, Supplier: Liaoning Aihai;

[0051] Filler 2#: Mica powder, YM-SW500, Supplier: Zhongwei Non-Metallic Materials;

[0052] Toughening agent: Ethylene-butene random copolymer, DF605, Supplier: Mitsui Chemicals, Japan;

[0053] Antioxidant: Obtained by mixing Antioxidant 1010 and Antioxidant 168 in a mass ratio of 1:1, where both Antioxidant 1010 and Antioxidant 168 are commercially available;

[0054] Lubricant: Zinc stearate, commercially available;

[0055] Volcanic rock 1#: White volcanic rock, ultrafine ground powder of 800 mesh, Supplier: Yiran Minerals;

[0056] Volcanic rock 2#: Black volcanic rock, ultrafine ground powder of 1250 mesh, Supplier: Huabang Mineral Products;

[0057] Silver ion antibacterial agent 1#: Silver nitrate, 9051-FT-PP, Supplier: Hannuo Polymer Technology;

[0058] Silver ion antibacterial agent 2#: Imidazole silver, analytical pure, Supplier: Anneg Chemical;

[0059] Binder: Spray-type binder, polyurethane glue, Supplier: Miyuan Building Materials Technology;

[0060] Environmental improver 1#, self-made, the preparation process is as follows: First, weigh volcanic rock 1#, silver ion antibacterial agent 1# and binder according to the mass ratio of 5:4:1 respectively; then mix volcanic rock 1# and silver ion antibacterial agent 1# in a high-speed mixer for 10 min (the rotation speed of the high-speed mixer is 300 revolutions per minute) to obtain a mixture; continue to rotate the high-speed mixer, and at the same time spray the binder onto the mixture in the form of a spray; finally, use a single-screw powder granulator for roll pressing, granulation with a 32-hole disc, and screening to obtain dense powder particles, which is environmental improver 1#.

[0061] Environmental improver 2#, self-made, its preparation process is basically the same as that of environmental improver 1#, the difference is that: the mass ratio of volcanic rock 1#, silver ion antibacterial agent 1# and binder is 10:7:1.

[0062] Environmental improver 3#, self-made, the preparation process of which is basically the same as that of environmental improver 1#, the difference lies in that: the mass ratio of volcanic stone 1#, silver ion antibacterial agent 1# and binder is 10:9:3.

[0063] Environmental improver 4#, self-made, the preparation process of which is basically the same as that of environmental improver 1#, the difference lies in that: volcanic stone 1# is replaced by volcanic stone 2#.

[0064] Environmental improver 5#, self-made, the preparation process of which is basically the same as that of environmental improver 1#, the difference lies in that: silver ion antibacterial agent 1# is replaced by silver ion antibacterial agent 2#.

[0065] Environmental improver 6#, self-made, the preparation process of which is basically the same as that of environmental improver 1#, the difference lies in that: no binder is added. Specifically: volcanic stone 1# and silver ion antibacterial agent 1# are mixed in a high-speed mixer according to the mass ratio of 5:4, and then roller-pressed by a single-screw powder granulator and granulated by a 32-hole disc, and screened to obtain environmental improver 6#.

[0066] Environmental improver 7#, self-made, the preparation process of which is basically the same as that of environmental improver 1#, the difference lies in that: no volcanic stone 1# is added. Specifically: silver ion antibacterial agent 1# is added to a high-speed mixer, and under the condition of rotation, the binder is sprayed onto the surface of silver ion antibacterial agent 1# in the form of a spray, and then roller-pressed by a single-screw powder granulator and granulated by a 32-hole disc, and screened to obtain environmental improver 7#.

[0067] Environmental improver 8#, self-made, the preparation process of which is basically the same as that of environmental improver 1#, the difference lies in that: no silver ion antibacterial agent 1# is added. Specifically: volcanic stone 1# is added to a high-speed mixer, and under the condition of rotation, the binder is sprayed onto the surface of volcanic stone 1# in the form of a spray, and then roller-pressed by a single-screw powder granulator and granulated by a 32-hole disc, and screened to obtain environmental improver 8#.

[0068] Unless otherwise specified, the components (such as antioxidants, lubricants, etc.) selected in each parallel example and comparative example are all the same commercially available products.

[0069] The preparation process of the polypropylene compositions in the examples and comparative examples of the present invention is as follows: after weighing each component according to the ratio, it is added to a high-speed mixer and stirred and blended at a speed of 650 revolutions per minute for 4 minutes to obtain a premix. The above-mentioned mixed particles are added to a 75D co-rotating twin-screw extruder for melt extrusion, granulation, drying and cooling to obtain a polypropylene composition. The temperature of the twin-screw extruder from the feeding section to the head is 170°C, 200°C, 200°C, 210°C, 210°C, 205°C, 205°C, 205°C, 200°C, 200°C in turn.

[0070] The polypropylene compositions provided in the embodiments and comparative examples of the present invention were subjected to performance determination according to the following test methods:

[0071] Antibacterial rate: Tested in accordance with ISO 22196-2011, including the initial antibacterial rate and the antibacterial rate after heat treatment for 1000 hours; among them, the initial antibacterial rate was first measured according to the standard; then the sample was heat-treated at 100 °C for 1000 h, and the antibacterial rate after heat treatment was measured again according to the standard;

[0072] Tensile strength: Tested in accordance with ISO 527-2, and the tensile speed was 50 mm / min;

[0073] Flexural modulus: Tested in accordance with ISO 178, and the flexural speed was 2 mm / min;

[0074] Izod notched impact strength: Tested in accordance with ISO 180.

[0075] Examples 1 to 14

[0076] Examples 1 to 14 provided a series of polypropylene compositions, and their formulations are shown in Tables 1 and 2.

[0077] Table 1 Formulations of Examples 1 to 8 (parts by weight)

[0078]

[0079]

[0080] Table 2 Formulations of Examples 9 to 14 (parts by weight)

[0081]

[0082] Comparative Example 1

[0083] This comparative example provided a polypropylene composition, and the difference in its formulation from that of Example 1 was that antistatic agent 1# was not added.

[0084] Comparative Example 2

[0085] This comparative example provided a polypropylene composition, and the difference in its formulation from that of Example 1 was that environmental improver 1# was not added.

[0086] Comparative Example 3

[0087] This comparative example provided a polypropylene composition, and the difference in its formulation from that of Example 1 was that environmental improver 1# was replaced with environmental improver 6#.

[0088] Comparative Example 4

[0089] This comparative example provides a polypropylene composition, the difference in its formulation from that of Example 1 being that: the environmental improvement agent 1# is replaced with the environmental improvement agent 7#.

[0090] Comparative Example 5

[0091] This comparative example provides a polypropylene composition, the difference in its formulation from that of Example 1 being that: the environmental improvement agent 1# is replaced with the environmental improvement agent 8#.

[0092] Comparative Example 6

[0093] This comparative example provides a polypropylene composition, the difference in its formulation from that of Example 1 being that: 13 parts by weight of the environmental improvement agent 1# is replaced with 6.5 parts by weight of volcanic rock 1#, 5.2 parts by weight of silver ion antibacterial agent 1# and 1.3 parts by weight of binder. That is, the volcanic rock 1#, silver ion antibacterial agent 1# and binder are not made into an environmental improvement agent, but the three are directly mixed with polypropylene resin, antistatic agent, filler, toughening agent, antioxidant and lubricant, melt-extruded, granulated, dried and cooled to obtain the polypropylene composition of this comparative example.

[0094] According to the above-mentioned test methods, the polypropylene compositions of each example and comparative example were tested, and the test results are shown in Table 3.

[0095] Table 3 Performance test results of the polypropylene compositions of each example and comparative example

[0096]

[0097]

[0098] As can be seen from Table 3, the initial antibacterial rates of the polypropylene compositions of Examples 1 to 14 all reached more than 95%, and the antibacterial rates after 1000 hours of heat treatment all remained above 75%, indicating that the polypropylene composition of the present invention not only has excellent antibacterial performance, but also has good persistence of antibacterial effect. In addition, the tensile strength of the polypropylene composition of the present invention reached more than 17 MPa, the flexural modulus reached more than 1300 MPa, and the notch impact strength reached 19 KJ / m 2 above, all of which can meet the daily use requirements and satisfy various application scenarios.

[0099] In Comparative Example 1, no antistatic agent was added. Although the initial antibacterial rate of the obtained polypropylene composition was good, the antibacterial rate after heat treatment was significantly low, and the durability of the antibacterial effect was poor. In Comparative Example 2, no environmental improver was added. The obtained polypropylene composition had no antibacterial effect and its mechanical properties were inferior to those of Example 1. In Comparative Example 3, the environmental improver No. 6 added did not contain a binder during the preparation process. The initial antibacterial rate of the obtained polypropylene composition was slightly low, and the antibacterial rate after heat treatment was significantly low. The durability of the antibacterial effect was poor. The reason might be that without adding a binder, the obtained powder was relatively fluffy, and the silver ion antibacterial agent still agglomerated to a certain extent, which was not conducive to exerting the antibacterial effect. In Comparative Example 4, the environmental improver No. 7 added did not contain volcanic stone during the preparation process. The initial antibacterial rate of the obtained polypropylene composition was low, and the antibacterial rate after heat treatment was also low. In Comparative Example 5, the environmental improver No. 8 added did not contain a silver ion antibacterial agent during the preparation process. Both the initial antibacterial rate and the antibacterial rate after heat treatment of the obtained polypropylene composition were very low. In Comparative Example 6, the volcanic stone, silver ion antibacterial agent and binder were not pre-made into an environmental improver by powder granulation, but directly melt-extruded and granulated with components such as polypropylene resin to obtain a polypropylene composition. The silver ion antibacterial agent agglomerated and had poor dispersibility. The initial antibacterial rate of the obtained polypropylene composition was low, the antibacterial rate after heat treatment was also low, and the durability of the antibacterial effect was poor.

[0100] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, rather than limitations on the implementation manners of the present invention. For those of ordinary skill 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 enumerate all the implementation manners here. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A polypropylene composition, characterized in that, It comprises components in the following parts by weight: The environmental improver is obtained by mixing and powder granulation of volcanic stone, silver ion antibacterial agent and binder in a mass ratio of 1:(0.7 - 0.9):(0.1 - 0.3). The specific process of the mixing and powder granulation is as follows: First, the volcanic stone and the silver ion antibacterial agent are mixed to obtain a mixture, then the binder is sprayed onto the mixture in a spray form, and then powder granulation is carried out through a powder granulation process to obtain the environmental improver. The antistatic agent is at least one of ethoxylated stearic acid amide, propylene bis(octadecylamidopropyl dimethyl ammonium chloride) or octadecyl dimethyl hydroxyethyl quaternary ammonium nitrate.

2. The polypropylene composition according to claim 1, wherein, The polypropylene composition comprises components in the following parts by weight:

3. The polypropylene composition according to claim 1, characterized in that, The melt index of the polypropylene resin is 9 - 30 g / 10 min.

4. The polypropylene composition according to claim 1, characterized in that, The silver ion antibacterial agent is at least one of silver nitrate, silver imidazole or silver benzothiazole.

5. The polypropylene composition according to claim 1, characterized in that, The mesh number of the volcanic stone is 800 - 1250 mesh.

6. The polypropylene composition according to claim 1, wherein The auxiliary agent is at least one of a toughening agent, a lubricant or an antioxidant.

7. The preparation method of the polypropylene composition according to any one of claims 1 to 6, characterized in that, It comprises the following steps: Mix the components, melt extrude and granulate to obtain the polypropylene composition.

8. Use of the polypropylene composition according to any one of claims 1 - 6 in the preparation of an automotive interior air-conditioning housing, air duct, instrument panel, lower instrument panel, seat or door panel.

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