Low-odor regenerated polypropylene composite material as well as preparation method and application thereof

Abstract

The invention relates to a low-odor regenerated polypropylene composite material as well as a preparation method and application thereof. The composite material comprises 60-80 parts of polypropylene resin; 5-10 parts of a toughening agent; 20 to 30 parts of a filling agent; 0.2 to 0.5 part of an antioxidant; 0.2 to 0.5 part of a lubricant; 0.2 to 3 parts of compatilizer; and 0.3 to 1.5 parts of an odor inhibitor. Wherein the odor inhibitor is a compound of an MOFs material and TiO2 nanoparticles, the prepared MOFs material not only has high porosity, high specific surface area and a micro-mesoporous structure, but also is rich in a conjugated benzene ring structure and an oxygen-containing functional group, can adsorb volatile odor substances generated by melt extrusion of a polypropylene reclaimed material, and can be used for preparing the odor inhibitor by combining the photocatalysis of TiO2. Organic molecules emitted by a material system are further effectively decomposed, the smell is greatly improved through the synergistic effect, the polypropylene material can be applied to interior and exterior trim parts of automobiles, and recycling of waste polypropylene is effectively promoted.

Description

Technical Field

[0001] The invention belongs to the technical field of polymer composite materials, and in particular is a low-odor recycled polypropylene composite material and a preparation method and application thereof. Background Art

[0002] With the development of society, all walks of life have higher and higher requirements for "environmental protection and low carbon", which undoubtedly brings new challenges to the traditional manufacturing automobile industry, requiring low carbon, green and environmental protection to be implemented in the production and manufacturing process of vehicles. With the introduction of concepts such as lightweight automobiles and "plastics instead of steel", the proportion of plastic materials used in complete vehicles is increasing. Therefore, strengthening policy guidance on the application of recycled plastics in the automotive industry, improving the utilization rate of recycled plastics, and expanding the proportion of recycled plastics in complete vehicles are of great significance to achieving the goal of carbon neutrality in the automotive industry.

[0003] Recycled plastics refer to plastic raw materials obtained by processing waste plastics through physical or chemical methods such as pretreatment, melt granulation, and modification. Through the recycling of resources, real environmental protection, carbon reduction and sustainable circulation are achieved. At present, recycled polypropylene material is one of the most recycled and widely used recycled plastics. Although some mechanical properties of recycled polypropylene materials can basically meet the requirements in practical applications, they usually have unbearable odors and high VOC content. Therefore, it is of great significance to develop a low-odor recycled polypropylene composite material and its preparation method and application. Summary of the invention

[0004] The purpose of the present invention is to provide a low-odor recycled polypropylene composite material and a preparation method and application thereof, so as to solve the problem of unbearable odor and high VOC content of recycled polypropylene materials in the background technology.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A low-odor recycled polypropylene composite material comprises the following raw materials: PP resin, toughening agent, filler, antioxidant, lubricant, compatibilizer and odor inhibitor.

[0007] Furthermore, the low-odor recycled polypropylene composite material comprises the following raw materials in parts by weight:

[0008]

[0009] Furthermore, the odor inhibitor is composed of MOFs material and TiO 2 Compounded.

[0010] Furthermore, the odor inhibitor is composed of MOFs material and TiO 2It is compounded according to the mass ratio of 1:0.5~2.

[0011] Further, the synthesis steps of the MOFs material are as follows:

[0012] Add a zirconium source and benzoic acid to N,N-dimethylformamide, then add 1,3,6,8-tetrakis(4-carboxyphenyl)pyrene, transfer to a sealed container, heat to 110-120°C, maintain for 24-48 hours, centrifuge, wash, soak, centrifuge, and dry to obtain a MOFs material.

[0013] Furthermore, the TiO 2 Anatase TiO 2 , particle size is 50~100nm.

[0014] Furthermore, the zirconium source is ZrOCl 2 8H 2 O or ZrCl 4 .

[0015] Furthermore, the mass ratio of the zirconium source, benzoic acid, N,N-dimethylformamide and 1,3,6,8-tetrakis(4-carboxyphenyl)pyrene is 3:50:180:1.

[0016] Furthermore, the PP resin is a mixture of recycled polypropylene and copolymerized polypropylene.

[0017] Furthermore, the cleaning solvent is N,N-dimethylformamide; and the soaking solvent is acetone.

[0018] Furthermore, the recycled polypropylene is light grey opaque particles obtained by washing, crushing and extruding recycled polypropylene plastic.

[0019] Furthermore, the toughening agent is at least one of ethylene-octene copolymer, ethylene-butene copolymer, ethylene-propylene-propylene-α-olefin copolymer, propylene-α-olefin copolymer, and styrene-ethylene-propylene-styrene block copolymer.

[0020] Furthermore, the filler is at least one of talc, calcium carbonate, barium sulfate, wollastonite and mica.

[0021] Furthermore, the antioxidant is at least one of hindered phenol, thioester and phosphite antioxidants.

[0022] Furthermore, the hindered phenol antioxidant is pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate], the thioester antioxidant is distearyl thiodipropionate, and the phosphite antioxidant is tris(2,4-di-tert-butylphenyl) phosphite.

[0023] Furthermore, the lubricant is at least one of silicone, polyethylene wax, calcium stearate, zinc stearate, and ethylene bisstearamide.

[0024] A method for preparing a low-odor recycled polypropylene composite material comprises the following steps:

[0025] PP resin, toughening agent, filler, antioxidant, lubricant compatibilizer and odor inhibitor are mixed, stirred at a speed of 300-500 r / min for 5-10 minutes to obtain a mixture; the mixture is put into a parallel twin-screw extruder for melting, extrusion and granulation to obtain a low-odor recycled polypropylene composite material.

[0026] The barrel temperature of the parallel twin-screw extruder is 180-220° C., the screw speed is 400-600 r / min, the melt pressure is 1.5-2.5 MPa, and the vacuum degree is -0.06--0.1 MPa.

[0027] Application of a low-odor recycled polypropylene composite material: The low-odor recycled polypropylene composite material prepared by the present invention is mainly used in the preparation of automotive interior and exterior trims.

[0028] Beneficial effects of the present invention:

[0029] 1. The low-odor recycled polypropylene composite material prepared by the present invention can meet the development needs of green and recycled materials for automobiles.

[0030] 2. The low-odor recycled polypropylene composite material prepared by the present invention, wherein the odor inhibitor is composed of a MOFs material with an adsorption function and a TiO 2 The MOFs material prepared by the present invention not only has high porosity, high specific surface area and micro-mesoporous structure (1-3nm), but also is rich in conjugated benzene ring structure and oxygen-containing functional groups. It can absorb benzene, aldehydes and other small molecules produced by melt extrusion of polypropylene recycled materials through conjugation, hydrogen bonding and physical action, and introduce TiO 2 Afterwards, it exerts its catalytic effect under visible light to further effectively decompose the organic molecules emitted by the material system, thereby achieving odor improvement through synergistic effects and effectively inhibiting the emission of odor.

[0031] 3. The preparation process of the present invention is simple and can be mass-produced. The odor of the extruded particles or products is significantly improved. DETAILED DESCRIPTION

[0032] 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.

[0033] 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.

[0034] Example 1

[0035] This embodiment provides a MOFs material, which is synthesized by the following steps:

[0036] 0.3 g ZrOC l 2 8H 2 O and 5g benzoic acid were fully dissolved in 18g N,N-dimethylformamide, and then 0.1g 1,3,6,8-tetrakis(4-carboxyphenyl)pyrene was added, transferred to a reactor, heated to 120°C and maintained for 24h. After the reaction was completed, centrifuged at 8000r / min, and washed with N,N-dimethylformamide at 8000r / min. The precipitate was soaked in 50mL acetone for 12h, centrifuged at 8000r / min, and maintained in a vacuum drying oven at 120°C for 12h to obtain MOFs material, and the powder was light yellow.

[0037] Example 2

[0038] This embodiment provides a MOFs material, which is synthesized by the following steps:

[0039] 0.6 g ZrCl 4 and 10g benzoic acid were fully dissolved in 36g N,N-dimethylformamide, and then 0.2g 1,3,6,8-tetrakis(4-carboxyphenyl)pyrene was added, transferred to a reactor, heated to 110°C and maintained for 48h. After the reaction was completed, centrifuged at 8000r / min, and washed with N,N-dimethylformamide at 8000r / min. The precipitate was soaked in 50mL acetone for 12h, centrifuged at 8000r / min, and maintained in a vacuum drying oven at 120°C for 12h to obtain MOFs material, and the powder was light yellow.

[0040] Example 3

[0041] This embodiment provides a low-odor recycled polypropylene composite material, and the preparation method includes the following steps:

[0042] POE LC565 was used as a toughening agent, talc was used as a filler, pentaerythritol tetrakis [B-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate and distearyl thiodipropionate were compounded in a mass ratio of 1:1 as an antioxidant, calcium stearate was used as a lubricant, and PP-g-MAH was used as a compatibilizer. The MOFs material prepared in Example 1 was mixed with nano TiO 2 Compounded as an odor suppressant;

[0043] Among them, TiO 2 Anatase TiO 2 , the particle size is 50-100nm, the recycled polypropylene is light grey opaque particles, which are obtained by washing, crushing and extruding the recycled polypropylene plastic;

[0044] According to the ratio in Table 1, the recycled PP resin, copolymerized PP resin, toughening agent, filler, antioxidant, lubricant, compatibilizer and odor inhibitor were stirred at a speed of 300 r / min for 10 min to obtain a mixture;

[0045] The mixture was put into a parallel twin-screw extruder with a barrel temperature of 180°C, a screw speed of 400 r / min, a melt pressure of 1.5 MPa, and a vacuum degree of -0.06 MPa. The low-odor recycled polypropylene composite material was obtained by melting, extrusion and granulation.

[0046] Example 4

[0047] This embodiment provides a low-odor recycled polypropylene composite material, and the preparation method includes the following steps:

[0048] POE875L was used as a toughening agent, calcium carbonate was used as a filler, pentaerythritol tetrakis [B-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate and distearyl thiodipropionate were compounded in a mass ratio of 1:1 as an antioxidant, silicone was used as a lubricant, PP-g-MAH was used as a compatibilizer, and the MOFs material prepared in Example 1 was mixed with nano TiO 2 Compounded as an odor suppressant;

[0049] According to the ratio in Table 1, the recycled PP resin, copolymerized PP resin, toughening agent, filler, antioxidant, lubricant, compatibilizer and odor inhibitor were stirred at a speed of 300 r / min for 10 min to obtain a mixture;

[0050] The mixture was put into a parallel twin-screw extruder with a barrel temperature of 220°C, a screw speed of 600 r / min, a melt pressure of 2.5 MPa, and a vacuum degree of -0.1 MPa. The low-odor recycled polypropylene composite material was obtained by melting, extrusion and granulation.

[0051] Example 5

[0052] This embodiment provides a low-odor recycled polypropylene composite material, and the preparation method includes the following steps:

[0053] Compared with Example 3, the components were added according to the ratio in Table 1, wherein the filler in Example 3 was replaced by barium sulfate and the lubricant was replaced by polyethylene wax. The remaining raw materials and preparation process were the same as in Example 3.

[0054] Example 6

[0055] This embodiment provides a low-odor recycled polypropylene composite material, and the preparation method includes the following steps:

[0056] Compared with Example 3, the components were added according to the ratio in Table 1, wherein the toughening agent in Example 3 was replaced by POE875L, the filler was replaced by wollastonite, and the lubricant was replaced by zinc stearate. The remaining raw materials and preparation process were the same as in Example 3.

[0057] Example 7

[0058] This embodiment provides a low-odor recycled polypropylene composite material, and the preparation method includes the following steps:

[0059] Compared with Example 3, the components were added according to the ratio in Table 1, wherein the toughening agent in Example 3 was replaced by POE875L, the filler was replaced by mica, and the lubricant was replaced by ethylene bis stearamide. The remaining raw materials and preparation process were the same as in Example 3.

[0060] Example 8

[0061] This embodiment provides a low-odor recycled polypropylene composite material, and the preparation method includes the following steps:

[0062] Compared with Example 3, each component is added according to the ratio in Table 1. The remaining raw materials and preparation process are the same as in Example 3.

[0063] Table 1 shows the added weight portions of each component in Examples 3 to 8.

[0064] Table 1

[0065]

[0066]

[0067] Comparative Example 1

[0068] This embodiment provides a low-odor recycled polypropylene composite material, and the preparation method includes the following steps:

[0069] Compared with Example 3, the components were added according to the ratios in Table 2, and the remaining raw materials and preparation process were the same as in Example 3.

[0070] Comparative Example 2

[0071] This embodiment provides a low-odor recycled polypropylene composite material, and the preparation method includes the following steps:

[0072] Compared with Example 3, the components were added according to the ratios in Table 2, and the remaining raw materials and preparation process were the same as in Example 3.

[0073] Comparative Example 3

[0074] This embodiment provides a low-odor recycled polypropylene composite material, and the preparation method includes the following steps:

[0075] Compared with Example 3, the components were added according to the ratios in Table 2, and the remaining raw materials and preparation process were the same as in Example 3.

[0076] Comparative Example 4

[0077] This embodiment provides a low-odor recycled polypropylene composite material, and the preparation method includes the following steps:

[0078] Compared with Example 3, the components were added according to the ratios in Table 2, and the remaining raw materials and preparation process were the same as in Example 3.

[0079] The components of Comparative Examples 1 to 4 in Table 2 were added in parts by weight.

[0080] Table 2

[0081]

[0082]

[0083] The low-odor recycled polypropylene composite materials prepared in Examples 3 to 8 and Comparative Examples 1 to 4 were tested for tensile strength, flexural strength, flexural modulus, and Izod notched impact strength according to the standard. The odor level test method was tested by referring to the German Volkswagen PV3900 test method. The specific method of the odor level test is as follows:

[0084] Place 20g of the above sample into a test vessel and put it into an oven for 2h. The temperature of the oven is set at (80±2)℃. The test vessel must be tightly sealed. After the test vessel is taken out of the oven, wait for it to cool to 60℃, slightly remove the lid, and have a professional odor assessor evaluate its odor. The odor level of the material is divided into the following standards: Level 1: no odor, Level 2: odor, but no disturbing odor, Level 3: obvious odor, but no disturbing odor, Level 4: disturbing odor, Level 5: strong disturbing odor, Level 6: unbearable odor.

[0085] The test results are shown in Tables 3 and 4.

[0086] Table 3

[0087]

[0088]

[0089] Table 4

[0090] Physical properties Test Standards Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Tensile strength MPa GB / T1040 17.4 18.3 16.7 16.5 Bending strength MPa GB / T9341 26.0 25.7 24.8 25.0 Flexural modulus MPa GB / T9341 1883 1903 1859 1842 <![CDATA[Izod impact strength KJ / m 2 > GB / T1843 14.1 14.7 12.8 13.2 Odor level Popular Standard 4.5 4.5 4 5.5

[0091] From the test results of Comparative Examples 3 and 4, it can be seen that the introduction of recycled polypropylene raw materials into the formula slightly reduces the basic mechanical properties of the prepared composite material, but the odor is significantly worse. The test results of Comparative Examples 1 and 2 show that the addition of a single component of MOFs material and TiO 2 Nanoparticles can also reduce the odor level, but the effect is limited. The test results of Examples 3 to 8 show that the increase in the total amount of odor inhibitor can significantly improve the odor situation. The final odor level reaches 3.5, which is better than the odor level of new materials, and has little effect on the basic mechanical properties of the parts. The best MOFs material and TiO 2 The ratio of nanoparticles is 2:1. From the above examples, it can be seen that MOFs materials and nano TiO 2 The volatile small molecules generated during extrusion and injection molding can be removed through the synergistic effect of adsorption and catalysis, which helps to prepare low-odor polypropylene composite materials, effectively promotes the recycling of waste polypropylene, and can be used in automotive interior and exterior trims.

[0092] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0093] 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.

Claims

1. A low-odor recycled polypropylene composite material, characterized in that: Including the following raw materials: PP resin, toughening agent, filler, antioxidant, lubricant, compatibilizer, odor inhibitor.

2. The low-odor recycled polypropylene composite material according to claim 1, characterized in that: The low-odor recycled polypropylene composite material comprises the following raw materials in parts by weight:

3. The low-odor recycled polypropylene composite material according to claim 1, characterized in that: The odor inhibitor is compounded by MOFs material and TiO2.

4. The low-odor recycled polypropylene composite material according to claim 3, characterized in that: The odor suppressor is compounded by MOFs material and TiO2 in a mass ratio of 1:0.5-2.

5. The low-odor recycled polypropylene composite material according to claim 3, characterized in that: The synthesis steps of the MOFs material are as follows: Add a zirconium source and benzoic acid to N,N-dimethylformamide, then add 1,3,6,8-tetrakis(4-carboxyphenyl)pyrene, transfer to a sealed container, heat to 110-120°C, maintain for 24-48 hours, centrifuge, wash, soak, centrifuge, and dry to obtain a MOFs material.

6. The low-odor recycled polypropylene composite material according to claim 3, characterized in that: The TiO2 is anatase TiO2 with a particle size of 50 to 100 nm.

7. The low-odor recycled polypropylene composite material according to claim 5, characterized in that: The zirconium source is ZrOCl2·8H2O or ZrCl4; the mass ratio of the zirconium source, benzoic acid, N,N-dimethylformamide and 1,3,6,8-tetrakis(4-carboxyphenyl)pyrene is 3:50:180:

1.

8. The low-odor recycled polypropylene composite material according to claim 1, characterized in that: The PP resin is a mixture of recycled polypropylene and copolymerized polypropylene.

9. A method for preparing the low-odor recycled polypropylene composite material according to any one of claims 1 to 8, characterized in that: The following steps are involved: PP resin, toughening agent, filler, antioxidant, lubricant compatibilizer and odor inhibitor are mixed and stirred to obtain a mixture; the mixture is put into a parallel twin-screw extruder for melting and extrusion granulation to obtain a low-odor recycled polypropylene composite material.

10. An application of the low-odor recycled polypropylene composite material according to any one of claims 1 to 8, characterized in that: Used in the preparation of automotive interior and exterior trims.

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