A polypropylene composition and a process for its preparation

Abstract

This invention discloses a polypropylene composition and its preparation method. The polypropylene composition is prepared from the following components in parts by weight: 100 parts polypropylene, 1-5 parts pigment, 0.1-2 parts coupling agent, and 0.1-2 parts antioxidant. The pigment in this invention contains 70-95 wt% nano-iron oxide red and 5-30 wt% titanium dioxide. When the average particle size of nano-iron oxide red is 50-100 nm and the average particle size of rutile titanium dioxide is 0.05-10 μm, it can have a high infrared reflectivity. When added to polypropylene material, after prolonged exposure to sunlight, it can not only prevent the surface temperature of polypropylene material from rising significantly but also significantly improve the tensile strength of the material.

Description

Technical Field

[0001] This invention belongs to the field of polymer materials technology, specifically relating to a polypropylene composition and its preparation method. Background Technology

[0002] Infrared radiation, one of the many invisible rays in sunlight, was discovered by the British scientist Herschel in 1800. Also known as infrared thermal radiation, it has a strong heating effect. He used a prism to separate sunlight and placed thermometers at various positions along different colored bands to measure the heating effect of different colors of light. He found that the thermometer located outside the red light band heated up the fastest. Therefore, he concluded that there must exist invisible rays outside the red light band in the solar spectrum—this is infrared radiation.

[0003] Infrared radiation can be divided into three parts: near-infrared radiation (high-frequency infrared radiation, with higher energy), with wavelengths between (3–2.5) μm and (1–0.75) μm; mid-infrared radiation (medium-frequency infrared radiation, with moderate energy), with wavelengths between (40–25) μm and (3–2.5) μm; and far-infrared radiation (low-frequency infrared radiation, with lower energy), with wavelengths between 1500 μm and (40–25) μm. Infrared radiation (especially near-infrared radiation) has a strong thermal effect. It can resonate with most inorganic molecules and organic macromolecules in living organisms, causing these molecules to accelerate their movement and rub against each other, thereby generating heat.

[0004] Polypropylene (PP), abbreviated as PP, is a colorless, odorless, non-toxic, and translucent solid. It is a high-performance thermoplastic synthetic resin, a colorless, translucent, lightweight, and general-purpose plastic. It possesses excellent chemical resistance, heat resistance, electrical insulation, high mechanical strength, and good abrasion resistance, which has led to its rapid development and widespread application in numerous fields since its invention, including machinery, automobiles, electronics, construction, textiles, packaging, agriculture, forestry, fisheries, and the food industry. In recent years, the rapid development of my country's packaging, electronics, and automotive industries has greatly promoted the country's industrial development. Furthermore, due to its plasticity, polypropylene materials are gradually replacing wood products, and its high strength, toughness, and abrasion resistance are gradually replacing the mechanical functions of metals. In addition, polypropylene has excellent grafting and composite properties, offering enormous application potential in concrete, textiles, packaging, and agriculture, forestry, and fisheries.

[0005] During the hot summer months, the surface temperature of polypropylene materials exposed to sunlight for extended periods can rise significantly, reaching 70-80°C. Such high temperatures are generally undesirable. Therefore, it is necessary to provide a pigment with high infrared reflectivity that, when added to polypropylene materials, can prevent the surface temperature from rising excessively. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the present invention aims to provide a polypropylene composition and its preparation method to solve the aforementioned problems.

[0007] The objective of this invention is achieved through the following technical solution:

[0008] A polypropylene composition, characterized in that it is prepared from the following components in parts by weight:

[0009]

[0010] The pigment comprises 70-95 wt% nano iron oxide red and 5-30 wt% titanium dioxide.

[0011] As a preferred technical solution, the nano-iron oxide red is semi-transparent with an average particle size of 50-100 nm.

[0012] As a preferred technical solution, the titanium dioxide is rutile titanium dioxide with an average particle size of 0.05-10μm.

[0013] As a preferred technical solution, the antioxidant is at least one of hindered phenolic antioxidants, hindered amine antioxidants, phosphite antioxidants, or thioester antioxidants. Further, the antioxidant is at least one of antioxidant 1010, antioxidant 1076, antioxidant 1098, antioxidant 626, antioxidant 300, antioxidant 1330, antioxidant 619F, or antioxidant 168.

[0014] As a preferred technical solution, the coupling agent is at least one selected from silane coupling agents, titanate coupling agents, and aluminate coupling agents. More preferably, the coupling agent is aluminate coupling agent LS-821.

[0015] The present invention also provides a method for preparing the polypropylene composition as described above, comprising the following steps:

[0016] (1) Add 100 parts of polypropylene, 1 to 5 parts of pigment, 0.1 to 2 parts of antioxidant, and 0.1 to 2 parts of coupling agent to a mixer and mix evenly to obtain a mixture.

[0017] (2) The mixture is added to a twin-screw extruder, and the final product is obtained by extrusion and pelletizing. Preferably, the temperature of the twin-screw extruder is 120-180℃ in zone one, 180-200℃ in zone two, 200-210℃ in zone three, 210-220℃ in zone four, 220-230℃ in zone five, and 220-230℃ in zone six.

[0018] Compared with the prior art, the beneficial effects of the present invention are reflected in:

[0019] The pigment in this invention contains 70-95% nano-iron oxide red and 5-30% titanium dioxide. When the average particle size of the nano-iron oxide red is 50-100 nm and the average particle size of the rutile titanium dioxide is 0.05-10 μm, it exhibits high infrared reflectivity. When added to polypropylene materials, after prolonged exposure to sunlight, it not only prevents a significant rise in the surface temperature of the polypropylene material but also significantly improves the tensile strength of the material. The aluminate coupling agent LS-821, when added to the polypropylene material, reduces the viscosity of the melt during the melting and mixing process, ensuring uniform dispersion of the nano-iron oxide red and titanium dioxide, resulting in superior performance. Detailed Implementation

[0020] The present invention will be further described below with reference to embodiments, so that those skilled in the art can better understand and implement the present invention, but the embodiments are not intended to limit the present invention.

[0021] In addition, unless otherwise specified, the preparation processes in the following embodiments are all conventional methods in the prior art, and therefore will not be described in detail; the parts in the following embodiments refer to parts by weight.

[0022] The specifications and suppliers of the products used in the following examples and comparative examples are as follows:

[0023] The polypropylene is S2040 produced by Shanghai SECCO Petrochemical Co., Ltd., which has a melt index of 36 g / 10 min and a tensile strength of 33 MPa under the conditions of 230℃ / 2.16Kg.

[0024] Nano iron oxide red is semi-transparent, with average particle sizes of 20nm, 80nm, 200nm, and 500nm. It is produced by BASF, Germany.

[0025] The titanium dioxide is rutile titanium dioxide with an average particle size of 1μm, produced by Ningbo Jiwei Nano New Materials Co., Ltd.

[0026] Silane coupling agent KH550, aluminate coupling agent LS-821, Jinan Baite New Materials Co., Ltd.

[0027] The reagents described above are only for illustrating the source and composition of the reagents used in the experiments of this invention, so as to provide full disclosure, and do not imply that the invention cannot be achieved by using other similar reagents or reagents provided by other suppliers.

[0028] Example 1

[0029] (1) Add 100 parts of polypropylene, 2.5 parts of pigment (83wt% nano iron oxide red, 17wt% titanium dioxide, average particle size of iron oxide red 80nm), 0.5 parts of antioxidant 1010 and 0.2 parts of aluminate coupling agent LS-821 to a mixer and mix evenly to obtain a mixture.

[0030] (2) The mixture is added to a twin-screw extruder, and the final product is obtained by extrusion and pelletizing. Further, the temperature of the twin-screw extruder is 140°C in zone one, 180°C in zone two, 200°C in zone three, 210°C in zone four, 220°C in zone five, and 220°C in zone six.

[0031] Example 2

[0032] (1) Add 100 parts of polypropylene, 4 parts of pigment (86 wt% nano iron oxide red, 14 wt% titanium dioxide, average particle size of iron oxide red 80 nm), 0.8 parts of antioxidant 1098, and 0.5 parts of aluminate coupling agent LS-821 to a mixer and mix evenly to obtain a mixture.

[0033] (2) The mixture is added to a twin-screw extruder, and the final product is obtained by extrusion and pelletizing. Further, the temperature of the twin-screw extruder is 160°C in zone one, 190°C in zone two, 200°C in zone three, 210°C in zone four, 220°C in zone five, and 230°C in zone six.

[0034] Example 3

[0035] (1) Add 100 parts of polypropylene, 3 parts of pigment (72wt% nano iron oxide red, 28wt% titanium dioxide, average particle size of iron oxide red 80nm), 0.6 parts of antioxidant 1098, and 0.8 parts of aluminate coupling agent LS-821 to a mixer and mix evenly to obtain a mixture.

[0036] (2) The mixture is added to a twin-screw extruder, and the final product is obtained by extrusion and pelletizing. Further, the temperature of the twin-screw extruder is 170°C in zone one, 180°C in zone two, 200°C in zone three, 220°C in zone four, 230°C in zone five, and 230°C in zone six.

[0037] Example 4

[0038] (1) Add 100 parts of polypropylene, 4.5 parts of pigment (91 wt% nano iron oxide red, 9 wt% titanium dioxide, average particle size of iron oxide red 80 nm), 1 part of antioxidant 1076 and 0.3 parts of aluminate coupling agent LS-821 to a mixer and mix evenly to obtain a mixture.

[0039] (2) The mixture is added to a twin-screw extruder, and the final product is obtained by extrusion and pelletizing. Further, the temperature of the twin-screw extruder is 160°C in zone one, 180°C in zone two, 200°C in zone three, 210°C in zone four, 220°C in zone five, and 220°C in zone six.

[0040] Example 5

[0041] (1) Add 100 parts of polypropylene, 3.5 parts of pigment (80wt% nano iron oxide red, 20wt% titanium dioxide, average particle size of iron oxide red 80nm), 0.8 parts of antioxidant 300 and 0.5 parts of aluminate coupling agent LS-821 to a mixer and mix evenly to obtain a mixture.

[0042] (2) The mixture is added to a twin-screw extruder, and the final product is obtained by extrusion and pelletizing. Further, the temperature of the twin-screw extruder is 180°C in zone one, 190°C in zone two, 200°C in zone three, 210°C in zone four, 220°C in zone five, and 230°C in zone six.

[0043] Example 6

[0044] (1) Add 100 parts of polypropylene, 3.5 parts of pigment (80wt% nano iron oxide red, 20wt% titanium dioxide, average particle size of iron oxide red 200nm), 0.8 parts of antioxidant 300, and 0.5 parts of aluminate coupling agent LS-821 to a mixer and mix evenly to obtain a mixture.

[0045] (2) The mixture is added to a twin-screw extruder, and the final product is obtained by extrusion and pelletizing. Further, the temperature of the twin-screw extruder is 180°C in zone one, 190°C in zone two, 200°C in zone three, 210°C in zone four, 220°C in zone five, and 230°C in zone six.

[0046] Example 7

[0047] (1) Add 100 parts of polypropylene, 3.5 parts of pigment (80wt% nano iron oxide red, 20wt% titanium dioxide, average particle size of iron oxide red 500nm), 0.8 parts of antioxidant 300, and 0.5 parts of aluminate coupling agent LS-821 to a mixer and mix evenly to obtain a mixture.

[0048] (2) The mixture is added to a twin-screw extruder, and the final product is obtained by extrusion and pelletizing. Further, the temperature of the twin-screw extruder is 180°C in zone one, 190°C in zone two, 200°C in zone three, 210°C in zone four, 220°C in zone five, and 230°C in zone six.

[0049] Example 8

[0050] (1) Add 100 parts of polypropylene, 3.5 parts of pigment (80wt% nano iron oxide red, 20wt% titanium dioxide, average particle size of iron oxide red 20nm), 0.8 parts of antioxidant 300 and 0.5 parts of aluminate coupling agent LS-821 to a mixer and mix evenly to obtain a mixture.

[0051] (2) The mixture is added to a twin-screw extruder, and the final product is obtained by extrusion and pelletizing. Further, the temperature of the twin-screw extruder is 180°C in zone one, 190°C in zone two, 200°C in zone three, 210°C in zone four, 220°C in zone five, and 230°C in zone six.

[0052] Example 9

[0053] (1) Add 100 parts of polypropylene, 3.5 parts of pigment (80wt% nano iron oxide red, 20wt% titanium dioxide, average particle size of iron oxide red 80nm), 0.8 parts of antioxidant 300 and 0.5 parts of silane coupling agent KH550 to a mixer and mix evenly to obtain a mixture.

[0054] (2) The mixture is added to a twin-screw extruder, and the final product is obtained by extrusion and pelletizing. Further, the temperature of the twin-screw extruder is 180°C in zone one, 190°C in zone two, 200°C in zone three, 210°C in zone four, 220°C in zone five, and 230°C in zone six.

[0055] Comparative Example 1 (compared to Example 5)

[0056] (1) Add 100 parts of polypropylene, 3.5 parts of pigment (100wt% nano iron oxide red, average particle size of iron oxide red 80nm), 0.8 parts of antioxidant 300 and 0.5 parts of aluminate coupling agent LS-821 to a mixer and mix evenly to obtain a mixture.

[0057] (2) The mixture is added to a twin-screw extruder, and the final product is obtained by extrusion and pelletizing. Further, the temperature of the twin-screw extruder is 180°C in zone one, 190°C in zone two, 200°C in zone three, 210°C in zone four, 220°C in zone five, and 230°C in zone six.

[0058] Comparative Example 2 (compared to Example 5)

[0059] (1) Add 100 parts of polypropylene, 3.5 parts of pigment (100wt% titanium dioxide), 0.8 parts of antioxidant 300, and 0.5 parts of aluminate coupling agent LS-821 to a mixer and mix evenly to obtain a mixture.

[0060] (2) The mixture is added to a twin-screw extruder, and the final product is obtained by extrusion and pelletizing. Further, the temperature of the twin-screw extruder is 180°C in zone one, 190°C in zone two, 200°C in zone three, 210°C in zone four, 220°C in zone five, and 230°C in zone six.

[0061] Comparative Example 3 (compared to Example 5)

[0062] (1) Add 100 parts of polypropylene, 8 parts of pigment (80wt% nano iron oxide red, 20wt% titanium dioxide, average particle size of iron oxide red 80nm), 0.8 parts of antioxidant 300 and 0.5 parts of aluminate coupling agent LS-821 to a mixer and mix evenly to obtain a mixture.

[0063] (2) The mixture is added to a twin-screw extruder, and the final product is obtained by extrusion and pelletizing. Further, the temperature of the twin-screw extruder is 180°C in zone one, 190°C in zone two, 200°C in zone three, 210°C in zone four, 220°C in zone five, and 230°C in zone six.

[0064] Comparative Example 4 (compared to Example 5)

[0065] (1) Add 100 parts of polypropylene, 3.5 parts of carbon black (average particle size 1μm), 0.8 parts of antioxidant 300 and 0.5 parts of aluminate coupling agent LS-821 to a mixer and mix evenly to obtain a mixture.

[0066] (2) The mixture is added to a twin-screw extruder, and the final product is obtained by extrusion and pelletizing. Further, the temperature of the twin-screw extruder is 180°C in zone one, 190°C in zone two, 200°C in zone three, 210°C in zone four, 220°C in zone five, and 230°C in zone six.

[0067] Comparative Example 5 (compared to Example 5)

[0068] (1) Add 100 parts of polypropylene, 3.5 parts of pigment (80wt% nano iron oxide red, 20wt% carbon black, with an average particle size of 80nm for iron oxide red and 1μm for carbon black), 0.8 parts of antioxidant 300, and 0.5 parts of aluminate coupling agent LS-821 to a mixer and mix evenly to obtain a mixture.

[0069] (2) The mixture is added to a twin-screw extruder, and the final product is obtained by extrusion and pelletizing. Further, the temperature of the twin-screw extruder is 180°C in zone one, 190°C in zone two, 200°C in zone three, 210°C in zone four, 220°C in zone five, and 230°C in zone six.

[0070] Comparative Example 6 (compared to Example 5)

[0071] (1) Add 100 parts of polypropylene, 3.5 parts of iron oxide yellow (average particle size 80nm), 0.8 parts of antioxidant 300 and 0.5 parts of aluminate coupling agent LS-821 to a mixer and mix evenly to obtain a mixture.

[0072] (2) The mixture is added to a twin-screw extruder, and the final product is obtained by extrusion and pelletizing. Further, the temperature of the twin-screw extruder is 180°C in zone one, 190°C in zone two, 200°C in zone three, 210°C in zone four, 220°C in zone five, and 230°C in zone six.

[0073] Performance testing

[0074] The products prepared in each embodiment and comparative example were tested for relevant properties according to the following methods:

[0075] Tensile strength test: Prepare the product into a tensile specimen, (170.0±5.0)mm*(13.0±0.5)mm*(3.2±0.2)mm, with a tensile rate of 5mm / min; the tensile strength test shall be conducted in accordance with GB / T 1040.

[0076] Near-infrared reflectance test: The test shall be conducted in accordance with the standard GB / T 25261-2018, wherein the near-infrared reflectance is the ratio of the reflected solar radiation energy flux in the 780nm-2500nm near-infrared band to the incident solar radiation energy flux.

[0077] The standard for testing the surface temperature of the material is room temperature of 23℃, relative humidity of 50%, and irradiation with an infrared lamp for 30 minutes at a distance of 40cm.

[0078] The performance test results are shown in Table 1.

[0079] Table 1. Performance test results of the products obtained in each embodiment and comparative example.

[0080]

[0081]

[0082] Based on the test results, the pigment in this invention contains 70-95 wt% nano-iron oxide red and 5-30 wt% titanium dioxide. When the average particle size of nano-iron oxide red is 80 nm and the average particle size of rutile titanium dioxide is 1 μm, it can have a high infrared reflectivity. When added to polypropylene material, it can prevent the surface temperature of polypropylene material from rising significantly after prolonged exposure to sunlight.

[0083] When the particle size of iron oxide red is reduced to 20nm, its tensile strength becomes more excellent when added to polypropylene material. However, due to the small particle size, the light reflectivity of polypropylene material is significantly reduced.

[0084] When the particle size of iron oxide red increases to 200nm and 500nm, its tensile strength continuously deteriorates when added to polypropylene materials, and the light reflectivity of polypropylene materials continuously decreases.

[0085] Using iron oxide red, titanium dioxide, carbon black, and iron oxide yellow alone results in poor near-infrared emissivity of polypropylene materials; even by compounding iron oxide red and carbon black, the near-infrared reflectivity of polypropylene materials still does not show good technical improvement.

[0086] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent modifications made using the present invention are within the patent protection scope of the present invention.

Claims

1. A polypropylene composition, characterized in that: It is prepared from the following components in parts by weight: 100 parts of polypropylene 1-5 parts pigment 0.1-2 parts of coupling agent, Antioxidant 0.1-2 parts; The pigment comprises 70-95 wt% nano iron oxide red and 5-30 wt% titanium dioxide. The nano-iron oxide red is semi-transparent with an average particle size of 50-100 nm. The titanium dioxide is rutile titanium dioxide with an average particle size of 0.05-10µm; The coupling agent is aluminate coupling agent LS-821.

2. The polypropylene composition according to claim 1, characterized in that: The antioxidant is at least one of hindered phenolic antioxidants, hindered amine antioxidants, phosphite antioxidants, or thioester antioxidants.

3. The polypropylene composition according to claim 2, characterized in that: The antioxidant is at least one of antioxidant 1010, antioxidant 1076, antioxidant 1098, antioxidant 626, antioxidant 300, antioxidant 1330, antioxidant 619F, or antioxidant 168.

4. The method for preparing the polypropylene composition according to any one of claims 1 to 3, characterized in that: Includes the following steps: (1) Add 100 parts of polypropylene, 1 to 5 parts of pigment, 0.1 to 2 parts of antioxidant, and 0.1 to 2 parts of coupling agent to a mixer and mix evenly to obtain a mixture. (2) Add the mixture into a twin-screw extruder, and after extrusion and pelletizing, the final product is obtained.

5. The method for preparing the polypropylene composition according to claim 4, characterized in that: The temperature of the twin-screw extruder is 120-180℃ in zone one, 180-200℃ in zone two, 200-210℃ in zone three, 210-220℃ in zone four, 220-230℃ in zone five, and 220-230℃ in zone six.

Images