Low-density high-performance modified polypropylene material as well as preparation method and application thereof

Abstract

The invention discloses a modified polypropylene material with low density and high performance. The invention discloses a modified polypropylene material, which is prepared from the following components in parts by mass: 82 to 97 parts of polypropylene, 2 to 6 parts of polyolefin elastomer POE, 0 to 5 parts of compatilizer, 0 to 5 parts of reinforcing filler, 0.1 to 0.3 part of antioxidant and 0 to 0.7 part of nucleating agent. The invention also discloses a preparation method of the modified polypropylene material and application of the modified polypropylene material as an automobile part. The high-performance modified polypropylene material prepared by adopting the high-fluidity co-polypropylene as a base material, the polyolefin elastomer POE as a toughening component and the impact-resistant polypropylene as an auxiliary toughening component and selecting talcum powder with different particle sizes to be compounded as a reinforcing filler has the characteristics of low density, high fluidity, high impact resistance and high modulus; the invention relates to the field of automobile parts.

Description

Technical Field

[0001] The invention relates to the technical field of polypropylene modification, and in particular to a low-density, high-performance modified polypropylene material and a preparation method and application thereof. Background Art

[0002] With the development of economy and the continuous improvement of people's living standards, the demand for automobiles in my country is maintaining steady growth. Studies have shown that for every 10% reduction in the vehicle's deadweight, fuel consumption per 100 kilometers can be reduced by 6%-8% and emissions by 4%. The development of lightweight automobiles is one of the effective ways to save energy and reduce emissions, and is the trend and development trend of the automobile industry.

[0003] Polypropylene has the advantages of low density, excellent mechanical properties, good chemical stability, easy processing and low cost. It is widely used in various industries, especially in the automotive field. Polypropylene is used in many parts such as car bumpers, dashboards, door panels, air conditioner shells, etc. Lightweight high-performance modified polypropylene materials maintain excellent properties such as high fluidity, high toughness and high modulus to meet the thin-wall and lightweight requirements of automotive plastic parts under the premise of lower density, which has great social and economic benefits in promoting the localization of automotive materials.

[0004] Patent CN106366454B discloses a modified polypropylene material for high-performance thin-walled automobile door panels and its preparation method. It uses a variety of polypropylene compounds, uses POE elastomers for toughening, mineral reinforcing agents for stiffening, and high-flow propylene-based elastomers as melt index regulators to increase fluidity, and prepares a polypropylene material with "three highs" of high fluidity, high rigidity, and high toughness for thin-walled automobile door panels. However, the content of the mineral reinforcing agent used in the invention is as high as 20%-25%, resulting in a material density greater than 1g / cm 3 , the material density is relatively high.

[0005] Patent CN110835443A discloses a lightweight modified polypropylene material and its preparation method and application in automobile pillar guard plates. The invention uses highly crystalline and highly fluid copolymer polypropylene as the base material, adds a relatively low content of inorganic filler, and prepares a low-density modified polypropylene material with sufficient rigidity and toughness, but does not provide the material flow performance data.

[0006] Patent CN113563667A discloses a lightweight modified polypropylene composite material for compounding and filling bumpers and its preparation method. The composite material uses glass microspheres and talcum powder as fillers to prepare polypropylene composite materials with high modulus, high impact and low shrinkage. However, the total filler content of glass microspheres and talcum powder is 10%, and the material density is high (0.98g / cm 3 ), and the melt flow rate of the material is 22-24g / 10min, and the fluidity needs to be improved. Summary of the invention

[0007] In view of the deficiencies of the prior art, the object of the present invention is to provide a low-density, high-performance modified polypropylene material and its preparation method and application. The present invention adopts high-fluidity copolymerized polypropylene with a melt index of 50-100g / 10min as a base material, polyolefin elastomer POE as a toughening component, impact-resistant polypropylene as an auxiliary toughening component, and selects talcum powder of different particle sizes as a reinforcing filler. The prepared high-performance modified polypropylene material has the characteristics of low density, high fluidity, high impact resistance and high modulus, and is suitable for application in the field of automotive parts.

[0008] To this end, in a first aspect, the present invention provides a low-density, high-performance modified polypropylene material, which comprises, by weight:

[0009] Polypropylene 82-97 parts;

[0010] Polyolefin elastomer POE 2-6 parts;

[0011] Reinforcing filler 0-5 parts, and contains 0, preferably 0.1-5 parts;

[0012] Compatibilizer 0-5 parts, and including 0, preferably 0.1-5 parts;

[0013] Antioxidant 0.1-0.3 parts;

[0014] Nucleating agent 0-0.7 parts, and including 0, preferably 0.1-0.7 parts;

[0015] Wherein, the polypropylene includes copolymer polypropylene and impact-resistant polypropylene.

[0016] As a specific embodiment of the present invention, preferably, according to GB / T 3682.1-2018 standard, the melt index of the modified polypropylene is greater than or equal to 40g / 10min at 230°C and 2.16Kg; according to GB / T1843-2008 standard, the Izod notched impact strength is greater than 25kJ / m 2 According to GB / T 9341-2008 standard, the bending modulus is greater than 1500MPa; the density of the modified polypropylene is 0.92-0.95g / cm 3 .

[0017] As a specific embodiment of the present invention, preferably, according to GB / T 3682.1-2018 standard, the melt index of the copolymerized polypropylene is 50-100 g / 10 min at 230°C and 2.16 kg; and / or the comonomer of the copolymerized polypropylene is ethylene, and the ethylene content is 5-15%; and / or the melt index of the impact-resistant polypropylene is 10-40 g / 10 min at 230°C and 2.16 kg; and / or the impact-resistant polypropylene is a copolymerized polypropylene, and the content of the comonomer ethylene is 8-16%; and / or the polypropylene comprises 77-82 parts of the copolymerized polypropylene and 5-15 parts of the impact-resistant polypropylene in parts by mass.

[0018] As a specific embodiment of the present invention, preferably, according to GB / T 3682.1-2018 standard, the melt index of the polyolefin elastomer POE is 1-10 g / 10 min at 230° C. and 2.16 kg; preferably, the polyolefin elastomer POE is an ethylene-octene copolymer.

[0019] As a specific embodiment of the present invention, preferably, the reinforcing filler comprises at least two talc powders with different particle sizes. Further preferably, the particle size of the talc powder is 2500-10000 mesh. Further preferably, the two particle sizes of the talc powder are 2500-3500 mesh and 4500-5500 mesh respectively.

[0020] As a specific embodiment of the present invention, preferably, the compatibilizer is maleic anhydride grafted polypropylene.

[0021] As a specific embodiment of the present invention, preferably, the antioxidant is selected from one or more of antioxidant 168, antioxidant 1010, and antioxidant 3114.

[0022] As a specific embodiment of the present invention, preferably, the nucleating agent is a carboxylic acid metal salt, preferably, the nucleating agent is HPN-20E.

[0023] To this end, in a second aspect, the present invention provides a method for preparing the above-mentioned low-density, high-performance modified polypropylene material, comprising the following steps: mixing the components evenly and then extruding and granulating them; preferably, the mixing is carried out in a high-speed mixer, and / or the extrusion granulation is carried out in a twin-screw extruder.

[0024] As a specific embodiment of the present invention, preferably, the processing temperature of the twin-screw extruder is 145-210°C, and the screw speed is 180-220r / min; specifically, the processing temperature of the twin-screw extruder from the die head to the feeding section is set to 195°C, 210°C, 210°C, 205°C, 200°C, 190°C, 180°C, 160°C, and 145°C, respectively, that is, the processing temperature is 145-210°C.

[0025] As a specific embodiment of the present invention, preferably, the extrusion granulation comprises the following steps: melting, extrusion, cooling, stranding and pelletizing.

[0026] To this end, in a third aspect, the present invention provides a use of the above-mentioned low-density, high-performance modified polypropylene material as automotive parts.

[0027] The advantages of the present invention are:

[0028] The modified polypropylene material disclosed in the present invention has the advantages of high modulus, high impact strength and good fluidity while ensuring that the polypropylene has a relatively low density. According to the GB / T 3682.1-2018 standard, the melt index of the low-density modified polypropylene material is greater than or equal to 40g / 10min at 230°C and 2.16Kg. According to the GB / T1843-2008 standard, the cantilever beam notched impact strength of the low-density high-performance modified polypropylene material is greater than 25kJ / m 2 According to GB / T 9341-2008 standard, the bending modulus of the low-density, high-performance modified polypropylene material is greater than 1500MPa. Low-density and high-performance polypropylene materials are suitable for the lightweight and thin-wall development of automotive plastics, which is of great significance to automobile energy conservation and emission reduction. DETAILED DESCRIPTION

[0029] The present invention will be further described below in conjunction with specific embodiments, but they do not constitute any limitation to the present invention.

[0030] In the following examples and comparative examples, according to GB / T According to the 3682.1-2018 standard, the melt index of copolymerized polypropylene is 50g / 10min at 230°C and 2.16Kg, the comonomer is ethylene, and the ethylene content is 8%; the melt index of impact-resistant polypropylene is 30g / 10min at 230°C and 2.16Kg, the impact-resistant polypropylene is copolymerized polypropylene, and the ethylene content of the comonomer is 10%; the polyolefin elastomer POE is ethylene-octene copolymer, and its melt index is 4g / 10min at 230°C and 2.16Kg; the talcum powder particle size is 3000 mesh and 5000 mesh, purchased from Changzhou Mingfeng Powder Raw Material Co., Ltd.; the compatibilizer is maleic anhydride grafted polypropylene, purchased from Shanghai Jiuju Polymer Materials Co., Ltd.; the antioxidants are antioxidant 168 and antioxidant 1010 (mass ratio is 1:1), purchased from Dow Chemical; the nucleating agent is HPN-20E, a product of Milliken & Company.

[0031] Example 1

[0032] The low-density, high-performance modified polypropylene material provided in this embodiment includes, by weight, 82 parts of copolymerized polypropylene, 6 parts of impact-resistant polypropylene, 6 parts of polyolefin elastomer POE, 3 parts of 3000-mesh talc powder and 2 parts of 5000-mesh talc powder, 0.7 parts of nucleating agent, and 0.3 parts of antioxidant.

[0033] The preparation method is as follows: the raw materials are pre-mixed uniformly in a high-speed mixer, added to a twin-screw extruder for extrusion granulation, and a low-density, high-performance modified polypropylene material is prepared. The processing temperature of the twin-screw extruder is set to 195°C, 210°C, 210°C, 205°C, 200°C, 190°C, 180°C, 160°C, and 145°C from the die head to the feeding section, and the screw speed is 200r / min. The prepared low-density, high-performance modified polypropylene material is injection molded to obtain a standard specimen for testing, and the injection molding temperatures from the nozzle to the feeding are 210°C, 200°C, 180°C, and 120°C, respectively, the injection molding pressure is 65MPa, and the holding pressure is 45MPa.

[0034] Example 2

[0035] The low-density, high-performance modified polypropylene material provided in this embodiment includes, by weight, 81.2 parts of copolymerized polypropylene, 5 parts of impact-resistant polypropylene, 3 parts of polyolefin elastomer POE, 5 parts of compatibilizer, 1.5 parts of 3000-mesh talc and 1.5 parts of 5000-mesh talc, 0.5 parts of nucleating agent, and 0.3 parts of antioxidant.

[0036] The preparation method is as follows: the raw materials are pre-mixed uniformly in a high-speed mixer, added to a twin-screw extruder, extruded and granulated to prepare a low-density, high-performance modified polypropylene material. The processing temperature of the twin-screw extruder is set to 195°C, 210°C, 210°C, 205°C, 200°C, 190°C, 180°C, 160°C, and 145°C from the die head to the feeding section, and the screw speed is 200r / min. The prepared low-density, high-performance modified polypropylene material is injection molded to obtain a standard specimen for testing, and the injection molding temperatures from the nozzle to the feeding are 210°C, 200°C, 180°C, and 120°C, respectively, the injection molding pressure is 65MPa, and the holding pressure is 45MPa.

[0037] Example 3

[0038] The low-density, high-performance modified polypropylene material provided in this embodiment includes, by weight, 81.2 parts of copolymerized polypropylene, 10 parts of impact-resistant polypropylene, 3 parts of polyolefin elastomer POE, 1.5 parts of 3000-mesh talc powder and 1.5 parts of 5000-mesh talc powder, 0.5 parts of a nucleating agent, and 0.3 parts of an antioxidant.

[0039] The preparation method is as follows: the raw materials are pre-mixed uniformly in a high-speed mixer, added to a twin-screw extruder, extruded and granulated to prepare a low-density, high-performance modified polypropylene material. The processing temperature of the twin-screw extruder is set to 195°C, 210°C, 210°C, 205°C, 200°C, 190°C, 180°C, 160°C, and 145°C from the die head to the feeding section, and the screw speed is 200r / min. The prepared low-density, high-performance modified polypropylene material is injection molded to obtain a standard specimen for testing, and the injection molding temperatures from the nozzle to the feeding are 210°C, 200°C, 180°C, and 120°C, respectively, the injection molding pressure is 65MPa, and the holding pressure is 45MPa.

[0040] Example 4

[0041] The low-density, high-performance modified polypropylene material provided in this embodiment includes, by weight, 77.2 parts of copolymerized polypropylene, 15 parts of impact-resistant polypropylene, 2 parts of polyolefin elastomer POE, 2.5 parts of 3000-mesh talc powder and 2.5 parts of 5000-mesh talc powder, 0.5 parts of a nucleating agent, and 0.3 parts of an antioxidant.

[0042] The preparation method is as follows: the raw materials are pre-mixed uniformly in a high-speed mixer, added to a twin-screw extruder, extruded and granulated to prepare a low-density, high-performance modified polypropylene material. The processing temperature of the twin-screw extruder is set to 195°C, 210°C, 210°C, 205°C, 200°C, 190°C, 180°C, 160°C, and 145°C from the die head to the feeding section, and the screw speed is 200r / min. The prepared low-density, high-performance modified polypropylene material is injection molded to obtain a standard specimen for testing, and the injection molding temperatures from the nozzle to the feeding are 210°C, 200°C, 180°C, and 120°C, respectively, the injection molding pressure is 65MPa, and the holding pressure is 45MPa.

[0043] Comparative Example 1

[0044] The modified polypropylene material provided in this comparative example comprises, by weight, 82.7 parts of copolymerized polypropylene, 7 parts of impact-resistant polypropylene, 5 parts of polyolefin elastomer POE, 2.5 parts of 3000-mesh talc powder and 2.5 parts of 5000-mesh talc powder, and 0.3 parts of an antioxidant.

[0045] The preparation method is as follows: the raw materials are pre-mixed uniformly in a high-speed mixer, added to a twin-screw extruder, extruded and granulated to prepare a low-density, high-performance modified polypropylene material. The processing temperature of the twin-screw extruder is set to 195°C, 210°C, 210°C, 205°C, 200°C, 190°C, 180°C, 160°C, and 145°C from the die head to the feeding section, and the screw speed is 200r / min. The prepared low-density, high-performance modified polypropylene material is injection molded to obtain a standard specimen for testing, and the injection molding temperatures from the nozzle to the feeding are 210°C, 200°C, 180°C, and 120°C, respectively, the injection molding pressure is 65MPa, and the holding pressure is 45MPa.

[0046] Comparative Example 2

[0047] The modified polypropylene material provided in this comparative example comprises, by weight, 94.2 parts of copolymerized polypropylene, 5 parts of 5000 mesh talc, 0.5 parts of nucleating agent, and 0.3 parts of antioxidant.

[0048] The preparation method is as follows: the raw materials are pre-mixed uniformly in a high-speed mixer, added to a twin-screw extruder, extruded and granulated to prepare a low-density, high-performance modified polypropylene material. The processing temperature of the twin-screw extruder is set to 195°C, 210°C, 210°C, 205°C, 200°C, 190°C, 180°C, 160°C, and 145°C from the die head to the feeding section, and the screw speed is 200r / min. The prepared low-density, high-performance modified polypropylene material is injection molded to obtain a standard specimen for testing, and the injection molding temperatures from the nozzle to the feeding are 210°C, 200°C, 180°C, and 120°C, respectively, the injection molding pressure is 65MPa, and the holding pressure is 45MPa.

[0049] Comparative Example 3

[0050] The modified polypropylene material provided in this comparative example comprises, by weight, 94.7 parts of impact-resistant polypropylene, 5 parts of 5000-mesh talc, and 0.3 parts of an antioxidant.

[0051] The preparation method is as follows: the raw materials are pre-mixed uniformly in a high-speed mixer, added to a twin-screw extruder, extruded and granulated to prepare a low-density, high-performance modified polypropylene material. The processing temperature of the twin-screw extruder is set to 195°C, 210°C, 210°C, 205°C, 200°C, 190°C, 180°C, 160°C, and 145°C from the die head to the feeding section, and the screw speed is 200r / min. The prepared low-density, high-performance modified polypropylene material is injection molded to obtain a standard specimen for testing, and the injection molding temperatures from the nozzle to the feeding are 210°C, 200°C, 180°C, and 120°C, respectively, the injection molding pressure is 65MPa, and the holding pressure is 45MPa.

[0052] In the above embodiments and comparative examples, the performance test standards and conditions of the modified polypropylene material are as follows:

[0053] Tensile performance test: According to GB / T 1040-2006 standard, the prepared specimens were subjected to a tensile test at a tensile speed of 20 mm / min.

[0054] Bending performance test: According to GB / T 9341-2008 standard, the prepared specimens were subjected to a bending test.

[0055] Izod notched impact test: The impact performance test was performed on the prepared standard impact specimens according to GB / T 1843-2008.

[0056] Melt index test: The melt flow rate of the prepared material is tested at 230°C and 2.16 kg load according to GB / T 3682.1-2018.

[0057] Density test: The density of the test specimen is tested according to GB / T 1033.1-2008.

[0058] The test results are shown in Table 1.

[0059] Table 1 Properties of modified polypropylene materials in various examples

[0060]

[0061] It can be seen from the test results in Table 1 that the present invention uses high-flow copolymer polypropylene as the base material, POE as the toughening agent, impact-resistant polypropylene as the auxiliary toughening component, a small amount of inorganic filler and nucleating agent, and the prepared high-performance modified polypropylene material has a density of 0.92-0.95 g / cm3 The melt index is greater than or equal to 40g / 10min at 230℃ and 2.16Kg, and the Izod notched impact strength is greater than 25kJ / m 2 , the bending modulus is greater than 1500MPa. High-performance modified polypropylene material has the characteristics of low density, high fluidity, high impact resistance and high modulus, and is suitable for the field of automotive parts.

[0062] Any numerical value mentioned in the present invention, if there is only an interval of two units between any minimum value and any maximum value, includes all values ​​from the minimum value to the maximum value each time increasing by one unit. For example, if the amount of a component, or the value of a process variable such as temperature, pressure, time, etc. is declared to be 50-90, in this specification it means that 51-89, 52-88... and 69-71 and 70-71 are specifically listed. For non-integer values, 0.1, 0.01, 0.001 or 0.0001 can be appropriately considered as a unit. These are just some specially specified examples. In this application, in a similar manner, all possible combinations of numerical values ​​between the listed minimum and maximum values ​​are considered to have been disclosed.

[0063] It should be noted that the embodiments described above are only used to explain the present invention and do not constitute any limitation to the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory words, rather than restrictive words. The present invention may be modified as specified within the scope of the claims of the present invention, and the present invention may be revised without departing from the scope and spirit of the present invention. Although the present invention described therein relates to specific methods, materials and embodiments, it does not mean that the present invention is limited to the specific examples disclosed therein, on the contrary, the present invention can be extended to all other methods and applications with the same functions.

Claims

1. A low-density, high-performance modified polypropylene material, characterized in that: Calculated by mass, including: Polypropylene 82-97 parts; Polyolefin elastomer POE 2-6 parts; Reinforcing filler 0-5 parts, and contains 0, preferably 0.1-5 parts; Compatibilizer 0-5 parts, and including 0, preferably 0.1-5 parts; Antioxidant 0.1-0.3 parts; Nucleating agent 0-0.7 parts, and including 0, preferably 0.1-0.7 parts; Wherein, the polypropylene includes copolymer polypropylene and impact-resistant polypropylene.

2. The modified polypropylene material according to claim 1, characterized in that: According to GB / T3682.1-2018 standard, the melt index of the modified polypropylene is greater than or equal to 40g / 10min at 230°C and 2.16Kg; according to GB / T 1843-2008 standard, the cantilever beam notched impact strength is greater than 25kJ / m 2 According to GB / T 9341-2008 standard, the bending modulus is greater than 1500MPa; the density of the modified polypropylene is 0.92-0.95g / cm 3 .

3. The modified polypropylene material according to claim 1 or 2, characterized in that: According to GB / T3682.1-2018 standard, the melt index of the copolymerized polypropylene is 50-100 g / 10 min at 230°C and 2.16 kg; and / or the comonomer of the copolymerized polypropylene is ethylene, and the ethylene content is 5-15%; and / or the melt index of the impact-resistant polypropylene is 10-40 g / 10 min at 230°C and 2.16 kg; and / or the impact-resistant polypropylene is a copolymerized polypropylene, and the content of the comonomer ethylene is 8-16%; and / or the polypropylene includes 77-82 parts of the copolymerized polypropylene and 5-15 parts of the impact-resistant polypropylene in parts by mass.

4. The modified polypropylene material according to any one of claims 1 to 3, characterized in that: According to GB / T3682.1-2018 standard, the melt index of the polyolefin elastomer POE is 1-10 g / 10 min at 230° C. and 2.16 kg; preferably, the polyolefin elastomer POE is an ethylene-octene copolymer.

5. The modified polypropylene material according to any one of claims 1 to 4, characterized in that: The reinforcing filler comprises at least two kinds of talc powder with different particle sizes. Preferably, the particle size of the talc powder is 2500-10000 mesh. Preferably, the two particle sizes of the talc powder are 2500-3500 mesh and 4500-5500 mesh respectively.

6. The modified polypropylene material according to any one of claims 1 to 5, characterized in that: The compatibilizer is maleic anhydride grafted polypropylene.

7. The modified polypropylene material according to any one of claims 1 to 6, characterized in that: The antioxidant is selected from one or more of antioxidant 168, antioxidant 1010, and antioxidant 3114.

8. The modified polypropylene material according to any one of claims 1 to 7, characterized in that: The nucleating agent is a carboxylic acid metal salt, and preferably, the nucleating agent is HPN-20E.

9. A method for preparing a low-density, high-performance modified polypropylene material according to any one of claims 1 to 8, characterized in that: The following steps are involved: The components are mixed uniformly and then extruded into granules; preferably, the mixing is carried out in a high-speed mixer, and / or the extrusion granulation is carried out in a twin-screw extruder.

10. The preparation method according to claim 9, characterized in that: The processing temperature of the twin-screw extruder is 145-210° C., and the screw speed is 180-220 r / min.

11. Use of the low-density, high-performance modified polypropylene material according to any one of claims 1 to 8 as automotive parts.

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