Propylene-butylene co-polypropylene composition, propylene-butylene co-polypropylene material and preparation method and application thereof

Abstract

The invention relates to the field of polypropylene materials, in particular to a polypropylene-propylene-butylene copolymer composition, a polypropylene-propylene-butylene copolymer material and a preparation method and application of the polypropylene-propylene-butylene copolymer composition and the polypropylene-propylene-butylene copolymer material. The composition comprises polypropylene-propylene-butylene copolymer resin, polybutylene, an antioxidant, a halogen absorbent and a nucleating agent; the polypropylene-butylene copolymer material prepared from the polypropylene composition with specific components has excellent mechanical properties, optical properties and heat resistance.

Description

Technical Field

[0001] The invention relates to the field of polypropylene materials, and in particular to a propylene-butane copolymerized polypropylene composition, a propylene-butane copolymerized polypropylene material, and a preparation method and application thereof. Background Art

[0002] Thermoforming is a typical secondary molding technology for plastic processing, that is, using pressure (positive pressure or vacuum negative pressure) to fit the heated and softened thermoplastic plastic plates and sheets to the mold surface, and after cooling and shaping, various semi-enclosed products are made through simple trimming. Thermoforming processing has the advantages of short molding cycle, high efficiency and high degree of automation. The plastic raw materials for thermoforming are mainly thermoplastic plastics, such as general plastics such as polypropylene (PP), polyethylene (PE), polyvinyl chloride (PVC) and polystyrene (PS) and engineering plastics such as polycarbonate (PC) and acrylonitrile-butadiene-styrene copolymer (ABS). Compared with other plastics, PP has outstanding advantages such as light weight, low price, non-toxicity, good transparency, good rigidity and toughness balance, and good heat resistance. Therefore, it has broad application prospects and development advantages in the field of thermoforming, especially in the field of thermoforming food packaging. At present, PP thermoforming products are mainly concentrated in mid-to-high-end plastic packaging products, such as plastic cups, plastic lids, heat-resistant lunch boxes, etc.

[0003] According to research, many thermoforming manufacturers usually use homopolymer PP as the raw material for thermoforming products, among which the most widely used PP grade is T30S. Although the rigidity of homopolymer PP material meets the requirements, its transparency is limited and its mechanical properties are also poor. Therefore, it cannot be used in the production of mid-to-high-end thermoforming packaging products that have higher requirements for product transparency and mechanical properties. In order to develop PP raw materials suitable for such products, downstream manufacturers generally use the method of adding clarifiers and polyolefin elastomers (POE) to homopolymer PP resins to perform physical blending modification, thereby improving the transparency and flexibility of the products.

[0004] However, this method often leads to unstable product quality (such as poor product transparency, reduced rigidity and uneven wall thickness) and low production efficiency due to uneven blending. Therefore, thermoforming manufacturers producing mid-to-high-end plastic packaging products are in urgent need of more suitable polypropylene raw materials to adapt to existing thermoforming equipment and processes and meet the material's requirements for processing performance, mechanical properties and transparency.

[0005] Currently, many thermoformable polypropylene materials have problems such as insufficient rigidity or transparency.

[0006] CN105754232A discloses a heat-resistant, high-rigidity, high-toughness, transparent thermoforming polypropylene material and its preparation process. The process uses ethylene-propylene binary copolymer polypropylene resin as a base material, and prepares a thermoforming polypropylene resin by adding an antioxidant, an acid absorber and a nucleating agent. The polypropylene resin prepared by this method achieves a good balance of rigidity and toughness, which can meet the needs of some thermoforming polypropylene markets, but its transparency (haze 28%-38%) and heat resistance (heat deformation temperature 88-96°C) are slightly insufficient, and cannot meet the requirements of thermoforming products with high transparency and heat resistance. Summary of the invention

[0007] The purpose of the present invention is to overcome the problem that polypropylene in the prior art cannot take into account mechanical properties, optical properties and heat resistance at the same time, and to provide a polypropylene composition and a preparation method and application thereof. The specific components in the composition enable a propylene-butane copolymer polypropylene material prepared from the composition to have excellent mechanical properties, optical properties and heat resistance at the same time.

[0008] In order to achieve the above object, the first aspect of the present invention provides a polypropylene composition, wherein the composition comprises: propylene-butene copolymer polypropylene resin, polybutene, an antioxidant, a halogen absorber and a nucleating agent.

[0009] The second aspect of the present invention provides a method for preparing a propylene-butyl copolymer polypropylene material, wherein the preparation method comprises the following steps:

[0010] (1) adding propylene and 1-butene in the presence of a catalyst to carry out polymerization reaction to obtain a propylene-butene copolymer polypropylene resin;

[0011] (2) The propylene-butene copolymerized polypropylene resin, polybutene, an antioxidant, a halogen absorber and a nucleating agent are mixed and melt-extruded to obtain the propylene-butene copolymerized polypropylene material.

[0012] The third aspect of the present invention provides a propylene-butane copolymer polypropylene material obtained by the aforementioned preparation method.

[0013] A fourth aspect of the present invention provides an application of the aforementioned polypropylene composition or the aforementioned propylene-butane copolymer polypropylene material in thermoformed plastic packaging products.

[0014] Through the above technical solution, the following beneficial effects are achieved:

[0015] (1) The propylene-butene copolymerized polypropylene material prepared from the polypropylene composition of specific components in the present invention can have excellent rigidity, toughness, low haze and good heat resistance; wherein the propylene-butene copolymerized polypropylene resin has good compatibility with polybutene and can improve the mechanical properties, optical properties and heat resistance of the propylene-butene copolymerized polypropylene material; and other components, especially the nucleating agent, further improve the rigidity of the propylene-butene copolymerized polypropylene material and reduce the haze;

[0016] (2) The specific reactants in the preparation method enable the final propylene-butane copolymer polypropylene material to have excellent mechanical properties, optical properties and heat resistance. DETAILED DESCRIPTION

[0017] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0018] The first aspect of the present invention protects a propylene-butene copolymer polypropylene composition, wherein the composition comprises: a propylene-butene copolymer polypropylene resin, polybutene, an antioxidant, a halogen absorber and a nucleating agent.

[0019] According to the present invention, the propylene-butene copolymer polypropylene resin is 96-98.8 parts by weight, the polybutene is 0.5-3 parts by weight, the antioxidant is 0.1-0.3 parts by weight, the halogen absorber is 0.01-0.06 parts by weight, and the nucleating agent is 0.02-0.4 parts by weight.

[0020] In the present invention, when the amount of each component meets the above range, the rigidity, optical properties and heat resistance of the propylene-butyl copolymer polypropylene material prepared from the composition can be further improved.

[0021] Furthermore, in the composition, the propylene-butene copolymer polypropylene resin is 97-98 parts by weight, the polybutene is 1-2 parts by weight, the antioxidant is 0.15-0.2 parts by weight, the halogen absorber is 0.02-0.05 parts by weight, and the nucleating agent is 0.04-0.24 parts by weight.

[0022] According to the present invention, in the propylene-butene copolymer polypropylene resin, the content of structural units derived from propylene is 95wt%-99.5wt%, and the content of structural units derived from butene is 0.5wt%-5wt%.

[0023] In the present invention, when the above range is met, the compatibility between the components can be improved, which is reflected in the better haze performance of the final material, indicating that the performance of the prepared propylene-butene copolymer polypropylene material is improved.

[0024] Furthermore, in the propylene-butene copolymer polypropylene resin, the content of structural units derived from propylene is 98.5wt%-99.2wt%, and the content of structural units derived from butene is 0.8wt%-1.5wt%.

[0025] According to the present invention, the weight average molecular weight of the propylene-butane copolymer polypropylene resin is 275000-295000 g / mol, preferably 279000-286000 g / mol.

[0026] According to the present invention, the molecular weight distribution index of the propylene-butane copolymerized polypropylene resin is 4-8.

[0027] In the present invention, when the molecular weight distribution index of the propylene-butane copolymerized polypropylene resin can meet the above range, it has excellent processing performance, and the obtained propylene-butane copolymerized polypropylene material has excellent mechanical properties, optical properties and heat resistance.

[0028] Furthermore, the molecular weight distribution index of the propylene-butane copolymer polypropylene resin is 5-6.

[0029] According to the present invention, at 230°C and a load of 2.16 kg, the melt mass flow rate of the propylene-butane copolymerized polypropylene resin is 1-10 g / 10 min, preferably 2-5 g / 10 min.

[0030] According to the present invention, the polybutene is homopolybutene.

[0031] According to the present invention, at 230° C. and a load of 2.16 kg, the melt mass flow rate of the polybutene is 1-5 g / 10 min, preferably 2-3 g / 10 min.

[0032] According to the present invention, the antioxidant comprises a primary antioxidant and a secondary antioxidant.

[0033] According to the present invention, the weight ratio of the primary antioxidant to the secondary antioxidant is 1:1-3.

[0034] In the present invention, when the weight ratio of the primary antioxidant to the secondary antioxidant satisfies the above range, the compatibility of the composition is improved, the mixing is made more uniform, and the mechanical properties and optical properties of the obtained propylene-butyl copolymer polypropylene material are enhanced.

[0035] Furthermore, the weight ratio of the primary antioxidant to the secondary antioxidant is 1:1.5-2.5.

[0036] According to the present invention, the primary antioxidant is selected from phenolic antioxidants.

[0037] According to the present invention, the secondary antioxidant is selected from phosphite antioxidants.

[0038] In the present invention, specific types of antioxidants can further improve the processing stability of the composition, thereby improving the mechanical properties and heat resistance.

[0039] According to the present invention, the phenolic antioxidant is selected from at least one of tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] pentaerythritol ester, catechol, resorcinol, 3,9-bis[1,1-dimethyl-2-[(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]ethyl]-2,4,8,10-tetraoxaspiro[5.5]undecane and triethylene glycol bis-3-(3-tert-butyl-4-hydroxy-5-methylphenyl)acrylonitrile, and is preferably tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] pentaerythritol ester.

[0040] According to the present invention, the phosphite antioxidant is selected from tris(2,4-di-tert-butylphenyl) phosphite and / or pentaerythritol diisodecyl diphosphite, preferably tris(2,4-di-tert-butylphenyl) phosphite.

[0041] In a particularly preferred embodiment of the present invention, the primary antioxidant is antioxidant 1010.

[0042] In a particularly preferred embodiment of the present invention, the secondary antioxidant is antioxidant 168.

[0043] According to the present invention, the halogen absorber is selected from calcium stearate and / or hydrotalcite, preferably calcium stearate.

[0044] According to the present invention, the nucleating agent is selected from polypropylene nucleating agents.

[0045] In the present invention, the specific nucleating agent can improve the rigidity of the prepared propylene-butyl copolymer polypropylene material and reduce the haze.

[0046] In a particularly preferred embodiment of the present invention, the nucleating agent is selected from at least one of the nucleating agent Milliken HPN-20E, the nucleating agent Milliken NX8000 and the Longpu nucleating agent 9086, preferably selected from the nucleating agent Milliken HPN-20E and / or the nucleating agent Milliken NX8000.

[0047] The second aspect of the present invention protects a method for preparing a propylene-butyl copolymer polypropylene material, wherein the preparation method comprises the following steps:

[0048] (1) adding propylene and 1-butene in the presence of a catalyst to carry out polymerization reaction to obtain a propylene-butene copolymer polypropylene resin;

[0049] (2) The propylene-butene copolymerized polypropylene resin, polybutene, an antioxidant, a halogen absorber and a nucleating agent are mixed and melt-extruded to obtain the propylene-butene copolymerized polypropylene material.

[0050] In the present invention, the specific reactants in the preparation method enable the finally obtained propylene-butyl copolymer polypropylene material to have excellent mechanical properties, optical properties and heat resistance.

[0051] In the present invention, the polymerization reaction may use a reactor commonly used in the art. In a particularly preferred embodiment, the polymerization reaction is carried out in a series of double loop reactors.

[0052] According to the present invention, in step (1), the weight ratio of the propylene to the 1-butene is 1.5-60:1.

[0053] In the present invention, when the amounts of propylene and 1-butene meet the above ranges, the polymerization reaction can be fully carried out, thereby enhancing the mechanical properties, optical properties, and heat resistance of the obtained propylene-butene copolymer polypropylene material.

[0054] Furthermore, the weight ratio of the propylene to the 1-butene is 5-55:1.

[0055] In the present invention, the catalyst can catalyze and accelerate the reaction, can adjust the molecular structure of the polymer, and optimize the mechanical and optical properties. The amount of the catalyst is not limited, as long as the catalytic performance can be achieved.

[0056] In the present invention, the catalyst is a conventional Ziegler-Natta (ZN) catalyst in the art. In a particularly preferred embodiment, the Ziegler-Natta (ZN) catalyst comprises: a main catalyst (DQC602), a co-catalyst (triethylaluminum, TEAL) and an external electron donor (cyclohexyl-methyl-dimethoxysilane, Donor C); which can be commercially purchased from Sinopec Catalyst Co., Ltd.

[0057] According to the present invention, in step (1), the polymerization reaction is carried out in the presence of hydrogen.

[0058] According to the present invention, the polymerization reaction conditions include: polymerization reaction temperature of 64-72° C., polymerization reaction time of 0.5-2 h, polymerization reaction pressure of 3.4-4 MPa, and hydrogen concentration of 1500-3200 ppm during the polymerization reaction.

[0059] In the present invention, the polymerization reaction pressure refers to the pressure of the reaction slurry.

[0060] When the concentration of hydrogen during the polymerization reaction satisfies the above range, the weight average molecular weight of the obtained propylene-butyl copolymer polypropylene resin can be appropriately adjusted.

[0061] Polymerization in a double loop reactor in series 2 Concentration (R201) and H 2 The concentrations (R202) can be the same or different.

[0062] R201 and R202 are different position numbers of the double loop reactor.

[0063] Furthermore, the polymerization reaction conditions include: a polymerization reaction temperature of 65-70° C., a polymerization reaction time of 1.5-1.7 h, a polymerization reaction pressure of 3.5-3.7 MPa, and a hydrogen concentration of 1800-3000 ppm during the polymerization reaction.

[0064] The types and amounts of the substances involved in the reaction in the second aspect of the present invention are the same as those in the first aspect and will not be described in detail herein.

[0065] In the present invention, the melt extrusion is a conventional operation method in the art. In a particularly preferred embodiment, the melt extrusion process is carried out by a twin-screw extruder, the temperature of the front part of the barrel of the twin-screw extruder is 200-230°C, the temperature of the middle part of the barrel is 200-240°C, the temperature of the rear part of the barrel is 210-230°C, the temperature of the unloading section is 180-210°C, and the screw speed is 200-250r / min.

[0066] The third aspect of the present invention provides a propylene-butane copolymer polypropylene material obtained by the aforementioned preparation method.

[0067] According to the present invention, the propylene-butene copolymer polypropylene material has a flexural modulus of >1500MPa, a tensile yield stress of >30MPa, and a notched impact strength of 4-7kJ / m 2 , haze <30% and load heat deformation temperature of 95-105℃.

[0068] Furthermore, the propylene-butane copolymer polypropylene material has a flexural modulus of 1550-1750 MPa, a tensile yield stress of 33-37 MPa, and a notched impact strength of 4.5-6.5 kJ / m 2 , haze is 15-29.5% and load heat deformation temperature is 90-103°C.

[0069] The present invention will be described in detail below through examples.

[0070] The haze test is carried out in accordance with GB / T2410 standard. The sample thickness is 1mm. The specific test method is to measure the scattered light flux that deviates from the incident light direction by more than 2.5° through the sample, recorded as lma; the measured transmitted light flux is recorded as lmb; haze = lma / lmb×100%;

[0071] The tensile yield stress test was carried out in accordance with GB / T1040.2, and the test conditions included: the tensile speed was 50 mm / min;

[0072] The flexural modulus test is carried out in accordance with GB / T9341;

[0073] The test of simply supported beam notched impact strength was carried out according to GB / T1043.1, the specimen size was 80×10×4mm, and the notch depth was 2mm;

[0074] The load heat deformation temperature test is carried out in accordance with GB / T1634.2;

[0075] All test items were parallel samples, and the average value was calculated by testing 5 groups.

[0076] DQC602, triethylaluminum (TEAL), cyclohexyl-methyl-dimethoxysilane (Donor C), propylene, 1-butene, polybutene-1 (at 230°C and 2.16 kg load, the melt mass flow rate of polybutene-1 is 3 g / 10 min), antioxidant 1010, antioxidant 168, calcium stearate, nucleating agent Milliken HPN-20E, nucleating agent Milliken NX8000, and Longpu nucleating agent 9086 are all commercially available.

[0077] Example 1

[0078] (1) In the series-connected double loop reactor, the flow rate of the main catalyst DQC602 is 1.35 kg / h, the flow rate of triethylaluminum is 5 kg / h, and the flow rate of cyclohexyl-methyl-dimethoxysilane is 0.5 kg / h, so that the flow rate ratio of triethylaluminum to cyclohexyl-methyl-dimethoxysilane is 10, the outer loop pressure is 3.7 MPa, the loop temperature is 70°C, and H 2 Concentration (R201) is 1800ml / m 3 , H 2 Concentration (R202) is 2000ml / m 3 , 30t of propylene and 4000kg of 1-butene were introduced, and the mixture stayed for 1.5h to obtain propylene-butene copolymer polypropylene resin;

[0079] In the propylene-butene copolymer polypropylene resin, the content of structural units derived from propylene is 98.8wt%, and the content of structural units derived from butene is 1.2wt%.

[0080] The weight average molecular weight of the propylene-butane copolymerized polypropylene resin is 281000 g / mol; the molecular weight distribution index of the propylene-butane copolymerized polypropylene resin is 5.2; at 230° C. and a load of 2.16 kg, the melt mass flow rate of the propylene-butane copolymerized polypropylene resin is 3.01 g / 10 min.

[0081] (2) Add propylene copolymer polypropylene resin, polybutene, antioxidant, calcium stearate and nucleating agent and mix evenly, and extrude granules through a twin-screw extruder. The temperature of the rear part of the barrel is 230° C., the temperature of the middle part of the barrel is 230° C., the temperature of the front part of the barrel is 200° C., and the temperature of the unloading section is 190° C.

[0082] Examples 2-8 and Comparative Examples 1-3 were implemented in the manner of Example 1. The specific types and amounts of propylene-butene copolymerized polypropylene resin, polybutene, antioxidant 1010, antioxidant 168 calcium stearate and nucleating agent are shown in Table 1.

[0083] Table 1

[0084]

[0085] Note: The units of the amounts of each component added in Table 1 are all parts by weight.

[0086] Examples 9-11

[0087] The method of Example 1 was followed, except that the amounts of propylene used were 29t, 28.5t, and 28t, respectively; the amounts of 1-butene used were 530kg, 1070kg, and 2520kg, respectively;

[0088] In the propylene-butene copolymer polypropylene resin prepared in Example 9, the content of structural units derived from propylene is 98.5wt%, and the content of structural units derived from butene is 1.5wt%; the weight average molecular weight of the propylene-butene copolymer polypropylene resin is 285000g / mol; the molecular weight distribution index of the propylene-butene copolymer polypropylene resin is 5.3; at 230°C and a load of 2.16kg, the melt mass flow rate of the propylene-butene copolymer polypropylene resin is 2.3g / 10min.

[0089] In the propylene-butene copolymer polypropylene resin prepared in Example 10, the content of structural units derived from propylene is 97wt%, and the content of structural units derived from butene is 3wt%; the weight average molecular weight of the propylene-butene copolymer polypropylene resin is 279000g / mol; the molecular weight distribution index of the propylene-butene copolymer polypropylene resin is 5; at 230°C and a load of 2.16kg, the melt mass flow rate of the propylene-butene copolymer polypropylene resin is 3.1g / 10min.

[0090] In the propylene-butene copolymer polypropylene resin prepared in Example 11, the content of structural units derived from propylene is 94.2wt%, and the content of structural units derived from butene is 5.8wt%; the weight average molecular weight of the propylene-butene copolymer polypropylene resin is 280000g / mol; the molecular weight distribution index of the propylene-butene copolymer polypropylene resin is 5.5; at 230°C and a load of 2.16kg, the melt mass flow rate of the propylene-butene copolymer polypropylene resin is 2.9g / 10min.

[0091] The performance tests were performed on the propylene-butane copolymerized polypropylene materials obtained in the examples and comparative examples. The results are shown in Table 2.

[0092] Table 2

[0093]

[0094]

[0095] In propylene-butene copolymer polypropylene materials, the rigidity, toughness, optical properties and heat resistance of the material are usually not achieved at the same time. Generally speaking, the method of reducing the polymer haze requires sacrificing the rigidity and heat resistance of the material, while the method of increasing the rigidity and heat resistance of the polymer will sacrifice the toughness of the material.

[0096] In the present invention, the synergistic effect of propylene-butene copolymerized polypropylene resin and polybutene is utilized to toughen the propylene-butene copolymerized polypropylene material, improve the optical properties and heat resistance, and at the same time, a high-efficiency nucleating agent is added to further improve the rigidity and optical properties of the propylene-butene copolymerized polypropylene resin.

[0097] Comparative Examples 9-11 show that by adjusting the dosage of propylene and 1-butene, a specific dosage can further reduce the haze, proving that the compatibility between the components is improved, thereby improving the comprehensive performance of the propylene-butene copolymer polypropylene material.

[0098] Comparative Example 1 does not add nucleating agent and polybutene. From the data in Table 2, it can be seen that, compared with the examples, Comparative Example 1 has higher haze, lower tensile yield stress and load heat deformation temperature;

[0099] Comparative Example 2 adds nucleating agent HPN20E, which significantly improves the rigidity of the material, as reflected in the higher tensile yield stress, bending modulus, and load deformation temperature. However, since no polybutene is added in Comparative Example 2, the haze of the composite system is high; at the same time, the toughness is also poor, as reflected in the low simply supported beam notched impact strength; the comprehensive effect of mechanical properties and haze of Comparative Example 2 is far inferior to that of the embodiment.

[0100] In Comparative Example 3, no nucleating agent was added, and mechanical properties such as tensile yield stress and flexural modulus decreased, while haze increased and load heat deformation temperature decreased, proving that the present invention should be regarded as an overall solution, and the propylene-butane copolymer polypropylene material prepared by the present invention has better optical properties, better mechanical properties and better heat resistance.

[0101] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A propylene-butyl copolymer polypropylene composition, characterized in that: The composition comprises: propylene-butylene copolymerized polypropylene resin, polybutene, an antioxidant, a halogen absorber and a nucleating agent.

2. The composition according to claim 1, wherein In the composition, the propylene-butene copolymerized polypropylene resin is 96-98.8 parts by weight, the polybutene is 0.5-3 parts by weight, the antioxidant is 0.1-0.3 parts by weight, the halogen absorber is 0.01-0.06 parts by weight, and the nucleating agent is 0.02-0.4 parts by weight; Preferably, in the composition, the propylene-butene copolymerized polypropylene resin is 97-98 parts by weight, the polybutene is 1-2 parts by weight, the antioxidant is 0.15-0.2 parts by weight, the halogen absorber is 0.02-0.05 parts by weight, and the nucleating agent is 0.04-0.24 parts by weight; Preferably, in the propylene-butene copolymer polypropylene resin, the content of structural units derived from propylene is 95wt%-99.5wt%, and the content of structural units derived from butene is 0.5wt%-5wt%; Preferably, in the propylene-butene copolymer polypropylene resin, the content of structural units derived from propylene is 98.5wt%-99.2wt%, and the content of structural units derived from butene is 0.8wt%-1.5wt%; Preferably, the weight average molecular weight of the propylene-butane copolymerized polypropylene resin is 275000-295000 g / mol, preferably 279000-286000 g / mol; Preferably, the molecular weight distribution index of the propylene-butyl copolymer polypropylene resin is 4-8, preferably 5-6; Preferably, at 230° C. and 2.16 kg load, the melt mass flow rate of the propylene-butane copolymerized polypropylene resin is 1-10 g / 10 min; preferably 2-5 g / 10 min; Preferably, the polybutene is homopolybutene; Preferably, at 230° C. and a load of 2.16 kg, the melt mass flow rate of the polybutene is 1-5 g / 10 min; preferably 2-3 g / 10 min.

3. The composition according to claim 1 or 2, wherein The antioxidant comprises a primary antioxidant and a secondary antioxidant; Preferably, the weight ratio of the primary antioxidant to the secondary antioxidant is 1:1-3, preferably 1:1.5-2.5; Preferably, the primary antioxidant is selected from phenolic antioxidants; Preferably, the phenolic antioxidant is at least one selected from pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, catechol, resorcinol, 3,9-bis[1,1-dimethyl-2-[(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]ethyl]-2,4,8,10-tetraoxaspiro[5.5]undecane and triethylene glycol bis-3-(3-tert-butyl-4-hydroxy-5-methylphenyl)acrylonitrile, preferably pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate; Preferably, the secondary antioxidant is selected from phosphite antioxidants; Preferably, the phosphite antioxidant is selected from tris(2,4-di-tert-butylphenyl) phosphite and / or pentaerythritol diisodecyl diphosphite, preferably tris(2,4-di-tert-butylphenyl) phosphite; Preferably, the halogen absorber is selected from calcium stearate and / or hydrotalcite, preferably calcium stearate; Preferably, the nucleating agent is selected from polypropylene nucleating agents; Preferably, the nucleating agent is selected from at least one of the nucleating agent Milliken HPN-20E, the nucleating agent Milliken NX8000 and the Longpu nucleating agent 9086, preferably selected from the nucleating agent Milliken HPN-20E and / or the Milliken nucleating agent NX8000.

4. A method for preparing a propylene-butyl copolymer polypropylene material, characterized in that: The preparation method comprises the following steps: (1) adding propylene and 1-butene in the presence of a catalyst to carry out polymerization reaction to obtain a propylene-butene copolymer polypropylene resin; (2) The propylene-butene copolymerized polypropylene resin, polybutene, an antioxidant, a halogen absorber and a nucleating agent are mixed and melt-extruded to obtain the propylene-butene copolymerized polypropylene material.

5. The preparation method according to claim 4, wherein In step (1), the weight ratio of the propylene to the 1-butene is 1.5-60:1, preferably 5-55:

1.

6. The preparation method according to claim 4 or 5, wherein: In step (1), the polymerization reaction is carried out in the presence of hydrogen; Preferably, the polymerization reaction conditions include: polymerization reaction temperature of 64-72° C., polymerization reaction time of 0.5-2 h, polymerization reaction pressure of 3.4-4 MPa, and hydrogen concentration of 1500-3200 ppm during the polymerization reaction; Preferably, the polymerization reaction conditions include: polymerization reaction temperature of 65-70° C., polymerization reaction time of 1.5-1.7 h, polymerization reaction pressure of 3.5-3.7 MPa, and hydrogen concentration of 1800-3000 ppm during the polymerization reaction.

7. The preparation method according to any one of claims 4 to 6, wherein: In step (2), the propylene-butene copolymerized polypropylene resin is 96-98.8 parts by weight, the polybutene is 0.5-3 parts by weight, the antioxidant is 0.1-0.3 parts by weight, the halogen absorber is 0.01-0.05 parts by weight, and the nucleating agent is 0.02-0.4 parts by weight; Preferably, the propylene-butene copolymer polypropylene resin is 97-98 parts by weight, the polybutene is 1-2 parts by weight, the antioxidant is 0.15-0.2 parts by weight, the halogen absorber is 0.02-0.04 parts by weight, and the nucleating agent is 0.04-0.24 parts by weight.

8. The preparation method according to any one of claims 4 to 7, wherein: In step (2), the weight average molecular weight of the propylene-butane copolymerized polypropylene resin is 275000-295000 g / mol, preferably 279000-286000 g / mol; Preferably, the molecular weight distribution index of the propylene-butyl copolymer polypropylene resin is 4-8, preferably 5-6; Preferably, the polybutene is homopolybutene; Preferably, at 230° C. and a load of 2.16 kg, the melt mass flow rate of the polybutene is 1-5 g / 10 min; preferably 2-3 g / 10 min; Preferably, the antioxidant comprises a primary antioxidant and a secondary antioxidant; Preferably, the weight ratio of the primary antioxidant to the secondary antioxidant is 1:1-3, preferably 1:1.5-2.5; Preferably, the primary antioxidant is selected from phenolic antioxidants; Preferably, the phenolic antioxidant is at least one selected from pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, catechol, resorcinol, 3,9-bis[1,1-dimethyl-2-[(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]ethyl]-2,4,8,10-tetraoxaspiro[5.5]undecane and triethylene glycol bis-3-(3-tert-butyl-4-hydroxy-5-methylphenyl)acrylonitrile, preferably pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate; Preferably, the secondary antioxidant is selected from phosphite antioxidants; Preferably, the phosphite antioxidant is selected from tris(2,4-di-tert-butylphenyl) phosphite and / or pentaerythritol diisodecyl diphosphite, preferably tris(2,4-di-tert-butylphenyl) phosphite; Preferably, the halogen absorber is selected from calcium stearate and / or hydrotalcite, preferably calcium stearate; Preferably, the nucleating agent is selected from polypropylene nucleating agents; Preferably, the nucleating agent is selected from at least one of the nucleating agent Milliken HPN-20E, the nucleating agent Milliken NX8000 and the Longpu nucleating agent 9086, preferably selected from the nucleating agent Milliken HPN-20E and / or the Milliken nucleating agent NX8000.

9. The propylene-butyl copolymer polypropylene material prepared by the preparation method according to any one of claims 4 to 8; Preferably, the propylene-butadiene copolymer polypropylene material has a flexural modulus of >1500MPa, a tensile yield stress of >30MPa, and a notched impact strength of 4-7kJ / m 2 , haze <30% and load heat deformation temperature of 95-105°C; Preferably, the propylene-butene copolymer polypropylene material has a flexural modulus of 1550-1750 MPa, a tensile yield stress of 33-37 MPa, and a notched impact strength of 4.5-6.5 kJ / m 2 , haze is 15-29.5% and load heat deformation temperature is 90-103°C.

10. Use of the polypropylene composition described in any one of claims 1 to 3 or the propylene-butane copolymer polypropylene material described in claim 9 in thermoformed plastic packaging products.

Images