Random propylene butylene copolymerized polypropylene resin, its preparation method and application

Abstract

The application relates to the technical field of polypropylene resins, and discloses a random propylene-butylene copolymerized polypropylene resin as well as a preparation method and application thereof. The random propylene-butylene copolymerized polypropylene resin contains random propylene-butylene copolymerized polypropylene powder and C9 hydrogenated petroleum resin, wherein the random propylene-butylene copolymerized polypropylene resin has a melt index of 2.5-3.5 g / 10 min under a load of 230 DEG C and 2.16 kg, a butene bonding content of 0.1-2 wt%, a molecular weight distribution index of 5.5-7, and a melting point of the C9 hydrogenated petroleum resin of 125-135 DEG C. The random propylene-butylene copolymerized polypropylene resin disclosed by the application can not only maintain excellent stiffness, but also has better processing performance, optical performance and mechanical performance.

Description

Technical Field

[0001] This invention relates to the field of polypropylene resin technology, specifically to a random propylene-butadiene copolymer polypropylene resin, its preparation method, and its application. Background Technology

[0002] Currently, the polypropylene market is mainly dominated by homopolymer polypropylene and ethylene-propylene random copolymer polypropylene. Over 95% of polypropylene plants still produce ordinary homopolymer and ethylene-propylene copolymer products. However, homopolymer polypropylene has relatively large spherulites, resulting in a high probability of light reflection, refraction, and scattering, leading to poor transparency in the finished product and limiting its applications. To address this issue, a common method is to add additives such as nucleating agents to reduce spherulite size, thereby improving the optical properties of homopolymer polypropylene. However, the addition of nucleating agents significantly increases product costs. Another strategy is to add a second monomer during the polymerization reaction for copolymerization, typically ethylene. However, the addition of ethylene increases the content of small molecules in the product, making it unsuitable for high-hygiene applications such as food and medical fields. Furthermore, ethylene bonding can cause the polypropylene film to soften, resulting in reduced mechanical properties. Summary of the Invention

[0003] The purpose of this invention is to overcome the problems of low stiffness, poor optical and mechanical properties of polypropylene films in the prior art, and to provide a random propylene-butadiene polypropylene resin, its preparation method and application. This technical solution limits the proportion and molecular weight distribution of the comonomers in the propylene-butadiene copolymer polypropylene resin, as well as the melting point and amount of C9 hydrogenated resin, so that the bistretched film product can maintain excellent stiffness and also have good optical properties. At the same time, the low molecular weight content is low, thereby avoiding the problem of precipitates on the film surface.

[0004] To achieve the above objectives, the first aspect of the present invention provides a random propylene-butadiene copolymer polypropylene resin, which contains random propylene-butadiene copolymer polypropylene powder and C9 hydrogenated petroleum resin, wherein the random propylene-butadiene copolymer polypropylene resin has a melt index of 2.5-3.5 g / 10 min at 230°C and 2.16 kg load, a bonded butene content of 0.1-2 wt%, a molecular weight distribution index of 5.5-7, and the C9 hydrogenated petroleum resin has a melting point of 125-135°C.

[0005] Preferably, the yellow index of the random propylene-butadiene copolymer polypropylene resin is below 1, and more preferably -3.5 to -0.8.

[0006] Preferably, the atactic propylene-butadiene copolymer polypropylene resin further comprises a primary antioxidant, a secondary antioxidant, and a halogen absorbent, and based on the total weight of the atactic propylene-butadiene copolymer polypropylene resin, the content of the atactic propylene-butadiene copolymer polypropylene powder is 98.94-99.875 wt%, the content of the primary antioxidant is 0.03-0.1 wt%, the content of the secondary antioxidant is 0.03-0.1 wt%, the content of the halogen absorbent is 0.015-0.06 wt%, and the content of the C9 hydrogenated petroleum resin is 0.05-0.8 wt%.

[0007] Preferably, the primary antioxidant is pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate].

[0008] Preferably, the auxiliary antioxidant is tris[2,4-di-tert-butylphenyl]phosphite.

[0009] Preferably, the halogen absorbent is at least one of calcium stearate, zinc stearate, and hydrotalcite.

[0010] A second aspect of the present invention provides a method for preparing random propylene-butadiene copolymer polypropylene resin, the method comprising the following steps:

[0011] (1) In the presence of an olefin polymerization catalyst, a polymerization raw material containing 1-butene, propylene and hydrogen is subjected to a polymerization reaction to obtain random propylene-butene copolymer polypropylene powder.

[0012] (2) The random propylene-butadiene copolymer polypropylene powder, C9 hydrogenated petroleum resin and optional main antioxidant, auxiliary antioxidant and halogen absorbent are mixed and melt-granulated, wherein the melting point of the C9 hydrogenated petroleum resin is 125-135℃.

[0013] Preferably, in step (1), the polymerization reaction is carried out in two reactors connected in series. The reactants obtained after the reaction in the first reactor enter the second reactor to continue the reaction, and the hydrogen concentration in the second reactor is controlled to be 4-40 times that of the hydrogen concentration in the first reactor.

[0014] Preferably, the hydrogen concentration in the first reactor is 50-500 ppm, and the hydrogen concentration in the second reactor is 2000-4000 ppm.

[0015] Preferably, the random propylene-butadiene copolymer polypropylene resin has a melt index of 2.5-3.5 g / 10 min at 230°C and 2.16 kg load, a bonded butene content of 0.1-2 wt%, and a molecular weight distribution index of 5.5-7.

[0016] Preferably, in step (1), the conditions for the polymerization reaction include: a temperature of 65-75°C, a pressure of 3-4 MPa, and a time of 1-2.5 h.

[0017] Preferably, in step (2), the total amount of the random propylene-butadiene copolymer polypropylene powder, the main antioxidant, the auxiliary antioxidant, the halogen absorbent, and the C9 hydrogenated petroleum resin is 100 parts by weight, the amount of the random propylene-butadiene copolymer polypropylene powder is 98.94-99.875 parts by weight, the amount of the main antioxidant is 0.03-0.1 parts by weight, the amount of the auxiliary antioxidant is 0.03-0.1 parts by weight, the amount of the halogen absorbent is 0.015-0.06 parts by weight, and the amount of the C9 hydrogenated petroleum resin is 0.05-0.8 parts by weight.

[0018] Preferably, the primary antioxidant is pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate].

[0019] Preferably, the auxiliary antioxidant is tris[2,4-di-tert-butylphenyl]phosphite.

[0020] Preferably, the halogen absorbent is at least one of calcium stearate, zinc stearate, and hydrotalcite.

[0021] Preferably, in step (2), the conditions for melt granulation include: a temperature of 180-260℃ and an extruder load controlled at 25.5-28t / h.

[0022] A third aspect of the present invention provides a random propylene-butyl copolymer polypropylene resin prepared by the above-described method.

[0023] The fourth aspect of the present invention provides the application of the above-mentioned random propylene-butadiene copolymer polypropylene resin in label films.

[0024] Compared with the prior art, the technical effects of the present invention are as follows:

[0025] (1) The random propylene-butadiene copolymer polypropylene resin of the present invention, through the limitation of the additive formulation, especially the limitation of the C9 hydrogenated petroleum resin with a melting point of 125-135℃, and the bonding butene content and molecular weight distribution of the random propylene-butadiene copolymer polypropylene resin, enables the film products made by using the random propylene-butadiene copolymer polypropylene resin of the present invention after bistretching to maintain excellent stiffness and also have good optical properties.

[0026] (2) The random propylene-butadiene copolymer polypropylene resin of the present invention has excellent processing fluidity, good film-forming properties, few crystal points, and good physical and mechanical properties by adjusting the molecular weight distribution range and limiting the content of bonded butene. It is widely used in many application fields such as packaging, tape, and label film.

[0027] (3) The biaxially oriented polypropylene (BOPP) film prepared by the random propylene-butadiene copolymer polypropylene resin of the present invention through the flat film biaxial stretching process has the advantages of excellent processing performance, wide stretching process window, good film formation, high film stiffness, low precipitation, few crystal points and good mechanical properties. It is widely used in many application fields such as packaging, tape, and label film. Detailed Implementation

[0028] The following provides a detailed description of specific embodiments of the present invention. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0029] The endpoints and any values ​​of the ranges disclosed herein 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 the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0030] The random propylene-butadiene copolymer polypropylene resin of this invention comprises random propylene-butadiene copolymer polypropylene powder and C9 hydrogenated petroleum resin. The random propylene-butadiene copolymer polypropylene resin has a melt index of 2.5-3.5 g / 10 min at 230°C and a load of 2.16 kg, a bonded butene content of 0.1-2 wt%, and a molecular weight distribution index of 5.5-7. The C9 hydrogenated petroleum resin has a melting point of 125-135°C. By limiting the melting point of the C9 hydrogenated petroleum resin (125-135°C) and the bonded butene content and molecular weight distribution of the random propylene-butadiene copolymer polypropylene resin, the film products prepared by bistretching using the random propylene-butadiene copolymer polypropylene resin of this invention can maintain excellent stiffness and also possess good optical properties.

[0031] In the random propylene-butadiene copolymer polypropylene resin of the present invention, in order to improve optical properties, the yellow index of the random propylene-butadiene copolymer polypropylene resin is preferably less than 1, and more preferably -3.5 to -0.8.

[0032] In the atactic propylene-butadiene copolymer polypropylene resin of the present invention, the atactic propylene-butadiene copolymer polypropylene resin may further contain a primary antioxidant, a secondary antioxidant, and a halogen absorbent. Based on the total weight of the atactic propylene-butadiene copolymer polypropylene resin, the content of the atactic propylene-butadiene copolymer polypropylene powder may be 98.94-99.875 wt%, preferably 99-99.8 wt%; the content of the primary antioxidant may be 0.03-0.1 wt%, preferably 0.04-0.1 wt%; the content of the secondary antioxidant may be 0.03-0.1 wt%, preferably 0.04-0.1 wt%; the content of the halogen absorbent may be 0.015-0.06 wt%, preferably 0.02-0.05 wt%; and the content of the C9 hydrogenated petroleum resin may be 0.05-0.8 wt%, preferably 0.1-0.75 wt%.

[0033] In the atactic propylene-butyl copolymer polypropylene resin of the present invention, the primary antioxidant can be at least one of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 1,3,5-tris[[4-(1,1-dimethylethyl)-3-hydroxy-2,6-dimethylphenyl]methyl]-1,3,5-triazine-2,4,6-trione, N,N'-bis-(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)hexamethylenediamine, and 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, preferably pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]. The primary antioxidant is beneficial for improving the antioxidant properties of the atactic propylene-butyl copolymer polypropylene resin and enhancing the mechanical properties of the resulting film material, thereby improving stability.

[0034] In the atactic propylene-butadiene copolymer polypropylene resin of the present invention, the auxiliary antioxidant can be at least one selected from tris[2,4-di-tert-butylphenyl]phosphite, pentaerythritol diphosphite (bis(2,4-di-tert-butylphenyl)), and 3,9-bisoctadecyloxy-2,4,8,10-tetraoxo-3,9-diphosphospiro[5.5]undecane, preferably tris[2,4-di-tert-butylphenyl]phosphite. The auxiliary antioxidant and the primary antioxidant work synergistically to improve the oxidation resistance of the atactic propylene-butadiene copolymer polypropylene resin, preventing oxidative degradation, thereby extending its service life and maintaining the stability of its mechanical and optical properties.

[0035] In the atactic propylene-butadiene copolymer polypropylene resin of the present invention, the halogen absorbent can be at least one of calcium stearate, zinc stearate, and hydrotalcite, preferably calcium stearate. The halogen absorbent has a lower molecular weight content, thereby avoiding the presence of precipitates on the surface of the film product obtained from it.

[0036] In some embodiments, the atactic propylene-butadiene copolymer polypropylene resin of the present invention contains atactic propylene-butadiene copolymer polypropylene powder, C9 hydrogenated petroleum resin, primary antioxidant, secondary antioxidant, and halogen absorbent. The atactic propylene-butadiene copolymer polypropylene resin has a melt index of 2.5-3.5 g / 10 min at 230°C and a load of 2.16 kg, a bonded butene content of 0.1-2 wt%, and a molecular weight distribution index of 5.5-7. The melting point of the C9 hydrogenated petroleum resin is... The temperature is 125-135℃; based on the total weight of the random propylene-butadiene copolymer polypropylene resin, the content of the random propylene-butadiene copolymer polypropylene powder is 98.94-99.875 wt%, the content of the main antioxidant is 0.03-0.1 wt%, the content of the auxiliary antioxidant is 0.03-0.1 wt%, the content of the halogen absorbent is 0.015-0.06 wt%, and the content of the C9 hydrogenated petroleum resin is 0.05-0.8 wt%.

[0037] In other embodiments, the random propylene-butadiene copolymer polypropylene resin of the present invention contains random propylene-butadiene copolymer polypropylene powder, C9 hydrogenated petroleum resin, pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], tris[2,4-di-tert-butylphenyl] phosphite, and a halogen absorbent. The random propylene-butadiene copolymer polypropylene resin has a melt index of 2.5-3.5 g / 10 min at 230°C and a load of 2.16 kg, a bonded butene content of 0.1-2 wt%, and a molecular weight distribution index of 5.5-7. The C9 hydrogenated petroleum resin... The resin has a melting point of 125-135℃; the halogen absorber is at least one of calcium stearate, zinc stearate, and hydrotalcite; based on the total weight of the random propylene-butadiene copolymer polypropylene resin, the content of the random propylene-butadiene copolymer polypropylene powder is 98.94-99.875 wt%, the content of the main antioxidant is 0.03-0.1 wt%, the content of the auxiliary antioxidant is 0.03-0.1 wt%, the content of the halogen absorber is 0.015-0.06 wt%, and the content of the C9 hydrogenated petroleum resin is 0.05-0.8 wt%.

[0038] This invention also provides a method for preparing random propylene-butadiene copolymer polypropylene resin, the method comprising the following steps:

[0039] (1) In the presence of an olefin polymerization catalyst, a polymerization raw material containing 1-butene, propylene and hydrogen is subjected to a polymerization reaction to obtain random propylene-butene copolymer polypropylene powder.

[0040] (2) The random propylene-butadiene copolymer polypropylene powder, C9 hydrogenated petroleum resin and optional main antioxidant, auxiliary antioxidant and halogen absorbent are mixed and melt-granulated, wherein the melting point of the C9 hydrogenated petroleum resin is 125-135℃.

[0041] According to the method described in this invention, a polymerization reaction is carried out using 1-butene, propylene, and hydrogen as polymer raw materials, and the melting point of the C9 hydrogenated petroleum resin is defined. The resulting random propylene-butadiene copolymer polypropylene resin, after bistretching, produces a film product that maintains excellent stiffness while also possessing good optical and mechanical properties.

[0042] In the method described in this invention, in step (1), the polymerization reaction is carried out in two reactors connected in series. The reactants obtained after the reaction in the first reactor enter the second reactor to continue the reaction, and the hydrogen concentration in the second reactor is controlled to be 4-40 times that of the hydrogen concentration in the first reactor. By using asymmetric hydrogenation to limit the molecular weight distribution range, the resulting film material has excellent processing fluidity and good physical and mechanical properties.

[0043] In the method described in this invention, the specific process of the polymerization reaction may include: mixing 1-butene and propylene and feeding them into the first reactor, introducing hydrogen gas and carrying out a polymerization reaction in the presence of an olefin polymerization catalyst, and feeding the resulting mixture into the second reactor, introducing hydrogen gas and carrying out a polymerization reaction in the presence of an olefin polymerization catalyst. The reactor may be a loop reactor.

[0044] In the method described in this invention, in order to improve the processing performance and mechanical properties of random propylene-butadiene copolymer polypropylene resin, the hydrogen concentration in the first reactor is preferably 50-500 ppm, more preferably 200-300 ppm; the hydrogen concentration in the second reactor is preferably 2000-4000 ppm, more preferably 2500-4000 ppm.

[0045] In the method described in this invention, the melt index of the atactic propylene-butadiene copolymer polypropylene resin at 230°C and 2.16 kg load can be 2.5-3.5 g / 10 min, preferably 2.8-3.2 g / 10 min; the content of bonded butene can be 0.1-2 wt%, preferably 0.3-1 wt%; and the molecular weight distribution index can be 5.5-7, preferably 6-7. By limiting the bonded butene content and molecular weight distribution range of the atactic propylene-butadiene copolymer polypropylene resin, it is beneficial to improve the processing performance and mechanical properties of the atactic propylene-butadiene copolymer polypropylene resin.

[0046] In the method described in this invention, in step (1), the conditions for the polymerization reaction include: a temperature of 65-75°C, preferably 68-72°C; a pressure of 3-4 MPa, preferably 3.3-3.7 MPa; and a time of 1-2.5 h, preferably 1.5-2.0 h. If the polymerization reaction is carried out in two reactors connected in series, the time of the polymerization reaction is the sum of the polymerization reaction times in the two reactors. The time of the polymerization reaction in the first reactor can be 0.5-1.0 h. The time of the polymerization reaction in the second reactor can be 0.5-1.5 h. In this document, the pressure is gauge pressure.

[0047] In the method described in this invention, in step (1), the olefin polymerization catalyst comprises a main catalyst, a co-catalyst, and an optional external electron donor. The main catalyst may be a combination of DQC602 and oil. The DQC602 is a titanium-based catalyst supported on MgCl2. The co-catalyst may be at least one of triethylaluminum, triisobutylaluminum, and trimethylaluminum, preferably triethylaluminum. The external electron donor may be at least one of cyclohexylmethyldimethoxysilane, n-propyltrimethoxysilane, and n-propyltriethoxysilane, preferably cyclohexylmethyldimethoxysilane. The main catalyst, the co-catalyst, and the external electron donor can be commercially available. The mass ratio of the external electron donor to the co-catalyst may be (0-0.5):1, preferably (0.1-0.3):1. The mass ratio of the co-catalyst to the propylene may be (0.05-0.15) kg:1 t, preferably (0.1-0.15) kg:1 t. The mass ratio of the main catalyst to the propylene can be 1g:(50-100)kg, preferably 1g:(60-80)kg.

[0048] In the method described in this invention, in step (2), the total amount of the random propylene-butadiene copolymer polypropylene powder, the main antioxidant, the auxiliary antioxidant, the halogen absorbent, and the C9 hydrogenated petroleum resin is 100 parts by weight. The amount of the random propylene-butadiene copolymer polypropylene powder can be 98.94-99.875 parts by weight, preferably 99-99.8 parts by weight; the amount of the main antioxidant can be 0.03-0.1 parts by weight, preferably 0.04-0.1 parts by weight; the amount of the auxiliary antioxidant can be 0.03-0.1 parts by weight, preferably 0.04-0.1 parts by weight; the amount of the halogen absorbent can be 0.015-0.06 parts by weight, preferably 0.02-0.05 parts by weight; and the amount of the C9 hydrogenated petroleum resin can be 0.05-0.8 parts by weight, preferably 0.1-0.75 parts by weight. By limiting the raw material formulation for preparing atactic propylene-butadiene copolymer polypropylene resin, the atactic propylene-butadiene copolymer polypropylene resin can possess both excellent processing performance and physical and mechanical properties.

[0049] In the method described in this invention, the primary antioxidant can be at least one of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 1,3,5-tris[[4-(1,1-dimethylethyl)-3-hydroxy-2,6-dimethylphenyl]methyl]-1,3,5-triazine-2,4,6-trione, N,N'-bis-(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)hexamethylenediamine, and 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, preferably pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]. The primary antioxidant is beneficial for improving the antioxidant properties of the atactic propylene-butyl copolymer polypropylene resin and enhancing the mechanical properties of the resulting film material, thereby improving stability.

[0050] In the method described in this invention, the auxiliary antioxidant can be at least one selected from tris[2,4-di-tert-butylphenyl]phosphite, pentaerythritol diphosphite (bis(2,4-di-tert-butylphenyl)), and 3,9-bisoctadecyloxy-2,4,8,10-tetraoxo-3,9-diphosphospiro[5.5]undecane, preferably tris[2,4-di-tert-butylphenyl]phosphite. The auxiliary antioxidant and the primary antioxidant work synergistically to improve the antioxidant properties of the atactic propylene-butadiene copolymer polypropylene resin, preventing oxidative degradation, thereby extending its service life and maintaining the stability of its mechanical and optical properties.

[0051] In the method described in this invention, the halogen absorbent can be at least one of calcium stearate, zinc stearate, and hydrotalcite, preferably calcium stearate. The hydrotalcite can be magnesium aluminum hydroxide dihydroxyl. The halogen absorbent has a lower molecular weight content, thereby avoiding the presence of precipitates on the film surface of the film material made of atactic propylene copolymer polypropylene resin.

[0052] In the method described in this invention, in step (2), the conditions for melt granulation include: a temperature of 180-260℃, preferably 200-250℃; and an extruder load controlled at 25.5-28 t / h, preferably 26-27.5 t / h. The melt granulation can be carried out using an extruder. The mesh size of the extruder's filter screen can be 50-250 mesh, preferably 150-250 mesh.

[0053] In some embodiments, the method for preparing the random propylene-butadiene copolymer polypropylene resin of the present invention includes the following steps:

[0054] (1) In the presence of an olefin polymerization catalyst, a polymerization raw material containing 1-butene, propylene and hydrogen is subjected to a polymerization reaction at a temperature of 65-75°C and a pressure of 3-4 MPa. The polymerization reaction is carried out in two reactors connected in series. The reactant obtained after the reaction in the first reactor enters the second reactor to continue the reaction. The hydrogen concentration in the second reactor is controlled to be 4-40 times that in the first reactor. The hydrogen concentration in the first reactor is 50-500 ppm, and the hydrogen concentration in the second reactor is 2000-4000 ppm. The polymerization reaction in the first reactor is 0.5-1 h, and the polymerization reaction in the second reactor is 1.0-1.5 h, to obtain random propylene-butene copolymer polypropylene powder.

[0055] (2) The random propylene-butadiene copolymer polypropylene powder, C9 hydrogenated petroleum resin, and optional primary antioxidant, secondary antioxidant, and halogen absorbent are mixed and melt-granulated at a temperature of 180-260℃, with the extruder load controlled at 25.5-28 t / h. The melting point of the C9 hydrogenated petroleum resin is 125-135℃, the amount of the random propylene-butadiene copolymer polypropylene powder is 98.94-99.875 parts by weight, the amount of the primary antioxidant is 0.03-0.1 parts by weight, the amount of the secondary antioxidant is 0.03-0.1 parts by weight, the amount of the halogen absorbent is 0.015-0.06 parts by weight, and the amount of the C9 hydrogenated petroleum resin is 0.05-0.8 parts by weight.

[0056] In other embodiments, the method for preparing the random propylene-butadiene copolymer polypropylene resin of the present invention includes the following steps:

[0057] (1) In the presence of an olefin polymerization catalyst, a polymerization raw material containing 1-butene, propylene and hydrogen is subjected to a polymerization reaction at a temperature of 68-72℃ and a pressure of 3.3-3.7MPa. The polymerization reaction is carried out in two reactors connected in series. The reactant obtained after the reaction in the first reactor enters the second reactor to continue the reaction. The hydrogen concentration in the second reactor is controlled to be 10-20 times that in the first reactor. The hydrogen concentration in the first reactor is 200-300ppm, and the hydrogen concentration in the second reactor is 2500-4000ppm. The polymerization reaction in the first reactor lasts for 0.5-1.0h, and the polymerization reaction in the second reactor lasts for 1.0-1.5h, to obtain random propylene-butene copolymer polypropylene powder.

[0058] (2) The random propylene-butadiene copolymer polypropylene powder, C9 hydrogenated petroleum resin, and optionally pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], tris[2,4-di-tert-butylphenyl]phosphite, and halogen absorbent are mixed and melt-granulated at a temperature of 200-250°C. The extruder load is controlled at 25.5-28 t / h. The melting point of the C9 hydrogenated petroleum resin is 125-135°C, and the halogen absorbent is calcium stearate or zinc stearate. The mixture comprises at least one of hydrotalcite and attribution, wherein the amount of the random propylene-butadiene copolymer polypropylene powder is 99-99.8 parts by weight, the amount of the pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] is 0.04-0.1 parts by weight, the amount of the tris[2,4-di-tert-butylphenyl] phosphite is 0.04-0.1 parts by weight, the amount of the halogen absorbent is 0.02-0.05 parts by weight, and the amount of the C9 hydrogenated petroleum resin is 0.1-0.75 parts by weight.

[0059] The present invention also provides a random propylene-butadiene copolymer polypropylene resin prepared by the above method. Film materials prepared from the random propylene-butadiene copolymer polypropylene resin of the present invention maintain excellent stiffness while also possessing good processability, optical properties, and mechanical properties.

[0060] This invention also provides the application of the above-mentioned atactic propylene-butadiene copolymer polypropylene resin in label films. The film material prepared from the atactic propylene-butadiene copolymer polypropylene resin of this invention has high stiffness and excellent optical properties. The atactic propylene-butadiene copolymer polypropylene resin exhibits excellent processing performance, a wide stretching process window, good film formation, high film stiffness, low precipitation, few crystal points, and excellent mechanical properties during bistretching, which can meet the requirements of downstream applications in the label film field.

[0061] The following examples further illustrate the random propylene-butadiene copolymer polypropylene resin, its preparation method, and its applications according to the present invention. These examples are implemented based on the technical solution of the present invention, providing detailed implementation methods and specific operating procedures; however, the scope of protection of the present invention is not limited to the following examples.

[0062] Unless otherwise specified, the experimental methods used in the following examples are conventional methods in the art. Unless otherwise specified, the experimental materials used in the following examples are commercially available. The main catalyst was purchased from Beijing Aoda Branch of Sinopec Catalyst Co., Ltd.; the triethylaluminum was purchased from Nourion Chemicals Co., Ltd.; and the cyclohexylmethyldimethoxysilane was purchased from Shandong Lujing Chemical Technology Co., Ltd.

[0063] Example 1

[0064] (1) 1-Butene and propylene are mixed and fed into the first loop reactor. Hydrogen gas (concentration of hydrogen gas is 220 ppm) is introduced and polymerization is carried out at 70°C and 3.5 MPa for 0.5 h in the presence of an olefin polymerization catalyst (the olefin polymerization catalyst contains a main catalyst, cyclohexylmethyldimethoxysilane and triethylaluminum, the main catalyst is DQC602 and oil, the mass ratio of the main catalyst to the propylene is 1 g: 75 kg, the mass ratio of cyclohexylmethyldimethoxysilane to the triethylaluminum is 0.2:1, and the mass ratio of the triethylaluminum to the propylene is 0.13 kg: 1 t). The resulting mixture is fed into the second loop reactor. Hydrogen gas (concentration of hydrogen gas is 3800 ppm) is introduced and polymerization is carried out at 70°C and 3.5 MPa for 1.0 h in the presence of the olefin polymerization catalyst to obtain random propylene-butene copolymer polypropylene powder.

[0065] (2) 99.7 parts by weight of the random propylene-butadiene copolymer polypropylene powder obtained in step (1), 0.1 parts by weight of C9 hydrogenated petroleum resin (melting point 130℃), 0.075 parts by weight of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 0.075 parts by weight of tris[2,4-di-tert-butylphenyl] phosphite and 0.05 parts by weight of calcium stearate are mixed and melt-granulated through an extruder (the mesh size of the filter screen of the extruder is 150-250 mesh) at a temperature of 230℃, with the extruder load controlled at 27.5 t / h.

[0066] Example 2

[0067] (1) 1-Butene and propylene are mixed and fed into the first loop reactor. Hydrogen gas (concentration of hydrogen gas is 280 ppm) is introduced and polymerization is carried out at 70°C and 3.5 MPa for 0.5 h in the presence of an olefin polymerization catalyst (the olefin polymerization catalyst contains a main catalyst, cyclohexylmethyldimethoxysilane and triethylaluminum, the main catalyst is DQC602 and oil, the mass ratio of the main catalyst to the propylene is 1 g: 50 kg, the mass ratio of cyclohexylmethyldimethoxysilane to the triethylaluminum is 0.2:1, and the mass ratio of the triethylaluminum to the propylene is 0.13 kg: 1 t). The resulting mixture is fed into the second loop reactor. Hydrogen gas (concentration of hydrogen gas is 3200 ppm) is introduced and polymerization is carried out at 70°C and 3.5 MPa for 1.0 h in the presence of the olefin polymerization catalyst to obtain atactic propylene-butene copolymer polypropylene powder.

[0068] (2) 99.72 parts by weight of the random propylene-butadiene copolymer polypropylene powder obtained in step (1), 0.1 parts by weight of C9 hydrogenated petroleum resin (melting point 130℃), 0.075 parts by weight of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 0.075 parts by weight of tris[2,4-di-tert-butylphenyl] phosphite and 0.03 parts by weight of calcium stearate are mixed and melt-granulated through an extruder (the mesh size of the filter screen of the extruder is 150-250 mesh) at a temperature of 230℃. The extruder load is controlled at 27.5 t / h.

[0069] Example 3

[0070] (1) 1-Butene and propylene are mixed and fed into the first loop reactor. Hydrogen gas (concentration of hydrogen gas is 260 ppm) is introduced and polymerization is carried out at 70°C and 3.5 MPa for 0.5 h in the presence of an olefin polymerization catalyst (the olefin polymerization catalyst contains a main catalyst, cyclohexylmethyldimethoxysilane and triethylaluminum, the main catalyst is DQC602 and oil, the mass ratio of the main catalyst to the propylene is 1 g: 100 kg, the mass ratio of cyclohexylmethyldimethoxysilane to the triethylaluminum is 0.2:1, and the mass ratio of the triethylaluminum to the propylene is 0.13 kg: 1 t). The resulting mixture is fed into the second loop reactor. Hydrogen gas (concentration of hydrogen gas is 2800 ppm) is introduced and polymerization is carried out at 70°C and 3.5 MPa for 1.0 h in the presence of the olefin polymerization catalyst to obtain random propylene-butene copolymer polypropylene powder.

[0071] (2) 99.63 parts by weight of the random propylene-butadiene copolymer polypropylene powder obtained in step (1), 0.2 parts by weight of C9 hydrogenated petroleum resin (melting point 130℃), 0.05 parts by weight of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 0.1 parts by weight of tris[2,4-di-tert-butylphenyl] phosphite and 0.02 parts by weight of calcium stearate are mixed and melt-granulated through an extruder (the mesh size of the filter screen of the extruder is 150-250 mesh) at a temperature of 230℃, with the extruder load controlled at 27.5 t / h.

[0072] Example 4

[0073] (1) 1-Butene and propylene are mixed and fed into the first loop reactor. Hydrogen gas (concentration of hydrogen gas is 230 ppm) is introduced and polymerization is carried out at 70°C and 3.5 MPa for 0.5 h in the presence of an olefin polymerization catalyst (the olefin polymerization catalyst contains a main catalyst, cyclohexylmethyldimethoxysilane and triethylaluminum, the main catalyst is DQC602 and oil, the mass ratio of the main catalyst to the propylene is 1 g: 75 kg, the mass ratio of cyclohexylmethyldimethoxysilane to the triethylaluminum is 0.2:1, and the mass ratio of the triethylaluminum to the propylene is 0.13 kg: 1 t). The resulting mixture is fed into the second loop reactor. Hydrogen gas (concentration of hydrogen gas is 3800 ppm) is introduced and polymerization is carried out at 70°C and 3.5 MPa for 1.0 h in the presence of the olefin polymerization catalyst to obtain random propylene-butene copolymer polypropylene powder.

[0074] (2) 99.53 parts by weight of the random propylene-butadiene copolymer polypropylene powder obtained in step (1), 0.3 parts by weight of C9 hydrogenated petroleum resin (melting point 130℃), 0.05 parts by weight of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 0.1 parts by weight of tris[2,4-di-tert-butylphenyl] phosphite and 0.02 parts by weight of calcium stearate are mixed and melt-granulated through an extruder (the mesh size of the filter screen of the extruder is 150-250 mesh) at a temperature of 230℃, with the extruder load controlled at 27.5 t / h.

[0075] Example 5

[0076] (1) 1-Butene and propylene are mixed and fed into the first loop reactor. Hydrogen gas (concentration of hydrogen gas is 230 ppm) is introduced and polymerization is carried out at 70°C and 3.5 MPa for 0.5 h in the presence of an olefin polymerization catalyst (the olefin polymerization catalyst contains a main catalyst, cyclohexylmethyldimethoxysilane and triethylaluminum, the main catalyst is DQC602 and oil, the mass ratio of the main catalyst to the propylene is 1 g: 75 kg, the mass ratio of cyclohexylmethyldimethoxysilane to the triethylaluminum is 0.2:1, and the mass ratio of the triethylaluminum to the propylene is 0.13 kg: 1 t). The resulting mixture is fed into the second loop reactor. Hydrogen gas (concentration of hydrogen gas is 3200 ppm) is introduced and polymerization is carried out at 70°C and 3.5 MPa for 1.0 h in the presence of the olefin polymerization catalyst to obtain random propylene-butene copolymer polypropylene powder.

[0077] (2) 99.32 parts by weight of the random propylene-butadiene copolymer polypropylene powder obtained in step (1), 0.5 parts by weight of C9 hydrogenated petroleum resin (melting point 130℃), 0.075 parts by weight of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 0.075 parts by weight of tris[2,4-di-tert-butylphenyl] phosphite and 0.03 parts by weight of calcium stearate are mixed and melt-granulated through an extruder (the mesh size of the filter screen of the extruder is 150-250 mesh) at a temperature of 230℃, with the extruder load controlled at 25.5 t / h.

[0078] Example 6

[0079] (1) 1-Butene and propylene are mixed and fed into the first loop reactor. Hydrogen gas (concentration of hydrogen gas is 500 ppm) is introduced and polymerization is carried out at 65°C and 3 MPa for 0.5 h in the presence of an olefin polymerization catalyst (the olefin polymerization catalyst contains a main catalyst and triethylaluminum, the main catalyst is DQC602 and oil, the mass ratio of the main catalyst to the propylene is 1 g: 75 kg, and the mass ratio of the triethylaluminum to the propylene is 0.15 kg: 1 t). The resulting mixture is fed into the second loop reactor. Hydrogen gas (concentration of hydrogen gas is 4000 ppm) is introduced and polymerization is carried out at 65°C and 3 MPa for 0.5 h in the presence of the olefin polymerization catalyst to obtain random propylene-butene copolymer polypropylene powder.

[0080] (2) 98.94 parts by weight of the random propylene-butadiene copolymer polypropylene powder obtained in step (1), 0.8 parts by weight of C9 hydrogenated petroleum resin (melting point 125℃), 0.1 parts by weight of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 0.1 parts by weight of tris[2,4-di-tert-butylphenyl]phosphite and 0.06 parts by weight of zinc stearate are mixed and melt-granulated through an extruder (the mesh size of the filter screen of the extruder is 150-250 mesh) at a temperature of 180℃, with the extruder load controlled at 28t / h.

[0081] Example 7

[0082] (1) 1-Butene and propylene are mixed and fed into the first loop reactor. Hydrogen gas (concentration of hydrogen gas is 50 ppm) is introduced and polymerization is carried out at 75°C and 4 MPa for 1 h in the presence of an olefin polymerization catalyst (the olefin polymerization catalyst contains a main catalyst, cyclohexylmethyldimethoxysilane and triethylaluminum, the main catalyst is DQC602 and oil, the mass ratio of the main catalyst to the propylene is 1 g: 75 kg, the mass ratio of cyclohexylmethyldimethoxysilane to the triethylaluminum is 0.5:1, and the mass ratio of the triethylaluminum to the propylene is 0.05 kg: 1 t). The resulting mixture is fed into the second loop reactor. Hydrogen gas (concentration of hydrogen gas is 2000 ppm) is introduced and polymerization is carried out at 75°C and 4 MPa for 1.5 h in the presence of the olefin polymerization catalyst to obtain random propylene-butene copolymer polypropylene powder.

[0083] (2) 99.875 parts by weight of the random propylene-butadiene copolymer polypropylene powder obtained in step (1), 0.05 parts by weight of C9 hydrogenated petroleum resin (melting point 135℃), 0.03 parts by weight of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 0.03 parts by weight of tris[2,4-di-tert-butylphenyl] phosphite and 0.015 parts by weight of hydrotalcite are mixed and melt-granulated through an extruder (the mesh size of the filter screen of the extruder is 150-250 mesh) at a temperature of 260℃, with the extruder load controlled at 27.5 t / h.

[0084] Comparative Example 1

[0085] The method of Example 1 was implemented, except that the C9 hydrogenated petroleum resin with a melting point of 130°C was replaced with a C9 hydrogenated petroleum resin with a melting point of 100°C.

[0086] Comparative Example 2

[0087] The method of Example 1 was followed, except that the content of bonded butene in the prepared random propylene-butene copolymer polypropylene resin was adjusted to 4 wt%.

[0088] Comparative Example 3

[0089] The method was implemented according to Example 1, except that the hydrogen concentration in the first loop reactor was adjusted to 1000 ppm and the hydrogen concentration in the second loop reactor was adjusted to 3000 ppm.

[0090] Comparative Example 4

[0091] The method of Example 1 was implemented, except that step (2) was not performed. The random propylene-butadiene copolymer polypropylene powder obtained in step (1) was passed through an extruder (the mesh size of the filter screen of the extruder is 150-250 mesh) at a temperature of 230°C and the extruder load was controlled at 27.5t / h.

[0092] Comparative Example 5

[0093] The method of Example 2 was implemented, except that step (2) was omitted, and the random propylene-butadiene copolymer polypropylene powder obtained in step (1) was melt-granulated at a temperature of 230°C through an extruder (the mesh size of the filter screen of the extruder is 150-250 mesh) at a rate of 27.5 t / h.

[0094] Test case

[0095] (1) The melt flow index (referring to the national standard GB / T 3682.1-2018 "Standard Method for Determination of Melt Mass Flow Rate (MFR) and Melt Volume Flow Rate (MVR) of Thermoplastic Plastics", using 230℃ / 2.16kg), molecular weight distribution index (referring to the national standard GB / T 27810-2011), and yellow index (referring to the chemical industry standard HG / T 3862-2006 "Test Method for Yellow Index of Plastics") of the random propylene-butene copolymer polypropylene resins prepared in Examples 1-7 and Comparative Examples 1-5 were measured by Fourier transform infrared spectroscopy and recorded in Table 1. -1 The absorption peak area at 770 cm⁻¹ is a quantitative characteristic value (due to the wavenumber 770 cm⁻¹). -1 The absorption peak area at this point is relatively small, requiring a thicker sample; therefore, a wavenumber of 4323 cm⁻¹ was chosen. -1 The absorption peak height at a certain point was normalized as a sample thickness factor. A strong linear correlation was obtained between the quantitative data and the characteristic data from infrared detection using nuclear magnetic resonance (NMR). The linear correlation equation is as follows:

[0096] Y(mol%)=0.06884+1.23098x(X=A770 / H 4323校正 H 4323校正 =H 4323未校正 -H 4800未

[0097] 校正 Mass percentage conversion formula: Z(m%) = 56Y / (4200 + 14Y)

[0098] (2) The random propylene-butadiene copolymer polypropylene resins prepared in Examples 1-7 and Comparative Examples 1-5 were subjected to tensile yield stress test (referring to national standard GB / T 1040.2-2022 "Determination of tensile properties of plastics"), film optical property test (referring to national standard GB / T 2410-2008 "Determination of light transmittance and haze of transparent plastics"), thermal property test (referring to national standard GB / T 19466.3-2004 "Differential scanning calorimetry (DSC) of plastics - Part 3: Determination of melting and crystallization temperature and enthalpy"), and flexural modulus test (referring to national standard GB / T 9341-2008 "Determination of flexural properties of plastics"), and the results are recorded in Table 2.

[0099] Table 1

[0100]

[0101] Table 2

[0102]

[0103]

[0104] As shown in Table 2, the examples using the random propylene-butadiene copolymer polypropylene resin material described in this invention exhibit high melting points and crystallization temperatures, indicating excellent processing performance and good film-forming properties; high flexural strength, longitudinal tensile yield stress, and transverse tensile yield stress, indicating high stiffness and excellent mechanical properties; simultaneously, low haze and high clarity, indicating excellent optical properties; and fewer fisheyes, indicating fewer crystal points and excellent appearance. The random propylene-butadiene copolymer polypropylene resin described in this invention opens up a new field for propylene-butadiene copolymer film materials in the label film direction.

[0105] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A random propylene-butadiene copolymer polypropylene resin, characterized in that, The random propylene-butadiene copolymer polypropylene resin contains random propylene-butadiene copolymer polypropylene powder and C9 hydrogenated petroleum resin. The random propylene-butadiene copolymer polypropylene resin has a melt index of 2.5-3.5 g / 10 min at 230℃ and 2.16 kg load, a bonded butene content of 0.1-2 wt%, and a molecular weight distribution index of 5.5-7. The C9 hydrogenated petroleum resin has a melting point of 125-135℃.

2. The random propylene-butadiene copolymer polypropylene resin according to claim 1, characterized in that, The yellow index of the random propylene-butadiene copolymer polypropylene resin is below 1, preferably -3.5 to -0.

8.

3. The random propylene-butadiene copolymer polypropylene resin according to claim 1 or 2, characterized in that, The atactic propylene-butadiene copolymer polypropylene resin further contains a primary antioxidant, a secondary antioxidant, and a halogen absorbent. Based on the total weight of the atactic propylene-butadiene copolymer polypropylene resin, the content of the atactic propylene-butadiene copolymer polypropylene powder is 98.94-99.875 wt%, the content of the primary antioxidant is 0.03-0.1 wt%, the content of the secondary antioxidant is 0.03-0.1 wt%, the content of the halogen absorbent is 0.015-0.06 wt%, and the content of the C9 hydrogenated petroleum resin is 0.05-0.8 wt%.

4. The random propylene-butadiene copolymer polypropylene resin according to any one of claims 1-3, characterized in that, The primary antioxidant is pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]; and / or The auxiliary antioxidant is tris[2,4-di-tert-butylphenyl]phosphite; and / or The halogen absorbent is at least one of calcium stearate, zinc stearate, and hydrotalcite.

5. A method for preparing a random propylene-butadiene copolymer polypropylene resin, characterized in that, The method includes the following steps: (1) In the presence of an olefin polymerization catalyst, a polymerization raw material containing 1-butene, propylene and hydrogen is subjected to a polymerization reaction to obtain random propylene-butene copolymer polypropylene powder. (2) The random propylene-butadiene copolymer polypropylene powder, C9 hydrogenated petroleum resin and optional main antioxidant, auxiliary antioxidant and halogen absorbent are mixed and melt-granulated, wherein the melting point of the C9 hydrogenated petroleum resin is 125-135℃.

6. The method according to claim 5, characterized in that, In step (1), the polymerization reaction is carried out in two reactors connected in series. The reactants obtained after the reaction in the first reactor enter the second reactor to continue the reaction, and the hydrogen concentration in the second reactor is controlled to be 4-40 times that of the hydrogen concentration in the first reactor. Preferably, the hydrogen concentration in the first reactor is 50-500 ppm, and the hydrogen concentration in the second reactor is 2000-4000 ppm.

7. The method according to claim 6, characterized in that, The random propylene-butadiene copolymer polypropylene resin has a melt index of 2.5-3.5 g / 10 min at 230℃ and 2.16 kg load, a bonded butene content of 0.1-2 wt%, and a molecular weight distribution index of 5.5-7.

8. The method according to any one of claims 5-7, characterized in that, In step (1), the conditions for the polymerization reaction include: a temperature of 65-75°C, a pressure of 3-4 MPa, and a time of 1-2.5 h.

9. The method according to any one of claims 5-8, characterized in that, In step (2), the total amount of the random propylene-butadiene copolymer polypropylene powder, the main antioxidant, the auxiliary antioxidant, the halogen absorbent, and the C9 hydrogenated petroleum resin is 100 parts by weight. The amount of the random propylene-butadiene copolymer polypropylene powder is 98.94-99.875 parts by weight, the amount of the main antioxidant is 0.03-0.1 parts by weight, the amount of the auxiliary antioxidant is 0.03-0.1 parts by weight, the amount of the halogen absorbent is 0.015-0.06 parts by weight, and the amount of the C9 hydrogenated petroleum resin is 0.05-0.8 parts by weight. Preferably, the primary antioxidant is pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]; Preferably, the auxiliary antioxidant is tris[2,4-di-tert-butylphenyl]phosphite; Preferably, the halogen absorbent is at least one of calcium stearate, zinc stearate, and hydrotalcite.

10. The method according to claim 5 or 9, characterized in that, In step (2), the conditions for melt granulation include: a temperature of 180-260℃ and an extruder load controlled at 25.5-28t / h.

11. Atactic propylene-butadiene polypropylene resin prepared by the method according to any one of claims 5-10.

12. The use of the atactic polypropylene resin according to any one of claims 1-4 and 11 in label films.

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