Chlorinated metallocene polypropylene based on metallocene catalysis and preparation method thereof

Abstract

The invention belongs to the technical field of chlorinated high polymer modification, and relates to metallocene polypropylene chloride based on metallocene catalysis and a preparation method thereof. The preparation method of the chlorinated metallocene polypropylene comprises synthesis of metallocene catalyzed polypropylene, pretreatment of metallocene polypropylene and chlorination modification treatment. According to the invention, metallocene polypropylene is combined with a chlorination modification technology, metallocene polypropylene is obtained after metallocene catalysis, then chlorination modification is carried out to obtain a chlorinated high polymer modified by polar functional groups, and the chlorinated metallocene polypropylene not only inherits the advantages of metallocene polypropylene, but also has certain polarity, so that the metallocene polypropylene has a good application prospect. And the resin has wider resin compatibility, and can be applied to printing ink, coating and gelling agent systems.

Description

Technical Field

[0001] The present invention belongs to the technical field of modification of chlorinated polymers, and relates to a metallocene-catalyzed chlorinated metallocene polypropylene and a preparation method thereof. Background Art

[0002] Polypropylene (PP) is a crystalline polymer with a regular structure. It has a low price, strong corrosion resistance, and excellent physical properties, and is widely used in various fields such as construction, energy, chemical industry, and transportation. With the continuous growth of the market demand for high-performance and multifunctional polypropylene materials, traditional polypropylene materials have been difficult to meet the needs of high-end application fields. The application of metallocene catalysts in polypropylene production has become a research hotspot in the industry. Compared with traditional Z-N catalysts, metallocene catalysts have high activity, a stable reaction process, and excellent hydrogen regulation performance. The metallocene polypropylene prepared has characteristics such as a narrow molecular weight distribution, small microcrystalline structure, superior impact strength and toughness, and good resin compatibility. The polypropylene (mPP) prepared using metallocene catalysts has characteristics such as high strength, high heat resistance, and good moldability compared with traditional polypropylene. However, metallocene catalysts have high activity and are prone to a relatively fast local polymerization rate during the polymerization reaction, which affects the polymerization effect and even poses a risk of explosion polymerization. Chlorinated modified polypropylene has been industrially produced since the 1960s due to its excellent flame retardancy, plasticization, and other characteristics. Depending on the content, it can be used in fields such as coatings, adhesives, and additives for flammable materials. Currently, there are few studies on the chlorination modification of metallocene polypropylene. By integrating the advantages of metallocene polypropylene and chlorinated polypropylene, developing a chlorinated modification product of metallocene polypropylene is expected to further broaden the application potential of polypropylene products. Summary of the Invention

[0003] Aiming at the deficiencies of the prior art, the present invention provides a metallocene-catalyzed chlorinated metallocene polypropylene and a preparation method thereof. The chlorinated metallocene polypropylene is a metallocene polypropylene obtained by metallocene catalysis, and then through chlorination modification, a chlorinated polymer modified with polar functional groups is obtained. The chlorinated metallocene polypropylene not only inherits the advantages of metallocene polypropylene but also has a certain polarity, has a wider resin compatibility, and can be applied to ink, coating, and gelling agent systems.

[0004] To achieve the above object, the first aspect of the present invention provides a preparation method of a metallocene-catalyzed chlorinated metallocene polypropylene, including the following steps: (1) Synthesis of metallocene-catalyzed polypropylene: Add a metallocene catalyst and propylene monomer to a high-pressure stirring kettle reactor, and simultaneously introduce hydrogen. Control the temperature and pressure. After reacting for 2 - 4 h, introduce ethanol for 0.5 - 1 h, filter, wash, and dry to obtain white metallocene polypropylene powder; (2) Pretreatment: The metallocene polypropylene powder obtained in step (1) is melt granulated by a twin-screw extruder, and then placed in a plasma generator for surface treatment for 5-10 min for standby. (3) Chlorination modification: The polypropylene particles pretreated in step (3) are dispersed in a glass jacketed reaction kettle with a mixed solvent, and chlorine gas is introduced while turning on the ultraviolet lamp. After stirring and reacting for 4-6 h, the introduction of chlorine gas is stopped. After adding a radical inhibitor for 0.5 h, filtration, washing, and vacuum drying are carried out to obtain chlorinated metallocene polypropylene.

[0005] In the present invention, a metallocene catalyst is used. It can coordinate with propylene monomers to form metal-carbon bonds, and then propylene monomers continue to be added to this growing chain to form a highly regular polypropylene chain and continuous polymerization. At the same time, the introduction of appropriate hydrogen gas can react with the active centers of the metallocene catalyst, preventing the chain from growing too long and obtaining a wide molecular weight distribution. And too long chains are likely to affect subsequent chlorination reactions; plasma treatment on the surface of polypropylene particles can enhance the content of surface active groups such as -COOH and -OH, and at the same time roughen the surface, improving the uniformity and contact efficiency of subsequent chlorination reactions; by controlling the conditions of chlorination modification, while effectively controlling the chlorine substitution degree, precise polarity regulation can be achieved, preventing the degradation of molecular chains and affecting the microstructure. The obtained chlorinated metallocene polypropylene not only inherits the advantages of narrow molecular weight distribution and small microcrystalline structure of metallocene polypropylene, but also has a certain polarity and has a wider resin compatibility.

[0006] Further, in step (1), the metallocene catalyst is a supported metallocene catalyst obtained by loading bis(cyclopentadienyl)zirconium dichloride on a silica carrier, and its dosage is 15-25% of the total amount of the propylene monomers. The supported metallocene catalyst used in this technical solution is Cp 2 ZrCl 2 -SiO 2 , and it can be activated with methylaluminoxane before use. In this way, the Zr center will be alkylated to form an active center, which is beneficial to the coordination with propylene monomers.

[0007] Further, in step (1), the reaction temperature is 70-80 °C, the pressure is 1-2 MPa, and the concentration of the hydrogen gas is controlled at 200-300 ppm; the dosage of ethanol is 1-5% of the total amount of the propylene monomers. Hydrogen gas is used as a chain transfer agent. By controlling its concentration, the molecular weight of the polymer can be precisely controlled, and at the same time, local overreaction during chlorination can be avoided. Ethanol is added after the reaction to terminate the polymerization reaction.

[0008] Further, in step (2), the extrusion temperature is 185-220 °C, and the granule diameter is 120-200 μm.

[0009] Furthermore, in step (2), the atmosphere in the plasma generator is argon, and the power is 100 - 120 W. The high electrons and ions generated by argon plasma will bombard the surface of polypropylene, causing the cleavage of C - H bonds. The generated free radicals react with oxygen or water to form oxygen - containing polar groups, improving the surface wettability, which is beneficial to the uniform adsorption of chlorine on the polypropylene surface and higher efficiency.

[0010] Furthermore, in step (3), the solid - liquid ratio of the polypropylene particles to the mixed solvent is 1:10 - 14; the mixed solvent is a mixture of carbon tetrachloride and dichloromethane with a volume ratio of 3 - 4:1; the flow rate of chlorine gas introduced is 0.3 - 0.5 L / min, the wavelength of the ultraviolet lamp is 254 nm, and the intensity is 80 mW / cm 2 , the reaction temperature ≤ 75 °C, and the stirring rate is 200 - 300 rpm. Dichloromethane has the characteristics of low boiling point, good dispersibility, high solubility for chlorine gas, and low toxicity. Adding an appropriate amount of dichloromethane to carbon tetrachloride can not only reduce the boiling point of the mixed solution, lower the reaction temperature, prevent the degradation of polypropylene, but also improve the contact efficiency between chlorine gas and the polypropylene chain, promote the extension of the substitution reaction into the particles, reduce the over - substitution caused by too high local chlorine concentration, and at the same time reduce the absorption of ultraviolet light and improve the photo - initiation efficiency. In this technical solution, by controlling the reaction conditions of chlorination modification, the chlorine substitution degree can be controlled between 15 - 30%, balancing the polarity and mechanical properties.

[0011] Furthermore, in step (3), the radical inhibitor is 2,6 - di - tert - butyl - p - cresol, and the addition amount is 0.1 - 0.2% of the total amount of the polypropylene particles.

[0012] Furthermore, in step (3), it is washed with ethanol 2 - 3 times, and the temperature of vacuum drying is 50 - 60 °C, and dried for 10 - 14 h.

[0013] Furthermore, in the above - mentioned technical solution, when introducing chlorine gas, 5 - 10% of the total amount of chlorine gas is mixed with oxygen at the same time. In this technical solution, when performing chlorination modification, mixing a small amount of oxygen at the same time will simultaneously introduce hydroxyl groups on the polypropylene chain, which can further improve the polarity of polypropylene and broaden its application range.

[0014] The second aspect of the present invention provides a chlorinated metallocene polypropylene prepared by the above - mentioned preparation method.

[0015] The beneficial effects of the present invention: The present invention combines metallocene polypropylene with chlorination modification technology. By using a metallocene catalyst and controlling the reaction conditions, polypropylene chains with high regularity are formed, and the molecular weight is controlled within 80,000 - 120,000. It has characteristics such as a narrow molecular weight distribution, small microcrystalline structure, superior impact strength and toughness. At the same time, after granulating the metallocene polypropylene, its surface is treated with plasma to enhance its surface active groups, which can improve the uniformity and contact efficiency of the subsequent chlorination reaction. Then, through chlorination modification and controlling various reaction conditions, while effectively controlling the chlorine substitution degree, precise regulation of the microstructure of metallocene polypropylene is achieved. While retaining its excellent properties, polarity is imparted. The obtained chlorinated metallocene polypropylene not only inherits the advantages of metallocene polypropylene such as a narrow molecular weight distribution and small microcrystalline structure, but also has a certain polarity and has a wider resin compatibility.

[0016] The preparation method of the present invention is simple, with low cost and can be industrially produced. The obtained chlorinated metallocene polypropylene has a wider resin compatibility and better solubility, and can be applied to more ink, coating and gelling agent systems, broadening the application scope of polypropylene materials. Detailed implementation mode

[0017] In order to better elaborate the technical solution of the present invention, the following will explain the solution of the present invention in combination with examples. Those skilled in the art will understand that the following examples are only used to illustrate the present invention and should not be regarded as limiting the scope of the present invention. For those not specified in the examples regarding specific technologies or conditions, the technologies described in the literature or reference books in this field are followed or according to the product instructions. For reagents or instrument equipment without indicating the manufacturer, they are all conventional products.

[0018] All the above technical features of the present invention can be combined with the technical features specifically described below (such as in the examples) to form new or preferred technical solutions.

[0019] The following further describes the present invention in detail in combination with examples: Example 1 A preparation method of chlorinated metallocene polypropylene based on metallocene catalysis, comprising the following steps: (1) Synthesis of metallocene-catalyzed polypropylene: Add propylene monomer to a high-pressure stirred tank reactor, start stirring, and then add 15% of the total amount of propylene monomer of the metallocene catalyst Cp 2 ZrCl 2 -SiO 2 (activated with methylaluminoxane first), then introduce hydrogen (concentration controlled at 200 ppm), control the temperature at 80 °C and the pressure at 1 MPa. After reacting for 2 h, introduce 2% of the total amount of propylene monomer of ethanol for 1 h, then filter and wash (wash 3 times with ethanol), and dry to obtain metallocene polypropylene powder; (2) Pretreatment: The metallocene polypropylene powder obtained in step (1) is melt granulated by a twin-screw extruder, where the extrusion temperature is 185 °C, and the particle size after granulation is 120 - 200 μm. Then it is put into a plasma generator and surface-treated in an argon atmosphere at 100 W for 10 min for standby; (3) Chlorination modification: The polypropylene particles pretreated in step (3) are dispersed in a glass jacketed reactor containing a mixed solvent (volume ratio of carbon tetrachloride to dichloromethane is 3:1) according to a solid-liquid ratio of 1:10. Meanwhile, chlorine gas is introduced at a flow rate of 0.3 L / min, and ultraviolet light irradiation is turned on (wavelength 254 nm, intensity 80 mW / cm 2 ), after stirring and reacting at 200 rpm for 6 h (reaction temperature 65 °C), the introduction of chlorine gas is stopped. After adding 2,6-di-tert-butyl-p-cresol accounting for 0.1% of the total amount of polypropylene particles for 0.5 h, filtration and washing (elution with ethanol 3 times) are carried out, and vacuum drying is carried out at 50 °C for 14 h to obtain chlorinated metallocene polypropylene.

[0020] Example 2 A preparation method of chlorinated metallocene polypropylene based on metallocene catalysis, comprising the following steps: (1) Synthesis of metallocene-catalyzed polypropylene: Propylene monomer is added to a high-pressure stirred tank reactor, stirring is started, and then a metallocene catalyst Cp 2 ZrCl 2 -SiO 2 (activated with methylaluminoxane first) is added, and then hydrogen gas is introduced (concentration controlled at 250 ppm), the temperature is controlled at 75 °C, the pressure is 1.5 MPa, after reacting for 3 h, ethanol accounting for 3% of the total amount of propylene monomer is introduced for 0.5 h, filtration and washing (washing with ethanol 3 times) are carried out, and after drying, metallocene polypropylene powder is obtained; (2) Pretreatment: The metallocene polypropylene powder obtained in step (1) is melt granulated by a twin-screw extruder, where the extrusion temperature is 200 °C, and the particle size after granulation is 120 - 200 μm. Then it is put into a plasma generator and surface-treated in an argon atmosphere at 110 W for 8 min for standby; (3) Chlorination modification: The polypropylene particles pretreated in step (3) are dispersed in a glass jacketed reactor containing a mixed solvent (volume ratio of carbon tetrachloride to dichloromethane is 3:1) according to a solid-liquid ratio of 1:12. Meanwhile, chlorine gas is introduced at a flow rate of 0.4 L / min, and ultraviolet light irradiation is turned on (wavelength 254 nm, intensity 80 mW / cm 2 ), after stirring and reacting at 250 rpm for 5 h (reaction temperature 70 °C), the introduction of chlorine gas is stopped. After adding 2,6-di-tert-butyl-p-cresol accounting for 0.1% of the total amount of polypropylene particles for 0.5 h, filtration and washing (elution with ethanol 2 - 3 times) are carried out, and vacuum drying is carried out at 55 °C for 12 h to obtain chlorinated metallocene polypropylene.

[0021] Example 3 A preparation method of metallocene-catalyzed chlorinated metallocene polypropylene, comprising the following steps: (1) Synthesis of metallocene-catalyzed polypropylene: Add propylene monomer into a high-pressure stirred autoclave reactor, start stirring, and then add 25% of the total amount of propylene monomer of the metallocene catalyst Cp 2 ZrCl 2 -SiO 2 (activated with methylaluminoxane first), then introduce hydrogen (concentration controlled at 300 ppm), control the temperature at 70 °C and the pressure at 1 MPa, after reacting for 4 h, introduce 0.5 h of ethanol accounting for 5% of the total amount of propylene monomer, filter and wash (wash with ethanol 3 times), and obtain white metallocene polypropylene powder after drying; (2) Pretreatment: Melt and granulate the metallocene polypropylene powder obtained in step (1) through a twin-screw extruder, wherein the extrusion temperature is 220 °C, the particle size after granulation is 120-200 μm, and then put it into a plasma generator for surface treatment at 120 W in an argon atmosphere for 5 min for standby; (3) Chlorination modification: Disperse the polypropylene particles pretreated in step (3) in a glass-jacketed reactor added with a mixed solvent (volume ratio of carbon tetrachloride to dichloromethane is 4:1) according to a solid-liquid ratio of 1:14, and at the same time introduce chlorine gas at a flow rate of 0.5 L / min, turn on the ultraviolet lamp irradiation (wavelength 254 nm, intensity 80 mW / cm 2 ), after stirring and reacting at 300 rpm for 4 h (reaction temperature 75 °C), stop introducing chlorine gas, add 2,6-di-tert-butyl-p-cresol accounting for 0.2% of the total amount of polypropylene particles after 0.5 h, filter, wash (elute with ethanol 3 times), and vacuum dry at 60 °C for 10 h to obtain chlorinated metallocene polypropylene.

[0022] Example 4 A preparation method of metallocene-catalyzed chlorinated metallocene polypropylene, comprising the following steps: (1) Synthesis of metallocene-catalyzed polypropylene: Add propylene monomer into a high-pressure stirred autoclave reactor, start stirring, and then add 25% of the total amount of propylene monomer of the metallocene catalyst Cp 2 ZrCl 2 -SiO 2 (activated with methylaluminoxane first), then introduce hydrogen (concentration controlled at 300 ppm), control the temperature at 70 °C and the pressure at 1 MPa, after reacting for 4 h, introduce 0.5 h of ethanol accounting for 5% of the total amount of propylene monomer, filter and wash (wash with ethanol 3 times), and obtain white metallocene polypropylene powder after drying; (2) Pretreatment: The metallocene polypropylene powder obtained in step (1) is melt granulated by a twin-screw extruder, where the extrusion temperature is 220 °C, the particle size after granulation is 120 - 200 μm, and then it is placed in a plasma generator for surface treatment with argon atmosphere at 120 W for 5 min and set aside; (3) Chlorination modification: The pretreated polypropylene particles in step (3) are dispersed in a glass jacketed reactor with a mixed solvent (volume ratio of carbon tetrachloride to dichloromethane is 4:1) according to a solid-liquid ratio of 1:14. At the same time, chlorine gas is introduced at a flow rate of 0.5 L / min and oxygen gas is introduced at a flow rate of 0.025 L / min. Then, turn on the ultraviolet lamp irradiation (wavelength 254 nm, intensity 80 mW / cm 2 ), stir and react at 300 rpm for 4 h, then stop introducing chlorine gas. After adding 2,6-di-tert-butyl-p-cresol accounting for 0.2% of the total amount of polypropylene particles for 0.5 h (reaction temperature 75 °C), filter, wash (elute 3 times with ethanol), and vacuum dry at 60 °C for 10 h to obtain the stereoisomer.

[0023] Comparative Example 1 A preparation method of polypropylene, different from Example 3 in that: in step (1), the catalyst used is titanium tetrachloride.

[0024] Comparative Example 2 A preparation method of chlorinated metallocene polypropylene based on metallocene catalysis, different from Example 3 in that: in step (1), hydrogen gas is not introduced.

[0025] Comparative Example 3 A preparation method of chlorinated metallocene polypropylene based on metallocene catalysis, different from Example 3 in that: in step (2), no plasma treatment is performed after granulation.

[0026] Comparative Example 4 A preparation method of chlorinated metallocene polypropylene based on metallocene catalysis, different from Example 3 in that: in step (3), the reaction temperature is 90 °C.

[0027] Comparative Example 5 A preparation method of chlorinated metallocene polypropylene based on metallocene catalysis, different from Example 3 in that: in step (3), the reaction solvent is pure carbon tetrachloride.

[0028] Comparative Example 6 A preparation method of chlorinated metallocene polypropylene based on metallocene catalysis, different from Example 3 in that: in step (3), the chlorine gas flow rate is 0.7 L / min.

[0029] Test Example 1 The molecular weight, distribution index (PDI) of the metallocene polypropylene powders prepared in Experimental Examples 1-4 and Comparative Examples 1-6, as well as the chlorine substitution rate, solubility, and adhesion of the chlorinated metallocene polypropylene were tested, and the results are shown in Table 1. Among them, the chlorine content was tested by X-ray photoelectron spectroscopy, and the solubility was obtained by dissolving 1 g of the sample in 10 mL of DMF, stirring at 25 °C for 2 h, filtering the undissolved matter; the adhesion was tested by coating the chlorinated metallocene polypropylene on a PP substrate according to the ASTM D3359 standard.

[0030] Table 1 Performance Test

[0031] From the results in Table 1, it can be seen that the metallocene polypropylene obtained by first using metallocene to catalyze polypropylene in the preparation method of the present invention has a narrow molecular weight distribution and high stereoregularity, with PDI < 2.5, providing a framework for subsequent chlorination. The final obtained chlorinated metallocene polypropylene has a chlorine substitution rate between 18.5 - 26.8, a solubility greater than 23.4%, and an adhesion above 3B, which can meet the application requirements of ink, coating, and gelling agent systems.

[0032] In Comparative Example 1, the polypropylene obtained by using a common catalyst has a wide molecular weight distribution, which easily affects the uniformity of subsequent chlorine substitution and thus affects solubility and mechanical properties; in Comparative Example 2, no hydrogen is added during the metallocene-catalyzed polypropylene process, and its chain is prone to grow too long, also resulting in a wide molecular weight distribution and affecting the subsequent reaction and properties; in Comparative Example 3, the metallocene polypropylene is not surface-treated after being obtained, resulting in a decrease in chlorination efficiency and uniformity, and also affecting the chlorine substitution degree and properties to a certain extent; in Comparative Example 4, the chlorination reaction temperature is too high, which easily causes the polypropylene to degrade and affects its properties; in Comparative Example 5, the solvent for the chlorination reaction is pure carbon tetrachloride. Due to its relatively high boiling point, large solvent loss, and relatively large fluctuations on the surface and inside of chlorine substitution, it is uneven, directly affecting the overall chlorine substitution degree and subsequent properties; in Comparative Example 6, the chlorine gas flow rate is too high, resulting in too high a chlorine substitution degree, which is not suitable for inks, coatings, and gelling agents.

[0033] Finally, it should be emphasized that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for preparing metallocene chlorinated polypropylene based on metallocene catalysis, characterized in that: The following steps are involved: (1) Synthesis of metallocene-catalyzed polypropylene: Add metallocene catalyst and propylene monomer into a high-pressure stirred tank reactor, introduce hydrogen at the same time, control the temperature and pressure, react for 2-4 hours, introduce ethanol for 0.5-1 hour, filter, wash, and dry to obtain metallocene polypropylene powder; (2) Pretreatment: The metallocene polypropylene powder obtained in step (1) is melt-granulated by a twin-screw extruder, and then placed in a plasma generator for surface treatment for 5-10 minutes, and then set aside; (3) Chlorination modification: The polypropylene particles pretreated in step (3) are dispersed in a glass jacketed reactor containing a mixed solvent, and chlorine gas is introduced at the same time. The ultraviolet lamp is turned on. After stirring for 4-6 hours, the introduction of chlorine gas is stopped. A free radical inhibitor is added for 0.5 hours, and then filtered, washed, and vacuum dried to obtain chlorinated metallocene polypropylene.

2. The method for preparing metallocene chlorinated polypropylene based on metallocene catalysis according to claim 1, characterized in that: In step (1), the metallocene catalyst is a supported metallocene catalyst obtained by supporting bis(cyclopentadienyl)zirconium dichloride on a silica carrier, and its usage is 15-25% of the total amount of the propylene monomer.

3. The method for preparing metallocene chlorinated polypropylene based on metallocene catalysis according to claim 1, characterized in that: In step (1), the reaction temperature is 70-80° C., the pressure is 1-2 MPa, the concentration of the hydrogen is controlled at 200-300 ppm; and the amount of the ethanol used is 1-5% of the total amount of the propylene monomer.

4. The method for preparing metallocene chlorinated polypropylene based on metallocene catalysis according to claim 1, characterized in that: In step (2), the extrusion temperature is 185-220°C, and the granulation particle size is 120-200 μm.

5. The method for preparing metallocene chlorinated polypropylene based on metallocene catalysis according to claim 1, characterized in that: In step (2), the plasma generator is filled with argon atmosphere and has a power of 100-120W.

6. The method for preparing metallocene chlorinated polypropylene based on metallocene catalysis according to claim 1, characterized in that: In step (3), the solid-liquid ratio of the polypropylene particles to the mixed solvent is 1:10-14; the mixed solvent is a mixture of carbon tetrachloride and dichloromethane in a volume ratio of 3-4:1; the flow rate of the chlorine gas is 0.3-0.5 L / min, the wavelength of the ultraviolet lamp is 254 nm, and the intensity is 80 mW / cm 2 , reaction temperature ≤75°C, stirring rate 200-300rpm.

7. The method for preparing metallocene chlorinated polypropylene based on metallocene catalysis according to claim 1, characterized in that: In step (3), the free radical inhibitor is 2,6-di-tert-butyl-p-cresol, and the amount added is 0.1-0.2% of the total amount of the polypropylene particles.

8. The method for preparing metallocene chlorinated polypropylene based on metallocene catalysis according to claim 1, characterized in that: In step (3), ethanol is used for washing 2-3 times, and the vacuum drying temperature is 50-60° C. and the drying time is 10-14 h.

9. The method for preparing metallocene chlorinated polypropylene based on metallocene catalysis according to claim 1, characterized in that: When chlorine is introduced, 5-10% of the total amount of chlorine is mixed with oxygen.

10. A chlorinated metallocene polypropylene prepared by the preparation method according to any one of claims 1 to 9.

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