Polypropylene copolymer having high transparency and toughness

Abstract

A polypropylene polymer composition having excellent impact strength and, optionally in combination with excellent rigidity, a high transmittance is provided, along with a method for manufacturing such a composition. Such a polypropylene polymer composition also has a low melt flow rate (e.g., 5 g / 10 min or less or 4 g / 10 min or less).

Description

Technical Field

[0001] Cross - reference to Related Applications

[0001] This application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 344,193, filed on May 20, 2022, which is hereby incorporated by reference in its entirety for all purposes.

[0002]

[0002] This technology generally relates to polypropylene polymer compositions having an improved balance of properties. More particularly, the polypropylene polymer compositions exhibit high transparency and toughness.

Background Art

[0003]

[0003] Polyolefins such as polypropylene are used in a variety of demanding applications. Thus, there is an ongoing search for specially tailored polymers that can meet the requirements of these applications. For example, heterophasic systems are known for their good impact behavior. Such heterophasic propylene copolymers include a crystalline matrix that is either a propylene homopolymer or a random propylene copolymer in which an elastomeric copolymer such as a propylene / ethylene copolymer is dispersed.

Summary of the Invention

Means for Solving the Problems

[0004]

[0004] This disclosure provides a polypropylene composition comprising a heterophasic propylene copolymer having high transparency and high stiffness / toughness, as well as a corresponding method for preparing such a composition. Such polypropylene compositions have an improved balance of properties beyond those disclosed in the prior art and are suitable for use in thermoforming and extrusion blow molding applications.

[0005]

[0005] Generally, the present disclosure is directed to polypropylene polymer compositions having an improved balance of properties. The polypropylene polymer compositions produced in accordance with the present disclosure can be formulated, for example, to have a high transmission rate in combination with excellent impact strength. For example, the polymer compositions described herein have a relatively low haze while having excellent toughness. Further, these polymer compositions can also exhibit excellent rigidity.

[0006]

[0006] The polypropylene polymer compositions described herein are prepared by combining a first polymer phase comprising a polypropylene homopolymer or a combined random copolymer with a second polymer phase comprising a rubbery propylene / ethylene copolymer. The selection of specific parameters for each polymer phase described herein provides a polypropylene polymer composition having high transmission rate in combination with excellent impact strength and optionally excellent rigidity.

[0007]

[0007] In one aspect, a polypropylene composition comprising: (a) a first polymer phase comprising a polypropylene homopolymer or random copolymer, said polypropylene homopolymer or random copolymer optionally containing one or more comonomers in an amount of about 3 wt% or less based on the total weight of the propylene homopolymer or copolymer, having a total low temperature xylene soluble content of about 2 wt% to about 6 wt%, and having a melt flow rate of about 0.5 g / 10 min to about 3 g / 10 min; and (b) a second polymer phase comprising a propylene / ethylene copolymer, said propylene / ethylene copolymer containing ethylene in an amount of less than about 18 wt% based on the total weight of the propylene / ethylene copolymer; and wherein the ratio of the melt flow rate of the polypropylene homopolymer or random copolymer to the melt flow rate of the propylene / ethylene copolymer is greater than about 1.0. The first polymer phase and the second polymer phase combine to provide the polypropylene composition having a melt flow rate of about 4 g / 10 min or less, an ethylene content of less than about 5 wt%, a total low temperature xylene soluble content of about 5 wt% to about 20 wt%, a haze at 1 mm of less than about 20%, an Izod impact strength at 23°C of more than about 500 J / m, a Gardner falling impact strength at 0°C of more than about 17 Nm (150 inch-pounds), and a flexural modulus of about 800 MPa or more. A polypropylene composition is provided.

[0008]

[0008] In some embodiments, the first polymer phase includes a crystalline matrix including a polypropylene homopolymer or random copolymer. In some embodiments, the polypropylene composition includes a heterophasic propylene copolymer.

[0009]

[0009] In some embodiments, the first polymer phase includes a polypropylene homopolymer or random copolymer, and the polypropylene homopolymer or random copolymer includes one or more comonomers in an amount of about 0 wt% to about 3 wt% based on the total weight of the propylene homopolymer or copolymer. In some embodiments, the first polymer phase includes a polypropylene homopolymer or random copolymer having a total low temperature xylene soluble content of about 2.5 wt% or about 4.8 wt%. In some embodiments, the first polymer phase includes a polypropylene homopolymer or random copolymer having a melt flow rate of about 0.5 g / 10 min to about 1.5 g / 10 min. In some embodiments, the propylene / ethylene copolymer present in the second polymer phase includes butene.

[0010] In some embodiments, the polypropylene composition has a melt flow rate of from about 0.5 g / 10 min to about 1.5 g / 10 min. In some embodiments, the polypropylene composition has an ethylene content of from about 2 wt% to about 4.5 wt%. The polypropylene composition has a total low temperature xylene soluble content of about 7 wt% or about 12 wt%. In some embodiments, the polypropylene composition has a haze at 1 mm of from about 5% to about 15%. In some embodiments, the polypropylene composition has an Izod impact strength at 23 °C of from about 500 J / m to about 900 J / m. In some embodiments, the polypropylene composition has a Gardner drop impact strength at 0 °C of from about 17 Nm (150 inch - pounds) to about 39.6 Nm (350 inch - pounds). In some embodiments, the polypropylene composition has a flexural modulus of from about 800 MPa to about 1300 MPa.

[0011]

[0011] In another aspect, a polypropylene composition, (a) a first polymer phase comprising a polypropylene homopolymer or random copolymer, said polypropylene homopolymer or random copolymer optionally comprising one or more comonomers in an amount of about 1 wt% or less based on the total weight of the propylene homopolymer or copolymer, having a total low temperature xylene soluble content of less than about 4 wt%, and having a melt flow rate of from about 2 g / 10 min to about 5 g / 10 min; (b) a second polymer phase comprising a propylene / ethylene copolymer, said propylene / ethylene copolymer comprising ethylene in an amount of less than about 18 wt% based on the total weight of the propylene / ethylene copolymer; comprising, wherein the ratio of the melt flow rate of the polypropylene homopolymer or random copolymer to the melt flow rate of the propylene / ethylene copolymer is greater than about 1.0, The first polymer phase and the second polymer phase combine to provide the polypropylene composition having a melt flow rate of about 5 g / 10 min or less, an ethylene content of less than about 3.5 wt%, a total low temperature xylene soluble content of about 5 wt% to about 15 wt%, a haze at 1 mm of less than about 20%, an Izod impact strength at 23° C. of more than about 200 J / m, and a flexural modulus of about 1100 MPa or more. A polypropylene composition is provided.

[0012]

[0012] In some embodiments, the first polymer phase comprises a polypropylene homopolymer or random copolymer, the polypropylene homopolymer or random copolymer comprising one or more comonomers in an amount of about 0.5 wt% to about 1 wt% based on the total weight of the propylene homopolymer or copolymer. In some embodiments, the first polymer phase comprises a polypropylene homopolymer or random copolymer and has a total low temperature xylene soluble content of about 1 wt% to about 3 wt%. In some embodiments, the first polymer phase comprises a polypropylene homopolymer or random copolymer and has a melt flow rate of about 2 g / 10 min to about 4 g / 10 min. In some embodiments, the propylene / ethylene copolymer present in the second polymer phase comprises butene.

[0013]

[0013] In some embodiments, the polypropylene composition has a melt flow rate of about 2 g / 10 min to about 4 g / 10 min. In some embodiments, the polypropylene composition has an ethylene content of about 2 wt% to about 3.5 wt%. In some embodiments, the polypropylene composition has a total low temperature xylene soluble content of about 5.5 wt% or about 12 wt%. In some embodiments, the polypropylene composition has a haze at 1 mm of about 10% to about 20%. In some embodiments, the polypropylene composition has an Izod impact strength at 23° C. of about 200 J / m to about 900 J / m. In some embodiments, the polypropylene composition has a flexural modulus of about 1200 MPa to about 1600 MPa.

[0014]

[0014] In any embodiment, the second polymer phase comprises a propylene / ethylene copolymer comprising ethylene in an amount of from about 10 wt% to about 18 wt% based on the total weight of the propylene / ethylene copolymer.

[0015]

[0015] In any embodiment, the ratio of the melt flow rate of the polypropylene homopolymer or random copolymer to the melt flow rate of the propylene / ethylene copolymer is from about 1.0 to about 3.0.

[0016]

[0016] In any embodiment, the polypropylene composition has a Gardner impact strength at 23 °C greater than about 17 Nm (150 inch-pounds).

[0017] In any embodiment, the polypropylene composition further comprises one or more of a nucleating agent, an antacid, and an antioxidant. In some embodiments, the one or more nucleating agents are present in an amount of about 5000 ppm or less.

[0017]

[0018] In any embodiment, the one or more comonomers present in the polypropylene homopolymer or random copolymer comprise ethylene.

[0019] In another aspect, there is provided a molded article formed from any one of the polypropylene compositions described herein. In some embodiments, the molded article is an extrusion blow molded article.

[0018]

[0020] Also, in another aspect, a method of preparing any one of the polypropylene compositions described herein by sequential polymerization in the presence of a Ziegler-Natta catalyst comprising preparing a first polymer phase in a first gas phase reactor, transferring the first polymer phase to a second gas phase reactor comprising a second polymer phase, and comprising, A method is provided that results in a polypropylene composition by combining a first polymer phase with a second polymer phase.

[0019]

[0021] Also, in another aspect, a method for preparing any one of the polypropylene compositions described herein, comprising: supplying propylene and optionally one or more comonomers to a first reactor, and supplying a catalyst mixture comprising (1) a Ziegler-Natta catalyst, (2) a cocatalyst, and (3) an external donor to the first reactor; contacting propylene with the catalyst mixture under first polymerization conditions to polymerize propylene and optionally one or more comonomers to form a first polymer phase comprising a propylene homopolymer or copolymer; transferring at least a portion of the first polymer phase to a second reactor; supplying additional propylene and ethylene to the second reactor to form a second polymer phase; and A method is provided that results in a polypropylene composition by combining a first polymer phase with a second polymer phase.

[0020]

[0022] Other features and aspects of the disclosure are discussed in more detail below.

DETAILED DESCRIPTION OF THE INVENTION

[0021]

[0023] Various embodiments are described below. It should be noted that specific embodiments are not intended as an exhaustive description or as a limitation to the broader aspects discussed herein. One aspect described in connection with a particular embodiment is not necessarily limited to that embodiment and can be implemented using any other embodiment(s).

[0022]

[0024] As used herein, "about" is understood by those of ordinary skill in the art and varies to some extent depending on the context in which it is used. Even in the context in which this term is used, if this term is not obvious to those of ordinary skill in the art, "about" means up to plus or minus 10% of that particular term.

[0023]

[0025] The use of the terms "a", "an", "the", and similar indicators in the context of describing elements (especially in the context of the following claims) should be construed to apply to both the singular and the plural, unless otherwise indicated herein or clearly contradicted by the context. The recitation of a range of values herein is merely intended to function as a shorthand method of referring individually to each separate value that falls within that range, and each separate value is hereby incorporated herein as if it were individually recited herein. All methods described herein may be performed in any suitable order, unless otherwise indicated herein or otherwise clearly contradicted by the context. The use of any and all example or exemplary syntax (e.g., "such as") provided herein is merely intended to better clarify embodiments and does not otherwise limit the claims unless otherwise expressly stated. No syntax in this specification should be construed as indicating any essential element.

[0024]

[0026] Generally, an alkyl, alkenyl, aryl or ether group (e.g., an alkyl group) as defined below, in which one or more bonds to a hydrogen atom contained therein are replaced by bonds to non-hydrogen or non-carbon atoms, may be substituted. The substituents also include groups in which one or more bonds to carbon(s) or hydrogen(s) atom(s) are replaced by one or more bonds to a heteroatom, including double or triple bonds. Thus, unless otherwise specified, the substituents are substituted with one or more substituents. In some embodiments, the substituents are substituted with 1, 2, 3, 4, 5 or 6 substituents. Examples of substituents include halogen (i.e., F, Cl, Br and I); hydroxyl; alkoxy, alkenoxy, alkynoxy, aryloxy, aralkyloxy, heterocyclyloxy and heterocyclylalkoxy groups; carbonyl (oxo); carboxyl; ester; urethane; oxime; hydroxylamine; alkoxyamine; aralkoxyamine; thiols; sulfide; sulfoxide; sulfone; sulfonyl; sulfonamide; amine; N-oxide; hydrazine; hydrazide; hydrazone; azide; amide; urea; amidine; guanidine; enamine; imide; isocyanate; isothiocyanate; cyanate; thiocyanate; imine; nitro group; nitrile (i.e., CN), etc.

[0025]

[0027] As used herein, an "alkyl" group includes straight and branched alkyl groups having from 1 to about 20 carbon atoms, typically from 1 to 12 carbons, or in some embodiments from 1 to 8 carbon atoms. As used herein, an "alkyl group" includes cycloalkyl groups as defined below. The alkyl group may be substituted or unsubstituted. The alkyl group may be substituted one or more times. The alkyl group may be substituted two or more times. Examples of straight chain alkyl groups include methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, and n-octyl groups. Examples of branched alkyl groups include, but are not limited to, isopropyl, sec-butyl, t-butyl, neopentyl, isopentyl groups, and 1-cyclopentyl-4-methylpentyl. Representative substituted alkyl groups may be substituted one or more times, for example, with amino, thio, hydroxy, cyano, alkoxy, and / or halo groups such as F, Cl, Br and I groups. As used herein, the term haloalkyl is an alkyl group having one or more halo groups. In some embodiments, haloalkyl refers to a perhaloalkyl group.

[0026]

[0028] An alkenyl group is a straight, branched or cyclic alkyl group having from 2 to about 20 carbon atoms and further comprising at least one double bond. In some embodiments, the alkenyl group has from 1 to 12 carbons, or typically from 1 to 8 carbon atoms. The alkenyl group may be substituted or unsubstituted. The alkenyl group includes, inter alia, for example, vinyl, propenyl, 2-butenyl, 3-butenyl, isobutenyl, cyclohexenyl, cyclopentenyl, cyclohexadienyl, butadienyl, pentadienyl, and hexadienyl groups. The alkenyl group may likewise be substituted with an alkyl group. A divalent alkenyl group, i.e., an alkenyl group having two bonding sites, includes, but is not limited to, CH-CH=CH 2 , C=CH 2 , or C=CHCH 3 .

[0027]

[0029] As used herein, an "aryl" or "aromatic" group is a cyclic aromatic hydrocarbon that does not contain heteroatoms. Aryl groups include monocyclic, bicyclic, and polycyclic ring systems. In this way, aryl groups include, but are not limited to, phenyl, azulenyl, heptalenyl, biphenylenyl, indacenyl, fluorenyl, phenanthrenyl, triphenylenyl, pyrenyl, naphthacenyl, chrysenyl, biphenyl, anthracenyl, indenyl, indanyl, pentalenyl, and naphthyl groups. An aryl group having one or more alkyl groups may also be referred to as an alkaryl group. In some embodiments, the aryl group contains 6-14 carbon atoms in the ring portion of the group, 6-12 in others, and 6-10 carbon atoms further. The phrase "aryl group" includes groups containing fused rings, such as fused aromatic aliphatic ring systems (e.g., indanyl, tetrahydronaphthyl, etc.). The aryl group may be substituted or unsubstituted.

[0028]

[0030] The term "alkoxy" group refers to an (alkyl)O-- group where alkyl is as defined herein.

[0031] The term "cycloalkyl" refers to a monocyclic or polycyclic aliphatic, non-aromatic group in which each of the atoms forming the ring (i.e., the backbone atoms) is a carbon atom. In some embodiments, the cycloalkyl is a spirocyclic or bridged compound. In some embodiments, the cycloalkyl is optionally fused to an aromatic ring, and the location of the bond is at a carbon that is not an aromatic ring carbon atom. Cycloalkyl groups include groups having 3-10 ring atoms. In some embodiments, the cycloalkyl group is selected from cyclopropyl, cyclobutyl, cyclopentyl, cyclopentenyl, cyclohexyl, cyclohexenyl, cycloheptyl, cyclooctyl, spiro[2.2]pentyl, norbornyl, and bicyclo[1.1.1]pentyl. In some embodiments, the cycloalkyl is C 3 -C 6It is cycloalkyl. In some embodiments, the cycloalkyl is a monocyclic cycloalkyl. Monocyclic cycloalkyls include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl. Polycyclic cycloalkyls include, for example, adamantyl, norbornyl (i.e., bicyclo[2.2.1]heptanyl), norbornenyl, decalinyl, 7,7-dimethyl-bicyclo[2.2.1]heptanyl, and the like.

[0029]

[0032] As used herein, the term "propylene / ethylene copolymer" is a copolymer containing a majority weight percent of propylene monomer with ethylene monomer as a secondary component and does not exhibit a distinct melting peak. A random copolymer is a polymer having individual repeating units of comonomers present in a random or statistical distribution in the polymer chain and can be defined as crystalline exhibiting a distinct melting peak.

[0030]

[0033] As used herein, the melt flow rate (MFR) for propylene-based polymers is measured at 230 °C using a 2.16 kg weight in accordance with the ASTM D1238 test method. When a sample before pelletization (powder MFR) is measured, the polymer is mixed with an antioxidant and an acid neutralizer in a manner known to those skilled in the art prior to measuring the MFR to avoid degradation during measurement.

[0031]

[0034] Low temperature xylene soluble (XS) is defined as the weight percent of resin remaining in the solution after a sample of polypropylene resin is dissolved in hot xylene and the solution is cooled to 25 °C. This is also referred to as the weight measurement XS method according to ASTM D5492-98 using a precipitation time of 90 minutes and is also referred to herein as the "wet method". The procedure consists of weighing a 2 g sample and dissolving the sample in 200 ml of o-xylene in a 400 ml flask having a 24 / 40 joint. The flask is connected to a water condenser, the contents are stirred and heated to nitrogen (N 2)It is refluxed below and then the reflux is maintained for an additional 30 minutes. Then the solution is cooled at 25 °C in a temperature-controlled water bath for 90 minutes to allow crystallization of the xylene-insoluble fraction. Once the solution is cooled, the insoluble fraction precipitates from the solution and separation of the xylene-soluble fraction (XS) from the xylene-insoluble portion (XI) is achieved by filtration through a 25-micron filter paper. 100 ml of the filtrate is collected into a pre-weighed aluminum dish and the o-xylene evaporates from this 100 ml of filtrate under a nitrogen stream. Once the solvent has evaporated, the dish and its contents are placed in a vacuum oven at 100 °C for 30 minutes or until dry. Then the dish is allowed to cool to room temperature and weighed. The xylene-soluble portion is calculated as XS (wt %) = [(m 3 -m 2 ) * 2 / m 1 ) * 100 (where m 1 is the original weight of the sample used, m 2 is the weight of the empty aluminum dish, and m 3 is the weight of the dish and the residue) (where the asterisk, * in this formula and elsewhere in the present disclosure indicates multiplying the specified term or value). XS can also be measured according to the Viscotek method as follows. 0.4 g of the polymer is dissolved in 20 ml of xylene while stirring at 130 °C for 60 minutes. Then the solution is cooled to 25 °C and after 90 minutes, the insoluble polymer fraction is filtered off. The resulting filtrate is analyzed by Flow Injection Polymer Analysis using a Viscotek ViscoGEL H-100-3078 column with a THF mobile phase flowing at 1.0 ml / min. The column is connected to a Viscotek Model 302 Triple Detector Array having a light scattering, viscometer and refractometer detector operating at 45 °C. Instrument calibration is maintained using a Viscotek PolyCAL™ polystyrene standard. Homopolymers, such as Dow 5D98, are used as reference materials to confirm that the Viscotek instrument wet method defined in the following paragraph gives the same results and can therefore be used interchangeably.

[0032]

[0035] The ethylene content of either the random ethylene copolymer or the ethylene / propylene copolymer is measured using Fourier transform infrared spectroscopy (FTIR) which is correlated to the ethylene value determined using 13 13 13C NMR as the primary method. The relationship and agreement between the measurements made using the two methods are described, for example, in J.R. Paxson, J.C. Randall, “Quantitative Measurement of Ethylene Incorporation into Propylene Copolymers by Carbon-13 Nuclear Magnetic Resonance and Infrared Spectroscopy”, Analytical Chemistry, Vol. 50, No. 13, November 13, 1978, pages 1777 - 1780.

[0033]

[0036] The MFR of the second phase was calculated using the following formula.

[0034]

Equation

[0035] Wherein, MFR P2 refers to the MFR of the ethylene / propylene copolymer produced in the second phase, MFR c refers to the MFR of the composition measured before pelletization (powder MFR), MFR P1 refers to the MFR of the first phase, and f 1 refers to the amount of phase 1 in the composition.

[0036]

[0037] The flexural modulus is determined using Type 1 test specimens according to ASTM 3641, molded according to ASTM D4101 at 1.3 mm / min according to ASTM D790 - 10 Method A.

[0037]

[0038] The Izod impact strength is measured on specimens molded according to ASTM D4101 according to ASTM D256.

[0039] The Gardner impact test is measured according to ASTM D5420.

[0038]

[0040] Haze is measured using BYK Gardner Haze-Gard Plus 4725 on injection molded specimens with a thickness of 1 mm according to ASTM test D1003 procedure A. Polypropylene polymer composition

[0041] The present disclosure relates to polypropylene polymer compositions having an improved balance of properties such as high transmittance, in combination with excellent impact strength and optionally excellent rigidity. These polypropylene polymer compositions also have a low melt flow rate (e.g., 5 g / 10 min or less or 4 g / 10 min or less). Such polypropylene polymer compositions described herein include a heterophasic polypropylene copolymer, which is prepared by combining a first polymer phase comprising a polypropylene homopolymer or a combined random copolymer with a second polymer phase comprising a rubbery propylene / ethylene copolymer. The selection of specific parameters of each polymer phase described herein provides a polypropylene polymer composition having high transmittance in combination with excellent impact strength (especially at room temperature) and optionally excellent rigidity. In particular, the polypropylene polymer compositions described herein have a low haze of less than about 20%, an Izod impact strength at 23 °C of greater than about 200 J / m, and a flexural modulus of at least about 800 MPa.

[0039]

[0042] To achieve a polypropylene polymer composition having a low melt flow rate with excellent impact strength and, optionally, high rigidity in combination with high transmittance, it is recognized that a specific combination of parameters described for the first and second polymer phases is required. In particular, a low to nil content rate of one or more comonomers (e.g., ethylene content) in the first polymer phase, and a low ethylene content (less than 18 wt%) in the second polymer phase provide high rigidity / toughness and high transparency. Such parameters provide a polypropylene composition having a low ethylene content (e.g., less than about 5 wt%).

[0040]

[0043] The polypropylene composition described herein may have high transparency and high toughness. In one aspect, a polypropylene composition comprising (a) a first polymer phase comprising a polypropylene homopolymer or random copolymer, said polypropylene homopolymer or random copolymer optionally comprising one or more comonomers in an amount of about 3 wt% or less based on the total weight of the propylene homopolymer or copolymer, having a total cold xylene soluble content of about 2 wt% to about 6 wt%, and having a melt flow rate of about 0.5 g / 10 min to about 3 g / 10 min, a first polymer phase; (b) a second polymer phase comprising a propylene / ethylene copolymer, said propylene / ethylene copolymer comprising ethylene in an amount of less than about 18 wt% based on the total weight of the propylene / ethylene copolymer, a second polymer phase comprising wherein the ratio of the melt flow rate of the polypropylene homopolymer or random copolymer to the melt flow rate of the propylene / ethylene copolymer is greater than about 1.0, The first polymer phase and the second polymer phase combine to provide the polypropylene composition having a melt flow rate of about 4 g / 10 min or less, an ethylene content of less than about 5 wt%, a total low temperature xylene soluble content of about 5 wt% to about 20 wt%, a haze at 1 mm of less than about 20%, an Izod impact strength at 23°C exceeding about 500 J / m, a Gardner falling weight impact strength at 0°C exceeding about 17 Nm (150 inch - pounds), and a flexural modulus of about 800 MPa or more. A polypropylene composition is provided.

[0041]

[0044] In any embodiment, the first polymer phase includes a crystalline matrix including a polypropylene homopolymer or random copolymer. In any embodiment, the polypropylene composition includes a heterophasic propylene copolymer. In some embodiments, butene may also be present in the second polymer phase. In some embodiments, the propylene / ethylene copolymer present in the second polymer phase includes butene.

[0042]

[0045] The first polymer phase including a polypropylene homopolymer or random copolymer may optionally include one or more comonomers in an amount of about 3 wt% or less based on the total weight of the propylene homopolymer or copolymer. In some embodiments, the first polymer phase includes a polypropylene homopolymer or random copolymer and includes one or more comonomers in an amount of about 0 wt% to about 3 wt%, including about 0 wt%, about 0.5 wt%, about 1.0 wt%, about 1.5 wt%, about 2.0 wt%, about 2.5 wt%, and about 3.0 wt% based on the total weight of the propylene homopolymer or copolymer.

[0043]

[0046] The first polymer phase comprising a polypropylene homopolymer or random copolymer may have a total low temperature xylene soluble content of from about 2% to about 6% by weight, including about 2.1% by weight, about 2.2% by weight, about 2.3% by weight, about 2.4% by weight, about 2.5% by weight, about 2.6% by weight, about 2.7% by weight, about 2.8% by weight, about 2.9% by weight, about 3.0% by weight, about 3.1% by weight, about 3.2% by weight, about 3.3% by weight, about 3.4% by weight, about 3.5% by weight, about 3.6% by weight, about 3.7% by weight, about 3.8% by weight, about 3.9% by weight, about 4.0% by weight, 4.1% by weight, about 4.2% by weight, about 4.3% by weight, about 4.4% by weight, about 4.5% by weight, about 4.6% by weight, about 4.7% by weight, about 4.8% by weight, about 4.9% by weight, about 5.0% by weight, 5.1% by weight, about 5.2% by weight, about 5.3% by weight, about 5.4% by weight, about 5.5% by weight, about 5.6% by weight, about 5.7% by weight, about 5.8% by weight, about 5.9% by weight, and about 6.0% by weight. In some embodiments, the first polymer phase comprises a polypropylene homopolymer or random copolymer and has a total low temperature xylene soluble content of about 2.5% by weight or about 4.8% by weight.

[0044]

[0047] The first polymer phase comprising a polypropylene homopolymer or random copolymer may have a melt flow rate of from about 0.5 g / 10 min to about 3 g / 10 min, including about 0.5 g / 10 min, about 0.6 g / 10 min, about 0.7 g / 10 min, about 0.8 g / 10 min, about 0.9 g / 10 min, about 1.0 g / 10 min, about 1.1 g / 10 min, about 1.2 g / 10 min, about 1.3 g / 10 min, about 1.4 g / 10 min, about 1.5 g / 10 min, about 1.6 g / 10 min, about 1.7 g / 10 min, about 1.8 g / 10 min, about 1.9 g / 10 min, about 2.0 g / 10 min, about 2.1 g / 10 min, about 2.2 g / 10 min, about 2.3 g / 10 min, about 2.4 g / 10 min, about 2.5 g / 10 min, about 2.6 g / 10 min, about 2.7 g / 10 min, about 2.8 g / 10 min, about 2.9 g / 10 min, and about 3.0 g / 10 min. In some embodiments, the first polymer phase comprises a polypropylene homopolymer or random copolymer and has a melt flow rate of from about 0.5 g / 10 min to about 1.5 g / 10 min. In some embodiments, the first polymer phase comprises a polypropylene homopolymer or random copolymer and has a melt flow rate of about 0.9 g / 10 min.

[0045]

[0048] The polypropylene composition may have a melt flow rate of 4 g / 10 min or less, including about 0.5 g / 10 min, about 1 g / 10 min, about 1.5 g / 10 min, about 2 g / 10 min, about 2.5 g / 10 min, about 3 g / 10 min, about 3.5 g / 10 min, and about 4 g / 10 min. In some embodiments, the polypropylene composition has a melt flow rate of from about 0.5 g / 10 min to about 1.5 g / 10 min.

[0046]

[0049] The polypropylene composition may have an ethylene content of less than 5 wt%, including about 0.5 wt%, about 1 wt%, about 1.5 wt%, about 2 wt%, about 2.5 wt%, about 3 wt%, about 3.5 wt%, about 4 wt%, about 4.5 wt%, and about 5 wt%. In some embodiments, the polypropylene composition has an ethylene content of from about 2 wt% to about 4.5 wt%.

[0047]

[0050] The polypropylene composition may have a total low-temperature xylene-soluble content of about 5 wt% to about 20 wt%, including about 5 wt%, about 6 wt%, about 7 wt%, about 8 wt%, about 9 wt%, about 10 wt%, about 11 wt%, about 12 wt%, about 13 wt%, about 14 wt%, about 15 wt%, about 16 wt%, about 17 wt%, about 18 wt%, about 19 wt%, and about 20 wt%. In some embodiments, the polypropylene composition has a total low-temperature xylene-soluble content of about 7 wt% or about 12 wt%.

[0048]

[0051] The polypropylene composition may have a haze at 1 mm of less than about 20%, including about 1%, about 2%, about 3%, about 4%, about 5%, about 6%, about 7%, about 8%, about 9%, about 10%, about 11%, about 12%, about 13%, about 14%, about 15%, about 16%, about 17%, about 18%, about 19%, and about 20%. In some embodiments, the polypropylene composition has a haze at 1 mm of about 5% to about 15%.

[0049]

[0052] The polypropylene composition may have an Izod impact strength at 23°C of greater than about 500 J / m, including about 500 J / m, about 525 J / m, about 575 J / m, about 600 J / m, about 625 J / m, about 650 J / m, about 675 J / m, about 700 J / m, about 725 J / m, about 750 J / m, about 775 J / m, about 800 J / m, about 825 J / m, about 850 J / m, about 875 J / m, and about 900 J / m. In some embodiments, the polypropylene composition has an Izod impact strength at 23°C of about 500 J / m to about 900 J / m.

[0050]

[0053] The polypropylene composition may have a Gardner falling impact strength at 0 °C exceeding about 17 Nm (150 inch-pounds), including about 17 Nm (150 inch-pounds), about 19.8 Nm (175 inch-pounds), about 22.6 Nm (200 inch-pounds), about 25.4 Nm (225 inch-pounds), about 28.3 Nm (250 inch-pounds), about 31.1 Nm (275 inch-pounds), about 33.9 Nm (300 inch-pounds), about 36.7 Nm (325 inch-pounds), and about 39.6 Nm (350 inch-pounds). In some embodiments, the polypropylene composition has a Gardner falling impact strength at 0 °C of from about 17 Nm (150 inch-pounds) to about 39.6 Nm (350 inch-pounds).

[0051]

[0054] The polypropylene composition may have a flexural modulus of about 800 MPa or more, including about 800 MPa, about 825 MPa, about 850 MPa, about 870 MPa, about 900 MPa, about 925 MPa, about 950 MPa, about 975 MPa, about 1000 MPa, about 1025 MPa, about 1050 MPa, about 1075 MPa, about 1100 MPa, about 1125 MPa, about 1150 MPa, about 1175 MPa, about 1200 MPa, about 1225 MPa, about 1250 MPa, about 1275 MPa, and about 1300 MPa. In some embodiments, the polypropylene composition has a flexural modulus of from about 800 MPa to about 1300 MPa.

[0052]

[0055] The polypropylene composition described herein may have high transparency, high toughness, and high rigidity. In another aspect, a polypropylene composition comprising (a) a first polymer phase comprising a polypropylene homopolymer or random copolymer, wherein the polypropylene homopolymer or random copolymer optionally contains one or more comonomers in an amount of about 1 wt% or less based on the total weight of the propylene homopolymer or copolymer, has a total low temperature xylene soluble content of less than about 4 wt%, and has a melt flow rate of from about 2 g / 10 min to about 5 g / 10 min; a first polymer phase, (b) A second polymer phase comprising a propylene / ethylene copolymer, wherein the propylene / ethylene copolymer comprises less than about 18% by weight of ethylene, based on the total weight of the propylene / ethylene copolymer, and a second polymer phase comprising; The ratio of the melt flow rate of the polypropylene homopolymer or random copolymer to the melt flow rate of the propylene / ethylene copolymer is greater than about 1.0, The first polymer phase and the second polymer phase together have a melt flow rate of about 5 g / 10 min or less, an ethylene content of less than about 3.5% by weight, a total low-temperature xylene-soluble content of about 5% to about 15% by weight, a haze at 1 mm of less than about 20%, an Izod impact strength at 23 °C of greater than about 200 J / m, and a flexural modulus of about 1100 MPa or more, to provide the polypropylene composition. A polypropylene composition is provided.

[0053]

[0056] The first polymer phase comprising a polypropylene homopolymer or random copolymer may optionally comprise one or more comonomers in an amount of about 1% by weight or less, based on the total weight of the polypropylene homopolymer or copolymer, including about 0.1% by weight, about 0.2% by weight, about 0.3% by weight, about 0.4% by weight, about 0.5% by weight, about 0.6% by weight, about 0.7% by weight, about 0.8% by weight, about 0.9% by weight, and about 1% by weight. In some embodiments, the first polymer phase comprises a polypropylene homopolymer or a random copolymer comprising one or more comonomers in an amount of about 0.5% to about 1% by weight, based on the total weight of the polypropylene homopolymer or copolymer.

[0054]

[0057] The first polymer phase comprising a polypropylene homopolymer or random copolymer may have a total low temperature xylene soluble content of less than about 4 wt%, including about 0.5 wt%, about 1 wt%, about 1.5 wt%, about 2 wt%, about 2.5 wt%, about 3 wt%, about 3.5 wt%, and about 4 wt%. In some embodiments, the first polymer phase comprises a polypropylene homopolymer or random copolymer and has a total low temperature xylene soluble content of about 1 wt% to about 3 wt%.

[0055]

[0058] The first polymer phase comprising a polypropylene homopolymer or random copolymer may have a melt flow rate of about 2 g / 10 min to about 5 g / 10 min, including about 2 g / 10 min, about 2.5 g / 10 min, about 3 g / 10 min, about 3.5 g / 10 min, about 4 g / 10 min, about 4.5 g / 10 min, and about 5 g / 10 min. In some embodiments, the first polymer phase comprises a polypropylene homopolymer or random copolymer and has a melt flow rate of about 2 g / 10 min to about 4 g / 10 min.

[0056]

[0059] The polypropylene composition may have a melt flow rate of about 5 g / 10 min or less, including about 0.5 g / 10 min, about 1 g / 10 min, about 1.5 g / 10 min, about 2 g / 10 min, about 2.5 g / 10 min, about 3 g / 10 min, about 3.5 g / 10 min, about 4 g / 10 min, about 4.5 g / 10 min, and about 5 g / 10 min. In some embodiments, the polypropylene composition has a melt flow rate of about 2 g / 10 min to about 4 g / 10 min.

[0057]

[0060] The polypropylene composition may have an ethylene content of less than about 3.5 wt%, including about 0.5 wt%, about 1 wt%, about 1.5 wt%, about 2 wt%, about 2.5 wt%, about 3 wt%, and about 3.5 wt%. In some embodiments, the polypropylene composition has an ethylene content of about 2 wt% to about 3.5 wt%.

[0058]

[0061] The polypropylene composition may have a total low-temperature xylene soluble content of about 5 wt% to about 15 wt%, including about 5 wt%, about 5.5 wt%, about 6 wt%, about 6.5 wt%, about 7 wt%, about 7.5 wt%, about 8 wt%, about 8.5 wt%, about 9 wt%, about 9.5 wt%, about 10 wt%, about 10.5 wt%, about 11 wt%, about 11.5 wt%, about 12 wt%, about 12.5 wt%, about 13 wt%, about 13.5 wt%, about 14 wt%, about 14.5 wt%, and about 15 wt%. In some embodiments, the polypropylene composition has a total low-temperature xylene soluble content of about 5.5 wt% or about 12 wt%.

[0059]

[0062] The polypropylene composition may have a haze at 1 mm of less than about 20%, including about 1%, about 2%, about 3%, about 4%, about 5%, about 6%, about 7%, about 8%, about 9%, about 10%, about 11%, about 12%, about 13%, about 14%, about 15%, about 16%, about 17%, about 18%, about 19%, and about 20%. In some embodiments, the polypropylene composition has a haze at 1 mm of about 10% to about 20%.

[0060]

[0063] The polypropylene composition may have an Izod impact strength at 23°C of greater than about 200 J / m, including about 200 J / m, about 225 J / m, about 250 J / m, about 275 J / m, about 300 J / m, about 325 J / m, about 375 J / m, about 400 J / m, about 425 J / m, about 450 J / m, about 475 J / m, about 500 J / m, about 525 J / m, about 550 J / m, about 575 J / m, about 600 J / m, about 625 J / m, about 650 J / m, about 675 J / m, about 700 J / m, about 725 J / m, about 750 J / m, about 775 J / m, about 800 J / m, about 825 J / m, about 850 J / m, about 875 J / m, and about 900 J / m. In some embodiments, the polypropylene composition has an Izod impact strength at 23°C of about 200 J / m to about 900 J / m. In some embodiments, the polypropylene composition has an Izod impact strength at 23°C of about 200 J / m to about 600 J / m.

[0061]

[0064] The polypropylene composition may have a flexural modulus of at least about 1200 MPa, including about 1200 MPa, about 1225 MPa, about 1250 MPa, about 1275 MPa, about 1300 MPa, about 1325 MPa, about 1350 MPa, about 1375 MPa, about 1400 MPa, about 1425 MPa, about 1450 MPa, about 1475 MPa, about 1500 MPa, about 1525 MPa, about 1550 MPa, about 1575 MPa, and about 1600 MPa. In some embodiments, the polypropylene composition has a flexural modulus of about 1200 MPa to about 1500 MPa. In some embodiments, the polypropylene composition has a flexural modulus of about 1200 MPa to about 1600 MPa.

[0062]

[0065] The second polymer phase may include a propylene / ethylene copolymer containing ethylene in an amount of less than about 18 wt%, including about 1 wt%, about 2 wt%, about 3 wt%, about 4 wt%, about 5 wt%, about 6 wt%, about 7 wt%, about 8 wt%, about 9 wt%, about 10 wt%, about 11 wt%, about 12 wt%, about 13 wt%, about 14 wt%, about 15 wt%, about 16 wt%, about 17 wt%, and about 18 wt%, based on the total weight of the propylene / ethylene copolymer. In any embodiment, the second polymer phase includes a propylene / ethylene copolymer containing ethylene in an amount of about 10 wt% to about 18 wt% based on the total weight of the propylene / ethylene copolymer.

[0063]

[0066] The ratio of the melt flow rate of the polypropylene homopolymer or random copolymer to the melt flow rate of the propylene / ethylene copolymer includes about 1.0, about 1.5, about 2.0, about 2.5, and about 3.0 and may be greater than about 1.0. In any embodiment, the ratio of the melt flow rate of the polypropylene homopolymer or random copolymer to the melt flow rate of the propylene / ethylene copolymer is about 1.0 to about 3.0.

[0064]

[0067] In any embodiment, the polypropylene composition has a Gardner impact strength at 23 °C greater than about 17 Nm (150 inch-pounds) and includes about 17 Nm (150 inch-pounds), about 19.8 Nm (175 inch-pounds), about 22.6 Nm (200 inch-pounds), about 25.4 Nm (225 inch-pounds), about 28.3 Nm (250 inch-pounds), about 31.1 Nm (275 inch-pounds), about 33.9 Nm (300 inch-pounds), about 36.7 Nm (325 inch-pounds), and about 39.6 Nm (350 inch-pounds).

[0065]

[0068] In any embodiment, the one or more comonomers present in the polypropylene homopolymer or random copolymer are ethylene, butene, 1-hexene, and 1-octene. In some embodiments, the one or more comonomers present in the polypropylene homopolymer or random copolymer is ethylene.

[0066]

[0069] The polypropylene compositions of the present disclosure may contain various other additives and ingredients. For example, the polypropylene composition can contain a nucleating agent, a release agent, a lubricant, an antiblocking agent, a UV stabilizer, a heat stabilizer, a pigment / tinting agent, and the like. In one embodiment, the polymer composition can contain an antioxidant such as a hindered phenolic antioxidant. The polymer composition can also contain an acid neutralizer. For example, the polymer composition can contain an acid neutralizer and an antioxidant. The polymer composition can also contain an acid scavenger. Each of the additives can generally be present in the polymer composition in an amount less than about 3 wt%, such as less than about 2 wt%, such as less than about 1 wt%, such as less than about 0.5 wt%, generally in an amount greater than about 0.001 wt%. In any embodiment, the polypropylene composition further comprises one or more of a nucleating agent, an acid neutralizer, and an antioxidant.

[0067]

[0070] In one embodiment, the polypropylene composition can further contain a nucleating agent. The nucleating agent can be added to further improve the permeability characteristics of the composition. The nucleating agent can include, for example, a compound capable of generating a gelled network within the composition.

[0068]

[0071] In one embodiment, the nucleating agent may include a sorbitol compound, such as a sorbitol acetal derivative. In one embodiment, for example, the nucleating agent may include dibenzyl sorbitol.

[0069]

[0072] Regarding sorbitol acetal derivatives that can be used as additives in some embodiments, the sorbitol acetal derivative has the formula (I):

[0070]

Chemical formula

[0071] [wherein, R1 - R5 include the same or different moieties selected from hydrogen and C1 - C3 alkyl] and is represented by.

[0072]

[0073] In some embodiments, R1-R5 are hydrogen, and as a result, the sorbitol acetal derivative is 2,4-dibenzylidene sorbitol ("DBS"). In some embodiments, R1, R4, and R5 are hydrogen, and R2 and R3 are methyl groups, and as a result, the sorbitol acetal derivative is 1,3:2,4-di-p-methyldibenzylidene-D-sorbitol ("MDBS"). In some embodiments, R1-R4 are methyl groups and R5 is hydrogen, and as a result, the sorbitol acetal derivative is 1,3:2,4-bis(3,4-dimethylbenzylideno)sorbitol ("DMDBS"). In some embodiments, R2, R3, and R5 are propyl groups (-CH2-CH2-CH3) and R1 and R4 are hydrogen, and as a result, the sorbitol acetal derivative is 1,2,3-trideoxy-4,6:5,7-bis-O-(4-propylphenylmethylene)nonitol ("TBPMN").

[0073]

[0074] Other embodiments of nucleating agents that may be used include 1,3:2,4-dibenzylidene sorbitol, 1,3:2,4-bis(p-methylbenzylidene)sorbitol, di(p-methylbenzylidene)sorbitol, di(p-ethylbenzylidene)sorbitol, bis(5’,6’,7’,8’-tetrahydro-2-naphthyldene)sorbitol.

[0074]

[0075] In one embodiment, the nucleating agent may also include bisamides such as benzene trisamide. The above nucleating agents can be used alone or in combination.

[0076] When present in the polymer composition, one or more nucleating agents are generally added in an amount exceeding about 200 ppm, for example in an amount exceeding about 1,800 ppm, for example in an amount exceeding about 2,000 ppm, for example in an amount exceeding about 2,200 ppm. One or more nucleating agents are generally present in an amount less than about 8,000 ppm, for example less than about 6,000 ppm, for example less than about 5,000 ppm. The amount of nucleating agent present in the composition can depend on various factors including the type of nucleating agent used. In some embodiments, one or more nucleating agents are present in an amount of about 5000 ppm or less.

[0075]

[0077] The polymer of the first phase and the polymer of the second phase may be produced using various different polymerization methods and procedures. In one embodiment, a Ziegler-Natta catalyst is used to produce both polymers. For example, the polymerization of an olefin may be carried out in the presence of a catalyst system comprising a catalyst, an internal electron donor, a cocatalyst, and optionally an external electron donor. An olefin of the formula CH 2 =CHR [wherein R is hydrogen or a hydrocarbon radical having from 1 to 12 atoms] may be contacted with the catalyst system under suitable conditions to form a polymer product. The copolymerization may be carried out in a method step process to generate the heterogeneous composition of the present disclosure. The polymerization process may be carried out using known techniques using a fluidized bed or stirred bed reactor in the gas phase, or using an inert hydrocarbon solvent or diluent or liquid monomer in the slurry phase.

[0076]

[0078] In one embodiment, the polymer of the first phase and the polymer of the second phase may be produced by a two-step method including a first step in which a propylene random copolymer of a continuous polymer phase is prepared and a second step in which an ethylene-propylene copolymer is produced. The polymerization in the first step may be carried out in one or more bulk reactors or one or more gas-phase reactors. The polymerization in the second step may be carried out in one or more gas-phase reactors. The polymerization in the second step is typically carried out immediately following the polymerization in the first step. For example, the polymerization product recovered from the first polymerization step can be sent immediately to the second polymerization step. A heterophasic copolymer composition is produced.

[0077]

[0079] In yet another aspect, a method for preparing any one of the polypropylene compositions described herein by sequential polymerization in the presence of a Ziegler-Natta catalyst, preparing a first polymer phase in a first gas-phase reactor; transferring the first polymer phase to a second gas-phase reactor containing a second polymer phase; comprising providing a polypropylene composition by combining the first polymer phase with the second polymer phase. A method is provided.

[0078]

[0080] In yet another aspect, a method for preparing any one of the polypropylene compositions described herein, supplying propylene and optionally one or more comonomers to a first reactor, and supplying to the first reactor a catalyst mixture comprising (1) a Ziegler-Natta catalyst, (2) a cocatalyst, and (3) an external donor; contacting propylene with the catalyst mixture under first polymerization conditions to polymerize propylene and optionally one or more comonomers to form a first polymer phase comprising a propylene homopolymer or copolymer; transferring at least a portion of the first polymer phase to a second reactor; Supplying additional propylene and ethylene to a second reactor to form a second polymer phase comprising There is provided a method that results in a polypropylene composition by combining a first polymer phase with a second polymer phase. In some embodiments, the second polymer phase may further comprise butene. In some embodiments, the step of supplying additional propylene and ethylene to the second reaction also comprises the step of supplying butene to form the second polymer phase.

[0079]

[0081] In one embodiment of the present disclosure, the polymerization is carried out in the presence of a stereospecific olefin polymerization catalyst.

[0082] In one embodiment, the catalyst comprises a procatalyst composition containing a titanium moiety such as titanium chloride, a magnesium moiety such as magnesium chloride, and at least one internal electron donor.

[0080]

[0083] The procatalyst precursor may comprise (i) magnesium, (ii) a transition metal compound from Groups IV-VII of the periodic table, (iii) a halide, an oxylahilde, and / or an alkoxide, and / or an alkoxide of (i) or (i) and / or (ii), and (iv) a combination of (i), (ii) and (iii). Non-limiting examples of suitable procatalyst precursors include halides, oxylahalides, alkoxides, and combinations thereof of magnesium, manganese, titanium, vanadium, chromium, molybdenum, zirconium, hafnium.

[0081]

[0084] In embodiments, the procatalyst precursor contains magnesium as the only metal component. Non-limiting examples include anhydrous magnesium chloride and / or its alcohol adducts, magnesium alkoxides, and / or aryloxides, mixed magnesium alkoxyhalides, and / or carboxylated magnesium dialkoxides or aryloxides.

[0082]

[0085] In an embodiment, the procatalyst precursor is an alcohol adduct of magnesium chloride anhydride. The magnesium chloride anhydride adduct is generally defined as MgCl 2 -nROH [wherein n has an alcohol in the range of 1.5 to 6.0, preferably 2.5 to 4.0, and most preferably 2.8 to 3.5 moles in total]. ROH is a linear or branched alcohol of C 1 -C 4 , or a mixture of alcohols. Preferably, ROH is ethanol or a mixture of ethanol and a higher alcohol. When ROH is a mixture, the molar ratio of ethanol to the higher alcohol is at least 80:20, preferably 90:10, and most preferably at least 95:5.

[0083]

[0086] In one embodiment, the substantially spherical MgCl 2 -nEtOH adduct may be formed by a spray crystallization process. In one embodiment, the spherical MgCl 2 precursor has an average particle size (Malvern d 50 ) between about 15 and 150 microns, preferably between 20 and 100 microns, and most preferably between 35 and 85 microns.

[0084]

[0087] In one embodiment, the procatalyst precursor contains a transition metal compound and a magnesium metal compound. The transition metal compound has the general formula TrX x [wherein Tr is a transition metal, X is a halogen or a C 1-10 hydrocarboxyl or hydrocarbyl group, and x is the number of such X groups in the compound in combination with the magnesium metal compound]. Tr may be a Group IV, V, or VI metal. In one embodiment, Tr is a Group IV metal such as titanium. X may be chloride, bromide, a C 1-4 alkoxide or phenoxide, or a mixture thereof. In one embodiment, X is chloride.

[0085]

[0088] The precursor composition may be prepared by chlorination of the aforementioned magnesium compound, titanium compound, or a mixture thereof.

[0089] In one embodiment, the precursor composition has the formula Mg d Ti(OR e ) f X g [wherein, R e is an aliphatic or aromatic hydrocarbon radical having 1 to 14 carbon atoms or COR’, where R’ is an aliphatic group or an aromatic hydrocarbon radical having 1 to 14 carbon atoms; each OR e group is the same or different; X is independently chlorine, bromine, or iodine; d is 0.5 to 56; or 2 to 4, or 3; f is 2 to 116, or 5 to 15; and g is 0.5 to 116, or 1 to 3] and is a mixed magnesium / titanium compound.

[0086]

[0090] According to the present disclosure, the above-mentioned procatalyst precursor is combined with at least one internal electron donor. The internal electron donor may include a substituted phenylene aromatic diester.

[0091] In one embodiment, the first internal electron donor has the following structure (I):

[0087]

Chemical formula

[0088] [wherein, R 1 -R 14 are the same or different] and includes a substituted phenylene aromatic diester having. Each of R 1 -R 14 is selected from hydrogen, a substituted hydrocarbyl group having 1 to 20 carbon atoms, an unsubstituted hydrocarbyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a heteroatom, and combinations thereof. At least one of R 1 -R 14 is not hydrogen.

[0089]

[0092] In one embodiment, the substituted phenylene aromatic diester may be any substituted phenylene aromatic diester disclosed in U.S. Patent Application No. 61 / 141,959, filed on December 31, 2008, the entire content of which is incorporated herein by reference.

[0090]

[0093] In one embodiment, the substituted phenylene aromatic diester may also be any substituted phenylene aromatic diester disclosed in International Publication No. WO 2012 / 088028, filed on December 20, 2011, the entire content of which is incorporated herein by reference.

[0091]

[0094] In one embodiment, at least one (or two, or three, or four) of the R groups (plural available) of R 1 -R 4 is selected from a substituted hydrocarbyl group having 1 to 20 carbon atoms, an unsubstituted hydrocarbyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a heteroatom, and combinations thereof.

[0092]

[0095] In one embodiment, at least one (or some, or all) of the R groups (plural available) of R 5 -R 14 is selected from a substituted hydrocarbyl group having 1 to 20 carbon atoms, an unsubstituted hydrocarbyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a heteroatom, and combinations thereof. In another embodiment, at least one of the R groups of R 5 -R 9 and at least one of the R groups of R 10 -R 14 is selected from a substituted hydrocarbyl group having 1 to 20 carbon atoms, an unsubstituted hydrocarbyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a heteroatom, and combinations thereof.

[0093]

[0096] In one embodiment, at least one of the R groups of R 1 -R 4 and at least one of the R groups of R 5 -R14 At least one of them is selected from a substituted hydrocarbyl group having 1 to 20 carbon atoms, an unsubstituted hydrocarbyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a heteroatom, and combinations thereof. In another embodiment, R 1 -R 4 At least one of, R 5 -R 9 At least one of and R 10 -R 14 At least one of is selected from a substituted hydrocarbyl group having 1 to 20 carbon atoms, an unsubstituted hydrocarbyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a heteroatom and combinations thereof.

[0094]

[0097] In one embodiment, any consecutive series of R groups of R 1 -R 4 , and / or any consecutive series of R groups of R 5 -R 9 , and / or any consecutive series of R groups of R 10 -R 14 may be linked to form an intercyclic or endocyclic structure. The inter / endocyclic structure may be aromatic or non-aromatic. In one embodiment, the inter / endocyclic structure is a C 5 or C 6 -membered ring.

[0095]

[0098] In one embodiment, at least one of R 1 -R 4 is selected from a substituted hydrocarbyl group having 1 to 20 carbon atoms, an unsubstituted hydrocarbyl group having 1 to 20 carbon atoms, and combinations thereof. Optionally, at least one of R 5 -R 14 may be a halogen atom or an alkoxy group having 1 to 20 carbon atoms. Optionally, R 1 -R 4 , and / or R 5 -R 9 , and / or R 10 -R 14They may be linked to form an intercyclic structure or an intracyclic structure. The intercyclic structure and / or intracyclic structure may or may not be aromatic.

[0096]

[0099] In one embodiment, R 1 -R 4 , and / or R 5 -R 9 , and / or R 10 -R 14 Any consecutive series of R groups may be members of a C 5 -C 6 member ring.

[0100] In one embodiment, Structure (I) contains hydrogen as R 1 , R 3 and R 4 . R 2 is selected from substituted hydrocarbyl groups having 1 to 20 carbon atoms, unsubstituted hydrocarbyl groups having 1 to 20 carbon atoms, and combinations thereof. R 5 -R 14 may be the same or different, and each of R 5 -R 14 is selected from hydrogen, substituted hydrocarbyl groups having 1 to 20 carbon atoms, unsubstituted hydrocarbyl groups having 1 to 20 carbon atoms, alkoxy groups having 1 to 20 carbon atoms, halogen, and combinations thereof.

[0097]

[0101] In one embodiment, R 2 is selected from C 1 -C 8 alkyl groups, C 3 -C 6 cycloalkyls, or substituted C 3 -C 6 cycloalkyl groups. R 2 may be a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a t-butyl group, an isobutyl group, a sec-butyl group, a 2,4,4-trimethylpentan-2-yl group, a cyclopentyl group, and a cyclohexyl group.

[0098]

[0102] In one embodiment, R in Structure (I) is methyl 2 and each of R 5 -R 14 is hydrogen.

[0103] In one embodiment, R in Structure (I) is ethyl 2 and each of R 5 -R 14 is hydrogen.

[0099]

[0104] In one embodiment, R in Structure (I) is t-butyl 2 and each of R 5 -R 14 is hydrogen.

[0105] In one embodiment, R in Structure (I) is ethoxycarbonyl 2 and each of R 5 -R 14 is hydrogen.

[0100]

[0106] In one embodiment, R in Structure (I) is hydrogen for R 2 , R 3 and R 4 each, and R 1 is selected from substituted hydrocarbyl groups having 1 to 20 carbon atoms, unsubstituted hydrocarbyl groups having 1 to 20 carbon atoms, and combinations thereof. R 5 -R 14 are the same or different and each is selected from hydrogen, substituted hydrocarbyl groups having 1 to 20 carbon atoms, unsubstituted hydrocarbyl groups having 1 to 20 carbon atoms, alkoxy groups having 1 to 20 carbon atoms, halogen, and combinations thereof.

[0101]

[0107] In one embodiment, R in Structure (I) is methyl 1 and each of R 5 -R 14 is hydrogen.

[0108] In one embodiment, R in Structure (I) is hydrogen for R 2 and R 4 each, and R 1 and R 3are the same or different. R 1 and R 3 each is selected from a substituted hydrocarbyl group having 1 to 20 carbon atoms, an unsubstituted hydrocarbyl group having 1 to 20 carbon atoms, and combinations thereof. R 5 -R 14 are the same or different, and each of R 5 -R 14 is selected from a substituted hydrocarbyl group having 1 to 20 carbon atoms, an unsubstituted hydrocarbyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a halogen, and combinations thereof.

[0102]

[0109] In one embodiment, Structure (I) includes the same or different R 1 and R 3 . Each of R 1 and R 3 is selected from a C 1 -C 8 alkyl group, a C 3 -C 6 cycloalkyl group, or a substituted C 3 -C 6 cycloalkyl group. Each of R 5 -R 14 is the same or different, and each of R 5 -R 14 is selected from hydrogen, a C 1 -C 8 alkyl group, and a halogen. Non-limiting examples of suitable C 1 -C 8 alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, i-butyl, t-butyl, n-pentyl, i-pentyl, neopentyl, t-pentyl, n-hexyl, and 2,4,4-trimethylpentan-2-yl groups. Non-limiting examples of suitable C 3 -C 6 cycloalkyl groups include cyclopentyl and cyclohexyl groups. In a further embodiment, at least one of R 5 -R 14 is a C 1 -C 8 alkyl group or a halogen.

[0103]

[0110] In one embodiment, R of structure (I) is a methyl group 1 , and R of structure (I) is a t-butyl group 3 . Each of R 2 , R 4 and R 5 -R 14 is hydrogen.

[0111] In one embodiment, structure (I) contains R 1 and R 3 which are isopropyl groups. Each of R 2 , R 4 and R 5 -R 14 is hydrogen.

[0104]

[0112] In one embodiment, structure (I) contains R 1 , R 5 and R 10 as methyl groups respectively, and R 3 is a t-butyl group. Each of R 2 , R 4 , R 6 -R 9 and R 11 -R 14 is hydrogen.

[0105]

[0113] In one embodiment, structure (I) contains R 1 , R 7 , and R 12 as methyl groups respectively, and R 3 is a t-butyl group. Each of R 2 , R 4 , R 5 , R 6 , R 8 , R 9 , R 10 , R 11 , R 13 , and R 14 is hydrogen.

[0106]

[0114] In one embodiment, structure (I) contains R 1 as a methyl group, and R 3 is a t-butyl group. R 7and R 12 Each of them is an ethyl group. R 2 R 4 R 5 R 6 R 8 R 9 R 10 R 11 R 13 and R 14 Each of them is hydrogen.

[0107]

[0115] In one embodiment, structure (I) contains R as a methyl group 1 R 5 R 7 R 9 R 10 R 12 and R 14 respectively, and R 3 is a t-butyl group. R 2 R 4 R 6 R 8 R 11 and R 13 Each of them is hydrogen.

[0108]

[0116] In one embodiment, structure (I) contains R as a methyl group 1 R 3 is a t-butyl group. R 5 R 7 R 9 R 10 R 12 and R 14 Each of them is an i-propyl group. R 2 R 4 R 6 R 8 R 11 and R 13 Each of them is hydrogen.

[0109]

[0117] In one embodiment, the substituted phenylene aromatic diester has structure (II) containing R as a methyl group 1 R 3 is a t-butyl group. R 2 and R 4 Each of them is hydrogen. R8 and R 9 is a member of the C 6 member ring that forms a 1-naphthoyl moiety. R 13 and R 14 is a member of the C 6 member ring that forms another 1-naphthoyl moiety. Structure (II) is given below.

[0110]

Chem.

[0111]

[0118] In one embodiment, the substituted phenylene aromatic diester has a structure (III) containing R 1 which is a methyl group, and R 3 is a t-butyl group. Each of R 2 and R 4 is hydrogen. R 6 and R 7 are members of the C 6 member ring that forms a 2-naphthoyl moiety. R 12 and R 13 are members of the C 6 member ring that forms a 2-naphthoyl moiety. Structure (III) is given below.

[0112]

Chem.

[0113]

[0119] In one embodiment, structure (I) contains R 1 which is a methyl group, and R 3 is a t-butyl group. Each of R 7 and R 12 is an ethoxy group. Each of R 2 , R 4 , R 5 , R 6 , R 8 , R 9 , R 10 , R 11 , R 13 , and R 14 is hydrogen.

[0114]

[0120] In one embodiment, R in structure (I) is a methyl group 1 and contains R 3 which is a t-butyl group. Each of R 7 and R 12 is a fluorine atom. Each of R 2 , R 4 , R 5 , R 6 , R 8 , R 9 , R 10 , R 11 , R 13 , and R 14 is hydrogen.

[0115]

[0121] In one embodiment, R in structure (I) is a methyl group 1 and contains R 3 which is a t-butyl group. Each of R 7 and R 12 is a chlorine atom. Each of R 2 , R 4 , R 5 , R 6 , R 8 , R 9 , R 10 , R 11 , R 13 , and R 14 is hydrogen.

[0116]

[0122] In one embodiment, R in structure (I) is a methyl group 1 and contains R 3 which is a t-butyl group. Each of R 7 and R 12 is a bromine atom. Each of R 2 , R 4 , R 5 , R 6 , R 8 , R 9 , R 10 , R 11 , R 13 , and R 14 is hydrogen.

[0117]

[0123] In one embodiment, R in structure (I) is a methyl group1 comprising R 3 is a t-butyl group. R 7 and R 12 each is an iodine atom. R 2 、R 4 、R 5 、R 6 、R 8 、R 9 、R 10 、R 11 、R 13 、and R 14 each is hydrogen.

[0118]

[0124] In one embodiment, structure (I) comprises R which is a methyl group 1 comprising R 3 is a t-butyl group. R 6 、R 7 、R 11 、and R 12 each is a chlorine atom. R 2 、R 4 、R 5 、R 8 、R 9 、R 10 、R 13 、and R 14 each is hydrogen.

[0119]

[0125] In one embodiment, structure (I) comprises R which is a methyl group 1 comprising R 3 is a t-butyl group. R 6 、R 8 、R 11 、and R 13 each is a chlorine atom. R 2 、R 4 、R 5 、R 7 、R 9 、R 10 、R 12 、and R 14 each is hydrogen.

[0120]

[0126] In one embodiment, structure (I) comprises R which is a methyl group 1 comprising R 3 is a t-butyl group. R2 and R 4 and R 5 -R 14 Each of them is a fluorine atom.

[0127] In one embodiment, in structure (I), R 1 contains a methyl group, and R 3 is a t-butyl group. Each of R 7 and R 12 is a trifluoromethyl group. Each of R 2 , R 4 , R 5 , R 6 , R 8 , R 9 , R 10 , R 11 , R 13 , and R 14 is hydrogen.

[0121]

[0128] In one embodiment, in structure (I), R 1 contains a methyl group, and R 3 is a t-butyl group. Each of R 7 and R 12 is an ethoxycarbonyl group. Each of R 2 , R 4 , R 5 , R 6 , R 8 , R 9 , R 10 , R 11 , R 13 and R 14 is hydrogen.

[0122]

[0129] In one embodiment, R 1 is a methyl group, and R 3 is a t-butyl group. Each of R 7 and R 12 is an ethoxy group. Each of R 2 , R 4 , R 5 , R 6 , R 8 , R 9 , R 10 , R 11 , R 13 , and R 14Each of them is hydrogen.

[0123]

[0130] In one embodiment, structure (I) contains R which is a methyl group 1 and R 3 is a t-butyl group. Each of R 7 and R 12 is a diethylamino group. Each of R 2 , R 4 , R 5 , R 6 , R 8 , R 9 , R 10 , R 11 , R 13 , and R 14 is hydrogen.

[0124]

[0131] In one embodiment, structure (I) contains R which is a methyl group 1 and R 3 is a 2,4,4-trimethylpentan-2-yl group. Each of R 2 , R 4 and R 5 -R 14 is hydrogen.

[0125]

[0132] In one embodiment, structure (I) contains R 1 and R 3 each of which is a sec-butyl group. Each of R 2 , R 4 and R 5 -R 14 is hydrogen.

[0133] In one embodiment, the substituted phenylene aromatic diester has structure (IV), whereby R 1 and R 2 become members of a C 6 -membered ring to form a 1,2-naphthalene moiety. Each of R 5 -R 14 is hydrogen. Structure (IV) is given below.

[0126]

Chemical formula

[0127]

[0134] In one embodiment, the substituted phenylene aromatic diester has structure (V), whereby R 2 and R 3 are members of a C 6 member ring to form a 2,3-naphthalene moiety. Each of R 5 -R 14 is hydrogen. Structure (V) is given below.

[0128]

Chemical formula

[0129]

[0135] In one embodiment, structure (I) includes R 1 and R 4 , each of which is a methyl group. Each of R 2 , R 3 , R 5 -R 9 and R 10 -R 14 is hydrogen.

[0136] In one embodiment, structure (I) includes R 1 , which is a methyl group. R 4 is an i-propyl group. Each of R 2 , R 3 , R 5 -R 9 and R 10 -R 14 is hydrogen.

[0130]

[0137] In one embodiment, structure (I) includes R 1 , R 3 , and R 4 , each of which is an i-propyl group. Each of R 2 , R 5 -R 9 and R 10 -R 14 is hydrogen.

[0138] In one embodiment, R 1 and R 4Each of them is selected from a methyl group, an ethyl group, and a vinyl group. R 2 and R 3 each is selected from hydrogen, a secondary alkyl group or a tertiary alkyl group, and R 2 and R 3 are not hydrogen at the same time. Stated in another way, when R2 is hydrogen, R3 is not hydrogen (and vice versa).

[0131]

[0139] In one embodiment, a second internal electron donor containing a polyether that can generally coordinate in a bidentate manner may be used. In one embodiment, the second internal electron donor has the structure VI:

[0132]

Chemical formula

[0133] [wherein R 1 and R 2 are the same or different, methyl, C 2 -C 18 linear or branched alkyl, C 3 -C 18 cycloalkyl, C 4 -C 18 cycloalkylalkyl, C 4 -C 18 alkylcycloalkyl, phenyl, organosilicon, C 7 -C 18 arylalkyl, or C 7 -C 18 alkylaryl group and R 1 or R 2 may also be a hydrogen atom] is a substituted 1,3-diether of

[0134]

[0140] In one embodiment, the second internal electron donor has a cyclic or polycyclic structure VII:

[0135]

Chemical formula

[0136] [wherein, R 1 , R 2 , R 3 , and R 4 are as described for R 1 and R 2 of Structure VI, or together, one or more C 5 -C 7 may form a fused aromatic or non-aromatic ring structure, optionally containing an N, O or S heteroatom] may include a 1,3-diether having. Specific examples of the second internal electron donor include 4,4-bis(methoxymethyl)-2,6-dimethylheptane, 9,9-bis(methoxymethyl)fluorene, or mixtures thereof.

[0137]

[0141] The precursor is converted to a solid procatalyst by further reaction (halogenation) with an inorganic halide compound, preferably a titanium halide compound, and incorporation of an internal electron donor.

[0138]

[0142] One method suitable for halogenating the precursor is to react the precursor with a tetravalent titanium halide at a high temperature, optionally in the presence of a hydrocarbon or halocarbon diluent. A preferred tetravalent titanium halide is titanium tetrachloride.

[0139]

[0143] The resulting procatalyst composition can generally contain titanium in an amount of about 0.5% to about 6% by weight, such as about 1.5% to about 5% by weight, such as about 2% to about 4% by weight. The solid catalyst can generally contain magnesium in an amount exceeding about 5% by weight, such as exceeding about 8% by weight, such as exceeding about 10% by weight, such as exceeding about 12% by weight, such as exceeding about 14% by weight, such as exceeding about 16% by weight. Magnesium is contained in the catalyst in an amount less than about 25% by weight, such as less than about 23% by weight, such as less than about 20% by weight. The internal electron donor can be present in the catalyst composition in an amount less than about 30% by weight, such as less than about 25% by weight, such as less than about 22% by weight, such as less than about 20% by weight, such as less than about 19% by weight. The internal electron donor is generally present in an amount exceeding about 5% by weight, such as exceeding about 9% by weight.

[0140]

[0144] In one embodiment, the procatalyst composition is combined with a cocatalyst to form a catalyst system. The catalyst system is a system that forms an olefin-based polymer when contacted with an olefin under polymerization conditions. The catalyst system may optionally include an external electron donor, an activity limiter, and / or various other components.

[0141]

[0145] As used herein, a "cocatalyst" is a substance that can convert a procatalyst into an active polymerization catalyst. The cocatalyst may include aluminum, lithium, zinc, tin, cadmium, beryllium, hydrides, alkyls or aryls of magnesium, and combinations thereof. In one embodiment, the cocatalyst has the formula R 3Al [wherein each R is an alkyl, cycloalkyl, aryl or hydride group and at least one R is a hydrocarbyl group; two or three R radicals are connected in a cyclic radical to form a heterocyclic structure; each R may be the same or different; each R is a hydrocarbyl group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms] is a hydrocarbyl aluminum cocatalyst represented by. In a further embodiment, each alkyl group may be linear or branched, and such a hydrocarbyl group may be a mixed radical, i.e., the radical may contain alkyl, aryl, and / or cycloalkyl groups. Non-limiting examples of suitable radicals are methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, neopentyl, n-hexyl, 2-methylpentyl, n-heptyl, n-octyl, isooctyl, 2-ethylhexyl, 5,5-dimethylhexyl, n-nonyl, n-decyl, isodecyl, n-undecyl, n-dodecyl.

[0142]

[0146] Non-limiting examples of suitable hydrocarbyl aluminum compounds are triisobutylaluminum, tri-n-hexylaluminum, diisobutylaluminum hydride, di-n-hexylaluminum hydride, isobutylaluminum dihydride, n-hexylaluminum dihydride, diisobutylhexylaluminum, isobutyldihexylaluminum, trimethylaluminum, triethylaluminum, tri-n-propylaluminum, triisopropylaluminum, tri-n-butylaluminum, tri-n-octylaluminum, tri-n-decylaluminum, tri-n-dodecylaluminum. In one embodiment, preferred cocatalysts are selected from triethylaluminum, triisobutylaluminum, tri-n-hexylaluminum, diisobutylaluminum hydride, and di-n-hexylaluminum hydride, and the most preferred cocatalyst is triethylaluminum.

[0143]

[0147] In one embodiment, the cocatalyst is of the formula Rn AlX 3-n [wherein n = 1 or 2, R is alkyl, and X is halide or alkoxide] is a hydrocarbyl aluminum compound represented by. Non-limiting examples of suitable compounds are methylaluminoxane, isobutylaluminoxane, diethylaluminum ethoxide, diisobutylaluminum chloride, tetraethyldialuminoxane, tetraisobutyldialuminoxane, diethylaluminum chloride, ethylaluminum dichloride, methylaluminum dichloride, and dimethylaluminum chloride.

[0144]

[0148] In one embodiment, the catalyst composition includes an external electron donor. As used herein, an "external electron donor" is a compound added independently of procatalyst formation and contains at least one functional group capable of donating an electron pair to a metal atom. Without being bound by a particular theory, the external electron donor is thought to enhance the stereoselectivity of the catalyst (i.e., reduce the xylene soluble material in the formed polymer).

[0145]

[0149] In one embodiment, the external electron donor may be selected from one or more of alkoxysilanes, amines, ethers, carboxylates, ketones, amides, carbamates, phosphines, phosphates, phosphites, sulfonates, sulfones, and / or sulfoxides.

[0146]

[0150] In one embodiment, the external electron donor is an alkoxysilane. The alkoxysilane has the general formula: SiR m (OR’) 4-m (I) [wherein R is, independently at each occurrence, hydrogen or hydrocarbyl or amino group, optionally substituted with one or more substituents containing one or more heteroatoms of Group 14, 15, 16 or 17, and said R’ contains up to 20 atoms excluding hydrogen and halogen; R’ is a C 1-4 alkyl group; and m is 0, 1, 2 or 3]. In an embodiment, R is a C 6-12Aryl, alkyl or aralkyl, C 3-12 Cycloalkyl, C 3-12 Branched alkyl, or C 3-12 A cyclic or acyclic amino group, and R' is C 1-4 Alkyl, and m is 1 or 2. Non-limiting examples of suitable silane compositions include dicyclopentyldimethoxysilane, di-tert-butyldimethoxysilane, methylcyclohexyldimethoxysilane, methylcyclohexyldiethoxysilane, ethylcyclohexyldimethoxysilane, diphenyldimethoxysilane, diisopropyldimethoxysilane, di-n-propyldimethoxysilane, diisobutyldimethoxysilane, diisobutyldiethoxysilane, isobutylisopropyldimethoxysilane, di-n-butyldimethoxysilane, cyclopentyltrimethoxysilane, isopropyltrimethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, ethyltriethoxysilane, tetramethoxysilane, tetraethoxysilane, diethylaminotriethoxysilane, cyclopentylpyrrolidinodimethoxysilane, bis(pyrrolidino)dimethoxysilane, bis(perhydroisoquinolino)dimethoxysilane, and dimethyldimethoxysilane. In one embodiment, the silane composition is dicyclopentyldimethoxysilane (DCPDMS), methylcyclohexyldimethoxysilane (MChDMS), diisopropyldimethoxysilane (DIPDMS), n-propyltrimethoxysilane (NPTMS), diethylaminotriethoxysilane (DATES), or n-propyltriethoxysilane (PTES), and any combination thereof.

[0147]

[0151] In one embodiment, the external donor may be a mixture of at least two alkoxysilanes. In a further embodiment, the mixture may be dicyclopentyldimethoxysilane and methylcyclohexyldimethoxysilane, dicyclopentyldimethoxysilane and tetraethoxysilane, or dicyclopentyldimethoxysilane and n-propyltriethoxysilane.

[0148]

[0152] In one embodiment, the external electron donor is selected from one or more of benzoates and / or diol esters. In another embodiment, the external electron donor is 2,2,6,6-tetramethylpiperidine. In yet another embodiment, the external electron donor is a diether.

[0149]

[0153] In one embodiment, the catalyst composition includes an activity limiting agent (ALA). As used herein, "activity limiting agent" ("ALA") is a material that reduces catalyst activity at high temperatures (i.e., temperatures above about 85 °C). The ALA prevents or otherwise inhibits reactor fouling and ensures the continuity of the polymerization process. Typically, the activity of a Ziegler-Natta catalyst increases as the reactor temperature increases. Ziegler-Natta catalysts also typically maintain high activity near the melting point temperature of the polymer being produced. Heat generated by the exothermic polymerization reaction can cause polymer particles to agglomerate and ultimately lead to disruption of the polymer manufacturing process. The ALA reduces catalyst activity at high temperatures, thereby preventing reactor fouling, reducing (or preventing) particle agglomeration, and ensuring the continuity of the polymerization process.

[0150]

[0154] The activity limiting agent may be a carboxylic acid ester, a diether, a poly(alkene glycol), a poly(alkene glycol) ester, a diol ester, and combinations thereof. The carboxylic acid ester may be aliphatic or aromatic, or a mono- or poly-carboxylic acid ester. Non-limiting examples of suitable monocarboxylic acid esters include ethyl benzoate and methyl, ethyl p-methoxybenzoate, methyl p-ethoxybenzoate, ethyl p-ethoxybenzoate, ethyl acrylate, methyl methacrylate, ethyl acetate, ethyl p-chlorobenzoate, hexyl p-aminobenzoate, isopropyl naphthenate, n-amyl toluate, ethyl cyclohexanecarboxylate, and propyl pivalate.

[0151]

[0155] In one embodiment, the external electron donor and / or the activity limiting agent can be added separately to the reactor. In another embodiment, the external electron donor and the activity limiting agent can be premixed together and then added to the reactor as a mixture. In the mixture, a plurality of external electron donors or a plurality of activity limiting agents can be used. In one embodiment, the mixture is dicyclopentyldimethoxysilane and isopropyl myristate, dicyclopentyldiniethoxysilane and poly(ethylene glycol) laurate, dicyclopentyldimethoxysilane and isopropyl myristate and poly(ethylene glycol) dioleate, methylcyclohexyldimethoxysilane and isopropyl myristate, n-propyltrimethoxysilane and isopropyl myristate, dimethyldimethoxysilane and methylcyclohexyldimethoxysilane and isopropyl myristate, dicyclopentyldimethoxysilane and n-propyltriethoxysilane and isopropyl myristate, and dicyclopentyldimethoxysilane and tetraethoxysilane and isopropyl myristate, and combinations thereof.

[0152]

[0156] In one embodiment, the catalyst composition comprises any of the aforementioned external electron donors in combination with any of the aforementioned activity limiting agents.

[0157] The above-described catalyst system has been found to be particularly well-suited for the production of the heterogeneous polymer compositions of the present disclosure.

[0153]

[0158] Due to the physical properties of the polypropylene compositions of the present disclosure, the compositions described herein are well-suited for thermoforming and extrusion blow molding applications.

[0159] The present invention will be more readily understood by reference to the following examples, which are generally described and provided by way of illustration and are not intended to limit the present invention.

Examples

[0154]

[0160] Example 1

[0161] A variety of different heterophasic polypropylene copolymer samples were produced and tested for properties including impact strength and haze. Generally, the heterophasic copolymers were produced using the above process in combination with the above catalyst. In particular, the resins of the examples were prepared in a pilot plant of a two-stage reactor gas-phase fluidized bed. A Ziegler-Natta catalyst (CONSISTA® C601 Catalyst from W.R. Grace), a co-catalyst (triethylaluminum (TEAL)), an external donor (CONSISTA® D8700 Donor from W.R. Grace) and propylene were fed into the first reactor. For Examples 2-4, ethylene was fed into the first reactor. Hydrogen was also fed into the first reactor for all of the examples and was used to control the first polymer phase melt flow rate. The total reactor pressure was maintained constant using a nitrogen supply. In the first reactor, the polymer phase ethylene content was controlled by adjusting the ethylene / propylene gas-phase molar ratio, the melt flow rate was controlled by the hydrogen / propylene gas-phase molar ratio, and the low-temperature xylene soluble content was controlled by the co-catalyst / external donor molar ratio. The reactor temperature was maintained at 65°C.

[0155]

[0162] The first polymer phase powder was transferred from the first gas-phase reactor to the second gas-phase reactor and was also maintained at 65°C. The second reactor was fed with ethylene and propylene by controlling the propylene / ethylene gas-phase molar ratio and the hydrogen supply to control the second phase composition, and the melt flow rate was controlled by controlling the hydrogen / ethylene gas-phase molar ratio. Similar to the first reactor, nitrogen was supplied to maintain a constant reactor pressure.

[0156]

[0163] The additive package was mixed with the neat polymer produced in the reactor using a twin-screw extruder. The additive package included 1000 ppm of pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate); 1000 ppm of tris(2,4-di-tert-butylphenyl) phosphite; 180 ppm of acid scavenger DHT-4A obtained from Kisuma; 2000 ppm of glycerin monostearate; and 4000 ppm of nucleating agent commercially available from Milliken as MILLAD® NX® 8000. Test specimens were produced according to ASTM test D4101 to produce test specimens for testing. The test methods used were as described above.

[0157]

[0164] The following table shows the following polypropylene compositions produced and their properties.

[0158]

Table 1

[0159]

Table 2

[0160]

[0165] When comparing Composition 1 and Composition 2 with Comparative Example 1 (a material outside the scope of the ethylene / propylene copolymer disclosed herein), Compositions 1 and 2 exhibit higher toughness and comparable haze.

[0161]

[0166] When comparing Composition 3 and Composition 4 with Comparative Example 2 (a material outside the scope of the ethylene / propylene copolymer disclosed herein), Compositions 3 and 4 exhibit higher rigidity, as well as similar haze and toughness.

[0162]

[0167] When comparing Composition 1 and Composition 4 with Comparative Example 3, Compositions 1 and 4 exhibit somewhat lower but similar rigidity / toughness at room temperature, but improve the haze.

[0168] Paragraph 1. A polypropylene composition comprising: (a) A first polymer phase comprising a polypropylene homopolymer or random copolymer, wherein the polypropylene homopolymer or random copolymer optionally contains one or more comonomers in an amount of about 3% by weight or less based on the total weight of the propylene homopolymer or copolymer, has a total low temperature xylene soluble content of about 2% to about 6% by weight, and has a melt flow rate of about 0.5 g / 10 min to about 3 g / 10 min; a first polymer phase; (b) A second polymer phase comprising a propylene / ethylene copolymer, wherein the propylene / ethylene copolymer contains ethylene in an amount of less than about 18% by weight based on the total weight of the propylene / ethylene copolymer; a second polymer phase and comprising the ratio of the melt flow rate of the polypropylene homopolymer or random copolymer to the melt flow rate of the propylene / ethylene copolymer is greater than about 1.0; the first polymer phase and the second polymer phase together have a melt flow rate of about 4 g / 10 min or less, an ethylene content of less than about 5% by weight, a total low temperature xylene soluble content of about 5% to about 20% by weight, a haze at 1 mm of less than about 20%, an Izod impact strength at 23°C of greater than about 500 J / m, a Gardner falling impact strength at 0°C of greater than about 17 Nm (150 inch - pounds), and a flexural modulus of about 800 MPa or more, providing the polypropylene composition. A polypropylene composition.

[0163]

[0169] Paragraph 2. A polypropylene composition comprising: (a) A first polymer phase comprising a polypropylene homopolymer or random copolymer, wherein the polypropylene homopolymer or random copolymer optionally contains one or more comonomers in an amount of about 1 wt% or less based on the total weight of the propylene homopolymer or copolymer, has a total low temperature xylene soluble content of less than about 4 wt%, and has a melt flow rate of about 2 g / 10 min to about 5 g / 10 min, the first polymer phase, (b) A second polymer phase comprising a propylene / ethylene copolymer, wherein the propylene / ethylene copolymer contains ethylene in an amount of less than about 18 wt% based on the total weight of the propylene / ethylene copolymer, the second polymer phase comprising, the ratio of the melt flow rate of the polypropylene homopolymer or random copolymer to the melt flow rate of the propylene / ethylene copolymer is greater than about 1.0, the first polymer phase and the second polymer phase together have a melt flow rate of about 5 g / 10 min or less, an ethylene content of less than about 3.5 wt%, a total low temperature xylene soluble content of about 5 wt% to about 15 wt%, a haze at 1 mm of less than about 20%, an Izod impact strength at 23 °C of greater than about 200 J / m, and a flexural modulus of about 1100 MPa or more, providing the polypropylene composition, A polypropylene composition.

[0164]

[0170] Paragraph 3. The polypropylene composition according to Paragraph 1 or 2, wherein the first polymer phase comprises a crystalline matrix comprising the polypropylene homopolymer or random copolymer.

[0165]

[0171] Paragraph 4. The polypropylene composition according to any one of Paragraphs 1 to 3, comprising a heterophasic propylene copolymer.

[0172] Paragraph 5. The polypropylene composition according to any one of Paragraphs 1 and 3 to 4, wherein the first polymer phase comprises a polypropylene homopolymer or a random copolymer containing one or more comonomers in an amount of about 0 wt% to about 3 wt% based on the total weight of the propylene homopolymer or copolymer.

[0166]

[0173] Paragraph 6. The polypropylene composition according to any one of Paragraphs 1 and 3 to 5, wherein the first polymer phase comprises the polypropylene homopolymer or random copolymer having a total low-temperature xylene-soluble content of about 2.5 wt% or about 4.8 wt%.

[0167]

[0174] Paragraph 7. The polypropylene composition according to any one of Paragraphs 1 and 3 to 6, wherein the first polymer phase comprises the polypropylene homopolymer or random copolymer having a melt flow rate of about 0.5 g / 10 min to about 1.5 g / 10 min.

[0168]

[0175] Paragraph 8. The polypropylene composition according to any one of Paragraphs 1 and 3 to 7, having a melt flow rate of about 0.5 g / 10 min to about 1.5 g / 10 min.

[0169]

[0176] Paragraph 9. The polypropylene composition according to any one of Paragraphs 1 and 3 to 8, having an ethylene content of about 2 wt% to about 4.5 wt%.

[0177] Paragraph 10. The polypropylene composition according to any one of Paragraphs 1 and 3 to 9, having a total low-temperature xylene-soluble content of about 7 wt% or about 12 wt%.

[0170]

[0178] Paragraph 11. The polypropylene composition according to any one of Paragraphs 1 and 3 to 10, having a haze at 1 mm of about 5% to about 15%.

[0179] Paragraph 12. A polypropylene composition according to any one of paragraphs 1 and 3 to 11, having an Izod impact strength at 23°C of from about 500 J / m to about 900 J / m.

[0171]

[0180] Paragraph 13. A polypropylene composition according to any one of paragraphs 1 and 3 to 12, having a Gardner falling impact strength at 0°C of from about 17 Nm (150 inch - pounds) to about 39.6 Nm (350 inch - pounds).

[0172]

[0181] Paragraph 14. A polypropylene composition according to any one of paragraphs 1 and 3 to 13, having a flexural modulus of from about 800 MPa to about 1300 MPa.

[0182] Paragraph 15. The polypropylene composition according to any one of paragraphs 2 to 4, wherein the first polymer phase comprises the polypropylene homopolymer or random copolymer containing one or more comonomers in an amount of from about 0.5 wt% to about 1 wt% based on the total weight of the propylene homopolymer or copolymer.

[0173]

[0183] Paragraph 16. The polypropylene composition according to any one of paragraphs 2 to 4 and 15, wherein the first polymer phase comprises the polypropylene homopolymer or random copolymer having a total low - temperature xylene soluble content of from about 1 wt% to about 3 wt%.

[0174]

[0184] Paragraph 17. The polypropylene composition according to any one of paragraphs 2 to 4 and 15 to 16, wherein the first polymer phase comprises the polypropylene homopolymer or random copolymer having a melt flow rate of from about 2 g / 10 min to about 4 g / 10 min.

[0175]

[0185] Paragraph 18. A polypropylene composition according to any one of paragraphs 2 to 4 and 15 to 17, having a melt flow rate of from about 2 g / 10 min to about 4 g / 10 min.

[0176]

[0186] Paragraph 19. A polypropylene composition according to any one of Paragraphs 2 to 4 and 15 to 18, having an ethylene content of from about 2% by weight to about 3.5% by weight.

[0187] Paragraph 20. A polypropylene composition according to any one of Paragraphs 2 to 4 and 15 to 19, having a total low temperature xylene soluble content of about 5.5% by weight or about 12% by weight.

[0177]

[0188] Paragraph 21. A polypropylene composition according to any one of Paragraphs 2 to 4 and 15 to 20, having a haze at 1 mm of from about 10% to about 20%.

[0189] Paragraph 22. A polypropylene composition according to any one of Paragraphs 2 to 4 and 5 to 21, having an Izod impact strength at 23 °C of from about 200 J / m to about 900 J / m.

[0178]

[0190] Paragraph 23. A polypropylene composition according to any one of Paragraphs 2 to 4 and 5 to 22, having a flexural modulus of from about 1200 MPa to about 1600 MPa.

[0191] Paragraph 24. A polypropylene composition according to any one of Paragraphs 1 to 23, wherein the second polymer phase comprises a propylene / ethylene copolymer containing ethylene in an amount of from about 10% by weight to about 18% by weight based on the total weight of the propylene / ethylene copolymer.

[0179]

[0192] Paragraph 25. A polypropylene composition according to any one of Paragraphs 1 to 24, wherein the ratio of the melt flow rate of the polypropylene homopolymer or random copolymer to the melt flow rate of the propylene / ethylene copolymer is from about 1.0 to about 3.0.

[0180]

[0193] Paragraph 26. A polypropylene composition according to any one of Paragraphs 1 to 25, having a Gardner falling impact strength at 23 °C of greater than about 17 Nm (150 inch - pounds).

[0181]

[0194] Paragraph 27. The polypropylene composition according to any one of paragraphs 1 to 26, further comprising one or more of a nucleating agent, an acid neutralizing agent, and an antioxidant.

[0182]

[0195] Paragraph 28. The polypropylene composition according to paragraph 27, wherein the one or more nucleating agents are present in an amount of about 5000 ppm or less.

[0196] Paragraph 29. The polypropylene composition according to any one of paragraphs 1 to 28, wherein the one or more comonomers present in the polypropylene homopolymer or random copolymer contain ethylene.

[0183]

[0197] Paragraph 30. A molded article formed from the polypropylene composition according to any one of paragraphs 1 to 29.

[0198] Paragraph 31. The molded article according to paragraph 30, which is an extrusion blow molded article.

[0184]

[0199] Paragraph 32. A method for preparing the polypropylene composition according to any one of paragraphs 1 to 29 by sequential polymerization in the presence of a Ziegler-Natta catalyst, comprising the step of preparing a first polymer phase in a first gas phase reactor, transferring the first polymer phase to a second gas phase reactor containing a second polymer phase, and bringing the first polymer phase into contact with the second polymer phase to provide the polypropylene composition. Method.

[0185]

[0200] Paragraph 33. A method for preparing the polypropylene composition according to any one of paragraphs 1 to 29, Supplying propylene and optionally one or more comonomers into a first reactor, and supplying a catalyst mixture comprising (1) a Ziegler-Natta catalyst, (2) a cocatalyst, and (3) an external donor to the first reactor, Contacting the propylene with the catalyst mixture under first polymerization conditions to polymerize the propylene and optionally one or more comonomers to form a first polymer phase comprising a propylene homopolymer or copolymer, Transferring at least a portion of the first polymer phase to a second reactor, Supplying additional propylene and ethylene to the second reactor to form a second polymer phase and bringing about the polypropylene composition by combining the first polymer phase and the second polymer phase, method.

[0186]

[0201] Although specific embodiments are illustrated and described, it should be understood that changes and modifications can be made by those skilled in the art without departing from the broader aspects of the technology as defined in the following claims.

[0187]

[0202] The embodiments described herein as examples may be appropriately implemented without any element(s) and / or limitation(s) not specifically disclosed herein. Thus, for example, terms such as "comprising", "including", "containing", etc. shall be read extensionally and without limitation. Further, the terms and expressions used herein are used as terms of explanation rather than limitation, and there is no intention to exclude any equivalents of the features shown and described or parts thereof, but it is recognized that various modifications are possible within the scope of the claimed technology. Further, the phrase "consisting essentially of" is understood to include specifically recited elements and additional elements that do not substantially affect the basic and novel characteristics of the technology of the claims. The phrase "consisting of" excludes elements not specified.

[0188]

[0203] The present disclosure is not limited to the perspective of the specific embodiments described in this application. Many modifications and variations may be made without departing from the spirit and scope that will be apparent to those skilled in the art. Functionally equivalent methods and compositions within the scope of the present disclosure will be apparent to those skilled in the art from the foregoing description in addition to those listed herein. Such modifications and variations are intended to be within the scope of the appended claims. The present disclosure should be limited only by the terms of the appended claims together with the full scope of equivalents to which such claims are entitled. It should be understood that the present disclosure is of course not limited to the various specific methods, reagents, compounds, compositions or biological systems that may be possible. Also, it should be understood that the terms used herein are for the purpose of describing only specific embodiments and are not intended to be limiting.

[0189]

[0204] In addition, when features or aspects of the present disclosure are described in relation to a Markush group, one of ordinary skill in the art will recognize that the present disclosure is also thereby described in relation to any individual member of the Markush group or a subgroup of members of the Markush group.

[0190]

[0205] As will be understood by one of ordinary skill in the art, for all purposes, particularly in terms of providing a written description, all ranges disclosed herein also inherently include any and all possible subranges and combinations thereof. It can be readily recognized that any recited range can be fully described to enable the same range to be divided into at least equal halves, thirds, quarters, fifths, tenths, etc. By way of non-limiting example, each range discussed herein can be readily divided into upper, middle, and lower thirds. Also, as will be understood by one of ordinary skill in the art, all of the language such as "up to," "at least," "more than," "less than," etc. includes the recited number and inherently divides the range as a result into subranges as discussed above. Finally, as will be understood by one of ordinary skill in the art, ranges include each individual member.

[0191]

[0206] All publications, patent applications, issued patents, and other documents referred to herein are hereby incorporated by reference into this specification as if each individual publication, patent application, issued patent, or other document was specifically and individually indicated to be incorporated by reference in its entirety. Definitions contained in incorporated text are excluded to the extent that they contradict definitions in the present disclosure.

[0192]

[0207] Other embodiments are set forth in the following claims.

Claims

1. A polypropylene composition, (a) A first polymer phase comprising a polypropylene homopolymer or random copolymer, wherein the polypropylene homopolymer or random copolymer optionally contains one or more comonomers in an amount of about 3% by weight or less based on the total weight of the propylene homopolymer or copolymer, has a total low-temperature xylene soluble content of about 2% by weight to about 6% by weight, and has a melt flow rate of about 0.5 g / 10 min to about 3 g / 10 min, (b) A second polymer phase comprising a propylene / ethylene copolymer, wherein the propylene / ethylene copolymer contains less than 18% by weight of ethylene based on the total weight of the propylene / ethylene copolymer. Includes, The ratio of the melt flow rate of the polypropylene homopolymer or random copolymer to the melt flow rate of the propylene / ethylene copolymer is greater than approximately 1.

0. The present invention provides a polypropylene composition in which the first polymer phase and the second polymer phase combine to have a melt flow rate of about 4 g / 10 min or less, an ethylene content of less than 5% by weight, a total low-temperature xylene soluble content of about 5% to 20% by weight, a haze of less than 20% at 1 mm, an Izod impact strength at 23°C exceeding about 500 J / m, a Gardner drop impact strength at 0°C exceeding about 17 Nm (150 inch-pounds), and a flexural modulus of about 800 MPa or more. Polypropylene composition.

2. A polypropylene composition, (a) A first polymer phase comprising a polypropylene homopolymer or random copolymer, wherein the polypropylene homopolymer or random copolymer optionally contains one or more comonomers in an amount of about 1% by weight or less based on the total weight of the propylene homopolymer or copolymer, has a total low-temperature xylene soluble content of less than 4% by weight, and has a melt flow rate of about 2 g / 10 min to about 5 g / 10 min, (b) A second polymer phase comprising a propylene / ethylene copolymer, wherein the propylene / ethylene copolymer contains less than 18% by weight of ethylene based on the total weight of the propylene / ethylene copolymer. Includes, The ratio of the melt flow rate of the polypropylene homopolymer or random copolymer to the melt flow rate of the propylene / ethylene copolymer is greater than approximately 1.

0. The present invention provides a polypropylene composition in which the first polymer phase and the second polymer phase combine to have a melt flow rate of about 5 g / 10 min or less, an ethylene content of less than about 3.5% by weight, a total low-temperature xylene soluble content of about 5% to about 15% by weight, a haze of less than about 20% at 1 mm, an Izod impact strength at 23°C exceeding about 200 J / m, and a flexural modulus of about 1100 MPa or more. Polypropylene composition.

3. The polypropylene composition according to claim 1, wherein the first polymer phase comprises a crystalline matrix containing the polypropylene homopolymer or random copolymer.

4. The polypropylene composition according to claim 1, comprising a heterogeneous propylene copolymer.

5. The polypropylene composition according to claim 1, wherein the first polymer phase comprises a polypropylene homopolymer or random copolymer containing one or more comonomers in an amount of about 0% to about 3% by weight, based on the total weight of the propylene homopolymer or copolymer.

6. The first polymer phase comprises the polypropylene homopolymer or random copolymer having a total low-temperature xylene soluble content of about 2.5% by weight or about 4.8% by weight. The first polymer phase comprises the polypropylene homopolymer or random copolymer having a melt flow rate of about 0.5 g / 10 min to about 1.5 g / 10 min. It has a melt flow rate of approximately 0.5 g / 10 min to approximately 1.5 g / 10 min, and Having an ethylene content of approximately 2% to 4.5% by weight, The polypropylene composition according to claim 1.

7. The polypropylene composition according to claim 1, having a total low-temperature xylene soluble content of about 7% by weight or about 12% by weight.

8. The polypropylene composition according to claim 1, having approximately 5% to approximately 15% haze at 1 mm.

9. It has an Izod impact strength of approximately 500 J / m to approximately 900 J / m at 23°C, and It has a Gardner drop impact strength of approximately 17 Nm (150 inch-pounds) to approximately 39.6 Nm (350 inch-pounds) at 0°C. The polypropylene composition according to claim 1.

10. The polypropylene composition according to claim 1, having a flexural modulus of approximately 800 MPa to approximately 1300 MPa.

11. The first polymer phase comprises the polypropylene homopolymer or random copolymer having a total low-temperature xylene soluble content of about 1% to about 3% by weight. The first polymer phase comprises the polypropylene homopolymer or random copolymer having a melt flow rate of about 2 g / 10 min to about 4 g / 10 min. It has a melt flow rate of approximately 2 g / 10 min to approximately 4 g / 10 min, and Having an ethylene content of approximately 2% to 3.5% by weight, The polypropylene composition according to claim 2.

12. The polypropylene composition according to claim 2, having a total low-temperature xylene soluble content of approximately 5.5% by weight or approximately 12% by weight.

13. The polypropylene composition according to claim 2, having approximately 10% to approximately 20% haze at 1 mm.

14. It has an Izod impact strength of approximately 200 J / m to approximately 900 J / m at 23°C, and Having a flexural modulus of approximately 1200 MPa to approximately 1600 MPa, The polypropylene composition according to claim 2.

15. The polypropylene composition according to claim 1, wherein the second polymer phase comprises a propylene / ethylene copolymer containing ethylene in an amount of about 10% to about 18% by weight, based on the total weight of the propylene / ethylene copolymer.

16. The polypropylene composition according to claim 1, wherein the ratio of the melt flow rate of the polypropylene homopolymer or random copolymer to the melt flow rate of the propylene / ethylene copolymer is about 1.0 to about 3.

0.

17. A molded article formed from the polypropylene composition described in claim 1.

18. The molded article according to claim 17, which is an extruded blow-molded product.

19. A method for preparing the polypropylene composition described in claim 1 by stepwise polymerization in the presence of a Ziegler-Natta catalyst, The steps include preparing a first polymer phase in a first gas-phase reactor, The steps include transferring the first polymer phase to a second gas-phase reactor containing a second polymer phase, and Includes, By combining the first polymer phase with the second polymer phase, the polypropylene composition is obtained. method.

20. A method for preparing the polypropylene composition described in claim 1, The steps include supplying propylene and one or more comonomers optionally into a first reactor, and supplying a catalyst mixture comprising (1) a Ziegler-Natta catalyst, (2) a co-catalyst, and (3) an external donor to the first reactor, A step of contacting the propylene with the catalyst mixture under first polymerization conditions to polymerize the propylene and one or more comonomers to form a first polymer phase containing a propylene homopolymer or copolymer, The steps include transferring at least a portion of the first polymer phase to a second reactor, The steps include supplying additional propylene and ethylene to the second reactor to form a second polymer phase, and Includes, By combining the first polymer phase with the second polymer phase, the polypropylene composition is obtained. method.