Metallocene polypropylene composition

Abstract

Disclosed is a polymer composition comprising at least 95% by weight of a metallocene-catalyzed polypropylene and at least one of a clarifier or a nucleating agent. The polymer composition may have a lower haze value when compared to a second polymer composition having the same components in the same weight percent amounts as the polymer composition, but where the polypropylene in the composition is a Ziegler-Natta-catalyzed polypropylene. Haze values ​​may be determined according to ASTM D1003 at a thickness of 50 mils.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Application No. 63 / 398,336, filed August 16, 2022, the contents of which are incorporated herein by reference.

[0002] A. Field of the Invention The present invention generally relates to polypropylene compositions. In some embodiments, when the polypropylene is a metallocene-catalyzed polypropylene, a clarifying agent and / or a nucleating agent can be added to improve the clarity of the composition. The improved clarifying effect of these agents can be demonstrated by comparing their clarifying effect in metallocene-catalyzed polypropylene and non-metallocene-catalyzed polypropylene. [Background technology]

[0003] Polypropylene belongs to a family of polymers known as polyolefins and is one of the most widely used polymers today. Polypropylene is typically considered a commodity chemical and is mass-produced for the automotive, consumer goods, and furniture industries. As polypropylene technology has improved, its applications have expanded into specialized areas such as medical devices and aircraft parts.

[0004] Polypropylene is made from the polymerization of propene monomer (C3H6), typically involving the use of one of two types of catalysts: Ziegler-Natta or metallocene. Each propene monomer has a polymerizable element consisting of two carbon atoms and a double bond between them, and a pendant methyl group attached to one of the two carbon atoms. The monomeric polymerizable elements chemically react with each other to produce long hydrocarbon chains, with one pendant methyl group for every two carbon atoms in the chain.

[0005] Each propene monomer can be oriented in one of two ways during polymerization. As a result, the pendant methyl groups attached to each propene monomer are fixed in one of two orientations. The collective pattern of orientation of the pendant methyl groups along the polymer chain results in different basic chain structures. Isotactic polypropylene (iPP) has a uniform, repeating methyl group sequence with the methyl groups oriented on one side of the polymer chain. Syndiotactic polypropylene (sPP) has a uniform, alternating methyl group sequence with the methyl groups oriented alternately on both sides of the polymer chain. Atactic propylene (aPP) has an irregular pendant methyl group sequence with no orientation pattern. The overall orientation pattern of the pendant methyl groups affects the extent to which polymer chains can align with each other, a property known as crystallinity.

[0006] Polypropylene is a semi-crystalline polymer that contains ordered regions with aligned polymer chains and amorphous regions that lack a well-defined shape or morphology. The ordered, or crystalline, regions are called spherulites, which can be of various shapes and sizes, and amorphous regions exist between the crystalline regions. The degree of crystallinity can affect the polymer's characteristics, such as stiffness, as well as the material's chemical and heat resistance.

[0007] As polypropylene cools from the molten state to a solid, spherulite nucleation begins around microscopic sites naturally present in the material. The spherulites continue to grow around the nucleation sites, eventually growing larger than the wavelength of visible light. The large spherulites scatter light, resulting in a material that appears hazy. The hazy appearance can be undesirable for applications such as packaging, where visual appeal is a high priority. The haze of polypropylene can be a limiting factor for its inclusion in final products where clarity is desired. This haze can be more prevalent when polypropylene is formed (e.g., by injection molding) into thicker products compared to thin films. Summary of the Invention

[0008] A discovery has been made that provides a solution to the cloudy appearance associated with some types of polypropylene. In one aspect, it has been discovered that certain additives have different effects on polypropylene clarity, the effects depending, in part, on the type of catalyst used in synthesizing the polypropylene. Specifically, it has been discovered that additives such as nucleating agents and / or clarifiers, when combined with metallocene-catalyzed polypropylene, result in greater clarity compared to Ziegler-Natta-catalyzed polypropylene. The clarifying effects of these additives are attenuated when combined with Ziegler-Natta-catalyzed polypropylene. In certain embodiments, the fining agent can be a nonitol-based fining agent (e.g., 1,2,3,4-dibenzylidenesorbitol, 1,2,3,4-di-para-methylbenzylidenesorbitol, 1,2,3,4-di-meta,para-methylbenzylidenesorbitol, or 1,2,3-trideoxy-4,5:5,7-bis-O-[(4-propylphenyl)methylene]nonitol, etc.) or a trisamide-based fining agent (e.g., an amide derivative of 1,3,5-benzenetrisamide, preferably 1,3,5-tris(2,2-dimethylpropanamido)benzene, etc.). In certain embodiments, the nucleating agent can be a phosphate ester-based nucleating agent (e.g., 2,2′-methylenebis(4,6,-di-tertbutylphenyl)phosphate (phosphate ester), optionally in combination with a dispersant, etc.). As illustrated in the non-limiting examples, such combinations of clarifying and / or nucleating agents with metallocene-catalyzed polypropylene surprisingly resulted in improved clarity when compared to Ziegler-Natta-catalyzed polypropylene. This improved clarity broadens the applications and / or uses of the metallocene-catalyzed polypropylene compositions of the present invention. For example, the improved clarity can be particularly advantageous in applications where the polypropylene polymer is formed (e.g., by injection molding) into articles having a thickness of at least 2 mils, preferably at least 5 mils, more preferably at least 10 mils, or even more preferably between 20 mils and 300 mils, or even more preferably between 20 mils and 100 mils.

[0009] In one embodiment of the present invention, a polymeric composition is disclosed that includes at least 95% by weight of a metallocene-catalyzed polypropylene and at least one clarifier or nucleator. When compared to a second polymeric composition having the same components in the same weight percent amounts as the polymeric composition, but where the polypropylene in the composition is a Ziegler-Natta-catalyzed polypropylene, the polymeric composition has a lower haze value, as determined by ASTM D1003 at a thickness of 50 mils. Other thicknesses can also be tested to compare haze values ​​(e.g., 5, 10, 15, 20, 25, 30, 35, 40, 45, 55, 60, 65, 70, 75, or 80 mils). In some embodiments, the percent difference between the haze values ​​of the polymeric composition and the second polymeric composition increases as the amount of at least one clarifier or at least one nucleator increases. The polymeric composition can include 0.02% to 0.4% by weight of at least one clarifier or nucleator. In some particular embodiments, the clarifier may preferably be present at 0.2 wt.% to 0.4 wt.% (or any range or number therebetween, e.g., 0.2, 0.3, or 0.4 wt.%). In some particular embodiments, the nucleating agent may preferably be present at 0.02 wt.% to 0.2 wt.% (or any range or number therebetween, e.g., 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, or 0.2 wt.%).

[0010] When relating haze to the amount of at least one clarifier or nucleating agent in both polymer compositions, the compositions may exhibit one or more of the following characteristics: When both the polymer composition and the second polymer composition have 0.1 wt% of at least one clarifier or nucleating agent, the percentage difference between the haze values ​​of the polymer composition and the second polymer composition may be 10% to 25%. When both the polymer composition and the second polymer composition have 0.2 wt% of at least one clarifier or nucleating agent, the percentage difference between the haze values ​​of the polymer composition and the second polymer composition may be 45% to 60%. When both the polymer composition and the second polymer composition have 0.4 wt% of at least one clarifier or nucleating agent, the percentage difference between the haze values ​​of the polymer composition and the second polymer composition may be 90% to 105%. A suitable thickness for measuring these haze values ​​is a 50 mil molded plaque. However, as indicated above, other thicknesses can also be used to test the haze value.

[0011] In some embodiments, the metallocene-catalyzed polypropylene and the Ziegler-Natta-catalyzed polypropylene are each homopolymers. In other embodiments, the metallocene-catalyzed polypropylene and the Ziegler-Natta-catalyzed polypropylene are each random copolymers. In further embodiments, the metallocene-catalyzed polypropylene and the Ziegler-Natta-catalyzed polypropylene are blends of homopolymers and copolymers.

[0012] In some embodiments, the polymer composition includes at least one clarifying agent. In further embodiments, the clarifying agent is a nonitol-based clarifying agent or a trisamide-based clarifying agent. In certain embodiments, the nonitol-based clarifying agent is 1,2,3,4-dibenzylidene sorbitol, 1,2,3,4-di-para-methylbenzylidene sorbitol, 1,2,3,4-di-meta,para-methylbenzylidene sorbitol, or 1,2,3-trideoxy-4,5:5,7-bis-O-[(4-propylphenyl)methylene]nonitol. In other embodiments, the trisamide-based clarifying agent is an amide derivative of 1,3,5-benzenetrisamide, preferably 1,3,5-tris(2,2-dimethylpropanamido)benzene. In some embodiments, the clarifying agent is 1,2,3-trideoxy-4,5:5,7-bis-O-[(4-propylphenyl)methylene]nonitol.

[0013] In some embodiments, the polymer composition includes at least one nucleating agent. In certain embodiments, the nucleating agent is a phosphate ester-based nucleating agent. In certain embodiments, the phosphate ester-based nucleating agent includes 2,2'-methylenebis(4,6-di-tert-butylphenyl)phosphate (phosphate ester). In some embodiments, a dispersant can be included in the phosphate ester-based nucleating agent.

[0014] In some embodiments, the polymer composition has a melt flow index of 0.2 to 150 g / 10 min as measured by ASTM D1238 (230°C / 2.16 kg). In further embodiments, the polymer composition has a melt flow index of 5 to 100 g / 10 min, preferably about 20 to 30 g / 10 min, and a second polymer composition having the same components in the same weight percent amounts as the polymer composition but where the polypropylene in the composition is Ziegler-Natta catalyzed polypropylene has a melt flow index of 5 to 100 g / 10 min, preferably about 25 to 35 g / 10 min.

[0015] In some embodiments, the polymer composition further comprises an additive, which can be an antioxidant, an acid neutralizer, an antistatic agent, an antiblocking agent, an antifog agent, an anticorrosion agent, a UV absorber, a lubricant, a plasticizer, a mineral oil, a wax, a clay, talc, calcium carbonate, diatomaceous earth, carbon black, mica, glass fiber, an extender, a slip agent, a pigment, a UV stabilizer, a flame retardant, a mold release agent, a dye, a blowing agent, a fluorescent agent, a surfactant, or any combination thereof.

[0016] In some embodiments, the first polypropylene composition may have an elongation of 1% to 20%, preferably 3% to 10%, or more preferably about 7%, as measured by ASTM D3218, and / or a melting point of 125° C. to 175° C., preferably 140° C. to 160° C., or more preferably about 151° C., as measured by differential scanning calorimetry (DSC). The second polymer composition may have an elongation of 5% to 20%, preferably 10% to 15%, or more preferably about 12%, as measured by ASTM D638, and / or a melting point of 125° C. to 200° C., preferably 150° C. to 175° C., or more preferably about 165° C., as measured by differential scanning calorimetry (DSC).

[0017] In some embodiments of the present invention, the metallocene-catalyzed polypropylene composition, the Ziegler-Natta-catalyzed polypropylene composition, and / or articles formed from or including the metallocene-catalyzed or Ziegler-Natta-catalyzed polymerized compositions have a thickness of at least 2 mil, 3 mil, 4 mil, 5 mil, 6 mil, 7 mil, 8 mil, 9 mil, 10 mil, 15 mil, 20 mil, 25 mil, 30 mil, 35 mil, 40 mil, 45 mil, 50 mil, 55 mil, 60 mil, 65 mil, 70 mil, 75 mil, 80 mil, 85 mil, 90 mil, 95 mil, 100 mil, 110 mil, 120 mil, 130 mil, 140 mil, 150 mil, 160 mil, 170 mil, 180 mil, 190 mil, 210 mil, 220 mil, 230 mil, 240 mil, 250 mil, 260 mil, 270 mil, 280 mil, 290 mil, 300 mil, 310 mil, 320 mil, 330 mil, 340 mil, 350 mil, 360 mil, 370 mil, 380 mil, 390 mil, 400 mil, 410 mil, 420 mil, 430 mil, 440 mil, 450 mil, 460 mil, 470 mil, 480 mil, 490 mil, 510 mil, 520 mil The thickness may be 10 mil, 120 mil, 130 mil, 140 mil, 150 mil, 160 mil, 170 mil, 180 mil, 190 mil, 200 mil, 210 mil, 220 mil, 230 mil, 240 mil, 250 mil, 260 mil, 270 mil, 280 mil, 290 mil, 300 mil, 350 mil, 400 mil, or 500 mil, or more, or any range or number therebetween (e.g., a thickness of at least 5 mil, at least 10 mil, 20 mil to 300 mil, 20 mil to 100 mil, 40 mil to 100 mil, 40 mil to 80 mil, etc.). In some preferred embodiments, the thickness of the polypropylene composition or product of the present invention can be from 20 mil to 100 mil.

[0018] Also disclosed in the context of the present invention are articles of manufacture comprising the polymer compositions of the present invention. In some embodiments, a method of making the article comprises obtaining the polymer composition and making the article by injection molding, blow molding, compression molding, stretch molding, rotational molding, transfer molding, sheet extrusion thermoforming, shallow draw thermoforming, deep draw thermoforming, or profile extrusion.

[0019] Also disclosed is a method for producing the polypropylene composition of the present invention. The method includes obtaining a composition comprising at least 95% by weight of polypropylene and a clarifier and / or nucleating agent, and extruding the composition to obtain the polypropylene composition. In some embodiments, the extrusion conditions include a temperature of 200°C to 260°C.

[0020] Also disclosed within the context of the present invention are embodiments 1 through 24. Embodiment 1 is a polymer composition comprising: (a) at least 95 wt. % metallocene-catalyzed polypropylene; and (b) at least one clarifier or nucleator, wherein the polymer composition has a lower haze value when compared to a second polymer composition having the same components in the same wt. % amounts as the polymer composition, but where the polypropylene in the composition is Ziegler-Natta-catalyzed polypropylene, the haze value at a thickness of 50 mils as specified by ASTM D1003. Embodiments are the polymer composition of embodiment 1, wherein the % difference between the haze values ​​of the polymer composition and the second polymer composition increases as the amount of the at least one clarifier or the at least one nucleator increases. Example 3 is the polymer composition of Example 2, wherein the polymer composition comprises 0.02 wt. % to 0.4 wt. % of the at least one clarifier and / or the at least one nucleating agent, preferably 0.2 wt. % to 0.4 wt. % of the at least one clarifier and / or preferably 0.02 wt. % to 0.2 wt. % of the at least one nucleating agent.

[0013] Aspect 4 is the polymer composition of Aspect 3, wherein the percentage difference between the haze values ​​of the polymer composition and the second polymer composition when they each contain 0.1 wt% of the at least one clarifier or nucleator is 10% to 25%, the percentage difference between the haze values ​​of the polymer composition and the second polymer composition when they each contain 0.2 wt% of the at least one clarifier or nucleator is 45% to 60%, and / or the percentage difference between the haze values ​​of the polymer composition and the second polymer composition when they each contain 0.4 wt% of the at least one clarifier or nucleator is 90% to 105%. Aspect 5 is the polymer composition of any one of Aspects 1 to 4, wherein the metallocene-catalyzed polypropylene and the Ziegler-Natta-catalyzed polypropylene are each homopolymers. Example 6 is the polymer composition of any one of Examples 1-4, wherein the metallocene-catalyzed polypropylene and the Ziegler-Natta-catalyzed polypropylene are each a random copolymer.Aspect 7 is the polymer composition of any one of Aspects 1 to 4, wherein the metallocene-catalyzed polypropylene and the Ziegler-Natta-catalyzed polypropylene are blends of homopolymer and copolymer. Aspect 8 is the polymer composition of any one of Aspects 1 to 7, wherein the polymer composition includes at least one clarifier. Aspect 9 is the polymer composition of Aspect 8, wherein the clarifier is a nonitol-based clarifier or a trisamide-based clarifier. Example 10 is the polymer composition of Example 9, wherein the nonitol fining agent is 1,2,3,4-dibenzylidene sorbitol, 1,2,3,4-di-para-methylbenzylidene sorbitol, 1,2,3,4-di-meta,para-methylbenzylidene sorbitol, or 1,2,3-trideoxy-4,5:5,7-bis-O-[(4-propylphenyl)methylene]nonitol; or the trisamide fining agent is an amide derivative of 1,3,5-benzenetrisamide, preferably 1,3,5-tris(2,2-dimethylpropanamido)benzene. Example 11 is the polymer composition of Example 10, wherein the fining agent is 1,2,3-trideoxy-4,5:5,7-bis-O-[(4-propylphenyl)methylene]nonitol. Aspect 12 is the polymer composition of any one of Aspects 1-11, wherein the polymer composition includes at least one nucleating agent. Aspect 13 is the polymer composition of Aspect 12, wherein the nucleating agent is a phosphate ester nucleating agent. Aspect 14 is the polymer composition of Aspect 13, wherein the nucleating agent includes 2,2'-methylenebis(4,6-di-tert-butylphenyl)phosphate (phosphate ester) and, optionally, a dispersant. Aspect 15 is the polymer composition of any one of Aspects 1-14, wherein the polymer composition has a melt flow index of 0.2 to 150 g / 10 min as measured by ASTM D1238 (230°C / 2.16 kg).Aspect 16 is the polymer composition of Aspect 15, wherein the polymer composition has a melt flow index of 5 to 100 g / 10 min, preferably about 20 to 30 g / 10 min, and the second polymer composition has a melt flow index of 5 to 100 g / 10 min, preferably about 25 to 35 g / 10 min. Aspect 17 is the polymer composition of any one of Aspects 1 to 16, wherein the polymer composition further comprises an additive, the additive being an antioxidant, an acid neutralizer, an antistatic agent, an antiblocking agent, an antifogging agent, an anticorrosion agent, a UV absorber, a lubricant, a plasticizer, mineral oil, wax, clay, talc, calcium carbonate, diatomaceous earth, carbon black, mica, glass fiber, an extender, a slip agent, a pigment, a UV stabilizer, a flame retardant, a mold release agent, a dye, a blowing agent, a fluorescent agent, a surfactant, or any combination thereof. Example 18 is the polymer composition of any one of Examples 1-17, wherein the polymer composition has at least one of the following properties: an elongation of 1% to 20%, preferably 3% to 10%, or more preferably about 7%, as measured by ASTM D3218; and / or a melting point of 125°C to 175°C, preferably 140°C to 160°C, or more preferably about 151°C, as measured by differential scanning calorimetry (DSC); and / or the second polymer composition has at least one of the following properties: an elongation of 5% to 20%, preferably 10% to 15%, or more preferably about 12%, as measured by ASTM D638; and / or a melting point of 125°C to 200°C, preferably 150°C to 175°C, or more preferably about 165°C, as measured by differential scanning calorimetry (DSC). Example 19 is the polymer composition of any one of Examples 1-18, wherein the polymer composition has a thickness of at least 2 mils, preferably at least 5 mils, more preferably at least 10 mils, or even more preferably from 20 mils to 300 mils, or even more preferably from 20 mils to 100 mils. Example 20 is an article of manufacture comprising the polymer composition of any one of Examples 1-19. Example 21 is the article of Example 20, wherein the article is an injection molded article and preferably has a thickness of from 20 mils to 100 mils.

[0021] Example 22 is a method of making the product of example 21, the method comprising obtaining the polymer composition of any one of examples 1-19 and forming the product by injection molding, blow molding, compression molding, stretch molding, rotational molding, transfer molding, sheet extrusion thermoforming, shallow draw thermoforming, deep draw thermoforming, or profile extrusion. Example 23 is a method of producing the polymer composition of any one of examples 1-19, the method comprising (a) obtaining a composition comprising at least 95 wt% polypropylene and a clarifier or nucleator, and (b) extruding the composition to obtain the polymer composition of any one of examples 1-19. Example 24 is the method of example 23, wherein the extrusion conditions comprise a temperature of 200°C to 260°C.

[0022] Other aspects or embodiments of the invention are discussed throughout this application. Any aspect or embodiment discussed with respect to one aspect of the invention also applies to other aspects or embodiments of the invention, and vice versa. Each aspect or embodiment described herein is to be construed as an aspect or embodiment of the invention that is applicable to other aspects of the invention. It is contemplated that any aspect or embodiment discussed herein can be combined with other aspects or embodiments discussed herein and / or implemented with respect to any method or composition of the invention, and vice versa. Furthermore, the compositions and systems of the invention can be used to achieve the methods of the invention.

[0023] Listed below are definitions of terms and phrases used throughout this specification.

[0024] The terms "about" or "approximately" are defined as approximations as understood by one of ordinary skill in the art. In one non-limiting embodiment, these terms are defined as within 10%, alternatively within 5%, alternatively within 1%, or alternatively within 0.5%.

[0025] The terms "wt. %, "vol. %, " or "mole %" refer to the weight percentage of a component, the volume percentage of a component, or the mole percentage of a component, respectively, based on the total weight, total volume of material, or total moles, including that component. In a non-limiting example, 10 grams of a component in 100 grams of material is 10% of that component by weight. The term "ppm" refers to parts per million by weight of that component, based on the total weight, including that component.

[0026] The term "substantially" and variations thereof are defined to include ranges of within 10%, within 5%, within 1%, or within 0.5%.

[0027] The terms "inhibit" or "reduce" or "prevent" or "avoid" or any variations of these terms, when used in the claims and / or specification, include any measurable reduction or complete inhibition that achieves the desired result.

[0028] The term "effective," as used in the specification and / or claims, means adequate to accomplish a desired, expected, or intended result.

[0029] The use of the words "a" or "an," when used in conjunction with any of the terms "comprising," "including," "containing," or "having" in the claims or specification, can mean "one," but is also consistent with the meanings of "one or more," "at least one," and "one or more than one."

[0030] The phrase "and / or" can include "and" or "or." For purposes of illustration, X, Y, and / or Z can include: X alone, Y alone, Z alone, a combination of X and Y, a combination of X and Z, a combination of Y and Z, or a combination of X, Y, and Z.

[0031] The words "comprising" (and any of its forms, e.g., "comprise" and "comprises"), "having" (and any of its forms, e.g., "have" and "has"), "including" (and any of its forms, e.g., "includes" and "include"), or "containing" (and any of its forms, e.g., "contains" and "contain") are inclusive or open-ended and do not exclude additional, unrecited elements or method steps.

[0032] The processes and systems of the present invention may "comprise," "consist essentially of," or "consist of" certain components, elements, compositions, steps, etc., disclosed throughout this specification. With respect to the transitional phrase "consist essentially of," in one non-limiting aspect, basic and novel properties of the compositions and processes of the present invention include the improved clarity of metallocene-catalyzed polypropylene compositions compared to Ziegler-Natta-catalyzed polypropylene compositions through the use of nucleating and clarifying agents.

[0033] Other objects, features, and advantages of the present invention will become apparent from the following detailed description and examples. However, it should be understood that the detailed description and examples, while indicating specific embodiments of the present invention, are given by way of illustration only and are not meant to be limiting. It is also contemplated that changes and modifications within the spirit and scope of the present invention will become apparent to those skilled in the art from this detailed description. In further embodiments, features of specific embodiments can be combined with features of other embodiments. For example, features of one embodiment can be combined with features of any of the other embodiments. In further embodiments, additional features can be added to the specific embodiments described herein. DETAILED DESCRIPTION OF THE INVENTION

[0034] One aspect of the present invention is based on the discovery that a clarifier and / or nucleating agent provides targeted improvements in the clarity of metallocene-catalyzed polypropylene compositions. The improvement in clarity is surprising and unexpected in that the degree of clarity improvement is greater than in other polypropylene compositions, such as Ziegler-Natta-catalyzed compositions. In a side-by-side comparison of polypropylene compositions produced using different catalysts, the addition of a clarifier or nucleating agent selectively imparted lower haze to the metallocene-catalyzed polypropylene. The non-limiting data in the Examples section supports this finding. These and other non-limiting aspects of the present invention are discussed in more detail in the following sections.

[0035] A. Polypropylene Polypropylene polymers can include homopolymers of polypropylene (e.g., isotactic, syndiotactic, and atactic polypropylene), copolymers of propylene with other olefins, and terpolymers of propylene, ethylene, and / or dienes. In some instances, controlled rheology grade polypropylene (CRPP) can be used. CRPP is polypropylene that has been further processed (e.g., through a degradation process) to produce a polypropylene polymer with a desired high melt flow index (MFI), a lower molecular weight than the starting polypropylene, and / or a narrow molecular weight distribution.

[0036] Polypropylene can be prepared by any of the commercially available polymerization processes (e.g., "high pressure," slurry, solution, and / or gas phase processes). Polypropylene can be prepared using methods described in U.S. Patent Nos. 8,957,159, 8,088,867, 8,071,687, 7,056,991, and 6,653,254. Polypropylene can also be purchased from commercial sources, such as TotalEnergies (USA), Total SA, LyondellBasell Industries, Reliance Industries Ltd, Sinopec, and ExxonMobil Chemical Co. Polypropylene can be pre-stretched and / or in a solid form, such as pellets. A non-limiting example of a polypropylene polymer that can be used in the present invention is M3766, a metallocene-catalyzed polypropylene homopolymer having a melt index (2.16 kg-230°C) of 24 g / 10 min as determined by ASTM D-1238, a density of 0.9 g / cc as determined by ASTM D-1505, and a melting point of 151°C (304°F) as determined by differential scanning calorimetry. A non-limiting example of a polypropylene polymer that can be used to evaluate the effectiveness of clarification and nucleating additives for metallocene-catalyzed polypropylene is 3825, a Ziegler-Natta-catalyzed polypropylene homopolymer with a melt index (2.16 kg-230°C) of 30 g / 10 min as determined by ASTM D-1238, a density of 0.9 g / cc as determined by ASTM D-1505, and a melting point of 165°C (330°F) as determined by differential scanning calorimetry.

[0037] B. First Polypropylene Composition (Metallocene-Catalyzed Polypropylene Composition) The first polypropylene composition can contain at least 95 wt% metallocene-catalyzed polypropylene and at least one of a clarifier and a nucleating agent. The first polypropylene composition can contain 95 wt% to 100 wt%, or a wt% equal to, at least, up to, or between any two of 95, 96, 97, 98, 99, 99.1, 99.2, 99.3, 99.4, 99.5, 99.6, 99.7, 99.8, 99.9, 99.95, and 100 wt%, based on the total weight of the first composition. The polypropylene in the first polypropylene composition can be a homopolymer, a random copolymer, or a blend of a homopolymer and a copolymer. In certain embodiments, the first polypropylene composition has a melt flow index of 5 to 100 g / 10 min, preferably about 20 to 30 g / 10 min. In certain embodiments, the first polypropylene composition can have any one, any combination, or all of the following: i) an elongation of from 1% to 20%, preferably from 3% to 10%, or more preferably about 7%, as measured by ASTM D3218, and ii) a melting point of from 125°C to 175°C, preferably from 140°C to 160°C, or more preferably about 151°C, as measured by differential scanning calorimetry (DSC).

[0038] C. Second comparative polypropylene composition (Ziegler-Natta catalyst polymerized polypropylene composition) The second polypropylene composition is a comparative composition that can be used to compare the anti-haze effect of a clarifier or nucleating agent on different polypropylene compositions. The second polypropylene composition can be a Ziegler-Natta catalyzed polypropylene. In some embodiments, the second polymer composition has the same components and weight percent amounts as the first polymer composition, except that the polypropylene in the second polymer composition is a Ziegler-Natta catalyzed polypropylene. The polypropylene in the second polypropylene composition can be a homopolymer, a random copolymer, or a blend of a homopolymer and a copolymer. In certain embodiments, the second polypropylene composition has a melt flow index of 5 to 100 g / 10 min, preferably about 25 to 35 g / 10 min. In certain embodiments, the second polypropylene composition can have any one, any combination, or all of the following: i) an elongation of from 5% to 20%, preferably from 10% to 15%, or more preferably about 12%, as measured by ASTM D3218, and ii) a melting point of from 125°C to 200°C, preferably from 150°C to 175°C, or more preferably about 165°C, as measured by differential scanning calorimetry (DSC).

[0039] D. Clarifying Agent The polypropylene composition of the present invention can include a clarifier or a combination of clarifiers. The clarifier can include a trisamide-based clarifier, a nonitol-based clarifier, and / or a sorbitol-based clarifier, or any combination thereof. The trisamide clarifier can include, but is not limited to, an amide derivative of benzene-1,3,5-tricarboxylic acid, an amide derivative of 1,3,5-benzenetriamine, a derivative of N-(3,5-bis-formylamino-phenyl)-formamide, a derivative of 2-carbamoyl-malonamide, and any combination thereof. In a specific embodiment, the trisamide clarifier is N,N',N''-benzene-1,3,5-triyltris(2,2-dimethylpropanamide). Nonitol-based fining agents include, but are not limited to, nonitol derivatives, such as 1,2,3-trideoxy-4,5:5,7-bis-O-[(4-propylphenyl)methylene]nonitol (NX8000, CAS Registry Number 882073-43-0, Milliken Chemical, Spartanburg, SC). Sorbitol fining agents include, but are not limited to, 1,2,3,4-dibenzylidene sorbitol (Millad 3905, CAS#: 32647-67-9, Milliken Chemical, Spartanburg, SC), 1,2,3,4-di-para-methylbenzylidene sorbitol (Millad 3940 CAS#: 54686-97-4, Milliken Chemical, Spartanburg, SC), and 1,2,3,4-di-meta,para-methylbenzylidene sorbitol (Millad 3998, CAS#: 135861-56-2, Milliken Chemical, Spartanburg, SC). Another fining agent that can be used in the context of the present invention is NA-71 (ADK STAB NA-71) (Adeka Corporation, Tokyo, Japan).In some preferred embodiments, the fining agent is 1,2,3-trideoxy-4,5:5,7-bis-O-[(4-propylphenyl)methylene]nonitol (NX8000, CAS Registry Number 882073-43-0, Milliken Chemical, Spartanburg, SC). In other preferred embodiments, the fining agent is an amide derivative of 1,3,5-benzenetrisamide, preferably 1,3,5-tris(2,2-dimethylpropanamido)benzene (Irgacelar XT 386, BASF, Ludwigshafen, Germany).

[0040] In some preferred embodiments, the fining agent is a nonitol-based fining agent, preferably 1,2,3-trideoxy-4,5:5,7-bis-O-[(4-propylphenyl)methylene]nonitol (NX8000, CAS Registry Number 882073-43-0, Milliken Chemical, Spartanburg, SC).

[0041] Amounts of clarifying agent that can be included in the polypropylene composition of the present invention include 0.01 wt.% to 5 wt.%, or any amount or range therebetween (e.g., 0.01 wt.%, 0.05 wt.%, 0.1 wt.%, 0.2 wt.%, 0.3 wt.%, 0.4 wt.%, 0.5 wt.%, 0.6 wt.%, 0.7 wt.%, 0.8 wt.%, 0.9 wt.%, 1 wt.%, 1.5 wt.%, 2 wt.%, 2.5 wt.%, 3 wt.%, 3.5 wt.%, 4 wt.%, 4.5 wt.%, 5 wt.%). In some preferred embodiments, the polypropylene composition of the present invention can include clarifier(s) in an amount of 0.01 wt.% to 0.5 wt.%, or any amount or range therebetween (e.g., 0.01 wt.%, 0.02 wt.%, 0.03 wt.%, 0.04 wt.%, 0.05 wt.%, 0.06 wt.%, 0.07 wt.%, 0.08 wt.%, 0.09 wt.%, 0.1 wt.%, 0.2 wt.%, 0.3 wt.%, 0.4 wt.%, or 0.5 wt.%).

[0042] E. Nucleating Agent The polypropylene composition of the present invention can include a nucleating agent or a combination of nucleating agents. Nucleating agents can include phosphate ester nucleating agents. Non-limiting examples of phosphate ester nucleating agents include 2,2'-methylenebis(4,6-di-tert-butylphenyl)phosphate or Hyperform HPN 715 (Milliken Chemical, Spartanburg, SC). 2,2'-methylenebis(4,6-di-tert-butylphenyl)phosphate is also commercially available from Adeka (Tokyo, Japan) under the trademarks ADK STAB NA-11 or ADK STAB NA-27. NA-27 is a combination of NA-11 and a dispersant. In other examples, the nucleating agent can be a non-phosphate ester nucleating agent (e.g., bicyclo[2.2.1]heptane-2,3-dicarboxylic acid disodium salt or Hyperform HPN 68L (Milliken Chemical, Spartanburg, SC)).

[0043] Amounts of nucleating agent that can be included in the polypropylene composition of the present invention include 0.01 wt.% to 5 wt.%, or any amount or range therebetween (e.g., 0.01 wt.%, 0.05 wt.%, 0.1 wt.%, 0.2 wt.%, 0.3 wt.%, 0.4 wt.%, 0.5 wt.%, 0.6 wt.%, 0.7 wt.%, 0.8 wt.%, 0.9 wt.%, 1 wt.%, 1.5 wt.%, 2 wt.%, 2.5 wt.%, 3 wt.%, 3.5 wt.%, 4 wt.%, 4.5 wt.%, 5 wt.%). In some preferred embodiments, the polypropylene composition of the present invention can include 0.01 wt.% to 0.5 wt.% of a nucleating agent, or any amount or range therebetween (e.g., 0.01 wt.%, 0.02 wt.%, 0.03 wt.%, 0.04 wt.%, 0.05 wt.%, 0.06 wt.%, 0.07 wt.%, 0.08 wt.%, 0.09 wt.%, 0.1 wt.%, 0.2 wt.%, 0.3 wt.%, 0.4 wt.%, or 0.5 wt.%).

[0044] F. Additives The first polypropylene composition and the second polypropylene composition of the present invention can contain various additives. Non-limiting examples of additives include dispersants, antiblocking agents, antistatic agents, antioxidants, neutralizing agents, antistatic agents, antifog agents, anticorrosion agents, lubricants, plasticizers, mineral oil, wax, clay, talc, calcium carbonate, diatomaceous earth, carbon black, mica, glass fibers, blowing agents, crystallization aids, dyes, flame retardants, extenders, impact modifiers, mold release agents, oils, other polymers, dyes, pigments, processing agents, reinforcing agents, slip agents, fluorescent agents, surfactants, flame retardants, flow control agents, stabilizers, UV resistant agents, and combinations thereof. Additives are available from various commercial sources. Non-limiting examples of additive commercial sources include BASF (Germany), Dover Chemical Corporation (USA), AkzoNobel (Netherlands), Sigma-Aldrich® (USA), Atofina Chemicals, Inc., etc. The amount of additive can range from 0.01 wt.% to 5 wt.% (e.g., 0.01 wt.%, 0.05 wt.%, 0.1 wt.%, 0.2 wt.%, 0.3 wt.%, 0.4 wt.%, 0.5 wt.%, 0.6 wt.%, 0.7 wt.%, 0.8 wt.%, 0.9 wt.%, 1 wt.%, 1.5 wt.%, 2 wt.%, 2.5 wt.%, 3 wt.%, 3.5 wt.%, 4 wt.%, 4.5 wt.%, 5 wt.%, or any amount or range therebetween) in the first polypropylene composition and / or the second polypropylene composition. In some embodiments, for the purpose of controlling disparate additive / amount effects, the additive(s) and additive amount(s) added to the first polypropylene composition should be the same as the additive(s) and additive amount(s) added to the second polypropylene composition.

[0045] G. Methods for Preparing Polymer Compositions The first and second polymer compositions of the present invention can be made by blending polypropylene (metallocene-catalyzed polypropylene for the first composition and Ziegler-Natta-catalyzed polypropylene for the second composition) with a clarifier and / or nucleating agent, and optionally other additives. In some embodiments, the polypropylene can be in a solid form (e.g., pellets) and melted and mixed with the clarifier and / or nucleating agent and optional other additives. Suitable blending machinery is known to those skilled in the art. Non-limiting examples include mixers, kneaders, and extruders. In certain embodiments, the process can be carried out using an extruder by introducing the polypropylene and the clarifier and / or nucleating agent and other additives into the extruder hopper. Non-limiting examples of extruders include single-screw extruders, counter-rotating and co-rotating twin-screw kneading extruders, planetary gear extruders, ring extruders, or co-kneaders. Melt mixing can be carried out at a melt temperature of 200°C to 260°C, or at a temperature equal to, up to, or between any one of 200°C, 205°C, 210°C, 215°C, 220°C, 225°C, 230°C, 235°C, 240°C, 245°C, 250°C, 255°C, and 260°C. The polypropylene and clarifiers and / or nucleating agents and other additives can be subjected to elevated temperatures for a sufficient length of time during mixing. The mixing temperature can be above the softening point of the polypropylene.

[0046] The clarifier and / or nucleating agent and other additives can be premixed or added separately to the polypropylene. For example, the clarifier and / or nucleating agent and other additives can be premixed as they are added to the polypropylene. The clarifier and nucleating agent and other additives can be incorporated into the polypropylene, for example, by mixing the above components using methods conventional in process technology. The mixing temperature can be higher than the softening point of the polypropylene. In certain embodiments, the process can be carried out at a temperature of about 160°C to 250°C. Such "melt mixing" or "melt compounding" results in a uniform dispersion of the additives present in the polypropylene.

[0047] H.Product The polymer compositions of the present invention can be incorporated into articles of manufacture. In some embodiments, the articles can be extruded articles, blow molded articles, rotational molded articles, injection molded articles, and / or thermoformed articles. In some embodiments, the articles can be transparent. Non-limiting examples of articles include films, sheets, fibers, yarns, packaging fillers, forming films, protective packaging, shrink sleeves and / or labels, shrink films, twist wraps, sealant films, caps, crates, bottles, jars, funnels, pipette tips, well plates, microtiter plates, syringes, sutures, face masks, personal protective equipment, medical instruments, medical trays, sample vials, cuvettes, reaction vials, contact lens molds, cigarette filters, industrial filters, knitted socks, winter and summer Examples of applications include sportswear, underwear, shoes, rope, twine, bale packaging, tape, architectural / industrial fabrics, pipes, non-electrical fuses for explosives, absorbent products (e.g., diapers), expandable foams, carpets, mats, rugs, furniture, toys, luggage, tote bags, duffel bags, sports bags, backpacks, textiles, food containers, food lids, prepared food containers and lids, dairy containers and lids, vehicle parts, dashboards, bumpers, cladding, exterior trim, film cushioning, film skins, covers, and interior vehicle components. In these and other applications, the resins can be combined with other materials, such as particulate materials, to form composites, including talc, calcium carbonate, wood, and fibers, such as glass or graphite fibers. Examples of such composites include furniture parts, automotive parts, and building materials, particularly those used as lumber substitutes. [Example]

[0048] The present invention will now be described in more detail with reference to specific examples. The following examples are provided for illustrative purposes only and are not intended to limit the present invention in any way. Those skilled in the art will readily recognize a variety of non-critical parameters that can be changed or modified to yield essentially the same results.

[0049] A. Example 1 - (Preparation of Ziegler-Natta Catalyst-Polypropylene Composition Using Nucleating Agent) The polypropylene composition of Example 1 was made by adding a nucleating agent (NA27, 0.1 wt%) directly to Ziegler-Natta catalyzed polypropylene (3825, 99.9 wt%) and mixing the two materials together using a 1 1 / 4 inch Welex extruder at a speed of 30 pph and a melt temperature of 400°F.

[0050] B. Example 2 - (Preparation of Metallocene-Catalyzed Polypropylene Composition Using a Nucleating Agent) The polypropylene composition of Example 2 was made by adding a nucleating agent (NA27, 0.1 wt%) directly to metallocene-catalyzed polypropylene (M3766, 99.9 wt%) and mixing the two materials together using a 1 1 / 4 inch Welex extruder at a speed of 30 pph and a melt temperature of 400°F.

[0051] C. Example 3 - (Preparation of Ziegler-Natta catalyzed polypropylene composition using a clarifier) The polypropylene composition of Example 3 was made by adding a clarifier (NX8000, 0.2 wt%) directly to Ziegler-Natta catalyzed polypropylene (3825, 99.8 wt%) and mixing the two materials together using a 1 1 / 4 inch Welex extruder at a speed of 30 pph and a melt temperature of 400°F.

[0052] D. Example 4 - (Preparation of Metallocene-Catalyzed Polypropylene Composition Using a Clarifying Agent) The polypropylene composition of Example 4 was made by adding a clarifier (NX8000, 0.2 wt%) directly to metallocene-catalyzed polypropylene (M3766, 99.8 wt%) and mixing the two materials together using a 1 1 / 4 inch Welex extruder at a speed of 30 pph and a melt temperature of 400°F.

[0053] E. Example 5 - (Preparation of Ziegler-Natta catalyzed polypropylene composition using a clarifier) The polypropylene composition of Example 5 was made by adding a clarifier (NX8000, 0.4 wt%) directly to Ziegler-Natta catalyzed polypropylene (3825, 99.6 wt%) and mixing the two materials together using a 1 1 / 4 inch Welex extruder at a speed of 30 pph and a melt temperature of 400°F.

[0054] F. Example 6 - (Preparation of Metallocene-Catalyzed Polypropylene Composition Using a Clarifying Agent) The polypropylene composition of Example 6 was made by adding a clarifier (NX8000, 0.4 wt%) directly to metallocene-catalyzed polypropylene (M3766, 99.6 wt%) and mixing the two materials together using a 1 1 / 4 inch Welex extruder at a speed of 30 pph and a melt temperature of 400°F.

[0055] G. Example 7 - (Haze Values ​​of Compositions of Examples 1 to 6) Tables 1 and 2 show data on the haze values ​​of the polypropylene compositions of Examples 1 to 6. [Table 1] [Table 2]

[0056] Table 1 depicts various polypropylene compositions that were prepared. The polypropylene compositions included either metallocene-catalyzed polypropylene or Ziegler-Natta-catalyzed polypropylene in combination with various amounts of either a clarifier or a nucleating agent. The compositions were molded into 50 mil thick lids and then tested for haze.

[0057] Table 2 contains the haze values ​​for various polypropylene compositions. A comparison of Examples 1 and 2 shows that equal amounts of nucleating agent resulted in higher clarity (i.e., lower cloudiness) for the metallocene-catalyzed polymerized material. A comparison of Examples 3 and 4 shows that equal amounts of clarifying agent also resulted in higher clarity for the metallocene-catalyzed polymerized material. A greater improvement in clarity for the metallocene-catalyzed polymerized material was also observed when comparing Examples 5 and 6.

[0058] A comparison of metallocene-catalyzed Examples 4 and 6 shows that higher clarifier loadings resulted in greater clarity. The net reduction in haze between Examples 5 and 6 (using 0.4% clarifier) ​​is greater than the corresponding reduction in haze observed between Examples 3 and 4 (using 0.2% clarifier). These results indicate that the improvement in clarity is more rapid with increasing additive concentration (from 0.2% to 0.4%). Taken together, these results demonstrate that a significant clarification effect is observed when a nucleating or clarifying additive is used in metallocene-catalyzed polypropylene compositions. The clarification effect is greater in metallocene-catalyzed polypropylene compositions than in Ziegler-Natta-catalyzed polypropylene compositions. ****

[0059] While the embodiments of the present application and their advantages have been described in detail, it should be understood that various changes, substitutions, and alterations can be made therein without departing from the spirit and scope of the present invention as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the processes, machines, manufacture, compositions of matter, means, methods, and steps described in the specification. As those skilled in the art will readily recognize from the above disclosure, existing or later-developed processes, machines, manufacture, compositions of matter, means, methods, or steps can be utilized that perform substantially the same function or bring about substantially the same results as the relevant embodiments described herein. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.

Claims

1. 1. A polymer composition comprising: (a) at least 95% by weight of metallocene-catalyzed polypropylene; and (b) at least one of a fining agent or a nucleating agent; Including, the polymer composition has a lower haze value when compared to a second polymer composition having the same components in the same weight percent amounts as the polymer composition but where the polypropylene in the composition is Ziegler-Natta catalyzed polypropylene, and the haze value is determined by ASTM D1003 at a thickness of 50 mils; The polymer composition.

2. 10. The polymer composition of claim 1, wherein the % difference between the haze values ​​of the polymer composition and the second polymer composition increases with increasing amounts of the at least one fining agent or the at least one nucleating agent.

3. 3. The polymer composition according to claim 2, wherein the polymer composition comprises 0.02 to 0.4 wt.% of said at least one clarifier and / or said at least one nucleating agent, preferably 0.2 to 0.4 wt.% of said at least one clarifier and / or preferably 0.02 to 0.2 wt.% of said at least one nucleating agent.

4. 4. The polymer composition of claim 3, the percentage difference between the haze values ​​of the polymer composition and the second polymer composition is between 10% and 25% when both polymer compositions have 0.1 wt. % of the at least one fining or nucleating agent; the percentage difference between the haze values ​​of the polymer composition and the second polymer composition is between 45% and 60% when both polymer compositions have 0.2 wt. % of the at least one fining or nucleating agent; and / or the percentage difference between the haze values ​​of the polymer composition and the second polymer composition is 90% to 105% when both polymer compositions have 0.4 wt.% of the at least one fining or nucleating agent; The polymer composition.

5. The polymer composition according to any one of claims 1 to 4, wherein the metallocene-catalyzed polypropylene and the Ziegler-Natta-catalyzed polypropylene are each a homopolymer.

6. The polymer composition according to any one of claims 1 to 4, wherein the metallocene-catalyzed polypropylene and the Ziegler-Natta-catalyzed polypropylene are each a random copolymer.

7. The polymer composition according to any one of claims 1 to 4, wherein the metallocene-catalyzed polypropylene and the Ziegler-Natta-catalyzed polypropylene are blends of homopolymers and copolymers.

8. The polymer composition according to any one of claims 1 to 4, wherein said polymer composition comprises said at least one clarifier.

9. 9. The polymer composition of claim 8, wherein the clarifier is a nonitol-based clarifier or a trisamide-based clarifier.

10. 10. The polymer composition of claim 9, the nonitol fining agent is 1,2,3,4-dibenzylidene sorbitol, 1,2,3,4-di-para-methylbenzylidene sorbitol, 1,2,3,4-di-meta,para-methylbenzylidene sorbitol, or 1,2,3-trideoxy-4,5:5,7-bis-O-[(4-propylphenyl)methylene]nonitol; or The trisamide-based fining agent is an amide derivative of 1,3,5-benzenetrisamide, preferably 1,3,5-tris(2,2-dimethylpropanamido)benzene; The polymer composition.

11. The polymer composition of claim 10, wherein the clarifying agent is 1,2,3-trideoxy-4,5:5,7-bis-O-[(4-propylphenyl)methylene]nonitol.

12. The polymer composition according to any one of claims 1 to 4, wherein the polymer composition comprises the at least one nucleating agent.

13. The polymer composition of claim 12, wherein the nucleating agent is a phosphate ester nucleating agent.

14. 14. The polymer composition of claim 13, wherein the nucleating agent comprises 2,2'-methylenebis(4,6-di-tert-butylphenyl)phosphate (phosphate ester), and optionally a dispersant.

15. The polymer composition according to any one of claims 1 to 4, wherein the polymer composition has a melt flow index of 0.2 to 150 g / 10 min as measured by ASTM D1238 (230°C / 2.16 kg).

16. 16. The polymer composition of claim 15, wherein the polymer composition has a melt flow index of 5 to 100 g / 10 min, preferably about 20 to 30 g / 10 min, and the second polymer composition has a melt flow index of 5 to 100 g / 10 min, preferably about 25 to 35 g / 10 min.

17. 5. The polymer composition of claim 1, further comprising an additive, wherein the additive is an antioxidant, an acid neutralizer, an antistatic agent, an antiblocking agent, an antifogging agent, an anticorrosion agent, an ultraviolet absorber, a lubricant, a plasticizer, mineral oil, wax, clay, talc, calcium carbonate, diatomaceous earth, carbon black, mica, glass fiber, an extender, a slip agent, a pigment, an ultraviolet stabilizer, a flame retardant, a mold release agent, a dye, a foaming agent, a fluorescent agent, a surfactant, or any combination thereof.

18. The polymer composition according to any one of claims 1 to 4, The polymer composition has the following properties: an elongation of 1% to 20%, preferably 3% to 10%, or more preferably about 7%, as measured by ASTM D3218; and / or a melting point of 125°C to 175°C, preferably 140°C to 160°C, or more preferably about 151°C, as measured by differential scanning calorimetry (DSC); and / or The second polymer composition has the following properties: an elongation of 5% to 20%, preferably 10% to 15%, or more preferably about 12%, as measured by ASTM D638; and / or a melting point of 125°C to 200°C, preferably 150°C to 175°C, or more preferably about 165°C, as measured by differential scanning calorimetry (DSC); having at least one of The polymer composition.

19. 5. The polymer composition of any one of claims 1 to 4, wherein the polymer composition has a thickness of at least 2 mils, preferably at least 5 mils, more preferably at least 10 mils, or even more preferably from 20 mils to 300 mils, or even more preferably from 20 mils to 100 mils.

20. An article of manufacture comprising the polymer composition of any one of claims 1 to 4.

21. 21. The article of claim 20, wherein the article is an injection molded article, preferably having a thickness of between 20 mils and 100 mils.

22. 22. A method of making the article of claim 21, comprising obtaining the polymer composition of claim 1 and making the article by injection molding, blow molding, compression molding, stretch molding, rotational molding, transfer molding, sheet extrusion thermoforming, shallow draw thermoforming, deep draw thermoforming, or profile extrusion.

23. A method for producing the polymer composition of any one of claims 1 to 4, comprising the steps of: (a) Below: at least 95% by weight of said polypropylene; and a fining or nucleating agent; and obtaining a composition comprising: (b) extruding said composition to obtain the polymer composition of any one of claims 1 to 4; The method comprising:

24. 24. The method of claim 23, wherein the extrusion conditions include a temperature of 200°C to 260°C.

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