Polymer Compositions and Methods for Making Same - Patent application

Abstract

A method for making a polymer composition includes the steps of preparing a heterophasic thermoplastic polymer composition, preparing a compatibilizer, preparing a peroxide compound, and mixing and melting the heterophasic thermoplastic polymer composition, the compatibilizer, and the peroxide compound. The compatibilizer includes an ester compound formally derived from a polyol containing three or more hydroxy groups and an aliphatic carboxylic acid containing one or more carbon-carbon double bonds. The modified polymer composition includes a heterophasic thermoplastic polymer composition and a compatibilizer. The modified polymer composition has an ethylene discontinuous phase present in the form of discrete particles in a propylene continuous phase. The discrete particles of the ethylene discontinuous phase are present in the modified polymer composition at a concentration of 2.1 particles or more per cubic micron.

Description

[Technical field]

[0001]

[0001] This application is directed to polymer compositions that exhibit a desirable combination of relatively high melt flow rate and relatively high impact resistance, and methods for making such polymer compositions.

[0002]

[0002] The melt flow rate (MFR) of a polymer resin is generally a function of molecular weight. In general, increasing the melt flow rate allows the resin to be processed at low temperatures and to fill complex part geometries. Various prior art methods for increasing the melt flow rate include melt blending the resin with a compound capable of generating free radicals, such as peroxides, in an extruder. The weight average molecular weight of the polymer is reduced, and the MFR is increased. However, increasing the melt flow rate by decreasing the molecular weight of a polyolefin polymer is often found to have a detrimental effect on the strength and impact resistance of the modified polymer. For example, decreasing the molecular weight of a polymer can significantly reduce the impact resistance of the polymer. This reduced impact resistance can make the polymer unsuitable for use in certain applications or end uses. Therefore, if existing technology is utilized, a compromise must be reached between increasing the melt flow rate of the polymer and reducing the undesirable impact resistance. This compromise often means that the melt flow rate does not increase to the desired level, requiring higher processing temperatures and / or resulting in lower throughput.

[0003]

[0003] In addition, the properties of the starting polymer affect the ultimate impact resistance that can be achieved. In particular, it has been observed that polymers that appear relatively similar with respect to certain properties, e.g., ethylene content, exhibit very different impact resistance when modified in a similar manner. These performance differences appear to be the result of multiple different, but interrelated, properties of the starting polymers. Due to the unknown interactions between these properties, it has been difficult to reliably select starting polymers that can be modified to provide improved melt flow, for example, while meeting the desired level of impact resistance and providing partial or non-destructive behavior in impact tests (e.g., notched Izod and / or Charpy impact tests).

[0004]

[0004] Thus, there remains a need for additives and methods that can produce polymer compositions with increased melt flow while improving the impact resistance of the polymer so that it exhibits partial or non-destructive behavior. The methods and compositions described in this application are directed to addressing this continuing need. BRIEF SUMMARY OF THE DISCLOSURE

[0005] In a first aspect, the present invention provides a method for making a modified polymer composition, comprising the steps of: (a) providing a thermoplastic polymer; (b) providing a compatibilizer; (c) providing a peroxide compound; (d) feeding the thermoplastic polymer, the compatibilizer, and the peroxide compound to a melt mixing apparatus; and (e) processing the thermoplastic polymer, the compatibilizer, and the peroxide compound in the melt mixing apparatus at a temperature above the melting point of the thermoplastic polymer to form a polymer composition. The present invention provides a method comprising:

[0006]

[0006] In a second aspect, the present invention provides a method for making a modified polymer composition, the method comprising the steps of: (a) preparing a thermoplastic polymer; (b) preparing a compatibilizer; (c) preparing a peroxide compound; (d) combining the thermoplastic polymer, the compatibilizer, and the peroxide compound to form an intermediate composition; (e) heating the intermediate composition to a temperature above the melting point of the thermoplastic polymer; (f) mixing the intermediate composition to form a polymer composition; and (g) cooling the polymer composition to a temperature at which it solidifies.

[0007] In a third aspect, the present invention provides a modified polymer composition comprising: (a) a heterophasic thermoplastic polymer composition comprising a propylene continuous phase and an ethylene discontinuous phase; and (b) a compatibilizer.

[0008]

[0008] In a first aspect, the present invention provides a method for making a polymer composition, the method comprising the steps of: (a) preparing a thermoplastic polymer; (b) preparing a compatibilizer; (c) preparing a peroxide compound; (d) feeding the thermoplastic polymer, the compatibilizer and the peroxide compound to a melt mixing apparatus; and (e) processing the thermoplastic polymer, the compatibilizer and the peroxide compound in the melt mixing apparatus at a temperature above the melting point of the thermoplastic polymer to form the polymer composition.

[0009]

[0009] The method of the present invention can utilize any suitable thermoplastic polymer. In a preferred embodiment, the thermoplastic polymer is a polyolefin polymer. More specifically, the thermoplastic polymer is preferably a polyolefin polymer selected from the group consisting of polypropylene (e.g., polypropylene homopolymer, polypropylene copolymer, and mixtures thereof), polyethylene (e.g., high density polyethylene polymer, medium density polyethylene polymer, low density polyethylene polymer, linear low density polyethylene polymer, and mixtures thereof), and mixtures thereof.

[0010] In another preferred embodiment, the thermoplastic polymer is a heterophasic thermoplastic polymer composition comprising a continuous phase and a discontinuous phase, such as a polypropylene impact copolymer. Preferably, the continuous phase is a propylene polymer phase and the discontinuous phase is an ethylene polymer phase. In a preferred embodiment, the continuous phase is a polypropylene homopolymer, as well as a mixture of propylene and up to 50 wt % ethylene and C4-C 10 The continuous phase is preferably from about 5 to about 95 wt% (e.g., from about 5 to about 90 wt%, from about 5 to about 85 wt%, or from about 5 to about 80 wt%) of the total weight of the heterophasic thermoplastic polymer composition.

[0011] In another preferred embodiment, the discontinuous phase is an ethylene homopolymer, as well as a mixture of ethylene and a C3-C 10 The ethylene content of the discontinuous phase is preferably about 8 wt% or more. More preferably, the ethylene content of the discontinuous phase is about 8 wt% to about 90 wt% (e.g., about 8 wt% to about 80 wt%). In another preferred embodiment, the ethylene content of the heterophasic thermoplastic polymer composition is about 5 wt% to about 30 wt%.

[0012] In a particularly preferred embodiment, the continuous phase is a polypropylene homopolymer, as described above, and a mixture of propylene and up to 50 wt. % ethylene and C4-C 10 The discontinuous phase is selected from the group consisting of ethylene homopolymers, as well as copolymers of ethylene and one or more comonomers selected from the group consisting of α-olefin monomers, as described above. 10 More preferably, the discontinuous phase is a copolymer of ethylene and propylene.

[0013]

[0013] An example of a heterophasic thermoplastic polymer composition that can be modified is an impact copolymer characterized by a relatively rigid polypropylene homopolymer matrix (continuous phase) and a finely dispersed phase of ethylene-propylene rubber (EPR) particles. Polypropylene impact copolymers can be made in a two-stage process, where the polypropylene homopolymer is polymerized first and the ethylene-propylene rubber is polymerized in a second stage. Alternatively, the impact copolymers can be made in three or more stages, which are known in the art. Suitable methods can be found in the following references: US 5,639,822 and US 7,649,052 B2. Examples of suitable methods for making polypropylene impact copolymers are Spheripol®, Unipol®, Mitsui process, Novolen process, Spherizone®, Catalloy®, Chisso process, Innovene®, Borstar®, Mitsubishi Horizone process, and Sinopec process. These processes can use heterogeneous or homogeneous Ziegler-Natta metallocene catalysts to catalyze the polymerization reaction.

[0014]

[0014] A heterophasic thermoplastic polymer composition can be formed by melt mixing two or more polymer compositions to form at least two distinct phases in the solid state. As an example, a heterophasic thermoplastic polymer composition may include three distinct phases. A heterophasic thermoplastic polymer composition may result from melt mixing two or more types of recycled polyolefin compositions. Thus, the process of providing a "heterophasic thermoplastic polymer" described herein includes utilizing a polymer composition that is already heterophasic in the process, and melt mixing two or more polymer compositions during the process, where the two or more polymer compositions form a heterophasic thermoplastic polymer. For example, a heterophasic thermoplastic polymer composition can be made by melt mixing a polypropylene homopolymer and an ethylene / α-olefin copolymer, such as an ethylene / butadiene elastomer. Examples of suitable copolymers are Engage™, Exact™, Vistamaxx™, Versify™, INFUSE™, Nordel™, Vistalon™, Exxelor™, and Affinity™. It is further understood that the miscibility of the polyolefin polymer components forming the heterophasic thermoplastic polymer composition may vary when the composition is heated above the melting point of the continuous phase of the system, and the system still forms two or more phases upon cooling and solidifying. Examples of heterophasic thermoplastic polymers can be found in US8,207,272B2 and EP1391482B1.

[0015] In one embodiment of the present invention, the heterophasic thermoplastic polymer composition used in the present process does not have any polyolefin component with unsaturated bonds. In particular, the heterophasic thermoplastic polymer composition contains a propylene polymer phase and an ethylene polymer phase, and both the propylene polymer in the propylene polymer phase and the ethylene polymer in the ethylene polymer phase do not contain unsaturated bonds.

[0016] In another embodiment of these embodiments utilizing a heterophasic thermoplastic polymer composition, in addition to the propylene polymer and ethylene polymer components, the heterophasic thermoplastic polymer composition may include elastomers, such as elastomeric ethylene copolymers, elastomeric propylene copolymers, styrene block copolymers, such as styrene-butadiene-styrene (SBS), styrene-ethylene-butylene-styrene (SEBS), styrene-ethylene-propylene-styrene (SEPS), and styrene-isoprene-styrene (SIS), plastomers, ethylene-propylene-diene terpolymers, LLDPE, LDPE, VLDPE, polybutadiene, polyisoprene, natural rubber, and amorphous polyolefins. The rubber may be virgin or reclaimed.

[0017] As shown above, it has been observed that heterophasic thermoplastic polymer compositions that appear similar in many aspects (e.g. impact copolymers with similar monomer content) exhibit very different impact behavior when modified with peroxides and compatibilizers according to the disclosed method. After extensive experimentation and research, the inventors have found that the ultimate impact strength that can be achieved is determined by three properties of the heterophasic thermoplastic polymer composition: (i) the melt flow rate; (ii) the soluble fraction, and (iii) the ethylene content of the soluble fraction. The melt flow rate is expressed in g / 10 min and is preferably measured according to ASTM D1238 or ISO 1133 at 230° C. and a load of 2.16 kg for polypropylene. The soluble fraction is the portion of both the continuous and discontinuous phase that is soluble in the selected solvent. The soluble fraction (expressed as a weight percentage (wt%) of the polymer composition) and the ethylene content of the soluble fraction (also expressed as a weight percentage (wt%)) are preferably measured using a Crystex® 42 analyzer (Polymer Char, Valencia, Spain) and 1,2,4-trichlorobenzene stabilized with 300 ppm of pentaerythritol tetrakis (3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate). The complete set of test parameters preferably used to analyze heterophasic thermoplastic polymer compositions using the Crystex® 42 analyzer is described below in the discussion preceding the examples. In addition to the soluble fraction and the ethylene content of the soluble fraction, the Crystex® 42 analyzer can also measure the intrinsic viscosity of the soluble and crystalline fractions, the ratio of which (i.e., the intrinsic viscosity of the soluble fraction divided by the intrinsic viscosity of the crystalline fraction) is known as the “β / α” value.

[0018]

[0018] The heterophasic thermoplastic polymer composition has a melt flow rate (MFR), a soluble fraction (SF), and an ethylene content (C2 SF) preferably having: (1) 0<(-0.29×MFR)+(1.269×SF)-(0.626×C2 SF )+5.9. More preferably, MFR, SF, and C2 SF satisfies the following inequality: (1a)0<(-0.29×MFR)+(1.269×SF)-(0.626×C2 SF )+5.0. Even more preferably, MFR, SF, and C2 SF satisfies the following inequality: (1b)0<(-0.29×MFR)+(1.269×SF)-(0.626×C2 SF )+4.1.

[0019] In an alternative preferred embodiment, the heterophasic thermoplastic polymer composition has a melt flow rate (MFR), a soluble fraction (SF), and a soluble fraction (C2 SF ) preferably has an ethylene content of: (2) 0<(1.61×SF)+11.1-C2 SF ; and (3) 0<(3.66×SF)-54.3-MFR. More preferably, MFR, SF, and C2 SF satisfies both of the following inequalities: (4) 0≦(1.61×SF)+9.6-C2 SF ; and (5) 0≦(3.66×SF)-59.7-MFR Even more preferably, MFR, SF, and C2 SF satisfies both of the following inequalities: (6) 0≦(1.61×SF)+8.1-C2 SF ; and (7) 0≦(3.66×SF)−67.1−MFR.

[0020]

[0020] Heterophasic thermoplastic polymer compositions (hereinafter sometimes referred to as "responsive resins") having melt flow rates, soluble fractions, and ethylene content of the soluble fractions that satisfy one or more of the aforementioned sets of inequalities have been shown to exhibit a particularly desirable combination of high melt flow rates and high impact strength when modified according to the methods described herein. For example, responsive resins that exhibit relatively high impact resistance (e.g., partial or non-destructive behavior) prior to modification can be modified via the disclosed methods to dramatically increase their melt flow rates while maintaining the same degree of impact resistance. Alternatively, the impact resistance of such polymer compositions can be increased such that the material exhibits partial or non-destructive failure in both Izod and Charpy impact tests relative to responsive resins that do not exhibit high impact resistance prior to modification. These results are particularly surprising in view of the fact that these improvements in impact resistance are accompanied by a significant increase in the melt flow rate of the responsive resins. As explained above, an increase in the melt flow rate of a polymer composition typically results in a decrease in its impact resistance. Such partial or non-destructive failure behavior is particularly desirable in the industry because it demonstrates a high degree of impact resistance, meaning that articles made from the modified polymer composition are suitable for a wide variety of end uses.

[0021] The melt flow rate of the heterophasic thermoplastic polymer composition is preferably about 1 g / 10 min or more. The melt flow rate of the heterophasic thermoplastic polymer composition is preferably about 50 g / 10 min or less. More preferably, the melt flow rate of the heterophasic thermoplastic polymer composition is about 40 g / 10 min or less, about 35 g / 10 min or less, or about 30 g / 10 min or less. Thus, in a series of preferred embodiments, the melt flow rate of the heterophasic thermoplastic polymer composition is about 1 to about 50 g / 10 min or about 1 to about 40 g / 10 min (e.g., about 5 to about 40 g / 10 min, about 8 to about 40 g / 10 min, about 8 to about 35 g / 10 min, or about 8 to about 30 g / 10 min).

[0022] The heterophasic thermoplastic polymer composition preferably has a soluble fraction of about 5 wt% or more. More preferably, the heterophasic thermoplastic polymer composition has a soluble fraction of about 10 wt% or more, about 11 wt% or more, about 12 wt% or more, about 13 wt% or more, about 14 wt% or more, about 15 wt% or more, about 16 wt% or more, about 17 wt% or more, or about 18 wt% or more. The heterophasic thermoplastic polymer composition preferably has a soluble fraction of about 50 wt% or less, about 40 wt% or less, about 35 wt% or less, about 30 wt% or less, or about 35 wt% or less. Thus, in a series of preferred embodiments, the heterophasic thermoplastic polymer composition has a soluble fraction of about 5 to about 50 wt% (e.g., about 5 to about 40 wt%, about 5 to about 35 wt%, about 5 to about 30 wt%, or about 5 to about 25 wt%), about 10 to about 50 wt% (e.g., about 10 to about 40 wt%, about 10 to about 35 wt%, about 10 to about 30 wt%, or about 10 to about 25 wt%), about 12 to about 50 wt% (e.g., about 12 to about 40 wt%, about 12 to about 35 wt%, about 12 to about 30 wt%, or about 12 to about 25 wt%), about 15 to about 50 wt% (e.g., about 15 to about 40 wt%, about 15 to about 35 wt%, about 15 to about 30 wt%, or about 15 to about 25 wt%), about 16 to about 50 wt% (e.g., about 16 to about 40 wt%, about 16 to about 35 wt%, about 16 to about 30 wt%, or about 16 to about 25 wt%), about 17 to about 50 wt% (e.g., about 17 to about 40 wt%, about 17 to about 35 wt%, about 17 to about 30 wt%, or about 17 to about 25 wt%), or about 18 to about 50 wt% (e.g., about 18 to about 40 wt%, about 18 to about 35 wt%, about 18 to about 30 wt%, or about 18 to about 25 wt%).

[0023]

[0023] The ethylene content of the soluble fraction of the heterophasic thermoplastic polymer composition (C2 SF ) is preferably about 8 wt% or more. More preferably, the ethylene content of the soluble fraction is about 10 wt% or more, about 15 wt% or more, about 20 wt% or more, about 25 wt% or more, or about 30 wt% or more. The ethylene content of the soluble fraction of the heterophasic thermoplastic polymer composition (C2 SF) is preferably about 90 wt% or less. More preferably, the ethylene content of the soluble fraction is about 85 wt% or less, about 80 wt% or less, about 75 wt% or less, about 70 wt% or less, about 65 wt% or less, about 60 wt% or less, about 55 wt% or less, or about 50 wt% or less. Thus, in a series of preferred embodiments, the ethylene content (C2 SF ) is about 8 to about 90 wt% (e.g., about 8 to about 85 wt%, about 8 to about 80 wt%, about 8 to about 75 wt%, about 8 to about 70 wt%, about 8 to about 65 wt%, about 8 to about 60 wt%, about 8 to about 55 wt%, or about 8 to about 50 wt%), about 10 to about 90 wt% (e.g., about 10 to about 85 wt%, about 10 to about 80 wt%, about 10 to about 75 wt%, about 10 to about 70 wt%, about 10 to about 65 wt%, about 10 to about 60 wt%, about 10 to about 55 wt%, or about 10 to about 50 wt%), about 15 to about 90 wt% (for example, about 15 to about 85 wt%, about 15 to about 80 wt%, about 15 to about 75 wt%, about 15 to about 70 wt%, about 15 to about 65 wt%, about 15 to about 60 wt%, about 15 to about 55 wt%, or about 15 to about 50 wt%), about 20 to about 9 0 wt% (for example, about 20 to about 85 wt%, about 20 to about 80 wt%, about 20 to about 75 wt%, about 20 to about 70 wt%, about 20 to about 65 wt%, about 20 to about 60 wt%, about 20 to about 55 wt%, or about 20 to about 50 wt%), about 25 to about 90 wt% (for example, about 25 to about 85 wt%, about 25 to about 80 wt%, about 25 to about 75 wt%, about 25 to about 70 wt%, about 25 to about 65 wt%, about 25 to about 60 wt%, about 25 to about 55 wt%, or about 25 to about 50 wt%, or about 30 to about 90 wt% (e.g., about 30 to about 85 wt%, about 30 to about 80 wt%, about 30 to about 75 wt%, about 30 to about 70 wt%, about 30 to about 65 wt%, about 30 to about 60 wt%, about 30 to about 55 wt%, or about 30 to about 50 wt%).

[0024] Other characteristics of the bulk (measured before treatment with the compatibilizer) may also affect the physical property improvements (e.g., increased impact strength) realized through the incorporation of the compatibilizer described herein. In particular, with respect to the bulkiness of the heterophasic thermoplastic polymer composition, ethylene preferably comprises about 6 wt% or more, about 7 wt% or more, about 8 wt% or more, or about 9 wt% or more of the total weight of the heterophasic thermoplastic polymer composition. Furthermore, about 5 mol% or more, about 7 mol% or more, about 8 mol% or more, or about 9 mol% or more of the ethylene present in the heterophasic thermoplastic polymer composition is preferably present in ethylene triads (i.e., groups of three ethylene monomer units linked in succession). Finally, the number average sequence length of the ethylene runs (ethylene monomer units linked in succession) in the heterophasic thermoplastic polymer composition is preferably about 3 or more, about 3.25 or more, about 3.5 or more, about 3.75 or more, or about 4 or more. Both the mole% of ethylene in ethylene triads and the number average sequence length of the ethylene runs can be calculated using methods known in the art. 13 The heterophasic thermoplastic polymer composition can be measured using C nuclear magnetic resonance (NMR) techniques. The heterophasic thermoplastic polymer composition can exhibit any of the characteristics described in this paragraph. Preferably, the heterophasic thermoplastic polymer composition can exhibit two or more of the characteristics described in this paragraph. More preferably, the heterophasic thermoplastic polymer composition can exhibit all of the characteristics described in this paragraph.

[0025]

[0025] Certain characteristics of the ethylene phase of the heterophasic thermoplastic polymer composition (measured prior to treatment with the compatibilizer) may also influence the improvement in physical properties (e.g., increased impact strength) realized through the incorporation of the compatibilizer. The characteristics of the ethylene phase of the composition may be determined by any suitable technique, for example, by temperature rising elution fractionation (TREF) or fractionation of the resulting fractions. 13It can be measured using C NMR analysis. In a preferred embodiment, about 30 mol % or more, about 40 mol % or more, or about 50 mol % or more of the ethylene present in the 60 ° C TREF fraction of the heterophasic thermoplastic polymer composition is present in ethylene triads. In another preferred embodiment, about 30 mol % or more, about 40 mol % or more, or about 50 mol % or more of the ethylene present in the 80 ° C TREF fraction of the heterophasic thermoplastic polymer composition is present in ethylene triads. In another preferred embodiment, about 5 mol % or more, about 10 mol % or more, about 15 mol % or more, or about 20 mol % or more of the ethylene present in the 100 ° C TREF fraction of the heterophasic thermoplastic polymer composition is present in ethylene triads. The number average sequence length of the ethylene runs present in the 60 ° C TREF fraction of the heterophasic thermoplastic polymer composition is preferably about 3 or more, about 4 or more, about 5 or more, or about 6 or more. The number average sequence length of the ethylene runs present in the 80° C. TREF fraction of the heterophasic thermoplastic polymer composition is preferably about 7 or more, about 8 or more, about 9 or more, or about 10 or more. The number average sequence length of the ethylene runs present in the 100° C. TREF fraction of the heterophasic thermoplastic polymer composition is preferably about 10 or more, about 12 or more, about 15 or more, or about 16 or more. The heterophasic thermoplastic polymer composition can exhibit any one of the characteristics of the TREF fraction described above, or any suitable combination of the characteristics of the TREF fraction described above. In a preferred embodiment, the heterophasic thermoplastic polymer composition exhibits all of the characteristics of the TREF fraction described above (i.e., the ethylene triad and number average sequence length characteristics in the 60° C., 80° C., and 100° C. TREF fractions described above).

[0026]

[0026] Heterophasic thermoplastic polymer compositions exhibiting the characteristics described in the preceding paragraph have been observed to respond more favorably to the addition of a compatibilizer than heterophasic thermoplastic polymer compositions not exhibiting these characteristics. In particular, heterophasic thermoplastic polymer compositions exhibiting these characteristics, when processed by the method of the present invention, show significant improvements in impact strength and partial or non-destructive behavior, whereas heterophasic thermoplastic polymer compositions not exhibiting these characteristics do not show these significant improvements when processed under the same conditions. This difference in response and performance has been observed even when the different polymer compositions have approximately the same total ethylene content (i.e., the percentage of ethylene in each polymer composition is approximately the same). This result was surprising and unexpected.

[0027] The compatibilizer utilized in the present method preferably comprises an ester compound formally derived from a polyol containing three or more hydroxy groups and an aliphatic carboxylic acid containing one or more carbon-carbon double bonds. As used herein, the term "formally derived" is used in the same sense as the definition of "ester" in IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"), compiled by AD McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997). Thus, the ester compound need not be prepared by direct reaction of a polyol with an aliphatic carboxylic acid. Rather, the ester compound can be prepared by reaction of a polyol or a derivative thereof (e.g., an alkyl halide derivative of a polyol, or a methanesulfonyl, p-toluenesulfonyl or trifluoromethylsulfonyl ester of a polyol) with an aliphatic carboxylic acid or a derivative thereof (e.g., an acid salt, an acid halide derivative of an aliphatic carboxylic acid, or an active ester derivative, e.g., an ester with nitrophenol, N-hydroxysuccinimide or hydroxybenzotriazole). The ester compound is preferably formally derived by linking each of the hydroxy groups of the polyol with an aliphatic carboxylic acid. The polyol from which the ester compound is formally derived can be any suitable polyol containing three or more hydroxy groups, such as glycerol, 2-(hydroxymethyl)-2-ethylpropane-1,3-diol, erythritol, threitol, arabitol, xylitol, ribitol, mannitol, sorbitol, galactitol, fucitol, iditol, inositol, volemitol, pentaerythritol and mixtures thereof. In a preferred embodiment, the polyol is 2-(hydroxymethyl)-2-ethylpropane-1,3-diol.

[0028] The aliphatic carboxylic acid from which the ester compound is formally derived may be any suitable aliphatic carboxylic acid containing one or more carbon-carbon double bonds, for example, acrylic acid. Preferably, the aliphatic carboxylic acid is selected from the group consisting of C4 or higher aliphatic carboxylic acids. More preferably, the aliphatic carboxylic acid is selected from the group consisting of C4 to C 18 Aliphatic carboxylic acids (e.g., C4-C 16 Even more preferably, the aliphatic carboxylic acid is selected from the group consisting of C4 to C 10 The ester compound is selected from the group consisting of aliphatic carboxylic acids. In a preferred embodiment, the aliphatic carboxylic acid contains two or more carbon-carbon double bonds. In such an embodiment, at least two of the carbon-carbon double bonds in the aliphatic carboxylic acid are preferably conjugated. In a preferred embodiment, the aliphatic carboxylic acid is 2,4-hexadienoic acid. Thus, in a preferred embodiment, the ester compound is 2,2-bis[(1,3-pentadienylcarbonyloxy)methyl]butyl 2,4-hexadienoate, which can be formally derived from one equivalent of 2-(hydroxymethyl)-2-ethylpropane-1,3-diol and three equivalents of 2,4-hexanedienoic acid.

[0029] Any suitable peroxide compound can be used in the above described method. Suitable peroxide compounds include 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexyne-3,3,6,6,9,9-pentamethyl-3-(ethyl acetate)-1,2,4,5-tetraoxycyclononane, tert-butyl hydroperoxide, hydrogen peroxide, dicumyl peroxide, tert-butylperoxyisopropyl carbonate, di-tert-butyl peroxide, p-chlorobenzoyl peroxide, di ... tert-Butyl diperoxide, tert-butyl cumyl peroxide; tert-butyl hydroxyethyl peroxide, di-tert-amyl peroxide and 2,5-dimethylhexene-2,5-diperisononanoate, acetylcyclohexanesulfonyl peroxide, diisopropyl peroxydicarbonate, tert-amyl perneodecanoate, tert-butyl perneodecanoate, tert-butyl perpivalate, tert-amyl perpivalate, bis(2,4-dichlorobenzoyl) peroxide oxide, diisononanoyl peroxide, didecanoyl peroxide, dioctanoyl peroxide, dilauroyl peroxide, bis(2-methylbenzoyl) peroxide, disuccinoyl peroxide, diacetyl peroxide, dibenzoyl peroxide, tert-butyl per-2-ethylhexanoate, bis(4-chlorobenzoyl) peroxide, tert-butyl perisobutyrate, tert-butyl permaleate, 1,1-bis(tert-butylperoxy)-3,5,5-trimethylsilyl Cyclohexane, 1,1-bis(tert-butylperoxy)cyclohexane, tert-butylperoxyisopropyl carbonate, tert-butyl perisononanoate, 2,5-dimethylhexane 2,5-dibenzoate, tert-butyl peracetate, tert-amyl perbenzoate, tert-butyl perbenzoate, 2,2-bis(tert-butylperoxy)butane, 2,2-bis(tert-butylperoxy)propane, dicumyl peroxide, 2,5-dimethylhexane 2,The peroxide compound may include, but is not limited to, 5-di-tert-butyl peroxide, 3-tert-butylperoxy-3-phenylphthalide, di-tert-amyl peroxide, α,α'-bis(tert-butylperoxyisopropyl)benzene, 3,5-bis(tert-butylperoxy)-3,5-dimethyl-1,2-dioxolane, di-tert-butyl peroxide, 2,5-dimethylhexyne 2,5-di-tert-butyl peroxide, 3,3,6,6,9,9-hexamethyl-1,2,4,5-tetraoxacyclononane, p-menthane hydroperoxide, pinane hydroperoxide, diisopropylbenzene mono-α-hydroperoxide, cumene hydroperoxide, or tert-butyl hydroperoxide. In a preferred embodiment, the peroxide compound is 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane.

[0030] In the method, the thermoplastic polymer, the compatibilizer, and the peroxide compound are fed to a melt mixing device. The melt mixing device can be any suitable device capable of heating the thermoplastic polymer to a temperature at which it melts and mixing the thermoplastic polymer, the compatibilizer, and the peroxide compound while the polymer is molten. The thermoplastic polymer, the compatibilizer, and the peroxide compound can be mixed before heating, or the thermoplastic polymer can be heated to a desired temperature, followed by the addition of the compatibilizer and the peroxide compound. Alternatively, the thermoplastic polymer and the compatibilizer can be combined and then heated, followed by the addition of the peroxide compound (e.g., once the mixture is heated to a temperature above the melting point of the polymer). Suitable melt mixing devices include, but are not limited to, extruders, reciprocating screw injection molding machines, and high shear mixers. In a preferred embodiment of the first method, the melt mixing device is an extruder. Thus, in an embodiment where the melt mixing device is an extruder, the method includes feeding the thermoplastic polymer, the compatibilizer, and the peroxide compound to the extruder, and passing the thermoplastic polymer, the compatibilizer, and the peroxide compound through the extruder at a temperature above the melting point of the thermoplastic polymer, thereby forming a polymer composition. When an extruder is used, the thermoplastic polymer, the compatibilizer, and the peroxide compound can be fed simultaneously to the main inlet or hopper of the extruder. Alternatively, the thermoplastic polymer can be fed to the main inlet or hopper of the extruder, and the compatibilizer and the peroxide compound can be introduced to the extruder via one or more side feeders. In another alternative, the thermoplastic polymer and the compatibilizer can be fed to the main inlet or hopper of the extruder, and the peroxide compound can be introduced to the extruder via a side feeder.

[0031] The compatibilizer and the peroxide compound can be fed to the melt mixing device in any suitable amount. Preferably, the compatibilizer is fed to the melt mixing device in an amount that results in an initial concentration of the ester compound of about 200 to about 15,000 ppm based on the combined weight of the thermoplastic polymer, the compatibilizer, and the peroxide compound. More preferably, the compatibilizer is fed to the melt mixing device in an amount that results in an initial concentration of the ester compound of about 200 to about 10,000 pp (e.g., about 200 to about 8,000 ppm, about 200 to about 6,000 ppm, or about 200 to about 5,000 ppm) based on the combined weight of the thermoplastic polymer, the compatibilizer, and the peroxide compound.

[0032]

[0032] Preferably, the peroxide compound is provided to the melt mixing device in an amount that provides an initial concentration of active oxygen of about 10 to about 315 ppm based on the combined weight of the thermoplastic polymer, the compatibilizer, and the peroxide compound. More preferably, the peroxide compound is provided to the melt mixing device in an amount that provides an initial concentration of active oxygen of about 50 to about 315 ppm based on the combined weight of the thermoplastic polymer, the compatibilizer, and the peroxide compound. Even more preferably, the peroxide compound is provided to the melt mixing device in an amount that provides an initial concentration of active oxygen of about 50 to about 265 ppm based on the combined weight of the thermoplastic polymer, the compatibilizer, and the peroxide compound. Most preferably, the peroxide compound is provided to the melt mixing device in an amount that provides an initial concentration of active oxygen of about 50 to about 215 ppm based on the combined weight of the thermoplastic polymer, the compatibilizer, and the peroxide compound. The amount of active oxygen provided by a given amount of peroxide compound can be calculated using the following equation:

[0033]

number

[0034] In the equation, n is the number of peroxide groups in the peroxide compound, P is the purity of the peroxide compound, C is the concentration (ppm) of the peroxide compound added to the system, and M is the molar mass of the peroxide compound. Thus, when 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane with a purity of 95% is added at an initial concentration of 500 ppm, the peroxide compound will result in an initial concentration of active oxygen of 52.5 ppm.

[0035] As indicated above, the thermoplastic polymer, the compatibilizer, and the peroxide compound are processed in a melt mixing device at a temperature above the melting point of the thermoplastic polymer. In those embodiments where the thermoplastic polymer is a heterophasic thermoplastic polymer, the components are heated to a temperature above the melting point of the continuous phase of the heterophasic thermoplastic polymer. By way of example, the components are preferably melt mixed at a temperature of about 160°C to about 300°C. In those embodiments where the thermoplastic polymer is a propylene impact copolymer, the components are preferably melt mixed at a temperature of about 180°C to about 290°C.

[0036]

[0034] In a second aspect, the present invention provides a method for making a polymer composition comprising the steps of: (a) preparing a thermoplastic polymer; (b) preparing a compatibilizer; (c) preparing a peroxide compound; (d) combining the thermoplastic polymer, the compatibilizer and the peroxide compound to form an intermediate composition; (e) heating the intermediate composition to a temperature above the melting point of the thermoplastic polymer; (f) mixing the intermediate composition to form the polymer composition; and (g) cooling the polymer composition to a temperature at which it solidifies.

[0037]

[0035] The thermoplastic polymers, compatibilizers, and peroxide compounds used in this second method embodiment may be any of the thermoplastic polymers, compatibilizers, and peroxide compounds discussed above in connection with the first method embodiment of the present invention, including the preferred thermoplastic polymers, compatibilizers, and peroxide compounds identified in connection with the first method embodiment.

[0038]

[0036] In this second method embodiment, any suitable amount of compatibilizer can be used. Preferably, the compatibilizer is combined with the thermoplastic polymer and the peroxide compound in an amount to provide about 200 to about 15,000 ppm of the ester compound in the intermediate composition. More preferably, the compatibilizer is combined with the thermoplastic polymer and the peroxide compound in an amount to provide about 200 to about 10,000 ppm (e.g., about 200 to about 8,000 ppm, about 200 to about 6,000 ppm, or about 200 to about 5,000 ppm) of the ester compound in the intermediate composition.

[0039] Any suitable amount of peroxide compound can be used in this second process embodiment. Preferably, the peroxide compound is combined with the thermoplastic polymer and the compatibilizer in an amount to provide from about 10 to about 315 ppm of active oxygen in the intermediate composition. More preferably, the peroxide compound is combined with the thermoplastic polymer and the compatibilizer in an amount to provide from about 50 to about 315 ppm of active oxygen in the intermediate composition. Even more preferably, the peroxide compound is combined with the thermoplastic polymer and the compatibilizer in an amount to provide from about 50 to about 265 ppm of active oxygen in the intermediate composition. Most preferably, the peroxide compound is combined with the thermoplastic polymer and the compatibilizer in an amount to provide from about 50 to about 215 ppm of active oxygen in the intermediate composition.

[0040] The second method embodiment differs from the first in that the thermoplastic polymer, the compatibilizer, and the peroxide compound are combined before being heated. This method can be utilized in processes where the components are dry blended prior to melt processing, such as certain compression molding processes. As in the first method embodiment, the components are heated to a temperature above the melting point of the thermoplastic polymer. In an embodiment where the thermoplastic polymer is a heterophasic thermoplastic polymer, the components are heated to a temperature above the melting point of the continuous phase of the heterophasic thermoplastic polymer. By way of example, the components are preferably heated to a temperature of about 160°C to about 300°C. In an embodiment where the thermoplastic polymer is a propylene impact copolymer, the components are preferably heated to a temperature of about 180°C to about 290°C.

[0041]

[0039] Without being bound to any particular theory, it is believed that the method described above improves the physical properties of thermoplastic polymers by linking polymer chains within the polymer matrix. In particular, when the thermoplastic polymer is a heterophasic thermoplastic polymer, it is believed that the method creates bonds between the propylene polymer in the continuous phase and the ethylene polymer in the discontinuous phase. It is believed that these bonds are created when the peroxide compound breaks the polymer chains in the polymer, and this polymer chain scission results in an increase in the MFR of the polymer. Furthermore, it is believed that these broken polymer chains have carbon-centered free radicals that can react with one of the carbon-carbon double bonds in the ester compound to generate a new carbon-carbon double bond between the polymer chain and the ester compound. As this series of polymer chain scission and free radical addition to the ester compound proceeds, it is believed that at least a portion of the ester compound in the polymer reacts to provide crosslinks or links between different polymers (e.g., propylene polymer and ethylene polymer) in the heterophasic polymer.

[0042] The methods described above can be used to produce polymer compositions that are then finalized using any conventional polymer processing technique, such as injection molding, thin-wall injection molding, single-screw compounding, twin-screw compounding, Banbury mixing, co-mixer mixing, two-roll compounding, sheet extrusion, fiber extrusion, film extrusion, pipe extrusion, profile extrusion, extrusion coating, extrusion blow molding, injection blow molding, injection stretch blow molding, compression molding, extrusion compression molding, compression blow molding, compression stretch blow molding, thermoforming, and rotational molding. Thermoplastic polymer articles made using the polymer compositions formed by these methods can be constructed of multiple layers, one or any suitable number of the multiple layers containing the polymer composition formed by these methods. By way of example, typical end-use products include containers, packaging, automotive parts, bottles, expanded or foamed articles, appliance parts, closures, cups, furniture, household goods, battery cases, crates, pallets, films, sheets, fibers, pipes, and rotational molded articles.

[0043] In embodiments of the method described above, the compatibilizer can be provided in the form of a masterbatch composition, for example, a masterbatch composition comprising (a) a thermoplastic binder, (b) an ester compound described above, and (c) optionally, a peroxide compound. In practicing the method, the masterbatch composition can be combined with a thermoplastic polymer (e.g., a heterophasic polypropylene impact copolymer) in amounts that provide a desired initial concentration of both the peroxide compound and, if present, the ester compound.

[0044]

[0042] The thermoplastic binder in the masterbatch composition can be any thermoplastic material capable of binding together the components of the masterbatch composition. The thermoplastic binder preferably has a melting point of about 140°C or less, about 130°C or less, about 120°C or less, more preferably about 110°C or less, about 100°C or less, about 90°C or less, about 80°C or less, about 70°C or less, about 60°C or less, or about 50°C or less. Suitable thermoplastic binders include, but are not limited to, polypropylene, polypropylene wax, low density polyethylene, polyethylene wax, propylene / ethylene copolymers (e.g., those sold under the name "Vistamaxx" by ExxonMobil Chemical), ethylene vinyl acetate copolymers, and mixtures thereof.

[0045]

[0043] The peroxide and ester compounds in the masterbatch composition may be any of the peroxide and ester compounds discussed above in connection with the first process embodiment of the present invention, including the preferred peroxide and ester compounds identified in connection with the first process embodiment. Thus, in a preferred embodiment, the ester compound is 2,2-bis[(1,3-pentadienylcarbonyloxy)methyl]butyl 2,4-hexadienoate. In another preferred embodiment, the peroxide compound is 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane. Finally, in a particularly preferred embodiment of the masterbatch composition, the ester compound is 2,2-bis[(1,3-pentadienylcarbonyloxy)methyl]butyl 2,4-hexadienoate and the peroxide compound is 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane.

[0046]

[0044] The ester compound can be present in the master batch composition in any suitable amount. Preferably, the ester compound is present in the master batch composition in an amount of about 1 wt% or more based on the total weight of the master batch composition. More preferably, the ester compound is present in the master batch composition in an amount of about 2 wt% or more, about 3 wt% or more, about 4 wt% or more, about 5 wt% or more, about 6 wt% or more, about 7 wt% or more, about 8 wt% or more, about 9 wt% or more, or about 10 wt% or more based on the total weight of the master batch composition. Preferably, the ester compound is present in the master batch composition in an amount of about 40 wt% or less based on the total weight of the master batch composition. Thus, in a series of preferred embodiments, the ester compound is present in the masterbatch composition in an amount of from about 1 wt % to about 40 wt %, from about 2 wt % to about 40 wt %, from about 3 wt % to about 40 wt %, from about 4 wt % to about 40 wt %, from about 5 wt % to about 40 wt %, from about 6 wt % to about 40 wt %, from about 7 wt % to about 40 wt %, from about 8 wt % to about 40 wt %, from about 9 wt % to about 40 wt %, or from about 10 wt % to about 40 wt %, based on the total weight of the masterbatch composition.

[0047]

[0045] When present, the peroxide compound can be present in the master batch composition in any suitable amount. Preferably, the peroxide compound is present in the master batch composition in an amount of about 1 wt% or more, based on the total weight of the master batch composition. More preferably, the peroxide compound is present in the master batch composition in an amount of about 2 wt% or more, about 3 wt% or more, about 4 wt% or more, about 5 wt% or more, about 6 wt% or more, about 7 wt% or more, about 8 wt% or more, about 9 wt% or more, or about 10 wt% or more, based on the total weight of the master batch composition. Preferably, the peroxide compound is present in the master batch composition in an amount of about 40 wt% or less, based on the total weight of the master batch composition. Thus, in a series of preferred embodiments, the peroxide compound is present in the masterbatch composition in an amount of from about 1 wt % to about 40 wt %, from about 2 wt % to about 40 wt %, from about 3 wt % to about 40 wt %, from about 4 wt % to about 40 wt %, from about 5 wt % to about 40 wt %, from about 6 wt % to about 40 wt %, from about 7 wt % to about 40 wt %, from about 8 wt % to about 40 wt %, from about 9 wt % to about 40 wt %, or from about 10 wt % to about 40 wt %, based on the total weight of the masterbatch composition.

[0048] The masterbatch composition may contain other polymeric additives in addition to the ester compound and the optional peroxide compound. Suitable additional polymer additives include, but are not limited to, antioxidants (e.g., phenolic antioxidants, phosphite antioxidants, and combinations thereof), antiblocking agents (e.g., amorphous silica and diatomaceous earth), pigments (e.g., organic and inorganic pigments) and other colorants (e.g., dyes and polymeric colorants), fillers and reinforcing agents (e.g., glass, fiberglass, talc, calcium carbonate, and magnesium oxysulfate whiskers), nucleating agents, clarifying agents, acid scavengers (e.g., metal salts of fatty acids, such as metal salts of stearic acid and dihydrotalcite), polymer processing additives (e.g., fluoropolymer polymer processing additives), polymer crosslinkers, slip agents (e.g., fatty acid amide compounds derived from the reaction of fatty acids with ammonia or with amine-containing compounds), fatty acid ester compounds (e.g., fatty acid ester compounds derived from the reaction of fatty acids with hydroxyl-containing compounds, such as glycerol, diglycerol, and combinations thereof), and combinations of the foregoing.

[0049] As indicated above, the masterbatch composition may contain nucleating agents and / or clarifiers in addition to the other components described above. Suitable nucleating agents include benzoates (e.g., sodium benzoate and aluminum 4-tert-butylbenzoate), 2,2'-methylene-bis-(4,6-di-tert-butylphenyl)phosphates (e.g., sodium 2,2'-methylene-bis-(4,6-di-tert-butylphenyl)phosphate or aluminum 2,2'-methylene-bis-(4,6-di-tert-butylphenyl)phosphate), bicyclo[2.2.1]heptane-2,3-dicarboxylates (e.g., bicyclo[2 Suitable fining agents include, but are not limited to, disodium bicyclo[2.2.1]heptane-2,3-dicarboxylate or calcium bicyclo[2.2.1]heptane-2,3-dicarboxylate), cyclohexane-1,2-dicarboxylates (e.g., calcium cyclohexane-1,2-dicarboxylate, aluminum monobasic cyclohexane-1,2-dicarboxylate, dilithium cyclohexane-1,2-dicarboxylate, or strontium cyclohexane-1,2-dicarboxylate), and combinations thereof. In the bicyclo[2.2.1]heptane-2,3-dicarboxylates and cyclohexane-1,2-dicarboxylates, the carboxylate moieties may be arranged in either the cis or trans configuration, with the cis configuration being preferred. Suitable fining agents include, but are not limited to, trisamide and acetal compounds that are condensation products of polyhydric alcohols and aromatic aldehydes. Suitable trisamide clarifiers include, but are not limited to, amide derivatives of benzene-1,3,5-tricarboxylic acid, amide derivatives of 1,3,5-benzenetriamine, derivatives of N-(3,5-bis-formylamino-phenyl)-formamide (e.g., N-[3,5-bis-(2,2-dimethyl-propionylamino)-phenyl]-2,2-dimethyl-propionamide), derivatives of 2-carbamoyl-malonamide (e.g., N,N'-bis-(2-methyl-cyclohexyl)-2-(2-methyl-cyclohexylcarbamoyl)-malonamide), and combinations thereof.As indicated above, the clarifier may be an acetal compound, which is a condensation product of a polyhydric alcohol and an aromatic aldehyde. Suitable polyhydric alcohols include acyclic polyols, such as xylitol and sorbitol, and acyclic deoxypolyols (e.g., 1,2,3-trideoxynonitol or 1,2,3-trideoxynon-1-enitol). Suitable aromatic aldehydes typically contain a single aldehyde group, with the remaining positions of the aromatic ring being unsubstituted or substituted. Thus, suitable aromatic aldehydes include benzaldehyde and substituted benzaldehydes (e.g., 3,4-dimethylbenzaldehyde, 3,4-dichlorobenzaldehyde, or 4-propylbenzaldehyde). The acetal compound produced by the above reaction may be a monoacetal, diacetal, or triacetal compound (i.e., a compound containing one, two, or three acetal groups, respectively), with diacetal compounds being preferred. Suitable acetal-based fining agents include, but are not limited to, those disclosed in U.S. Patents 5,049,605; 7,157,510; and 7,262,236. Some particularly preferred fining agents include 1,3:2,4-bis-O-(phenylmethylene)-D-glucitol, 1,3:2,4-bis-O-[(4-methylphenyl)methylene]-D-glucitol, 1,3:2,4-bis-O-[(3,4-dimethylphenyl)methylene]-D-glucitol, 1,3:2,4-bis-O-[(3,4-dichlorophenyl)methylene]-D-glucitol, 1,2,3-trideoxy-4,6:5,7-bis-O-[(4-propylphenyl)methylene]nonitol, and mixtures thereof.

[0050]

[0048] When present in the master batch composition, the nucleating agent and / or clarifying agent can be present in any suitable amount. Preferably, the nucleating agent and / or clarifying agent is present in an amount of about 1 wt% or more based on the total weight of the master batch composition. More preferably, the nucleating agent and / or clarifying agent is present in the master batch composition in an amount of about 2 wt% or more, about 3 wt% or more, about 4 wt% or more, about 5 wt% or more, about 6 wt% or more, about 7 wt% or more, about 8 wt% or more, about 9 wt% or more, or about 10 wt% or more based on the total weight of the master batch composition. Preferably, the nucleating agent and / or clarifying agent is present in the master batch composition in an amount of about 40 wt% or less based on the total weight of the master batch composition. Thus, in a series of preferred embodiments, the nucleating and / or clarifying agent is present in the master batch composition in an amount of about 1 wt% to about 40 wt%, about 2 wt% to about 40 wt%, about 3 wt% to about 40 wt%, about 4 wt% to about 40 wt%, about 5 wt% to about 40 wt%, about 6 wt% to about 40 wt%, about 7 wt% to about 40 wt%, about 8 wt% to about 40 wt%, about 9 wt% to about 40 wt%, or about 10 wt% to about 40 wt%, based on the total weight of the master batch composition. When the master batch composition includes more than one nucleating and / or clarifying agent, the combined amount of both is preferably within the ranges recited above.

[0051] In an embodiment of the method described above, the compatibilizer can be provided in the form of a concentrated composition comprising (a) an antioxidant and (b) an ester compound as described above. The concentrated composition is preferably solid (or semi-solid) at ambient temperature (e.g., a temperature of about 25° C.) for ease of handling. The concentrated composition can be used in the method described above as a means for introducing the ester compound.

[0052] The concentrated composition can contain any suitable antioxidant or mixture of antioxidants. Preferably, the concentrated composition contains an antioxidant selected from the group consisting of hindered phenol compounds, hindered amine compounds, phosphite compounds, phosphonite compounds, thiol compounds, and mixtures thereof. Suitable antioxidant compounds include pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate) (CAS No. 6683-19-8), octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (CAS No. 2082-79-3), tris(2,4-di-tert-butylphenyl)phosphite (CAS No. 31570-04-4), 3,9-bis[2,4-bis(1,1-dimethylethyl)phenoxy]-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane (CAS No. 26741-53-7), bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidyl)sebacate (CAS No. No. 129757-67-1), bis(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate (CAS No. 41556-26-7), methyl-1,2,2,6,6-pentamethyl-4-piperidyl sebacate (CAS No. 82919-37-7), didodecyl-3,3'-thiodipropionate (CAS No. 123-28-4), 3,3'-thiodipropionic acid dioctadecyl ester (CAS No. 693-36-7), and tetrakis(2,4-di-t-butylphenyl) 4,4'-biphenylene diphosphonate (CAS No. 119345-01-6). In a preferred embodiment, the concentrated composition comprises a hindered phenol antioxidant, more preferably a 2,6-di-tert-butylphenol compound (ie, a compound that contains at least one 2,6-di-tert-butylphenol moiety).

[0053]

[0051] The antioxidant can be present in the concentrated composition in any suitable amount. Preferably, the antioxidant is present in the concentrated composition in an amount of about 5 wt% or more, based on the total weight of the concentrated composition. More preferably, the antioxidant is present in the concentrated composition in an amount of about 8 wt% or more, or about 10 wt% or more, based on the total weight of the concentrated composition. Preferably, the antioxidant is present in the concentrated composition in an amount of about 85 wt% or less (e.g., about 80 wt% or less, about 70 wt% or less, about 60 wt% or less, or about 50 wt% or less), based on the total weight of the concentrated composition. Thus, in a set of preferred embodiments, the antioxidant can be present in the concentrated composition in an amount of about 5 wt% to about 85 wt% (e.g., about 5 wt% to about 80 wt%, about 5 wt% to about 70 wt%, about 5 wt% to about 60 wt%, or about 5 wt% to about 50 wt%), about 8 wt% to about 85 wt% (e.g., about 8 wt% to about 80 wt%, about 8 wt% to about 70 wt%, about 8 wt% to about 60 wt%, or about 80 wt% to about 50 wt%), or about 10 wt% to about 85 wt% (e.g., about 10 wt% to about 80 wt%, about 10 wt% to about 70 wt%, about 10 wt% to about 60 wt%, or about 10 wt% to about 50 wt%). When the concentrated composition contains two or more antioxidants, the combined amount of both antioxidants is preferably within the ranges recited above.

[0054]

[0052] As indicated above, the concentrated composition includes an ester compound. The ester compound in the concentrated composition may be any of the ester compounds discussed above in connection with the first method embodiment of the present invention, including the preferred ester compounds identified in connection with the first method embodiment. The concentrated composition may contain any suitable amount of the ester compound. Preferably, the ester compound is present in the concentrated composition in an amount of about 1 wt% or more, based on the total weight of the concentrated composition. More preferably, the ester compound is present in the concentrated composition in an amount of about 2 wt% or more, about 3 wt% or more, about 4 wt% or more, about 5 wt% or more, about 6 wt% or more, about 7 wt% or more, about 8 wt% or more, about 9 wt% or more, or about 10 wt% or more, based on the total weight of the concentrated composition. Preferably, the ester compound is present in the concentrated composition in an amount of about 85 wt% or less (e.g., about 80 wt% or less, about 70 wt% or less, about 60 wt% or less, about 50 wt% or less, or about 40 wt% or less), based on the total weight of the concentrated composition. Thus, in a series of preferred embodiments, the ester compound is present in the concentrated composition in an amount of from about 1 wt% to about 85 wt%, from about 2 wt% to about 85 wt%, from about 3 wt% to about 85 wt%, from about 4 wt% to about 85 wt%, from about 5 wt% to about 85 wt%, from about 6 wt% to about 85 wt%, from about 7 wt% to about 85 wt%, from about 8 wt% to about 85 wt%, from about 9 wt% to about 85 wt%, or from about 10 wt% to about 85 wt%, based on the total weight of the concentrated composition.

[0055]

[0053] As with the masterbatch composition, the concentrated composition may contain other polymeric additives in addition to the antioxidant and ester compound. Suitable additional polymeric additives include those discussed above in connection with the masterbatch composition of the present invention, such as nucleating agents and clarifiers. These polymeric additives may be present in the concentrated composition in any suitable amount. For example, when present in the concentrated composition, the nucleating agent and / or clarifier may be present in an amount of about 1 wt% or more, based on the total weight of the concentrated composition. More preferably, the nucleating agent and / or clarifier is present in the concentrated composition in an amount of about 2 wt% or more, about 3 wt% or more, about 4 wt% or more, about 5 wt% or more, about 6 wt% or more, about 7 wt% or more, about 8 wt% or more, about 9 wt% or more, or about 10 wt% or more, based on the total weight of the concentrated composition. Preferably, the nucleating agent and / or clarifier is present in the concentrated composition in an amount of about 80 wt% or less, based on the total weight of the concentrated composition. Thus, in a series of preferred embodiments, the nucleating and / or clarifying agent is present in the concentrated composition in an amount of about 1 wt% to about 80 wt%, about 2 wt% to about 80 wt%, about 3 wt% to about 80 wt%, about 4 wt% to about 80 wt%, about 5 wt% to about 80 wt%, about 6 wt% to about 80 wt%, about 7 wt% to 80 wt%, about 8 wt% to about 80 wt%, about 9 wt% to about 80 wt%, or about 10 wt% to about 80 wt%, based on the total weight of the concentrated composition. When the concentrated composition includes more than one nucleating and / or clarifying agent, the combined amount of both is preferably within the ranges recited above.

[0056] In a third aspect, the present invention provides a modified polymer composition, for example a modified polymer composition produced by the process described herein. In particular, the present invention provides a modified polymer composition comprising (a) a heterophasic thermoplastic polymer composition comprising a propylene continuous phase and an ethylene discontinuous phase, and (b) a compatibilizer. The heterophasic thermoplastic polymer composition in the modified polymer composition may be any of the heterophasic thermoplastic polymer compositions described above in connection with the process aspects of the present invention. The compatibilizer present in the modified polymer composition comprises an ester compound formally derived from (i) a polyol comprising three or more hydroxy groups and (ii) an aliphatic carboxylic acid comprising one or more carbon-carbon double bonds. The compatibilizer present in the modified polymer composition may be any of the compatibilizers described above in connection with the process aspects of the present invention.

[0057] Heterophasic thermoplastic polymer compositions that exhibit good impact properties generally have a discontinuous phase with a small particle size (e.g., about 1 μm or less) and good adhesion to the continuous phase. However, it has also been shown that a small particle size in the discontinuous phase alone is not sufficient to provide the level of impact strength desired in the industry. Without wishing to be bound by any particular theory, the present inventors believe that they have discovered that achieving the desired level of impact strength requires a small particle size as well as a sufficient amount of such particles dispersed within the continuous phase. Since the amount or number of particles that can occupy a given space is related to the diameter of the particles, the present inventors have found that these two factors can be combined and expressed as a minimum concentration of particles per volume unit as described below.

[0058] In the modified polymer composition, the ethylene discontinuous phase is present in the form of discrete particles dispersed within the propylene continuous phase. The discrete particles of the ethylene discontinuous phase are preferably present in the modified polymer composition at a concentration of 2.1 particles per cubic micron or more. In more preferred embodiments, the discrete particles of the ethylene discontinuous phase are present in the modified polymer composition at a concentration of 2.2 particles per cubic micron or more, 2.3 particles per cubic micron or more, or 2.4 particles per cubic micron or more. The discrete particles of the ethylene discontinuous phase are preferably present in the modified polymer composition at a concentration of 100 particles per cubic micron or less. Thus, in a series of preferred embodiments, the discrete particles of the ethylene discontinuous phase are present in the modified polymer composition at a concentration of from 2.1 to 100 particles per cubic micron, from 2.2 to 100 particles per cubic micron, from 2.3 to 100 particles per cubic micron, or from 2.4 to 100 particles per cubic micron.

[0059] The particle concentration of the ethylene discontinuous phase is preferably determined using the method described in this paragraph. Standard injection molded bars used for impact testing are cooled with liquid nitrogen and then crushed approximately 1 inch (2.5 cm) from the end of the bar. The rubber at the interface is removed by sonication in methylcyclohexane. The sample is fixed in a 45° wedge for 90° cross-sectional imaging and gold coated. Images are then generated using a scanning electron microscope (e.g., ESEM FEI Quanta 400F) under conditions of high vacuum, low 5.0-10.0 keV, low 3.0-3.5 spot, approximately 12 WD (working distance), and imaged with an ETD secondary electron detector (i.e., Everhart-Thornley detector). Images are collected near the center of the cross-section at 5000X magnification. Image analysis software is then used to identify and size the particles. The area-equivalent diameter of the particles is calculated according to ISO 13322-1 "Particle size analysis - Image analysis methods - Part 1: Still image analysis methods". The distribution of area-equivalent diameters is then averaged to produce the mean volume diameter [i.e., D(4,3)] according to ASTM E799. The particle concentration is then calculated as the ratio of the soluble fraction (determined as described above) to the particle volume (calculated using the equation for the volume of a spherical particle with diameter D(4,3)). The particle concentration has units of particles per cubic micron, and the particle concentration is also expressed in μm -3 It can be expressed as:

[0060] The compatibilizer can be present in the modified polymer composition in any suitable amount. Preferably, the compatibilizer is present in the modified polymer composition in an amount that provides about 50 to about 5,000 ppm of the ester compound in the modified polymer composition. More preferably, the compatibilizer is present in the modified polymer composition in an amount that provides about 50 to about 4,000 ppm (e.g., about 50 to about 3,000 ppm, about 50 to about 2,000 ppm, or about 50 to about 1,500 ppm) of the ester compound in the modified polymer composition.

[0061]

[0059] In addition to the heterophasic thermoplastic polymer composition and the compatibilizer comprising an ester compound, the modified polymer composition may contain other polymer additives. Suitable additional polymer additives include, but are not limited to, any of the additives discussed above in connection with the masterbatch composition and concentrated composition forms, and the compatibilizer may be provided for use in the disclosed method.

[0062] The following examples further illustrate the subject matter described above but, of course, should not be construed as in any way limiting its scope. Unless indicated, the following methods were used to determine the properties described in the following examples.

[0063] Each of the compositions was mixed by blending the components in a closed container for approximately 1 minute. The compositions were then melt mixed on a twin screw extruder using typical processing conditions for polypropylene injection molding grades. The extrudates (in the form of strands) for each polypropylene copolymer composition were cooled in a water bath and subsequently pelletized.

[0064] The pelletized composition was then used to form bars by injection molding the composition under conditions typical for polypropylene injection molding grades to produce sample test bars of ISO or ASTM size, the bars having dimensions conforming to the corresponding standards.

[0065]

[0063] The melt flow rate (MFR) was determined for the pelletized compositions at 230°C under a load of 2.16 kg for polypropylene according to ASTM D1238 or ISO 1133.

[0066]

[0064] The notched Izod impact strength was measured on the bars according to ISO 180 / A method or ASTM D256 method. The notched Izod impact strength was measured at +23°C on bars conditioned at +23°C.

[0067]

[0065] The notched Charpy impact strength was measured on the bars according to ISO 179. The notched Charpy impact strength was measured at +23°C on bars conditioned at +23°C.

[0068] The solution properties of the polymers (e.g., soluble fraction, ethylene content of the soluble fraction, intrinsic viscosity, etc.) were measured using a Crystex® 42 analyzer (Polymer Char, Valencia, Spain) and 1,2,4-trichlorobenzene stabilized with 300 ppm of pentaerythritol tetrakis (3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate). A 160 mg sample of the polymer was dissolved in 16 mL of solvent. The sample volume injected into the analyzer was 0.3 mL. The dissolution temperature was 160° C., the crystallization temperature was 40° C., and the analysis temperature was 165° C. The dissolution time was 90 min and the stirring was set high. The crystallization time was 40 min. The term β / α is the ratio of the respective intrinsic viscosities of the soluble fraction to the crystalline fraction. The soluble fraction (SF) and the ethylene content of the soluble fraction (C2 SF ) was also decided on Crystex-42.

[0069] The particle size of the ethylene discontinuous phase was determined as follows: Standard injection molded bars used for impact testing were cooled in liquid nitrogen and then crushed approximately 1 inch from the bar end. The rubber at the interface was removed by sonication in methylcyclohexane. Samples were mounted in a 45° wedge for 90° cross-sectional imaging and gold coated. Images were generated using an ESEM FEI Quanta 400F scanning electron microscope under high vacuum, low 5.0-10.0 keV, low 3.0-3.5 spot, approximately 12 WD (working distance) and imaged with an ETD secondary electron detector (Everhart-Thornley detector). Images were collected near the center of the cross section at 5000X magnification. Image analysis software was used to identify and size the particles. The area equivalent diameter was calculated according to ISO 13322-1 "Particle size analysis - Image analysis methods - Part 1: Still image analysis methods". The distribution of area-equivalent diameters was averaged to generate the mean volume diameter [i.e., D(4,3)] according to ASTM E799. Particle concentration was calculated as the ratio of the soluble fraction (determined using a Crystex® 42 analyzer as described above) to particle volume (calculated using the equation for the volume of a spherical particle with diameter D(4,3)). Particle concentration was determined in units of particles per cubic micron. Particle concentration is now expressed in μm -3 This is expressed as:

[0070] Example 1 In the context of the process of the present invention, this example illustrates the effect of C2 SF Demonstrate the effect of.

[0071] A total of six polymer compositions (Samples 1A-1F) were made from one of two polypropylene impact copolymers, Total 5720WZ or ExxonMobil PP7414. The impact copolymers were modified with peroxide alone (Samples 1B and 1E) or with peroxide and a compatibilizer (Samples 1C and 1F). The peroxide was Varox DBPH available from Vanderbilt Chemicals, LLC. The compatibilizer was 2,2-bis[(1,3-pentadienylcarbonyloxy)methyl]butyl 2,4-hexadienoate (CAS No. 347377-00-8). The peroxide and compatibilizer loadings are listed in Table 1B below.

[0072] Table 1A shows the MFR, SF, and C2 for two polymers, polypropylene impact copolymer, Total 5720WZ and ExxonMobil PP7414. SF For inequalities 1, 2, and 3 above, we obtain the values ​​of R1, R2, and R3 by substituting these values ​​into the equations. Table 1A reports whether these values ​​are greater than zero, which indicates the MFR, SF, and C2 for the polymer. SF satisfies the corresponding inequality.

[0073] [Table 1]

[0074] The components for each polymer composition were mixed and extruded into pellets as described above, and a portion of the pellets for each composition was injection molded into bars according to the general procedure described above. The extruded pellets were used to determine the melt flow rate (MFR) exhibited by the polymer compositions, and the injection molded bars were tested to determine Izod impact strength as described above. The soluble fraction, ethylene content of the soluble fraction, and β / α (before treatment with compatibilizer and / or peroxide) for each polypropylene impact copolymer were determined using a Crystex® 42 analyzer according to the method described above. The results of this testing are set forth below in Table 1B.

[0075] [Table 2]

[0076] As can be seen from the data in Table 1A, the unmodified 5720WZ resin has MFR, SF, and C2 that satisfy inequality 1 (as well as satisfying both inequalities 2 and 3). SF When this resin was modified with a compatibilizer to produce Sample 1C, the resin exhibited a significantly increased MFR compared to the untreated resin, and its impact strength changed from complete failure to no failure, indicating an increase in impact strength. In contrast, no such impact behavior was observed for the PP7414 resin, which failed to satisfy inequality 1 (as well as inequality 2) and exhibited complete failure both before and after modification.

[0077]

[0073] The responsive resin modified with a compatibilizer has a particle size of 3.4 μm. -3 and the non-responsive resin has a particle concentration of 1.4 μm -3 The PP7414 peroxide modified resin also had a significantly lower particle concentration than the compatibilizer modified resin. Example 2 In the context of the process of the present invention, this example illustrates the effect of C2SF Demonstrate the effect of.

[0078] A total of six polymer compositions (Samples 2A-2F) were made from polypropylene impact copolymers Braskem C702-20 or ExxonMobil PP7654KNE2. The impact copolymers were modified with peroxide alone (Samples 2B and 2E) or with peroxide and a compatibilizer (Samples 2C and 2F). The peroxide was Varox DBPH available from Vanderbilt Chemicals, LLC. The compatibilizer was 2,2-bis[(1,3-pentadienylcarbonyloxy)methyl]butyl 2,4-hexadienoate (CAS#347377-00-8). The peroxide and compatibilizer loadings are listed in Table 2B below.

[0079] Table 2A shows the MFR, SF, and C2 for two polymer polypropylene impact copolymers. SF For inequalities 1, 2, and 3 above, the values ​​of R1, R2, and R3 are obtained by substituting these values ​​into the equations. Table 2A reports whether these values ​​are greater than zero, which indicates the MFR, SF, and C2 for the polymer. SF satisfies the corresponding inequality.

[0080] [Table 3]

[0081] The components for each polymer composition were mixed and extruded into pellets as described above, and a portion of the pellets for each composition was injection molded into bars according to the general procedure described above. The extruded pellets were used to determine the melt flow rate (MFR) exhibited by the polymer compositions, and the injection molded bars were tested to determine Izod impact strength as described above. The soluble fraction and β / α (before treatment with compatibilizer and / or peroxide) for each polypropylene impact copolymer were determined using a Crystex® 42 analyzer according to the method described above. The results of this testing are set forth below in Table 2B.

[0082] [Table 4]

[0083] As shown in Table 2A, the unmodified C702-20 resin has MFR, SF, and C2 that satisfy inequality 1 (and also satisfy both inequalities 2 and 3). SF When modified with a compatibilizer to produce Sample 2C, the resin exhibited a significantly increased MFR compared to the untreated resin, and the impact type changed from complete failure to a mixture of partial and no failure, indicating increased impact strength. This behavior was not demonstrated for PP7654KNE2 resin, which failed to satisfy inequality 1 (as well as inequality 2), exhibiting complete failure both before and after modification.

[0084]

[0079] The responsive resin modified with a compatibilizer has a particle size of 2.5 μm. -3 and the non-responsive resin has a particle concentration of 2.0 μm -3 The peroxide modified resin also had a significantly lower particle concentration than the compatibilizer modified resin. Example 3 In the context of the process of the present invention, this example demonstrates the effect of the soluble fraction in an unmodified heterophasic polyolefin composition.

[0085] A total of six polymer compositions (Samples 3A-3F) were made from one of two polypropylene impact copolymers, ExxonMobil PP7143KNE1 or Lyondell Basell Pro-faxSD375S. The impact copolymers were modified with peroxide alone (Samples 3B and 3E) or with peroxide and a compatibilizer (Samples 3C and 3F). The peroxide was Varox DBPH available from Vanderbilt Chemicals, LLC. The compatibilizer was 2,2-bis[(1,3-pentadienylcarbonyloxy)methyl]butyl 2,4-hexadienoate (CAS#347377-00-8). The peroxide and compatibilizer loadings are listed in Table 3B below.

[0086] Table 3A shows the MFR, SF, and C2 for two polymer polypropylene impact copolymers. SF For inequalities 1, 2, and 3 above, the values ​​of R1, R2, and R3 are obtained by substituting these values ​​into the equations. Table 3A reports whether these values ​​are greater than zero, which indicates the MFR, SF, and C2 for the polymer. SF satisfies the corresponding inequality.

[0087] [Table 5]

[0088] The components for each polymer composition were mixed and extruded into pellets as described above, and a portion of the pellets for each composition was injection molded into bars according to the general procedure described above. The extruded pellets were used to determine the melt flow rate (MFR) exhibited by the polymer compositions, and the injection molded bars were tested to determine Izod impact strength as described above. The soluble fraction and β / α (before treatment with compatibilizer and / or peroxide) for each polypropylene impact copolymer were determined using a Crystex® 42 analyzer according to the method described above. The results of this testing are set forth below in Table 3B.

[0089] [Table 6]

[0090]

[0084] The unmodified 7143KNE1 resin has MFR, SF, and C2 that satisfy inequality 1 (as well as satisfying both inequalities 2 and 3). SF Upon modification with a compatibilizer to produce Sample 3C, the resin exhibited a significant increase in MFR compared to the virgin resin and maintained its non-fracture behavior, which is highly desirable. Similar behavior was not demonstrated for SD375S resin, which failed to satisfy inequality 1 (as well as inequality 2) and exhibited complete fracture failure both before and after modification.

[0091]

[0085] Responsive resin modified with compatibilizer, 7143KNE1, is 2.4 μm -3 The non-responsive resin, SD375S, has a particle concentration of 0.47 μm -3 The peroxide modified resin also had a significantly lower particle concentration than the compatibilizer modified resin. Example 4 In the context of the process of the present invention, this example demonstrates the effect of the soluble fraction in an unmodified heterophasic polyolefin composition.

[0092] A total of six polymer compositions (Samples 4A-4F) were made from one of two polypropylene impact copolymers, Japan Polypropylene BC3F or BC3AD. The impact copolymers were modified with peroxide alone (Samples 4B and 4E) or with peroxide and a compatibilizer (Samples 4C and 4F). The peroxide was Varox DBPH available from Vanderbilt Chemicals, LLC. The compatibilizer was 2,2-bis[(1,3-pentadienylcarbonyloxy)methyl]butyl 2,4-hexadienoate (CAS#347377-00-8). The amounts of peroxide and compatibilizer added are listed in Table 4B below.

[0093] Table 4A shows the MFR, SF, and C2 for two polymer polypropylene impact copolymers. SF For inequalities 1, 2, and 3 above, the values ​​of R1, R2, and R3 are obtained by substituting these values ​​into the equations. Table 4A reports whether these values ​​are greater than zero, which indicates the MFR, SF, and C2 for the polymer. SF satisfies the corresponding inequality.

[0094] [Table 7]

[0095] The components for each polymer composition were mixed and extruded into pellets as described above, and a portion of the pellets for each composition was injection molded into bars following the general procedure described above. The extruded pellets were used to determine the melt flow rate (MFR) exhibited by the polymer compositions, and the injection molded bars were tested to determine the Charpy impact strength as described above. The soluble fraction and β / α (before treatment with compatibilizer and / or peroxide) for each polypropylene impact copolymer were determined using a Crystex® 42 analyzer according to the method described above. The results of the testing are set forth below in Table 4B.

[0096] [Table 8]

[0097] As can be seen from the data in Table 4A, the unmodified BC3F resin has MFR, SF, and C2 that satisfy inequality 1 (as well as both inequalities 2 and 3). SF When modified with a compatibilizer to produce sample 4C, the BC3F resin exhibited a significantly increased MFR compared to the untreated resin and its impact type changed from complete to partial failure, indicating increased impact strength. This behavior was not demonstrated for the BC3AD resin, which failed to satisfy inequality 1 (as well as both inequalities 2 and 3) and exhibited complete failure both before and after modification. Example 5 In the context of the process of the present invention, this example demonstrates the effect of the soluble fraction of an unmodified heterophasic polyolefin composition.

[0098] A total of six polymer compositions (Samples 5A-5F) were made from one of two polypropylene impact copolymers, LyondellBasell Pro-fax SG702 or ExxonMobil PP7033N. The impact copolymers were modified with peroxide alone (Samples 5B and 5E) or with peroxide and a compatibilizer (Samples 5C and 5F). The peroxide was Varox DBPH available from Vanderbilt Chemicals, LLC. The compatibilizer was 2,2-bis[(1,3-pentadienylcarbonyloxy)methyl]butyl 2,4-hexadienoate (CAS#347377-00-8). The peroxide and compatibilizer loadings are listed in Table 5B below.

[0099] Table 5A shows the MFR, SF, and C2 for two polymer polypropylene impact copolymers. SF For inequalities 1, 2, and 3 above, the values ​​of R1, R2, and R3 are obtained by substituting these values ​​into the equations. Table 5A reports whether these values ​​are greater than zero, which indicates the MFR, SF, and C2 for the polymer. SF satisfies the corresponding inequality.

[0100] [Table 9]

[0101] The components for each polymer composition were mixed and extruded into pellets as described above, and a portion of the pellets for each composition was injection molded into bars following the general procedure described above. The extruded pellets were used to determine the melt flow rate (MFR) exhibited by the polymer compositions, and the injection molded bars were tested to determine Charpy impact strength as described above. The soluble fraction and β / α (before treatment with compatibilizer and / or peroxide) for each polypropylene impact copolymer were determined using a Crystex® 42 analyzer according to the method described above. The results of this testing are set forth below in Table 5B.

[0102] [Table 10]

[0103] The data in Table 5A show that the unmodified SG702 resin satisfies inequality 1 (as well as satisfies both inequalities 2 and 3) and has MFR, SF, and C2 SF When modified with a compatibilizer to produce Sample 5C, the resin exhibited a significantly increased MFR compared to the untreated resin, and its impact failure changed from complete to partial failure, indicating increased impact strength. Similar behavior was not demonstrated for the PP7033N resin, which failed to satisfy inequality 1 (as well as inequality 2) and exhibited complete failure both before and after modification.

[0104]

[0096] The responsive resin modified with a compatibilizer has a particle size of 2.7 μm. -3 and the non-responsive resin has a particle concentration of 1.9 μm -3 The peroxide modified resin also had a significantly lower particle concentration than the compatibilizer modified resin. Example 6 In the context of the process of the present invention, this example demonstrates the effect of the soluble fraction in an unmodified heterophasic polyolefin composition.

[0105] A total of six polymer compositions (Samples 6A-6F) were made from one of two polypropylene impact copolymers, Japan Polypropylene NBX03HRS and Prime Polymer J707. The impact copolymers were modified with either peroxide alone (Samples 6B and 6E) or with peroxide and a compatibilizer (Samples 6C and 6F). The peroxide was Varox DBPH available from Vanderbilt Chemicals, LLC. The compatibilizer was 2,2-bis[(1,3-pentadienylcarbonyloxy)methyl]butyl 2,4-hexadienoate (CAS#347377-00-8). The amounts of peroxide and compatibilizer added are listed in Table 6B below.

[0106] Table 6A shows the MFR, SF, and C2 for two polymer polypropylene impact copolymers. SF For inequalities 1, 2, and 3 above, the values ​​of R1, R2, and R3 are obtained by substituting these values ​​into the equations. Table 6A reports whether these values ​​are greater than zero, which indicates the MFR, SF, and C2 for the polymer. SF satisfies the corresponding inequality.

[0107] [Table 11]

[0108] The components for each polymer composition were mixed and extruded into pellets as described above, and a portion of the pellets for each composition was injection molded into bars according to the general procedure described above. The extruded pellets were used to determine the melt flow rate (MFR) exhibited by the polymer compositions, and the injection molded bars were tested to determine Izod impact strength as described above. The soluble fraction and β / α (before treatment with compatibilizer and / or peroxide) for each polypropylene impact copolymer were determined using a Crystex® 42 analyzer according to the method described above. The results of this testing are set forth below in Table 6B.

[0109] [Table 12]

[0110] As can be seen from the data in Table 6A, the unmodified NBX03HRS resin has MFR, SF, and C2 that satisfy inequality 1 (as well as both inequalities 2 and 3). SF Furthermore, when this resin was modified with a compatibilizer to produce Sample 6C, it exhibited a significantly increased MFR compared to the untreated resin and its impact strength maintained non-fracture behavior, which is desirable. This behavior was not demonstrated with J707 resin, which failed to satisfy inequality 1 (as well as both inequalities 2 and 3) and exhibited complete fracture failure both before and after modification.

[0111]

[0102] The responsive resin modified with a compatibilizer (sample 6C) had a particle size of 6.3 μm. -3 and the non-responsive resin has a particle concentration of 2.0 μm -3 The peroxide modified NBX03HRS (Sample 6B) also had a significantly lower particle concentration than the compatibilizer modified example.

[0112]

[0103] All references cited herein, including publications, patent applications, and patents, are incorporated by reference herein to the same extent as if each individual reference was individually and specifically indicated to be incorporated by reference herein and was set forth in its entirety.

[0113]

[0104] The use of the terms "a" and "an" and "the" and similar references in the context of describing the subject matter of this application (particularly in the context of the claims below) should be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms "comprising," "having," "including," and "containing" should be construed as open-ended (i.e., meaning "including, but not limited to"), unless otherwise indicated. The recitation of ranges of values ​​herein is intended merely to serve as a shorthand method of individually referring to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein, unless otherwise specified. All methods described herein can be performed in any suitable order, unless otherwise indicated herein or clearly contradicted by context. Any and all examples or exemplary language (e.g., "such as") provided herein are intended only to better elucidate the subject matter of the present application and do not impose limitations on the scope of the subject matter unless specifically claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the subject matter described herein.

[0114]

[0105] Preferred embodiments of the subject matter of this application are described herein, including the best mode known to the inventors for carrying out the claimed subject matter. Variations of these preferred embodiments may become apparent to those skilled in the art upon reading the foregoing description. The inventors anticipate that those skilled in the art will utilize such variations as appropriate, and the inventors intend that the subject matter described herein be practiced in ways other than as specifically described herein. Accordingly, this disclosure includes all modifications and equivalents of the subject matter recited in the appended claims to the extent permitted by applicable law. Moreover, any combination of all possible variations of the elements described above is encompassed in this disclosure unless otherwise indicated herein or otherwise clearly contradicted by the context. The invention as described in the claims of the present application as originally filed is set forth below. [1] A method for making a modified polymer composition, comprising: (a) providing a heterophasic thermoplastic polymer composition comprising a propylene continuous phase and an ethylene discontinuous phase, the heterophasic thermoplastic polymer composition having a melt flow rate (MFR), a soluble fraction (SF), and an ethylene content (C2 SF ), wherein the MFR (expressed in g / 10 min), the SF (expressed in wt%), and the C2 SF (expressed in wt%) is subject to the following inequality: (i)0<(-0.29×MFR)+(1.269×SF)-(0.626×C2 SF )+5.9 A process that satisfies the above. (b) providing a compatibilizer, the compatibilizer comprising an ester compound formally derived from a polyol containing three or more hydroxy groups and an aliphatic carboxylic acid containing one or more carbon-carbon double bonds; (c) providing a peroxide compound; (d) feeding the heterophasic thermoplastic polymer composition, the compatibilizer, and the peroxide compound into a melt mixing device; (e) processing the heterophasic thermoplastic polymer composition, the compatibilizer, and the peroxide compound in the melt mixing device at a temperature above the melting point of the heterophasic thermoplastic polymer composition to form a polymer composition. A method comprising: [2] A method for making a modified polymer composition, comprising: (a) providing a heterophasic thermoplastic polymer composition comprising a propylene continuous phase and an ethylene discontinuous phase, the heterophasic thermoplastic polymer composition having a melt flow rate (MFR), a soluble fraction (SF), and an ethylene content (C2 SF ), wherein the MFR (expressed in g / 10 min), the SF (expressed in wt%), and the C2 SF (expressed in wt%) is subject to the following inequality: (i)0<(-0.29×MFR)+(1.269×SF)-(0.626×C2 SF )+5.9 A process that satisfies the above. (b) providing a compatibilizer, the compatibilizer comprising an ester compound formally derived from a polyol containing three or more hydroxy groups and an aliphatic carboxylic acid containing one or more carbon-carbon double bonds; (c) providing a peroxide compound; (d) combining the heterophasic thermoplastic polymer composition, the compatibilizer, and the peroxide compound to form an intermediate composition; (e) heating the intermediate composition to a temperature above the melting point of the heterophasic thermoplastic polymer composition; (f) mixing the intermediate composition to form a polymer composition; (g) cooling the polymer composition to a temperature at which it solidifies. A method comprising: [3] The propylene continuous phase is a mixture of polypropylene homopolymer, propylene and up to 50 wt% ethylene and C 4 ~C 10 The method according to [1] or [2], wherein the copolymer is selected from the group consisting of copolymers with one or more comonomers selected from the group consisting of α-olefin monomers. [4] The ethylene discontinuous phase is selected from the group consisting of ethylene homopolymer and ethylene and C 3 ~C 10 The method according to any one of [1] to [3], wherein the copolymer is selected from the group consisting of copolymers with a comonomer selected from the group consisting of α-olefin monomers. [5] The method according to [4], wherein the ethylene discontinuous phase is a copolymer of ethylene and propylene. [6] The method according to any one of [1] to [5], wherein the ester compound is formally derived by linking each of the hydroxy groups of the polyol with an aliphatic carboxylic acid. [7] The method according to any one of [1] to [6], wherein the polyol is 2-(hydroxymethyl)-2-ethylpropane-1,3-diol. [8] The method according to any one of [1] to [7], wherein the aliphatic carboxylic acid contains two or more carbon-carbon double bonds, and at least two of the carbon-carbon double bonds are conjugated. [9] The aliphatic carboxylic acid is 6 ~C 10 The method according to any one of [1] to [8], wherein the carboxylic acid is selected from the group consisting of aliphatic carboxylic acids.

[10] The method according to [9], wherein the aliphatic carboxylic acid is 2,4-hexadienoic acid.

[11] The method according to any one of [1] to

[10] , wherein the ester compound is 2,2-bis[(1,3-pentadienylcarbonyloxy)methyl]butyl 2,4-hexadienoate.

[12] The method according to any one of [1] to

[11] , wherein the peroxide compound is 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane.

[13] (a) a heterophasic thermoplastic polymer composition comprising a propylene continuous phase and an ethylene discontinuous phase; (b) a compatibilizer comprising (i) a polyol containing three or more hydroxy groups and (ii) an ester compound formally derived from an aliphatic carboxylic acid containing one or more carbon-carbon double bonds; A modified polymer composition comprising: A modified polymer composition, wherein said ethylene discontinuous phase is present in the form of discrete particles dispersed in said propylene continuous phase, said discrete particles of said ethylene discontinuous phase being present in said modified polymer composition at a concentration of 2.1 particles per cubic micron or greater.

[14] The propylene continuous phase is a mixture of polypropylene homopolymer, propylene and up to 50 wt% ethylene and C 4 ~C 10 The modified polymer composition according to

[13] , wherein the modified polymer composition is selected from the group consisting of copolymers with one or more comonomers selected from the group consisting of α-olefin monomers.

[15] The ethylene discontinuous phase is selected from the group consisting of ethylene homopolymer and ethylene and C 3 ~C 10 The modified polymer composition according to

[13] or

[14] , wherein the modified polymer composition is selected from the group consisting of copolymers with a comonomer selected from the group consisting of α-olefin monomers.

[16] The modified polymer composition of

[15] , wherein the ethylene discontinuous phase is a copolymer of ethylene and propylene.

[17] The modified polymer composition according to any one of

[13] to

[16] , wherein the ester compound is formally derived by linking each of the hydroxy groups of the polyol with an aliphatic carboxylic acid.

[18] The modified polymer composition according to any one of

[13] to

[17] , wherein the polyol is 2-(hydroxymethyl)-2-ethylpropane-1,3-diol.

[19] The modified polymer composition according to any one of

[13] to

[18] , wherein the aliphatic carboxylic acid contains two or more carbon-carbon double bonds, and at least two of the carbon-carbon double bonds are conjugated.

[20] The aliphatic carboxylic acid is 6 ~C 10 The modified polymer composition according to any one of

[13] to

[19] , wherein the modified polymer composition is selected from the group consisting of aliphatic carboxylic acids.

[21] The modified polymer composition according to

[20] , wherein the aliphatic carboxylic acid is 2,4-hexadienoic acid.

[22] The modified polymer composition according to any one of

[13] to

[21] , wherein the ester compound is 2,2-bis[(1,3-pentadienylcarbonyloxy)methyl]butyl 2,4-hexadienoate.

Claims

1. 1. A method for making a modified polymer composition, comprising: (a) providing a heterophasic thermoplastic polymer composition comprising a propylene continuous phase and an ethylene discontinuous phase, said heterophasic thermoplastic polymer composition having a melt flow rate (MFR), a soluble fraction (SF), and an ethylene content of said soluble fraction (C2 ＳＦ ), wherein the MFR (expressed in g / 10 min), the SF (expressed in wt%), and the C2 ＳＦ (expressed in wt%) is subject to the following inequality: (i)0<(-0.29×MFR)+(1.269×SF)-(0.626×C2 ＳＦ )+5.9 A process that satisfies the above. (b) providing a compatibilizer, the compatibilizer comprising an ester compound formally derived from a polyol containing three or more hydroxy groups and an aliphatic carboxylic acid containing two or more carbon-carbon double bonds, at least two of the carbon-carbon double bonds being conjugated; (c) providing a peroxide compound; (d) feeding the heterophasic thermoplastic polymer composition, the compatibilizer, and the peroxide compound into a melt mixing device; (e) processing the heterophasic thermoplastic polymer composition, the compatibilizer, and the peroxide compound in the melt mixing device at a temperature above the melting point of the heterophasic thermoplastic polymer composition to form a polymer composition. A method comprising:

2. 1. A method for making a modified polymer composition, comprising: (a) providing a heterophasic thermoplastic polymer composition comprising a propylene continuous phase and an ethylene discontinuous phase, said heterophasic thermoplastic polymer composition having a melt flow rate (MFR), a soluble fraction (SF), and an ethylene content of said soluble fraction (C2 ＳＦ ), wherein the MFR (expressed in g / 10 min), the SF (expressed in wt%), and the C2 ＳＦ (expressed in wt%) is subject to the following inequality: (i)0<(-0.29×MFR)+(1.269×SF)-(0.626×C2 ＳＦ )+5.9 A process that satisfies the above. (b) providing a compatibilizer, the compatibilizer comprising an ester compound formally derived from a polyol containing three or more hydroxy groups and an aliphatic carboxylic acid containing two or more carbon-carbon double bonds, at least two of the carbon-carbon double bonds being conjugated; (c) providing a peroxide compound; (d) combining the heterophasic thermoplastic polymer composition, the compatibilizer, and the peroxide compound to form an intermediate composition; (e) heating the intermediate composition to a temperature above the melting point of the heterophasic thermoplastic polymer composition; (f) mixing the intermediate composition to form a polymer composition; (g) cooling the polymer composition to a temperature at which it solidifies. A method comprising:

3. The propylene continuous phase is a mixture of polypropylene homopolymer, propylene and up to 50 wt % ethylene and C ４ ~C １０ The method according to claim 1 or claim 2, wherein the copolymer is selected from the group consisting of copolymers with one or more comonomers selected from the group consisting of α-olefin monomers.

4. The ethylene discontinuous phase is selected from the group consisting of ethylene homopolymer and ethylene and C ３ ~C １０ The method of any one of claims 1 to 3, wherein the copolymer is selected from the group consisting of copolymers with a comonomer selected from the group consisting of α-olefin monomers.

5. 5. The method of claim 4, wherein the ethylene discontinuous phase is a copolymer of ethylene and propylene.

6. 6. The method of claim 1, wherein the ester compound is formally derivatized by linking each of the hydroxy groups of the polyol with an aliphatic carboxylic acid.

7. The method according to any one of claims 1 to 6, wherein the polyol is 2-(hydroxymethyl)-2-ethylpropane-1,3-diol.

8. The aliphatic carboxylic acid is ６ ~C １０ The method according to any one of claims 1 to 7, wherein the carboxylic acid is selected from the group consisting of aliphatic carboxylic acids.

9. The method of claim 8, wherein the aliphatic carboxylic acid is 2,4-hexadienoic acid.

10. The method according to any one of claims 1 to 9, wherein the ester compound is 2,2-bis[(1,3-pentadienylcarbonyloxy)methyl]butyl 2,4-hexadienoate.

11. The method according to any one of claims 1 to 10, wherein the peroxide compound is 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane.

12. (a) a heterophasic thermoplastic polymer composition comprising a propylene continuous phase and an ethylene discontinuous phase; (b) a compatibilizer comprising an ester compound formally derived from (i) a polyol containing three or more hydroxy groups and (ii) an aliphatic carboxylic acid containing two or more carbon-carbon double bonds, at least two of the carbon-carbon double bonds being conjugated; A modified polymer composition comprising: A modified polymer composition, wherein said ethylene discontinuous phase is present in the form of discrete particles dispersed in said propylene continuous phase, said discrete particles of said ethylene discontinuous phase being present in said modified polymer composition at a concentration of 2.1 particles per cubic micron or greater.

13. The propylene continuous phase is a mixture of polypropylene homopolymer, propylene and up to 50 wt % ethylene and C ４ ~C １０ 13. The modified polymer composition of claim 12, selected from the group consisting of copolymers with one or more comonomers selected from the group consisting of α-olefin monomers.

14. The ethylene discontinuous phase is selected from the group consisting of ethylene homopolymer and ethylene and C ３ ~C １０ The modified polymer composition of claim 12 or claim 13, selected from the group consisting of copolymers with a comonomer selected from the group consisting of α-olefin monomers.

15. 15. The modified polymer composition of claim 14, wherein the ethylene discontinuous phase is a copolymer of ethylene and propylene.

16. 16. The modified polymer composition of any one of claims 12 to 15, wherein the ester compound is formally derived by linking each of the hydroxy groups of the polyol with an aliphatic carboxylic acid.

17. The modified polymer composition of any one of claims 12 to 16, wherein said polyol is 2-(hydroxymethyl)-2-ethylpropane-1,3-diol.

18. The aliphatic carboxylic acid is ６ ~C １０ The modified polymer composition of any one of claims 12 to 17, wherein the carboxylic acid is selected from the group consisting of aliphatic carboxylic acids.

19. 19. The modified polymer composition of claim 18, wherein said aliphatic carboxylic acid is 2,4-hexadienoic acid.

20. The modified polymer composition of any one of claims 12 to 19, wherein the ester compound is 2,2-bis[(1,3-pentadienylcarbonyloxy)methyl]butyl 2,4-hexadienoate.

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