Breathable film and method of making the breathable film

Abstract

The present disclosure provides breathable films and methods of making the breathable films. Breathable films according to the present disclosure include a film layer comprising a polymeric composition comprising a linear low density polyethylene resin equal to or less than 60 wt% that exhibits the following various properties: (1) a CEF fraction of 70 to 90°C equal to or greater than 80% of the total CEF fraction; (2) a melt index, I2, measured according to ASTM D 1238 (2.16 kg at 190°C) in the range equal to or greater than 2.0 g / 10 min and equal to or less than 5.0 g / 10 min; and (3) a melt flow ratio, I 10 / I2 equal to or less than 6.7.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to breathable films and methods of making the same. BACKGROUND

[0002] It is generally known to use polyethylene compositions, such as linear low density polyethylene, in the manufacture of breathable films. A typical process employs a cast film extrusion process with machine direction orientation to produce breathable films. In such processes, an extruded cast film is oriented in the machine direction until the desired basis weight (grams per square meter (GSM)) is achieved. Due to stress localization, it is difficult to obtain a uniform film appearance at low levels of orientation, which results in film defects such as tiger striping, i.e., highly deformed regions of the film adjacent to less deformed regions of the film. Each film formulation has an inherent "minimum draw ratio" to achieve the desired final basis weight without tiger striping. Only above the "minimum draw ratio" is the optical appearance of the film acceptable. Then, the film converter fine tunes the draw ratio (above the minimum draw ratio) to achieve the desired balance of mechanical properties. Therefore, formulations with low "minimum draw ratio" provide a wide process window as well as a wide range of final film properties while minimizing film defects.

[0003] Despite efforts to develop linear low density polyethylene compositions suitable for breathable film production applications, there remains a need for linear low density polyethylene compositions with improved machine direction orientation, i.e., low "minimum draw ratio", while providing improved breathable film properties such as improved water vapor transmission rate, shrinkage, and puncture strength. SUMMARY

[0004] The present disclosure provides breathable films and methods of making the same. In one embodiment, the present disclosure provides a breathable film comprising a film layer, the film layer comprising a polymeric composition comprising equal to or less than 60 wt% of a linear low density polyethylene resin that exhibits the following various properties: (1) a CEF fraction of 70 to 90°C equal to or greater than 80% of the total CEF fraction; (2) a melt index (I2) measured according to ASTM D 1238 (2.16 kg at 190°C) in the range of equal to or greater than 2.0 g / 10 min and equal to or less than 5.0 g / 10 min; and (3) a melt flow ratio (I10 / I2) equal to or less than 6.7. 10

[0005] ​In an alternative embodiment, the present disclosure further provides a method of making a breathable film comprising: (a) cast extruding a polymer composition comprising greater than 0 wt% to 60 wt% of a linear low density polyethylene that exhibits the following various properties: (1) a CEF fraction at 70 to 90 °C equal to or greater than 80% of the total CEF fraction; (2) a melt index (melt index) I2 measured according to ASTM D 1238 (2.16 kg at 190 °C) equal to or greater than 2.0 g / 10 min and equal to or less than 5 g / 10 min; and (3) a melt flow ratio I 10 / I2 equal to or less than 6.7, to make a cast extruded film layer; and (b) machine direction orienting the cast extruded film layer.

[0006] In an alternative embodiment, the present disclosure further provides a method of making a breathable film comprising: (a) blow extruding a polymer composition comprising greater than 0 wt% to 60 wt% of a linear low density polyethylene that exhibits the following various properties: (1) a CEF fraction at 70 to 90 °C equal to or greater than 80% of the total CEF fraction; (2) a melt index (melt index) I2 measured according to ASTM D 1238 (2.16 kg at 190 °C) equal to or greater than 2.0 g / 10 min and equal to or less than 5.0 g / 10 min; and (3) a melt flow ratio I 10 / I2 equal to or less than 6.7, to make a blown film layer; and (b) machine direction orienting the blown film layer.

[0007] In an alternative embodiment, the present disclosure further provides a breathable film and a method of making the breathable film according to any of the preceding embodiments, except that the linear low density polyethylene resin further exhibits a density (measured according to ASTM D792) of 0.915 to 0.940 g / cm 2 .

[0008] In an alternative embodiment, the present disclosure further provides a breathable film and a method of making the breathable film according to any of the preceding embodiments, except that the linear low density polyethylene comprises units derived from ethylene and units derived from one or more alpha-olefin comonomers.

[0009] In an alternative embodiment, the present disclosure further provides a breathable film and a method of making the breathable film according to any of the preceding embodiments, except that the comonomer is 1-hexene.

[0010] In an alternative embodiment, the present disclosure further provides a breathable film and a method of making the breathable film according to any of the preceding embodiments, except that the comonomer is 1-octene.

[0011] In an alternative embodiment, the present disclosure further provides a breathable film according to any of the preceding embodiments and a method of making the breathable film, except that the comonomer is 1-butene.

[0012] In an alternative embodiment, the present disclosure further provides a breathable film according to any of the preceding embodiments and a method of making the breathable film, except that the linear low density polyethylene resin does not contain units derived from octene.

[0013] In an alternative embodiment, the present disclosure further provides a breathable film according to any of the preceding embodiments and a method of making the breathable film, except that the polymer composition further comprises 40 to 60 wt% CaCC.

[0014] In an alternative embodiment, the present disclosure further provides a breathable film according to any of the preceding embodiments and a method of making the breathable film, except that the polymer composition comprises 30 to 60 wt% linear low density polyethylene resin.

[0015] In an alternative embodiment, the present disclosure further provides a breathable film according to any of the preceding embodiments and a method of making the breathable film, except that the polymer composition further comprises greater than 0 to equal to or less than 5 wt% of one or more compounds selected from the group consisting of pigments and antioxidants.

[0016] In an alternative embodiment, the present disclosure further provides a breathable film according to any of the preceding embodiments and a method of making the breathable film, except that the polymer composition further comprises greater than 0 to equal to or less than 10 wt% of one or more compounds selected from the group consisting of polypropylene and low density polyethylene.

[0017] In an alternative embodiment, the present disclosure further provides a breathable film according to any of the preceding embodiments and a method of making the breathable film, except that the at least one film layer comprises a polymer composition comprising 30 to 60 wt% linear low density polyethylene resin exhibiting the following various properties: (1) a CEF fraction of 70 to 90°C equal to or greater than 80% of the total CEF fraction; (2) a melt index, I2, measured according to ASTM D 1238 (2.16 kg at 190°C), equal to or greater than 2.0 g / 10 min and equal to or less than 5.0 g / 10 min; and (3) a melt flow ratio, I 10 / I2, equal to or less than 6.7.

[0018] In an alternative embodiment, this disclosure further provides a breathable membrane according to any of the foregoing embodiments and a method for preparing said breathable membrane, wherein, in addition to at least one film layer comprising a polymer composition, said polymer composition comprises (a) 45 to 55% by weight of polylinear low-density polyethylene resin exhibiting the following various properties: (1) a CEF fraction at 70 to 90°C equal to or greater than 80% of the total CEF fraction; (2) a melt flow index I2 equal to or greater than 2.0 g / 10 min and equal to or less than 5.0 g / 10 min as measured according to ASTM D 1238 (2.16 kg at 190°C); and (3) a melt flow ratio I 10 / I2 equals or is less than 6.7; and (b) 55 to 45% by weight of CaCO3.

[0019] In an alternative embodiment, this disclosure further provides a breathable membrane according to any of the foregoing embodiments and a method for preparing the breathable membrane, except that the machine orientation is performed with a stretch ratio equal to or greater than 1.5.

[0020] In an alternative embodiment, this disclosure further provides a breathable membrane according to any of the foregoing embodiments and a method for preparing the breathable membrane, except that the breathable membrane includes one or more additional membrane layers. Attached Figure Description

[0021] For the purpose of illustrating the invention, exemplary forms are shown in the accompanying drawings; however, it should be understood that the invention is not limited to the precision devices and instruments shown.

[0022] Figure 1 It is a graph illustrating the tensile properties of films formed from the inventive and comparative compositions in the machine direction, as measured according to ISO 527-3;

[0023] Figure 2 This is a graph illustrating the CEF analysis of the inventive and comparative compositions;

[0024] Figure 3 This is a diagram illustrating the puncture resistance of the membrane formed by the inventive and comparative composite compositions;

[0025] Figure 4 This is a diagram illustrating the hydrohead of the membrane formed by the invented and comparative composite compositions;

[0026] Figure 5 This is a graph illustrating the water vapor transmission rate (38°C-90%RH) properties of membranes formed from the invented and comparative composite compositions;

[0027] Figure 6 This is a graph illustrating the tensile strength properties of the films formed from the inventive and comparative composite compositions in the machine direction at 5% elongation; and

[0028] Figure 7 are graphs illustrating the shrink properties of inventive and comparative examples in the machine direction (immersed in a water bath at 80°C for 30 seconds). DETAILED DESCRIPTION

[0029] The present disclosure provides breathable films and methods of making the breathable films. The breathable films according to the present disclosure include a film layer including a polymer composition including linear low density polyethylene resin equal to or less than 60 wt% that exhibits the following properties: (1) a CEF fraction at 70 to 90°C equal to or greater than 80% of the total CEF fraction; (2) a melt index, I2, measured according to ASTM D 1238 (2.16 kg at 190°C) in the range equal to or greater than 2.0 g / 10 min and equal to or less than 5.0 g / 10 min; and (3) a melt flow ratio, I 10 / I2 equal to or less than 6.7.

[0030] The method of making a breathable film according to the present disclosure includes: (a) cast extruding a polymer composition including greater than 0 wt% to 60 wt% of linear low density polyethylene that exhibits the following properties: (1) a CEF fraction at 70 to 90°C equal to or greater than 80% of the total CEF fraction; (2) a melt index, I2, measured according to ASTM D 1238 (2.16 kg at 190°C) equal to or greater than 2.0 g / 10 min and equal to or less than 5.0 g / 10 min; and (3) a melt flow ratio, I 10 / I2 equal to or less than 6.7, to make a cast extruded film layer; and (b) machine direction orienting the cast extruded film layer.

[0031] In an alternative embodiment, the method of making a breathable film according to the present disclosure includes: (a) blow extruding a polymer composition including greater than 0 wt% to 60 wt% of linear low density polyethylene that exhibits the following properties: (1) a CEF fraction at 70 to 90°C equal to or greater than 80% of the total CEF fraction; (2) a melt index, I2, measured according to ASTM D 1238 (2.16 kg at 190°C) equal to or greater than 2.0 g / 10 min and equal to or less than 5.0 g / 10 min; and (3) a melt flow ratio, I 10 / I2 equal to or less than 6.7, to make a blown film layer; and (b) machine direction orienting the blown film layer.

[0032] The polymer composition comprises 60 wt% or less of linear low density polyethylene, described further below, based on the weight of the polymer composition, for example, 30 to 60 wt% of linear low density polyethylene, based on the weight of the polymer composition. The polymer composition comprises 40 to 60 wt% of CaC03, based on the weight of the polymer composition. The polymer composition can further comprise 10 wt% or less of low density polyethylene or polypropylene, based on the weight of the polymer composition.

[0033] The polymer composition can further comprise additional components, such as one or more additives. Such additives include, but are not limited to, antistatic agents, color enhancers, dyes, lubricants, fillers (such as Ti02), opacifiers, nucleating agents, processing aids, pigments, primary antioxidants, secondary antioxidants, processing aids, UV stabilizers, anti-block agents, slip agents, tackifiers, flame retardants, antimicrobials, odor-reducing agents, antifungal agents, and combinations thereof. The polymer composition can contain from about 0.1 to about 10% combined weight of such additives, based on the weight of the polymer composition including such additives.

[0034] Linear Low Density Polyethylene (LLDPE)

[0035] The linear low density polyethylene (LLDPE) exhibits the following various properties: (1) a CEF fraction of 70 to 90 °C equal to or greater than 80% of the total CEF fraction; (2) a melt index, I2, measured according to ASTM D 1238 (2.16 kg at 190 °C) in the range equal to or greater than 2.0 grams / 10 minutes and equal to or less than 5.0 grams / 10 minutes; and (3) a melt flow ratio, I 10 / I2 equal to or less than 6.7.

[0036] The linear low density polyethylene (LLDPE) comprises an ethylene / alpha-olefin copolymer comprising (a) less than or equal to 60 wt%, for example at least 70 wt%, or at least 80 wt%, or at least 90 wt%, of units derived from ethylene; and (b) less than 30 wt%, for example less than 25 wt%, or less than 20 wt%, or less than 10 wt%, of units derived from one or more alpha-olefin comonomers. The term “ethylene / alpha-olefin comonomer” refers to a polymer containing greater than 50 mole percent polymerized ethylene monomer (based on the total amount of polymerizable monomers) and at least one other comonomer. In a particular embodiment, the ethylene / alpha-olefin copolymer has units derived from ethylene and units derived from two different alpha-olefin comonomers.

[0037] Typically, the alpha-olefin comonomer has no more than 20 carbon atoms. For example, preferably the alpha-olefin comonomer can have 3 to 8 carbon atoms, and more preferably 3 to 6 carbon atoms. Exemplary alpha-olefin comonomers include, but are not limited to, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, and 4-methyl-1-pentene. The one or more alpha-olefin comonomers may, for example, be selected from the group consisting of propylene, 1-butene, 1-hexene, or alternatively, from the group consisting of 1-butene and 1-hexene. In one embodiment, the linear low density polyethylene resin does not contain units derived from 1-octene.

[0038] The LLDPE has a melt index, I2, measured according to ASTM D 1238 (2.16 kg at 190 °C) in the range of equal to or greater than 2.0 g / 10 min and equal to or less than 5.0 g / 10 min. All individual values and subranges from 2.0 to 5.0 g / 10 min are included and disclosed herein; for example, I2may range from a lower limit of 2.0, 3.0, or 4.0 g / 10 min to an upper limit of 3.0, 4.0, or 5.0 g / 10 min. For example, I2may be 2.0 to 5.0 g / 10 min, or alternatively, 2.0 to 3.5 g / 10 min, or alternatively, 3.5 to 5.0 g / 10 min, or alternatively, 3.0 to 4.0 g / 10 min.

[0039] The LLDPE is characterized by a zero shear viscosity ratio (ZSVR) in the range of 1.2 to 5.0. All individual values and subranges within the range of 1.2 to 5.0 are included and disclosed herein; for example, the ZSVR can range from a lower limit of 1.2, 1.4, 1.6, 1.8 to an upper limit of 2.0, 3.0, 4.0, or 5.0. For example, the ZSVR can be in the range of 1.2 to 5.0, or alternatively, 1.5 to 4, or alternatively, 1.8 to 3.5.

[0040] The LLDPE has a density in the range of 0.915 to 0.940 g / cm3, for example, 0.915 to 0.925 g / cm3. 3 , for example, 0.915 to 0.925 g / cm3. 3 All individual values and subranges from 0.915 to 0.940 g / cm3are included and disclosed herein; for example, the density can range from a lower limit of 0.915, 0.920, 0.925, 0.930, or 0.935 g / cm3to an upper limit of 0.917, 0.922, 0.927, 0.932, 0.937, or 0.940 g / cm3. For example, the density can be 0.915 to 0.940 g / cm3, or alternatively, 0.920 to 0.930 g / cm3. 3 , for example, 0.915 to 0.925 g / cm3. 3 All individual values and subranges from 0.915 to 0.940 g / cm3are included and disclosed herein; for example, the density can range from a lower limit of 0.915, 0.920, 0.925, 0.930, or 0.935 g / cm3to an upper limit of 0.917, 0.922, 0.927, 0.932, 0.937, or 0.940 g / cm3. For example, the density can be 0.915 to 0.940 g / cm3, or alternatively, 0.920 to 0.930 g / cm3. 3 , for example, 0.915 to 0.925 g / cm3. 3or alternatively, 0.915 to 0.927 g / cm 3 or alternatively, 0.927 to 0.940 g / cm 3 or alternatively, 0.915 to 0.921 g / cm 3 .

[0041] The LLDPE has a molecular weight distribution (M w / M n ) in the range of 2.0 to 3.5. All individual values and subranges from 2.0 to 3.5 are included and disclosed herein; for example, the molecular weight distribution (M w / M n ) can range from a lower limit of 2, 2.1, 2.2, 2.4, 2.5, or 2.6 to an upper limit of 2.2, 2.3, 2.4, 2.5, 2.7, 2.9, 3.2, or 3.5. For example, the molecular weight distribution (M w / M n ) can be in the range of 2.0 to 3.5, or alternatively, 2.0 to 2.4, or alternatively, 2.0 to 2.8, or alternatively, 2.8 to 3.5.

[0042] The LLDPE has a molecular weight distribution (M z / M n ) in the range of 3.5 to 6. All individual values and subranges from 3.5 to 6 are included and disclosed herein; for example, the molecular weight distribution (M z / M n ) can range from a lower limit of 3.5, 3.7, 3.9, 4.5, or 5 to an upper limit of 3.5, 4.0, 4.2, 4.4, 4.7, 5.0, 5.5, or 6.0. For example, the molecular weight distribution (M z / M n ) can be in the range of 3.5 to 6, or alternatively, 3.5 to 4.8, or alternatively, 4.8 to 6, or alternatively, 4 to 5, or alternatively, 3.5 to 4.5.

[0043] The LLDPE has a molecular weight distribution asymmetry [(M w / M n ) / (M z / M w )] i.e. M w 2 / (M n *M z ) in the range of 1.00 to 1.40. For example, the molecular weight distribution asymmetry M w 2 / (M n *M z) can range from a lower limit of 1.0, 1.05, 1.10, 1.15, or 1.20 to an upper limit of 1.25, 1.30, 1.35, or 1.40. For example, the molecular weight distribution asymmetry M w 2 / (M n *M z ) can range from 1.00 to 1.40, or alternatively, from 1.00 to 1.20, or alternatively, from 1.20 to 1.40, or alternatively, from 1.10 to 1.30.

[0044] The ethylene vinyl unsaturation of the LLDPE is less than 150 ethylene vinyl groups per million carbon atoms present in the backbone of the LLDPE. All individual values and subranges of less than 150 ethylene vinyl groups per million carbon atoms are included and disclosed herein; for example, the ethylene vinyl unsaturation can be less than 150, or alternatively, less than 120, or alternatively, less than 80, or alternatively, less than 50 ethylene vinyl groups per million carbon atoms present in the backbone of the LLDPE.

[0045] The heat of crystallization of the LLDPE is in the range of 135 to 145 J / g. All individual values and subranges of 135 to 145 J / g are included and disclosed herein; for example, the heat of crystallization can be a lower limit of 135, 136, 137, or 138 J / g to an upper limit of 140, 141, 143, or 145 J / g. For example, the heat of crystallization can be in the range of 135 to 145 J / g, or alternatively, 135 to 140 J / g, or alternatively, 140 to 145 J / g, or alternatively, 137 to 142 J / g.

[0046] The peak crystallization temperature of the LLDPE is in the range of 94 to 101 °C. All individual values and subranges of 94 to 101 °C are included and disclosed herein; for example, the peak crystallization temperature can be a lower limit of 94, 95, 96, or 97 °C to an upper limit of 98, 99, 100, or 101 °C. For example, the peak crystallization temperature can be in the range of 94 to 101 °C, or alternatively, 94 to 97 °C, or alternatively, 97 to 101 °C, or alternatively, 95 to 99 °C.

[0047] The heat of fusion of the LLDPE is in the range of 135 to 145 J / g. All individual values and subranges of 135 to 145 J / g are included and disclosed herein; for example, the heat of fusion can be a lower limit of 135, 136, 137, or 138 J / g to an upper limit of 140, 141, 143, or 145 J / g. For example, the heat of fusion can be in the range of 135 to 145 J / g, or alternatively, 135 to 140 J / g, or alternatively, 140 to 145 J / g, or alternatively, 137 to 142 J / g.

[0048] The peak melting temperature of the LLDPE is in the range of 108 to 116 °C. All individual values and subranges from 94 to 101 °C are included and disclosed herein; for example, the peak melting temperature can be from a lower limit of 108, 109, 110, or 11 °C to an upper limit of 113, 114, 115, or 116 °C. For example, the peak melting temperature can be from 108 to 116 °C, or alternatively, 108 to 112 °C, or alternatively, 112 to 116 °C, or alternatively, 110 to 114 °C.

[0049] In one embodiment, per million parts by weight of the LLDPE, the LLDPE contains less than or equal to 100 parts by weight, for example, less than 10 parts by weight, less than 8 parts by weight, less than 5 parts by weight, less than 4 parts by weight, less than 1 part by weight, less than 0.5 parts by weight, or less than 0.1 parts by weight of metal complex residues of catalyst systems comprising a polyvalent aryloxy ether metal complex. The metal complex residues of catalyst systems comprising a polyvalent aryloxy ether metal complex in the LLDPE can be measured by x-ray fluorescence (XRF), which is calibrated against reference standards. In a preferred method, the polymer resin pellets can be compression molded into about 3 / 8 inch thick plaques at elevated temperature for x-ray measurements. At very low metal complex concentrations, such as below 0.1 ppm, ICP-AES would be a suitable method to determine the metal complex residues present in the LLDPE.

[0050] The LLDPE can further comprise additional components, such as one or more other polymers and / or one or more additives. Such additives include, but are not limited to, antistatic agents, color enhancers, dyes, lubricants, fillers (such as Ti02or CaC03), opacifiers, nucleating agents, processing aids, pigments, primary antioxidants, secondary antioxidants, processing aids, UV stabilizers, anti-block agents, slip agents, tackifiers, flame retardants, antimicrobials, odor-reducing agents, antifungal agents, and combinations thereof. The LLDPE can contain from about 0.1% to about 10% combined weight of such additives, based on the weight of the LLDPE including such additives.

[0051] Any conventional solution (co)polymerization single reactor reaction process can be used to prepare the LLDPE. One method of preparing the LLDPE disclosed herein is described in detail in U.S. Patent 5,977,251, the disclosure of which is incorporated herein by reference in its entirety.

[0052] In one embodiment, the LLDPE is prepared via a polymerization process in a single solution phase loop reactor system, wherein the catalyst system comprises (a) one or more procatalysts comprising a metal ligand complex of the following formula (I):

[0053]

[0054] M is titanium, zirconium, or hafnium, each independently in the +2, +3, or +4 formal oxidation state; and n is an integer from 0 to 3, and wherein when n is 0, X is absent; and

[0055] each X is independently a neutral, monoanionic, or dianionic monodentate ligand; or two Xs are linked together to form a neutral, monoanionic, or dianionic bidentate ligand; and X and n are selected in a manner such that the metal ligand complex of formula (I) is overall neutral; and

[0056] each Z is independently O, S, N(C1-C40)hydrocarbyl, or P(C1-C40)hydrocarbyl;

[0057] L is (C2-C40)alkylene or (C2-C40)heteroalkylene, wherein (C2-C40)alkylene has a portion comprising a 2- to 10-carbon atom linking group backbone connecting the Z atoms (to which L is bonded) in formula (I), and (C2-C40)heteroalkylene has a portion comprising a 3- to 10-atom linking group backbone connecting the Z atoms in formula (I), wherein each of the 3 to 10 atoms of the 3- to 10-atom linking group backbone of (C2-C40)heteroalkylene is independently a carbon atom or a heteroatom, wherein each heteroatom is independently O, S, S(O), S(O)2, Si(R C )2, Ge(R C )2, P(RP), or N(R N ), wherein each R C is independently selected from the group consisting of (C1-C40)hydrocarbyl. As used herein, R C includes instances in which two R C groups are linked together to form a diradical ring and wherein Si is within the ring. Each RPis (C1-C40)hydrocarbyl; and each R N is (C1-C40)hydrocarbyl or absent; and

[0058] R 1-10 is each independently selected from the group consisting of (C1-C40)hydrocarbyl, (C1-C40)heterohydrocarbyl, Si(R C )3, Ge(R C )3, P(R P )2, N(R N )2, OR C , SR C , NO2, CN, CF3, R C S(O)-, R C S(O)2-, (R C )2C=N-, R C C(O)O-, RC OC(O)-, R C C(O)N(R)-, (R C )2NC(O)-, a halogen atom, a hydrogen atom, and any combination thereof, and

[0059] at least two Y1-Y3and at least two Y4-Y6are fluorine atoms, and when only two Y1-Y3and only two Y4-Y6are fluorine atoms, the non-fluorine Y1-Y6are selected from the group consisting of H atoms, alkyl groups, aryl groups, heteroaryl groups, and alkoxy groups, and

[0060] optionally, R 1-10 two or more R groups of a group (e.g., from R 1-4 , R 5-8 ) can be bound together into a ring structure, such ring structure having 2 to 50 atoms in the ring, not including any hydrogen atoms.

[0061] As used herein, the term “(C x -C y )hydrocarbon group” means a hydrocarbon radical of x to y carbon atoms, and the term “(C x -C y )hydrocarbylene group” means a hydrocarbon diradical of x to y carbon atoms, and the term “(C x -C y )alkyl group” means an alkyl group of x to y carbon atoms, and the term “(C x -C y )cycloalkyl group” means a cycloalkyl group of x to y carbon atoms.

[0062] As used herein, the term “(C1-C40)hydrocarbon group” means a hydrocarbon radical of 1 to 40 carbon atoms, and the term “(C2-C40)hydrocarbylene group” means a hydrocarbon diradical of 2 to 40 carbon atoms, wherein each hydrocarbon radical and diradical is independently aromatic (6 carbon atoms or more) or non-aromatic, saturated or unsaturated, straight-chain or branched-chain, cyclic (including monocyclic and polycyclic, fused and non-fused polycyclic, including bicyclic; 3 carbon atoms or more) or acyclic, or a combination of two or more thereof; and each hydrocarbon radical and diradical is each independently the same or different from the other hydrocarbon radical and diradical, and is independently unsubstituted or substituted with one or more R S substituents.

[0063] Preferably, the (C1-C40)hydrocarbyl groups are independently unsubstituted or substituted (C1-C40)alkyl, (C3-C40)cycloalkyl, (C3-C20)cycloalkyl-(C1-C20)alkylene, (C6-C40)aryl, or (C6-C20)aryl-(C1-C20)alkylene. More preferably, each of the foregoing (C1-C40)hydrocarbyl groups independently has up to 20 carbon atoms (i.e., (C1-C20)hydrocarbyl), and still more preferably up to 12 carbon atoms.

[0064] The terms "(C1-C40)alkyl" and "(C1-C18)alkyl" mean, respectively, a saturated straight chain or branched chain hydrocarbon radical of 1 to 40 carbon atoms or 1 to 18 carbon atoms, which is unsubstituted or substituted by one or more R s Examples of unsubstituted (C1-C40)alkyl are unsubstituted (C1-C20)alkyl; unsubstituted (C1-C10)alkyl; unsubstituted (C1-C5)alkyl; methyl; ethyl; 1-propyl; 2-propyl; 1-butyl; 2-butyl; 2-methylpropyl; 1,1-dimethylethyl; 1-pentyl; 1-hexyl; 1-heptyl; 1-nonyl; and 1-decyl. Examples of substituted (C1-C40)alkyl are substituted (C1-C20)alkyl, substituted (C1-C10)alkyl, trifluoromethyl, and (C45)alkyl. (C45)alkyl is, for example, (C27-C40)alkyl substituted by one R5, which is, respectively, (C18-C5)alkyl. Preferably, each (C1-C5)alkyl is independently methyl, trifluoromethyl, ethyl, 1-propyl, 1-methylethyl, or 1,1-dimethylethyl.

[0065] The term "(C6-C40)aryl" means an unsubstituted or substituted (by one or more R S ) mono-, bi- or tricyclic aromatic hydrocarbon radical of 6 to 40 carbon atoms, wherein at least 6 to 14 carbon atoms are aromatic ring carbon atoms, and the mono-, bi- or tricyclic radical contains 1, 2 or 3 rings, respectively; wherein 1 ring is aromatic, and 2 or 3 rings are independently fused or non-fused, and at least one of the 2 or 3 rings is aromatic. Examples of unsubstituted (C6-C40)aryl are unsubstituted (C6-C20)aryl; unsubstituted (C6-C18)aryl; 2-(C1-C5)alkyl-phenyl; 2,4-bis(C1-C5)alkyl-phenyl; phenyl; fluorenyl; tetrahydrofluorenyl; indacenyl; hexahydroindacenyl; indenyl; dihydroindenyl; naphthyl; tetrahydronaphthyl; and phenanthrene. Examples of substituted (C6-C40)aryl are substituted (C6-C20)aryl; substituted (C6-C18)aryl; 2,4-bis[(C20)alkyl]-phenyl; polyfluorophenyl; pentafluorophenyl; and fluoren-9-one-1-yl.

[0066] The term "(C3-C40)cycloalkyl" means a saturated cyclic hydrocarbon radical of 3 to 40 carbon atoms, which is unsubstituted or substituted by one or more R s . Other cycloalkyl groups (e.g., (C3-C12)cycloalkyl) are defined in a similar manner. Examples of unsubstituted (C3-C40)cycloalkyl are unsubstituted (C3-C20)cycloalkyl, unsubstituted (C3-C10)cycloalkyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, and cyclodecyl. Examples of substituted (C3-C40)cycloalkyl are substituted (C3-C20)cycloalkyl, substituted (C3-C10)cycloalkyl, cyclopentan-2-yl, and 1-fluorocyclohexyl.

[0067] Examples of (C1-C40)alkylene are unsubstituted or substituted (C6-C40)arylene, (C3-C40)cycloalkylene, and (C1-C40)alkylene (e.g., (C1-C20)alkylene). In some embodiments, the biradical is on the same carbon atom (e.g., -CH2-) or on adjacent carbon atoms (i.e., 1,2-biradical), or is separated by one, two, or more intervening carbon atoms (e.g., corresponding 1,3-biradical, 1,4-biradical, etc.). Preferred are 1,2-, 1,3-, 1,4-, or a,ω-biradicals, and more preferably 1,2-biradicals. a,ω-biradicals are biradicals with the largest carbon main chain separation between the radical carbons. More preferably (C6-C18)arylene, (C3-C20)cycloalkylene, or (C2-C20)alkylene in the form of a 1,2-biradical, 1,3-biradical, or 1,4-biradical.

[0068] The term "(C3-C40)cycloalkylene" means a cyclic biradical of 3 to 40 carbon atoms (i.e., the radicals are on ring atoms), which is unsubstituted or substituted by one or more R s . Examples of unsubstituted (C3-C40)cycloalkylene are 1,3-cyclopropylene, 1,1-cyclopropylene, and 1,2-cyclohexylene. Examples of substituted (C3-C40)cycloalkylene are 2-oxo-1,3-cyclopropylene and 1,2-dimethyl-1,2-cyclohexylene.

[0069] The term "(C1-C40)heteroalkyl" means a heteroalkyl radical of 1 to 40 carbon atoms, and the term "(C1-C40)heteroalkylene" means a heteroalkyl biradical of 1 to 40 carbon atoms, and each heteroalkyl independently has one or more heteroatoms O; S; S(O); S(O)2; Si(R C )2; Ge(R C )2; P(R P ), and N(R N ), wherein each R Cindependently unsubstituted (C1-C40)hydrocarbyl, each R P is unsubstituted (C1-C40)hydrocarbyl; and each R N is unsubstituted (C1-C40)hydrocarbyl or is absent (e.g., when N comprises -N= or a three carbon substituted N). The heterohydrocarbyl radical and each heterohydrocarbyl biradical are independently on a carbon atom or a heteroatom thereof, but preferably on a carbon atom when bonded to a heteroatom in Formula (I) or to a heteroatom of another heterohydrocarbyl or heterohydrocarbylene group. Each (C1-C40)heterohydrocarbyl and (C1-C40)heterohydrocarbylene is independently unsubstituted or substituted (by one or more R s ), aromatic or nonaromatic, saturated or unsaturated, straight-chain or branched, cyclic (including monocyclic and polycyclic, fused and non-fused polycyclic) or acyclic, or a combination of two or more thereof; and each is the same or different from the other.

[0070] Preferably, the (C1-C40)heterohydrocarbyl is independently unsubstituted or substituted (C1-C40)heteroalkyl, (C1-C40)hydrocarbyl-O-, (C1-C40)hydrocarbyl-S-, (C1-C40)hydrocarbyl-S(O)-, (C1-C40)hydrocarbyl-S(O)2-, (C1-C40)hydrocarbyl-Si(R C )2-, (C1-C40)hydrocarbyl-Ge(R C )2-, (C1-C40)hydrocarbyl-N(R N )-, (C1-C40)hydrocarbyl-P(R P )-, (C2-C40)heterocycloalkyl, (C2-C19)heterocycloalkyl-(C1-C20)alkylene, (C3-C20)cycloalkyl-(C1-C19)heteroalkylene, (C2-C19)heterocycloalkyl-(C1-C20)heteroalkylene, (C1-C40)heteroaryl, (C1-C19)heteroaryl-(C1-C20)alkylene, (C6-C20)aryl-(C1-C19)heteroalkylene, or (C1-C19)heteroaryl-(C1-C20)heteroalkylene. The term “(C1-C40)heteroaryl” means from 1 to 40 total carbon atoms and from 1 to 4 heteroatoms, unsubstituted or substituted (by one or more R S) mono-, bi- or tri-cyclic heteroaromatic radical, and the mono-, bi- or tri-cyclic radical comprises 1, 2 or 3 rings, respectively, wherein the 2 or 3 rings are independently fused or non-fused, and at least one of the 2 or 3 rings is heteroaromatic. Other heteroaryl groups (e.g., (C4-C12)heteroaryl) are defined in a similar manner. Mono-cyclic heteroaromatic radicals are 5- or 6-membered rings. A 5-membered ring has 1 to 4 carbon atoms and 4 to 1 heteroatoms, each heteroatom being O, S, N or P, and preferably O, S or N, respectively. Examples of 5-membered ring heteroaromatic radicals are pyrrol-1-yl; pyrrol-2-yl; furan-3-yl; thiophen-2-yl; pyrazol-1-yl; isoxazol-2-yl; isothiazol-5-yl; imidazol-2-yl; oxazol-4-yl; thiazol-2-yl; 1,2,4-triazol-1-yl; 1,3,4-oxadiazol-2-yl; 1,3,4-thiadiazol-2-yl; tetrazol-1-yl; tetrazol-2-yl; and tetrazol-5-yl. A 6-membered ring has 4 or 5 carbon atoms and 2 or 1 heteroatoms, the heteroatoms being N or P, and preferably N. Examples of 6-membered ring heteroaromatic radicals are pyridin-2-yl; pyrimidin-2-yl; and pyrazin-2-yl. Bi-cyclic heteroaromatic radicals are preferably fused 5,6- or 6,6-ring systems. Examples of fused 5,6-ring system bi-cyclic heteroaromatic radicals are indol-1-yl; and benzimidazol-1-yl. Examples of fused 6,6-ring system bi-cyclic heteroaromatic radicals are quinolin-2-yl; and isoquinolin-1-yl. Preferably, tri-cyclic heteroaromatic radicals are fused 5,6,5-; 5,6,6-; 6,5,6-; or 6,6,6-ring systems. An example of a fused 5,6,5-ring system is 1,7-dihydropyrrolo[3,2-f]indol-1-yl. An example of a fused 5,6,6-ring system is 1H-benzo[f]indol-1-yl. An example of a fused 6,5,6-ring system is 9H-carbazol-9-yl. An example of a fused 6,6,6-ring system is acridin-9-yl.

[0071] In some embodiments, the (C1-C40)heteroaryl is 2,7-disubstituted carbazolyl or 3,6-disubstituted carbazolyl or unsubstituted carbazole, more preferably wherein each R s independently is phenyl, methyl, ethyl, isopropyl or t-butyl, still more preferably 2,7-di(t-butyl)-carbazolyl, 3,6-di(t-butyl)-carbazolyl, 2,7-di(t-octyl)-carbazolyl, 3,6-di(t-octyl)-carbazolyl, 2,7-diphenylcarbazolyl, 3,6-diphenylcarbazolyl, 2,7-bis(2,4,6-trimethylphenyl)-carbazolyl or 3,6-bis(2,4,6-trimethylphenyl)-carbazolyl.

[0072] The aforementioned heteroalkyl and heteroalkylene groups are saturated straight-chain or branched radicals or diradicals, containing (C1-C40) carbon atoms, or, as the case can be, fewer carbon atoms, and one or more heteroatoms Si(R C )2, Ge(R C )2, P(R P ), N(R N ), N, O, S, S(O) and S(O)2, wherein each of the heteroalkyl and heteroalkylene groups independently is unsubstituted or substituted by one or more R S .

[0073] Examples of unsubstituted (C2-C40)heterocycloalkyl are unsubstituted (C2-C20)heterocycloalkyl, unsubstituted (C2-C10)heterocycloalkyl, aziridin-1-yl, oxetan-2-yl, tetrahydrofuran-3-yl, pyrrolidin-1-yl, tetrahydrothiophen-S,S-dioxide-2-yl, morpholin-4-yl, 1,4-dioxan-2-yl, hexahydroazepin-4-yl, 3-oxa-cyclooctyl, 5-thia-cyclononyl and 2-aza-cyclodecyl.

[0074] The term "halogen atom" means a fluorine atom (F), a chlorine atom (CI), a bromine atom (Br) or an iodine atom (I) radical. Preferably each halogen atom is independently a Br, F or CI radical, and more preferably a F or CI radical. The term "halide" means a fluoride (F-), a chloride (CI-), a bromide (Br-) or an iodide (I-) anion.

[0075] Unless indicated otherwise herein, the term "heteroatom" means O, S, S(O), S(O)2, Si(R C )2, Ge(R C )2, P(RP) or N(R N ), wherein independently each R C is unsubstituted (C1-C40)hydrocarbyl, each RPis unsubstituted (C1-C40)hydrocarbyl; and each R N is unsubstituted (C1-C40)hydrocarbyl or is absent (absent when N comprises -N=). Preferably, in the metal ligand complex of formula (I), there are no O-O, S-S or O-S bonds, except for the O-S bond in the S(O) or S(O)2diradical function. More preferably, in the metal ligand complex of formula (I), there are no O-O, N-N, P-P, N-P, S-S or O-S bonds, except for the O-S bond in the S(O) or S(O)2diradical function.

[0076] Preferably, in the metal ligand complex of formula (I), there are no O-O, S-S, or O-S bonds in addition to the O-S bond in the S(O) or S(O)2 diradical functionality. More preferably, in the metal ligand complex of formula (I), there are no O-O, N-N, P-P, N-P, S-S, or O-S bonds in addition to the O-S bond in the S(O) or S(O)2 diradical functionality.

[0077] The term "saturated" means the absence of carbon-carbon double bonds, carbon-carbon triple bonds, and (in heteroatom-containing groups) carbon-nitrogen, carbon-phosphorus, and carbon-silicon double or triple bonds. When a saturated chemical group is substituted by one or more substituents R S When substituted, the optional substituents R S may or can not contain one or more double and / or triple bonds. The term "unsaturated" means containing one or more carbon-carbon double bonds, carbon-carbon triple bonds, and (in heteroatom-containing groups) carbon-nitrogen, carbon-phosphorus, and carbon-silicon double or triple bonds, excluding any such double bonds that can be present in the (hetero)aromatic ring (if any) or in the substituents R S (if any) or (hetero)aromatic ring (if any). The term "heteroatom" means an atom of any element other than carbon or hydrogen. In some embodiments, the heteroatom is nitrogen, oxygen, or sulfur. In some embodiments, the heteroatom is nitrogen or oxygen. In some embodiments, the heteroatom is nitrogen.

[0078] M is titanium, zirconium, or hafnium. In one embodiment, M is zirconium or hafnium, and in another embodiment, M is hafnium. In some embodiments, M is in the +2, +3, or +4 formal oxidation state. In some embodiments, n is 0, 1, 2, or 3. Each X is independently a neutral, monoanionic, or dianionic monodentate ligand; or two Xs are linked together to form a neutral, monoanionic, or dianionic bidentate ligand. X and n are selected in a manner such that the metal ligand complex of formula (I) is overall neutral. In some embodiments, each X is independently a monodentate ligand. In one embodiment, when there are two or more X monodentate ligands, each X is the same. In some embodiments, the monodentate ligand is a monoanionic ligand. The net formal oxidation state of the monoanionic ligand is -1. Each monoanionic ligand can independently be hydride, (C1-C40)hydrocarbyl carbanion, (C1-C40)heterohydrocarbyl carbanion, halide, nitrate, carbonate, phosphate, sulfate, HC(O)O-, (C1-C40)hydrocarbyl C(O)O-, HC(O)N(H)-, (C1-C40)hydrocarbyl C(O)N(H)-, (C1-C40)hydrocarbyl C(O)N((C1-C20)hydrocarbyl)-, R K R L B-, R K R L N-, R K O-, R K S-, R K R L p-, or R M R K R LSi-, wherein each R K , R L , and R M are independently hydrogen, (Ci-C4o)hydrocarbyl, or (Ci-C4o)heterohydrocarbyl, or R K and R L are joined together to form a (C2-C4o)hydrocarbylene or (Ci-C4o)heterohydrocarbylene and R M are as defined above.

[0079] Co-catalyst component

[0080] In some embodiments, the procatalyst comprising the metal ligand complex of formula (I) can be rendered catalytically active by contacting it with an activating co-catalyst or combination or by using activating techniques as known in the art for metal-based olefin polymerization reactions. Suitable activating co-catalysts for use herein include alkylaluminums; polymeric or oligomeric aluminoxanes (also known as aluminoxanes); neutral Lewis acids; and non-polymeric, non-coordinating, ion-forming compounds including the use of such compounds under oxidizing conditions. A suitable activating technique is bulk electrolysis. Combinations of one or more of the foregoing activating co-catalysts and techniques are also contemplated. The term "alkylaluminum" means a monoalkylaluminum dihydride or monoalkylaluminum dihalide, a dialkylaluminum hydride or dialkylaluminum halide, or a trialkylaluminum. Aluminoxanes and their preparation are known, for example, in United States Patent Number (USPN) US 6,103,657. Examples of preferred polymeric or oligomeric aluminoxanes are methylaluminoxane, triisobutylaluminum-modified methylaluminoxane, and isobutylaluminoxane.

[0081] Exemplary Lewis acid activators are Group 13 metal compounds containing 1 to 3 hydrocarbyl substituents as described herein. In some embodiments, exemplary Group 13 metal compounds are tri(hydrocarbyl)- substituted aluminums or tri(hydrocarbyl)-boron compounds. In some other embodiments, exemplary Group 13 metal compounds are tri(hydrocarbyl)-substituted aluminums or tri(hydrocarbyl)-boron compounds are tri((Ci-Cio)alkyl)aluminums or tri((C6-Ci8)aryl)boron compounds and halogenated (including perhalogenated) derivatives thereof. In some other embodiments, exemplary Group 13 metal compounds are tri(fluoro-substituted phenyl)boranes, in other embodiments, tri(pentafluorophenyl)borane. In some embodiments, the activating co-catalyst is a tri((Ci-C2o)hydrocarbyl)borate (e.g., trityl tetrafluoroborate) or a tri((Ci-C2o)hydrocarbyl)ammonium tetra((Ci-C2o)hydrocarbyl)borane (e.g., bis(octadecyl)methylammonium tetra(pentafluorophenyl)borane). As used herein, the term "ammonium" means a nitrogen cation which is ((Ci-C2o)hydrocarbyl)4N+, ((Ci-C2o)hydrocarbyl)3N(H)+, ((Ci-C2o)hydrocarbyl)2N(H)2+, (Ci-C2o)hydrocarbylN(H)3+, or N(H)4+, wherein each (Ci-C2o)hydrocarbyl group can be the same or different.

[0082] Exemplary combinations of neutral Lewis acid activator co-catalysts include mixtures comprising a combination of tri((Ci-C4)alkyl)aluminum and a halogenated tri((C6-Ci8)aryl)boron compound, particularly tri(pentafluorophenyl)borane. Other exemplary embodiments are combinations of such neutral Lewis acid mixtures with polymeric or oligomeric aluminoxanes, as well as combinations of a single neutral Lewis acid, particularly tri(pentafluorophenyl)borane, with polymeric or oligomeric aluminoxanes. Exemplary embodiments have a molar ratio of ((metal ligand complex):(tri(pentafluorophenylborane):(aluminoxane) [e.g., (Group 4 metal ligand complex):(tri(pentafluorophenylborane):(aluminoxane)] of 1 : 1 : 1 to 1 : 10 : 30, other exemplary embodiments are 1 : 1 : 1.5 to 1 : 5 : 10.

[0083] Many activating cocatalysts and activation techniques have been previously taught in the following U.S. patents with respect to different metal ligand complexes: US 5,064,802; US 5,153,157; US 5,296,433; US 5,321,106; US 5,350,723; US 5,425,872; US 5,625,087; US 5,721,185; US 5,783,512; US 5,883,204; US 5,919,983; US 6,696,379; and US 7,163,907. Examples of suitable hydrocarbyloxides are disclosed in US 5,296,433. Examples of Bronsted acid salts suitable for use in addition polymerization catalysts are disclosed in US 5,064,802; US 5,919,983; US 5,783,512. Examples of salts of cationic oxidants and non-coordinating anion compatible with addition polymerization catalysts as activating cocatalysts are disclosed in US 5,321,106. Examples of carbonium salts suitable for use in addition polymerization catalysts as activating cocatalysts are disclosed in US 5,350,723. Examples of silylium salts suitable for use in addition polymerization catalysts as activating cocatalysts are disclosed in US 5,625,087. Examples of complexes of suitable alcohols, thiols, silanols, and oximes with tris(pentafluorophenyl)borane are disclosed in US 5,296,433. Some of these catalysts are also described in a portion of US 6,515,155 Bl beginning at column 50, line 39 and continuing through column 56, line 55, only this portion of which is incorporated herein by reference.

[0084] In some embodiments, the procatalyst comprising the metal ligand complex of formula (I) can be activated to form an activated catalyst composition by combination with one or more cocatalysts, such as a cation-forming cocatalyst, a strong Lewis acid, or a combination thereof. Suitable cocatalysts include polymeric or oligomeric aluminoxanes, particularly methyl aluminoxane, and inert compatible non-coordinating ion-forming compounds. Exemplary suitable cocatalysts include, but are not limited to, modified methyl aluminoxane (MMAO), bis(hydrogenated tallowalkyl)methyl, tetra(pentafluorophenyl)borate(1-)amine, triethyl aluminum (TEA), and any combination thereof.

[0085] In some embodiments, one or more of the foregoing activating cocatalysts are used in combination with one another. A particularly preferred combination is a mixture of a tri((Ci-C4)hydrocarbyl)aluminum, a tri((Ci-C4)hydrocarbyl)borane or ammonium borate with an oligomeric or polymeric aluminoxane compound.

[0086] The ratio of the total molar number of one or more metal ligand complexes of formula (I) to the total molar number of one or more activation cocatalysts is 1:10,000 to 100:1. In some embodiments, the ratio is at least 1:5000, in some other embodiments at least 1:1000; and 10:1 or less, and in some other embodiments 1:1 or less. When aluminoxane is used alone as an activation cocatalyst, the molar number of aluminoxane used is preferably at least 100 times the molar number of the metal ligand complexes of formula (I). When tris(pentafluorophenyl)borane is used alone as an activation cocatalyst, in some other embodiments the molar number of tris(pentafluorophenyl)borane used is 0.5:1 to 10:1 to the total molar number of one or more metal ligand complexes of formula (I), in some other embodiments 1:1 to 6:1, and in some other embodiments 1:1 to 5:1. The remaining activation cocatalyst is typically used in a molar amount approximately equal to the total molar amount of the metal ligand complexes of formula (I).

[0087] End use application

[0088] The LLDPE according to this disclosure is suitable for cast film extrusion processes or blown film extrusion processes, wherein the film is further oriented at least in the machine direction. The LLDPE according to this disclosure can be extruded in pure form or as a blend with other polymers, additives, and fillers. The film can be a single-layer or co-extruded multilayer film obtained through various extrusions using single or multiple dies. The resulting film can be used as is or laminated onto other films or substrates, for example, by thermal adhesive lamination or direct extrusion onto a substrate. The resulting film and laminated articles can undergo other forming operations, such as embossing, stretching, and thermoforming. Surface treatments such as corona treatment can be applied, and the film can be printed.

[0089] The membranes prepared from LLDPE according to this disclosure exhibit a steep stretching machine direction (MD) curve, which in turn results in excellent stretchability during machine direction orientation (MDO) activation. The stretch ratio of the membranes prepared from LLDPE according to this disclosure during machine direction orientation can be at least 1.5X, for example, 2X to 6X, or alternatively 2X to 5.5X, or alternatively 2X to 5X, or alternatively from 2X to 4.5X.

[0090] The basis weight of the breathable film according to the present application is in the range of 5 to 25 gsm. All individual values and subranges from 5 to 25 gsm are included and disclosed herein; for example, the basis weight of the film can be in the range from a lower limit of 5, 8, 11, 14, 17, 20, or 23 gsm to an upper limit of 6, 9, 12, 15, 18, 21, or 25 gsm. For example, the basis weight of the film can be in the range of 5 to 25 gsm, or alternatively, 5 to 15, or alternatively, 15 to 25 gsm, or alternatively, 10 to 20 gsm, or alternatively, from 10 to 23 gsm.

[0091] The water vapor transmission rate of the breathable film according to the present application is in the range of 1,000 to 9.000 grams per square meter per day (g / m2-day), measured at 38°C. All individual values and subranges from 1,000 to 9,000 g / m2-day are included and disclosed herein; for example, the water vapor transmission rate can be in the range from a lower limit of 1,000, 3,000, or 5,000 g / m2-day to an upper limit of 2,000, 5000, 8,000, or 9,000 g / m2-day. For example, the water vapor transmission rate can be in the range of 1,000 to 9,000 g / m2-day, or alternatively, 1,000 to 5,000 g / m2-day, or alternatively, 5,000 to 9,000 g / m2-day, or alternatively, 3,000 to 7,000 g / m2-day.

[0092] The films and laminates prepared from the inventive compositions can be used for various purposes, such as food packaging. The films are also suitable for hygiene and medical applications, such as breathable films for diapers, adult incontinence products, feminine hygiene products, bed pads, animal training products, and animal incontinence products.

[0093] Examples

[0094] The following examples illustrate the present application but are not intended to limit the scope of the application. The examples of the present application demonstrate that the selection of the LLDPE of the present disclosure results in superior performance during machine direction orientation, i.e., very low “minimum stretch ratio”, while maintaining acceptable final film properties, such as water vapor transmission rate (WVTR), shrinkage, and puncture strength even at low stretch ratios.

[0095] Comparative Composition 1 is DOWLEX 2107G, a non-uniformly branched ethylene-octene copolymer having a melt index (I2) of about 2.3 g / 10 min, a CEF fraction of 48.6% at 70 to 90°C, an I10 / I2 of 8.5, and a density of 0.917 g / cm3, commercially available from The Dow Chemical Company. 10 / I2 of 8.5 and a density of 0.917 g / cm3, commercially available from The Dow Chemical Company. 3 , commercially available from The Dow Chemical Company.

[0096] Comparative Composition 2 is EXCEED® EXCEED 3518, an ethylene-hexene copolymer prepared via a gas phase polymerization process in the presence of a metallocene catalyst system having a melt index (I2) of 3.5 g / 10 min, a CEF fraction of 74.5% at 70 to 90 °C, I 10 / I2of 5.8 and a density of 0.918 g / cm 3 , available from ExxonMobil Chemical Company.

[0097] Inventive Composition 1 is an ethylene-hexene copolymer having a melt index (I2) of 3.2 g / 10 min, a CEF fraction of 91.9% at 70 to 90 °C, I 10 / I2of 6.5 and a density of 0.918 g / cm 3 Inventive Composition 1 was prepared via solution polymerization in the presence of a catalyst system comprising a procatalyst represented by the formula:

[0098]

[0099] The polymerization conditions for Inventive Composition 1 are reported in Tables 1 and 2. With reference to Tables 1 and 2, TEA is triethylaluminum and PETROSOL D 100 / 120 is a solvent, which is commercially available from PETROQUIMICA DE GALICIA, S.A.U., Madrid, Spain. The properties of Inventive Composition 1 and Comparative Compositions 1 and 2 were measured and reported in Tables 3-6.

[0100] Table 1

[0101]

[0102] Table 2

[0103] Inventive composition 1 3. Catalyst Reactor co-catalyst-1 / catalyst molar feed ratio 3.0 Reactor co-catalyst-1 type Bis(hydrogenated tallow alkyl)methyl, tetra(pentafluorophenyl)borate (1-)amine Reactor co-catalyst-2 / catalyst molar ratio 33 Reactor co-catalyst-2 type TEA

[0104] Table 3

[0105]

[0106] Table 4

[0107] M w (g / mol)]]> ZSV (Pas) ZSVR Inventive composition 1 75000 2820 1.98 Comparative composition 2 77100 2050 1.30 Comparative composition 1 87100 4190 1.70

[0108] Table 5

[0109] M n (g / mol)]]> M w (g / mol)]]> M z (g / mol)]]> M w / M n ]]> M z / M w ]]> Inventive composition 1 34300 75000 136000 2.19 1.81 Comparative composition 2 31000 77100 137000 2.49 1.77 Comparative composition 1 21600 87100 327000 4.03 3.75

[0110] Table 6

[0111] Crystallization heat (g / mol) Peak crystallization temperature (°C) Melting heat (g / mol) Peak melting temperature (°C) Inventive composition 1 139.7 97.1 139.7 112.3 Comparative composition 2 145.6 101.1 145.1 113.8 Comparative composition 1 140.7 107.1 140.3 123.3 ​

[0112] Inventive composition 1 and comparative compositions 1 and 2 were extruded on a Collin cast production line to form monolayer films according to the process conditions shown in Table 7. The films are referred to herein in the manner of the composition from which the film was formed.

[0113] Table 7

[0114] Die gap (mm): 0.8 Linear speed [m / min]: 7.5 Melt temperature (°C): 215 Output rate (Kg / h): 5 Thickness (pm): 50

[0115] The properties of the films based on inventive composition 1 and comparative compositions 1 and 2 were measured and reported in Figure 1 and 2 . Referring to Figure 1 , the tensile curves clearly indicate that the film prepared from inventive composition 1 reaches the strain hardening region more quickly than the films prepared from comparative compositions 1 and 2. The ratio of the tension at 200 mm elongation to the tension at 75 mm elongation is defined herein as the hardening rate. The hardening ratios for the film prepared from inventive composition 1 and the films prepared from comparative compositions 1 and 2 are given in Table 8.

[0116] Table 8 - Hardening Rate

[0117] Comparative composition 1 = 1.08 Comparative composition 2 = 1.08 Inventive composition 1 = 1.22

[0118] Inventive composition 1 and comparative compositions 1 and 2 were further compounded via a Buss compounder to include 50 wt% CaCC. Each of the resulting compounds, inventive compound composition 1, comparative compound composition 1, and comparative compound composition 2, were dried at 60 °C for six hours, respectively, and then loaded into aluminum bags to avoid picking up moisture prior to extrusion.

[0119] Inventive compound composition 1, comparative compound composition 1, and comparative compound composition 2 were extruded via a Collin cast extrusion production line equipped with a machine direction orientation (MDO) stretching unit, with a target basis weight of 18 GSM. The compounds were fed into a hopper and extruded through a cast die into a thin film. The film was then stretched in the MDO unit by heated rollers running at different speeds. The apparatus allowed for stretching the film and subsequent annealing of the film.

[0120] Stretch calculation is the ratio between the final speed (winder) and the entry roll speed of the MDO unit.

[0121] The process settings during extrusion and stretching were as shown in Table 9:

[0122] Table 9

[0123] Melt temperature: 225 °C (feed zone 45 °C, first zone 190 °C, second zone 210 °C, all other zones: 230 °C) Die gap: 0.75 mm 42 micron filter Extruder RPM 35 Chill roll at 45 °C Stretch at 60 °C, introduce and anneal roll at 40 °C

[0124] For Comparative Composite 1, the draw ratio was increased until tiger stripes disappeared and the film had a visually uniform appearance. The draw ratio at which the tiger stripes disappeared was called the "Comparative Composite 1 Minimum Draw Ratio". At that draw ratio, the target basis weight of 18 GSM was achieved by adjusting the speed at the entry roll of the MDO unit and a film sample was taken.

[0125] Comparative Composite 2 was then run. The "Comparative Composite 2 Minimum Draw Ratio" was similar to the "Comparative Composite 1 Minimum Draw Ratio". A film sample was taken.

[0126] Inventive Composite 1 was then run. The "Inventive Composite 1 Minimum Draw Ratio" was significantly lower than the "Comparative Composite 2 Minimum Draw Ratio". A film sample was taken.

[0127] The draw ratio was then increased until the value of the "Comparative Composite 2 Minimum Draw Ratio" was reached and a second film sample was taken.

[0128] The draw ratios are reported in Table 10.

[0129] Table 10

[0130]

[0131] The properties of the four film samples shown in Table 4, obtained as above, were measured as shown in Figures 3-6

[0132] The Elongation at Break Tensile in CD was measured for each of the four film samples shown in Table 4 and the results are given in Table 11.

[0133] Table 11

[0134] Tensile elongation at break CD Comparative composite composition 1 / SR 5 503％ Comparative composite composition 2 / SR 5.2 496％ Inventive composite composition 1 / SR 5.2 481％ Inventive composite composition 1 / SR 2.8 499％

[0135] Referring to Figure 3 , the difference between the values corresponds to the window of properties that can be obtained with Inventive Composite 1 in a draw range of 2.8x to 5.2x. At the same draw ratios, Inventive Compound 1 and Comparative Compounds 1 and 2 fall in the same range of puncture resistance.

[0136] Referring to Figure 4 , a wide range of head values can be obtained with the Inventive Compound. Comparing Inventive Composite 1 with Comparative Compounds 1 and 2 at the same draw ratios shows the superiority of Inventive Composite 1.

[0137] Referring to Figure 5 ​Within the tested stretch ratio, the WVTR window of the inventive composite composition 1 is relatively narrow, meaning that an acceptable WVTR value can be obtained even at a low stretch ratio. At the same stretch ratio, the WVTR of the inventive composite composition 1 is slightly higher than that of the comparative composite composition 1, and is within the same range as that of the comparative composite composition 2 (difference < 5%).

[0138] refer to Figure 6 A comparison between configurations stretched at the same level shows that the inventive composite composition 1 outperforms the comparative composite compositions 1 and 2.

[0139] Surprisingly, reference Figure 7 The shrinkage rate of the inventive composite composition 1 appears to be independent of the stretch ratio. At the same stretch ratio, the shrinkage rate of the inventive composite composition 1 is better than that of the comparative composite composition 1 and relatively close to that of the comparative composite composition 2.

[0140] Test methods

[0141] The testing methods include the following:

[0142] Melt Flow Index

[0143] Melt flow index (I2 and I3) was measured at 190°C under loads of 2.16 kg and 10 kg, respectively, according to ASTM D-1238. 10 Its value is reported in grams per 10 minutes.

[0144] density

[0145] Samples for density measurement were prepared according to ASTM D4703. Measurements were performed within one hour of pressing the samples using ASTM D792, Method B.

[0146] High-temperature gel permeation chromatography

[0147] A Gel Permeation Chromatography (GPC) system is composed of a Waters (Milford, Mass) 150C High Temperature Chromatograph equipped with onboard differential refractometer (RI) (other suitable concentration detectors can include an IR4 infrared detector from Polymer ChAR (Valencia, Spain)). Other suitable high temperature GPC instruments include a Polymer Laboratories (Shropshire, UK) Model 210 and a Model 220. Data collection is performed using a Viscotek TriSEC software, versions 3 and 4 channel Viscotek data manager DM400. The system is also equipped with an online solvent degassing device from Polymer Laboratories (Shropshire, UK).

[0148] Suitable high temperature GPC columns can be used, such as four 30 em long Shodex HT803 13 micron columns or four 30 cm Polymer Laboratories columns of 20 micron mixed-pore-size packing (MixA LS, Polymer Laboratories). The sample carousel compartment is operated at 140 °C and the column compartment is operated at 150 °C. The samples are prepared at a concentration of 0.1 grams of polymer in 50 milliliters of solvent. The chromatographic solvent and the sample preparation solvent are each made up to contain 200 ppm of trichlorobenzene (TCB). Both solvents are sparged with nitrogen. The polyethylene sample is gently stirred at 160 °C for four hours. The injection volume is 200 microliters. The flow rate through the GPC is set at 1 ml / minute.

[0149] The GPC column set was calibrated by running 21 narrow molecular weight distribution polystyrene (PS) standards. The molecular weight (MW) of the standards ranged from 580 to 8,400,000, and the standards were contained in 6 "cocktail" mixtures. The interval between individual molecular weights for each standard mixture was at least a decade. The standards were purchased from Polymer Laboratories. The polystyrene standards were prepared at 0.025 g in 50 mL of solvent for molecular weights equal to or greater than 1,000,000, and 0.05 g in 50 mL of solvent for molecular weights less than 1,000,000. The polystyrene standards were dissolved at 80 °C with gentle agitation for 30 minutes. The narrow standards mixtures were run first and in decreasing order of the highest molecular weight component to minimize degradation. The polystyrene standard peak molecular weights were converted to polyethylene molecular weights using the following equation (as described in Williams and Ward, J. Polym. Sci., Polym. Letters, 6, 621 (1968)):

[0150] M 聚乙烯 = A x (M 聚苯乙烯 ) B ,

[0151] where M is the molecular weight of either polyethylene or polystyrene (as labeled), and B equals 1.0. A is known to those of ordinary skill in the art to range from about 0.38 to about 0.44, and is determined when calibrating with broad polyethylene standards. Molecular weight values, such as molecular weight distribution (MWD or M w / M n ), and related statistics (generally referring to conventional GPC or cc-GPC results) are defined herein as the Improved Williams and Ward Method.

[0152] DSC Crystallinity

[0153] Differential scanning calorimetry (DSC) can be used to measure the melting and crystallization behavior of polymers over a wide temperature range. For example, this analysis can be performed using a TA Instruments Q1000DSC equipped with an RCS (refrigerated cooling system) and an autosampler. During testing, a nitrogen purge gas flow of 50 mL / min is used. Each sample is melted and pressed into a thin film at approximately 175°C; the molten sample is then cooled to room temperature (approximately 25°C). A 3–10 mg sample with a diameter of 6 mm is drawn from the cooled polymer, weighed, placed in a light aluminum pan (approximately 50 mg), and the pan is shut off. The analysis is then performed to determine its thermal properties.

[0154] The thermal behavior of the sample was determined by slowly raising and lowering the sample temperature to generate a heat flow versus temperature profile. First, the sample was rapidly heated to 180°C and held isothermally for 3 minutes to remove its thermal history. Next, the sample was cooled to -40°C at a cooling rate of 10°C / min and held isothermally at -40°C for 3 minutes. Then, the sample was heated to 150°C at a heating rate of 10°C / min (this is the "second heating" slow change). The cooling and second heating profiles were recorded. The cooling profile was analyzed by setting the baseline endpoint from the start of crystallization to -20°C. The heating profile was analyzed by setting the baseline endpoint from -20°C to the end of melting. The measured value is the peak melting temperature (T0). m ), peak recrystallization temperature (T) p ), heat of fusion (H) f (in joules per gram) and the % crystallinity of the polyethylene sample calculated using the following equation:

[0155] % Crystallinity = ((Hf) / (292J / g)) × 100.

[0156] Heat of fusion (H) f The peak melting temperature is reported from the second heating profile. The peak recrystallization temperature is determined as T from the cooling profile. p .

[0157] Crystallization Elution Fractionation (CEF) Method

[0158] Crystallization-elution fractionation (CEF) was performed according to the method described in Monrabal et al., Macromolecular Symposium 257, 71-79 (2007), which is incorporated herein by reference. The CEF instrument was equipped with an IR-4 detector (such as those commercially available from PolymerChar, Spain) and a dual-angle light scattering detector model 2040 (such as those commercially available from Precision Detectors). The IR-4 detector was operated in combined mode with two filters: C006 and B057. A 10-micron guard column (such as those commercially available from PolymerLab, 50 mm × 4.6 mm) was mounted in front of the IR-4 detector in the detector oven. Ortho-dichlorobenzene (ODCB, 99% anhydrous) and 2,5-di-tert-butyl-4-methylphenol (BHT) (such as those commercially available from Sigma-Aldrich) were obtained. Silica gel 40 (particle size 0.2–0.5 mm) was also obtained (commercially available from EMD Chemicals). Before use, the silica gel was dried in a vacuum oven at 160°C for approximately two hours. Eight hundred mg of BHT and five g of silica gel were added to two liters of ODCB. ODCB containing BHT and silica gel is referred to below as "ODCB-m". ODCB-m was bubbled with dry nitrogen (N2) for one hour before use. The nitrogen was passed over CaCO3 at <90 psig. Molecular sieves were used to obtain dry nitrogen. A sample solution was prepared by dissolving the polymer sample in ODCB-m at 160°C under vibration for 2 hours using an autosampler. 300 μL of the sample solution was injected into the column. The temperature profile of the CEF was as follows: crystallization from 110°C to 25°C at a rate of 3°C / min, thermal equilibrium at 30°C for 5 minutes (including a soluble fraction elution time set to 2 minutes), and elution from 25°C to 140°C at a rate of 3°C / min. The flow rate during crystallization was 0.052 mL / min. The flow rate during elution was 0.50 mL / min. IR-4 signal data were collected at one data point / second.

[0159] CEF columns were packed with glass beads (such as those commercially available from MO-SCI Specialty Products) at 125 pm ± 6% with 1 / 8 inch stainless steel tubing according to U.S. 2011 / 0015346 Al. The internal liquid volume of the CEF column was between 2.1 and 2.3 ml. Temperature calibration was performed by using a mixture of NIST Standard Reference Material Linear Polyethylene 1475a (1.0 mg / ml) and eicosane (2 mg / ml) in ODCB-m. The calibration consisted of the following four steps: (1) calculate the delay volume defined as the temperature offset between the measured eicosane peak elution temperature minus 30.00 °C; (2) subtract the temperature offset of the elution temperature from the CEF raw temperature data. It should be noted that the temperature offset is a function of experimental conditions such as elution temperature, elution flow rate, etc.; (3) generate a linear calibration line of the converted elution temperature over the range of 25.00 °C and 140.00 °C such that the peak temperature of the NIST Linear Polyethylene 1475a is 101.00 °C and the peak temperature of eicosane is 30.00 °C, (4) linearly extrapolate the elution temperature for the soluble fraction measured isothermally at 30 °C by using a 3 degrees Celsius / minute elution heating rate. The reported elution peak temperature was obtained such that the observed comonomer content calibration curve was consistent with those previously reported in U.S. 8,372,931.

[0160] The CEF fraction from 70 to 90 °C was defined as the integral of the elution temperature of the IR-4 chromatogram (baseline minus measured channel) over the range of 70.0 to 90.0 °C divided by the total integral from 25 to 140.0 °C according to the following equation:

[0161]

[0162] where T is the elution temperature (from the calibration discussed above).

[0163] The linear baseline was calculated by selecting two data points: one before polymer elution, typically at a temperature of 25.5 °C, and the other after polymer elution, typically at 118 °C. For each data point, the detector signal was subtracted from the baseline prior to integration.

[0164] Creep zero shear viscosity measurement method

[0165] Zero-shear viscosities were obtained via creep tests conducted on an AR-G2 stress controlled rheometer (TA Instruments; New Castle, Del.) using a 25 mm diameter parallel plate at 190 °C. The rheometer oven was set to the test temperature for at least 30 minutes before zeroing the fixtures. At the test temperature, a compression molded sample disk was inserted between the plates and allowed to come to equilibrium for 5 minutes. The upper plate was then lowered down onto the sample above the desired test gap (1.5 mm) by 50 μιη. Any excess material was trimmed off and the upper plate was lowered to the desired gap. Measurements were made under a nitrogen purge at a flow rate of 5 liters / minute. The default creep time was set to 2 hours.

[0166] A constant low shear stress of 20 Pa was applied to all samples to ensure that the steady shear rate was low enough to be in the Newtonian region. For the samples in this study, the resulting steady shear rate was in the range of 10 -3 to 10 -4 s -1 . Steady state was determined by linear regression on all data in the last 10% time window of the log(J(t)) versus log(t) curve, where J(t) is the creep compliance and t is the creep time. If the slope of the linear regression was greater than 0.97, then steady state was considered to have been reached and the creep test was stopped. In all cases in this study, the slope met the criteria within 2 hours. The steady shear rate was determined from the slope of the linear regression on all data points in the last 10% time window of the ε versus t curve, where ε is the strain. The zero-shear viscosity was determined from the ratio of the applied stress to the steady shear rate.

[0167] To determine if the sample had degraded during the creep test, a small amplitude oscillatory shear test was conducted on the same test specimen before and after the creep test from 0.1 to 100 rad / s. The complex viscosity values of the two tests were compared. If the viscosity value at 0.1 rad / s differed by more than 5%, then the sample was considered to have degraded during the creep test and the results were discarded.

[0168] The zero-shear viscosity ratio (ZSVR) is defined as the ratio of the zero-shear viscosity (ZSV) of the branched polyethylene material to the ZSV of a linear polyethylene material at the equivalent weight average molecular weight (Mw-gpc) according to the following equation:

[0169]

[0170] ZSV values were obtained from the creep test at 190°C via the method described above. Mw-gpc values were determined by the conventional GPC method. A correlation between ZSV and its Mw-gpc for linear polyethylenes was established based on a series of linear polyethylene reference materials. The description of the ZSV-Mw relationship can be found in the ANTEC proceedings: Kariala, Teresa P.; Sammler, Robert L.; Mangnus, Marc A.; Hazlitt, Lonnie G.; Johnson, Mark S.; Hagen, Charles M., Jr.; Huang, Joe W. L.; Reichek, Kenneth N. Detection of Low Level Long Chain Branching in Polyolefins. Annual Technical Conference - Society of Plastics Engineers (2008), 66th 887-891.

[0171] 1 H NMR method

[0172] In a 10 mm NMR tube, 3.26 g of stock solution was added to 0.133 g of polyolefin sample. The stock solution was a mixture of tetrachloroethane-d2(TCE) and perchloroethylene (50:50, w:w) with 0.001 M Cr 3+ The solution in the tube was purged with N2for 5 minutes to reduce the amount of oxygen. The capped sample tube was left at room temperature overnight to swell the polymer sample. The sample was dissolved by shaking at 110 °C. The sample was free of additives that can contribute to unsaturation, such as slip agents like erucamide.

[0173] 1 H NMR was run on a Bruker AVANCE 400 MHz spectrometer at 120 °C with a 10 mm cryoprobe.

[0174] Two experiments were run to obtain the unsaturation: control and double pre-saturation experiments.

[0175] For the control experiment, the data was processed with an exponential window function of LB = 1 Hz, baseline corrected from 7 to -2 ppm. The residual 1 H signal of TCE was set to 100, the integral I total was used as the signal of the whole polymer in the control experiment. The number of CH2groups in the polymer, NCH2, was calculated as follows:

[0176] NCH2= I total / 2

[0177] For the double pre-saturation experiments, data were processed with an exponential window function of LB = 1 Hz, baseline corrected from 6.6 to 4.5 ppm. The residual 1H signal of TCE was set to 100, and the corresponding integrals (I 次亚乙烯基 三取代 乙烯基 亚乙烯基 ) were integrated based on the regions shown in the figure below

[0178]

[0179] The number of unsaturation units of vinylidene, tri-substituted, vinyl, and vinylene were calculated as follows:

[0180] N 次亚乙烯基 = I 次亚乙烯基 / 2

[0181] N 三取代 = I 三取代

[0182] N 乙烯基 = I 乙烯基 / 2

[0183] N 亚乙烯基 = I 亚乙烯基 / 2

[0184] The number of unsaturation units per 1,000,000 carbons was calculated as follows:

[0185] N 次亚乙烯基 / 1,000,000 C = (N 次亚乙烯基 / NCH2) * 1,000,000

[0186] N 三取代 / 1,000,000 C = (N 三取代 / NCH2) * 1,000,000

[0187] N 乙烯基 / 1,000,000 C = (N 乙烯基 / NCH2) * 1,000,000

[0188] N 亚乙烯基 / 1,000,000 C = (N 亚乙烯基 / NCH2) * 1,000,000

[0189] ​​​The requirements for unsaturation NMR analysis include: quantitative level of Vd2 of 0.47 ± 0.02 / 1,000,000 carbons with 200 scans (data acquisition less than 1 hour, including time to run control experiment) with sample at 3.9 wt% (for Vd2 structure, see Macromolecules, 2005, vol. 38, 6988), 10 mm high temperature cryoprobe. Quantitative level defined as 10 signal to noise.

[0190] The residual proton of TCT-d2 was 1 The chemical shift reference for the H signal was set at 6.0 ppm. The control was run using ZG pulse, TD 32768, NS 4, DS 12, SWH 10,000 Hz, AQ 1.64 s, Dl 14 s. The double presaturation experiment was run using the modified pulse sequence, OlP 1.354 ppm, 02P 0.960 ppm, PL9 57 db, PL21 70 db, TD 32768, NS 200, DS 4, SWH 10,000 Hz, AQ 1.64 s, Dl 1 s, Dl 313 s. The modified pulse sequence for unsaturation using the Bruker AVANCE 400 MHz spectrometer is shown below:

[0191]

[0192] Film test conditions

[0193] The following physical properties were measured on the films prepared:

[0194] Tensile test: ISO 527-3

[0195] Shrinkage ASTM D2732

[0196] Puncture: ASTM D-5748

[0197] Hydrohead: ISO 1420

[0198] Water vapor transmission rate (WVTR): ASTM E398 (measured on Lissy)

[0199] The application can be implemented in other forms without departing from the spirit and essential attributes of the application and, accordingly, reference should be made to the appended claims, rather than to the foregoing specification, as indicating the scope of the application.

Claims

1. A breathable film comprising at least one film layer, the film layer comprising a polymer composition, the polymer composition comprising 30 to 60 weight percent of a linear low density polyethylene, the linear low density polyethylene exhibiting the following various properties: (1) a CEF fraction of 70 to 90°C equal to or greater than 80% of the total CEF fraction; (2) a melt index, I2, of 3.0 to 3.5 g / 10 min measured according to ASTM D 1238 at 190°C and a load of 2.16 kg; (3) melt flow ratio I 10 I2is equal to or less than 6.7, I2and I 10 are measured according to ASTM D 1238 at 190 °C and under a load of 2.16 kg and 10 kg, respectively; (4) a density of 0.915 to 0.940 g / cm3measured according to ASTM D792; and 3 a density of 0.915 to 0.940 g / cm3measured according to ASTM D792; and (5) a molecular weight distribution Mw / Mn in the range of 2.0 to 2.4 w / M n , wherein the linear low density polyethylene comprises units derived from ethylene and units derived from 1-hexene.

2. The breathable film according to claim 1, wherein the polymer composition further comprises 40 to 60 weight percent of CaCC.

3. The breathable film according to claim 1, wherein the linear low density polyethylene does not comprise units derived from 1-octene.

4. The breathable film according to claim 1, wherein the polymer composition further comprises greater than 0 to equal to or less than 5 weight percent of one or more compounds selected from the group consisting of pigments and antioxidants.

5. The breathable film according to claim 1, wherein the polymer composition further comprises greater than 0 to equal to or less than 10 weight percent of one or more compounds selected from the group consisting of polypropylene and low density polyethylene.

6. The breathable film according to claim 1, wherein the at least one film layer comprises 45 to 55 weight percent of the linear low density polyethylene and 55 to 45 weight percent of CaCC.

7. The breathable film according to claim 1, wherein the polymer composition further comprises a filler.

8. A method of making the breathable film according to claim 1, the method comprising cast extruding or blown extruding the polymer composition.

9. The method according to claim 8, wherein the machine direction is oriented at a stretch ratio equal to or greater than 1.

5.

10. A breathable film made according to the method of claim 8.

11. The breathable film according to claim 10, further comprising one or more additional film layers.

12. An article comprising the breathable film according to claim 1, wherein the article is selected from the group consisting of diapers, feminine hygiene products, adult incontinence products, bed liners, animal training products, and animal incontinence products.

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