WO2004060994A1

WO2004060994A1 - Elastic blends comprising elastic crystalline polymer and crystallizable polymers for ethylene

Info

Publication number: WO2004060994A1
Application number: PCT/US2003/039907
Authority: WO
Inventors: Andy H. Tsou; Srivatsan Srinivas; Andrew J. Peacock; Bryan R. Chapman; Sudhin Datta
Original assignee: Exxonmobil Chemical Patents Inc.
Priority date: 2002-12-17
Filing date: 2003-12-16
Publication date: 2004-07-22
Also published as: AU2003297134A1

Abstract

Hetero phase polymer blends are contemplated having a continuous phase of a propylene rich polymer and a dispersed phase of an ethylene polymer, or the dispersed phase can be another propylene rich polymer, or the dispersed phase may be a blend of an ethylene rich polymer and a propylene rich polymer. The crystallinity type of the continuous and dispersed phases are different. The blends exhibit ratio of the 500 % tensile modulus of the blend to the 500 % tensile modulus of the propylene rich polymer component (of the continuous phase), unblended, of ≤ 1.6 at a tension set of ≤ 98 %. The blends may exhibit low flexural modulus properties, generally ≤ 140,000 psi. The propylene rich polymer of the continuous phase also may exhibit a heptane insoluble level < 88 %. Films, fibers, fabrics, and molded articles are among the contemplated uses of the polymer blends.

Description

ELASTIC BLENDS COMPRISING ELASTIC CRYSTALLINE POLYMER

AND CRYSTALLIZABLE POLYMERS FOR ETHYLENE

[0001] This application claims the benefit of U.S. Provisional Application No.

60/434,097, filed December 17, 2002, the entire disclosure of which is hereby incorporated herein by reference.

FIELD OF INVENTION

[0002] Embodiments of our invention relate to a blend of at least two polymeric components differing in their crystallinity type. The blend may be a hetero phase morphology composition comprising at least one copolymer of propylene and one or more of ethylene, and/or C4-C20 α-olefins and at least one copolymer of ethylene and one or more of C3-C20 α-olefins, and/or at least one propylene polymer or combinations thereof.

BACKGROUND

[0003] U.S. Patent No. 6,231,936 suggests a blend of polypropylene with an ethylene α-olefm polymer for articles such as packaging materials and medical devices that require radiation and/or heat resistance for their applications. The propylene may be a homopolymer or copolymer, produced with a Ziegler-Natta or metallocene catalyst, and be relatively low in crystallinity. The propylene polymer is described as having a heptane insolubles content of from 88 to 99%. The propylene polymers may have a comonomer of a C2 to C20 α-olefin, and/or a diene. The propylene polymers may have a molecular weight distribution (M D) of from 1 to 9. The ethylene polymers are generally described as being produced with a metallocene catalyst and exhibit densities of from 0.85 to 0.965 g/cc, a MWD of from 1 to 4 and a CDBI greater than 45%. The ethylene polymer may generally be in the blend in the range of from 1 to 50 wt%.

[0004] WO Publication No 98/21275 suggests a metallocene catalyzed ethylene copolymer blended with an impact copolymer polypropylene (ICP) for impact modification of the polypropylene. The 1% secant modulus of the blend is generally above 140,000 psi (966 MPa). The rubber is present in the ICP in an amount of from 4-20 wt% and the rubber portion contains ethylene in an amount of from 30 to 65 wt%. The ethylene polymer is a copolymer of ethylene and an α-olefin having from 4-10 carbon atoms, with a density from 0.88-0.925 g/cc. The ethylene polymer is present in the blend in an amount of from 5 to 40 wt%.

[0005] The above documents describe polypropylene blend formulations in applications where relatively high stiffness (high modulus) is desirable. There is a need in the art for polymeric blends having good tensile strength while still providing good elasticity, i.e., mechanical recoverability (elastic recovery or lack of tension set) and flexibility (low flexural modulus).

[0006] Other background references include U.S. Patent No. 6,576,306, WO

Publication Nos. 00/70134 and 00/01766, U.S. Patent Application Publication No. 2001/053837, and EP Publication No. 0 550 214.

SUMMARY

[0007] We have discovered that compositions comprising at least one propylene polymer or polymers as at least one first component with other polymers as at least one second component, where the at least one first component or components and the at least one second component, have different crystallinity, such compositions may generally be heterophase compositions, and may have resistance to elastic deformation (permanent set) when articles made from such compositions are extended or elongated.

[0008] The term hetero phase compositions refers to the presence of at least two phases: a continuous or matrix phase and a discontinuous or disperse phase distributed within the matrix phase. Each phase can itself be a blend, as long as the crystallinity of the matrix phase and discontinuous phase or phases are different, as herein defined. In certain polymer compositions, a two or more phase system may be co-continuous, that is the two or more phases are still divided, but an observer cannot tell, based on the amounts of each phase, which is the continuous phase and which is the dispersed phase. Such systems, while still hetero phase, are said to be co- continuous, and are contemplated as embodiments of our invention. [0009] Contemplated are compositions, substantially devoid of compatibilizer, comprising at least one first component and at least one second component, wherein: a) the composition comprises a ratio of the at least one first component to the at least one second component, in the range of 1 :99 to 99:1, based on the total polymer content of the blend, and crystallinity of the at least one first component being propylene crystallinity;

(b) wherein the at least one second component contains crystallinity different from the crystallinity of the at least one first component;

(c) and wherein a ratio of 500% tensile modulus of the composition to the 500% tensile modulus of the at least one first component, unblended, is < 1.6, wherein the tension set of the composition is < 98%.

DESCRIPTION OF DRAWINGS

[0010] Figure 1 is a graphical representation of the ratio of 500% tensile modulus of a composition as herein described, to the 500% tensile modulus of the at least one first component (unblended), versus permanent set.

DETAILED DESCRIPTION

[0011] We contemplate embodiments of our invention where hetero phase compositions comprised of at least one first component of a propylene rich polymer, and at least one second component, this at least one second component may be one or more of i) generally an ethylene rich polymer or ii) generally a propylene rich polymer, where the crystallinity of the at least one first component and crystallinity of the at least one second component, differ in crystallinity type and may also differ in amount of crystallinity. By propylene or ethylene rich we intend that > 50 weight percent of the polymer be the rich monomer. These hetero phase compositions may include a homogeneous macromolecular copolymer structure as the at least one first component, and at least one homopolymer or copolymer of ethylene and at least one α-olefin as the at least one second component. Embodiments of our invention are directed to hetero phase morphology compositions where at least one first component may be a copolymer of propylene and at least one C2, C4-C20 α-olefins and at least one second component may be a copolymer of ethylene and at least one C3-C20 α- olefin. [0012] Following is a detailed description of certain blend combinations of ethylene rich and propylene rich polymers, their fabrication into useful articles such as films, sheets, fibers, fabrics, molded articles, adhesive components, and the use of these articles.

Blends

[0013] In embodiments of our invention we contemplate that at least one first component, selected from propylene rich polymers, may be present in the composition in a ratio of at least one first component to at least one second component of 1:99 to 99:1, or 95:5 to 5:95, or 10:90 to 90:10, or 15:85 to 85:15, or

20:80 to 80:20, or 25:75 to 75:25, or 30:70 to 70:30, or 35:65 to 65:35, or 40:60 to

60:40 or 45:55 to 55:45, or 50:50.

[0014] Embodiments of our invention include blend compositions where the two major components may have different crystallinity. Ethylene and propylene or isotactic and syndiotactic are examples of differing crystallinities of the two major composition components. By differing crystallinities we intend:

[0015] The presence of crystallinity and its amount may be determined by using either differential scanning calorimetry (DSC) or wide angle x-ray scattering (WAXS). Further, the crystallinity type may be determined by 13C NMR (Nuclear Magnetic Resonance) or Fourier Transform Infrared Spectroscopy (FTIR) as being ethylene crystallinity, propylene crystallinity, and if propylene crystallinity the type of crystallinity (syndiotactic, isotactic).

[0016] As a method of determining the relative flexibility/extensibility of compositions of embodiments of our invention, a ratio of the 500% tensile modulus of the composition, to the 500% tensile modulus of the at least one first component, unblended, may be used. In embodiments of our invention, this ratio may be < 1.6, or <1.5, or <1.45, or < 1.4, or < 1.35, or < 1.30. This ratio may be achieved generally at a tension set of the composition of < 98% or < 95% or <90% or ≤ 88%, or < 85%, or < 82%, or < 80%.

[0017] The compositions of embodiments of our invention may generally be devoid of compatibilizer. Compatibilizers are known by those of skill in the art to be those polymers that are compatible with both the continuous and disperse phases. By devoid, we intend that no polymer that acts in a compatibilizing way or other compatibilizing agent is added. And this may generally mean < 1.0 wt.%, or < 0.5 wt.%, or < 0.1 wt.%, of any such material or materials may be present, or none detectable by current analytical techniques. Further, no compatibilizing agent or polymer may be intentionally added.

[0018] In other embodiments of our invention, the 1% secant (flexural) modulus of the composition, as determined by according to ASTM D 790A, with a crosshead speed of 1.27 mm/min (0.05 in/min), and a support span of 50.8 mm, using an Instron machine, may be < 140,000 psi, or < 130,000 psi, or < 125,000 psi, or < 120,000 psi, or < 115,000 psi, or < 105,000 psi, or < 100,000 psi, or < 90,000 psi, or < 80,000 psi.

[0019] Other additives, provided that they do not act as compatibilizers, may be part of the compositions of embodiments of our invention. Additives which may be incorporated comprise, for example, fire retardants, antioxidants, plasticizers, pigments, vulcanizing or curative agents, vulcanizing or curative accelerators, retarders, processing aids, flame retardants, tackifying resins, dyes, waxes, heat stabilizers, light stabilizers, anti-block agents, processing aids, or combinations thereof. These compounds may include fillers, reinforcing materials (including granular, fibrous, or powder-like) or combinations thereof. These fillers comprise carbon black, clay, talc, calcium carbonate, mica, silica, silicate, and combinations thereof. Lubricants, mold release agents, nucleating agents, or combinations may also be employed. First Component

[0020] A general description of the at least one first component is contained in

U.S. Patent Application Publication 2002/0004575, published January 10, 2002, incorporated herein by reference for purposes of U.S. patent practice. [0021] In one embodiment, the at least one first component comprises from a lower limit of > 5% or > 6% or > 8% or > 10% by weight to an upper limit of < 20% or < 25% by weight ethylene and/or at least one α-olefin-derived unit, and from a lower limit of > 75% or > 80% by weight to an upper limit of <95% or < 94% or <92% or < 90% by weight propylene-derived units, the percentages by weight are based on the total weight of propylene and ethylene and/or at least one α-olefin- derived unit comprising the at least one first component. Optionally, ethylene can be replaced or added to in such polymers with one or more C4 - C20 or C4-C12 α- olefins, such as, for example, one or more of 1-butene, 1-hexene or 1-octene or 1- decene. Other olefinic monomers may comprise the at least one first component, these include linear, branched, or ring-containing C3 to C30 olefms or combinations thereof, capable of insertion polymerization. Branched α-olefins include 4-methyl-l-pentene, 3 -methyl- 1-pentene, and 3,5,5-trimethyl-l-hexene. Ring-containing olefinic monomers contain up to 30 carbon atoms and comprise for example, cyclopentene, vinylcyclohexane, vinylcyclohexene, norbornene, methyl norbornene, and combinations thereof.

[0022] Aromatic-group-containing monomers may contain up to 30 carbon atoms. Suitable aromatic-group-containing monomers comprise at least one aromatic structure, or from one to three, or may be a phenyl, indenyl, fluorenyl, or naphthyl moiety. The aromatic-group-containing monomer further comprises at least one polymerizable double bond such that after polymerization, the aromatic structure may be pendant from the polymer backbone.

[0023] Aromatic-group-containing monomers may contain at least one aromatic structure appended to a polymerizable olefinic moiety. The polymerizable olefinic moiety may be linear, branched, cyclic-containing, or a mixture of these structures. When the polymerizable olefinic moiety contains a cyclic structure, the cyclic structure and the aromatic structure may share 0, 1, or 2 carbons. The polymerizable olefinic moiety and/or the aromatic group may also have from one to all of the hydrogen atoms substituted with linear or branched alkyl groups containing from 1 to 4 carbon atoms. Aromatic monomers contemplated include styrene, alpha-methylstyrene, vinyltoluenes, vinylnaphthalene, allyl benzene, indene or combinations thereof.

[0024] In various embodiments, features of the at least one first component comprise one or more of the following characteristics, where ranges from any recited upper limit to any recited lower limit are contemplated.

(i) The at least one first component, according to an embodiment of our invention, may have a single, dual or multiple melting points. The at least one first component may be a random copolymer of ethylene and/or one or more α-olefins and propylene, having at least one melting point (Tm) by Differential Scanning Calorimetry (DSC) ranging from an upper limit of less than 110 °C, or less than 90 °C, or less than 80 °C, or less than 70 °C; to a lower limit of greater than 25 °C, or greater than 35 °C, or greater than 40°C or greater than 45°C. (ii) A heat of fusion, as determined by DSC, ranging from a lower limit of greater than 1.0 joule per gram (J/g), or greater than 1.5 J/g, or greater than 4.0 J/g, or greater than 6.0 J/g, or greater than 7.0 J/g, to an upper limit of less than 125 J/g, or less than 100 J/g, or less than 75 J/g, or less than 60 J/g, or less than 50 J/g, or less than 40 J/g, or less than 30 J/g. The crystallinity of the first component arises from stereo regular propylene sequences and such first components may be said to be crystalline if they show a Tm. By crystalline we intend that under certain conditions (i.e. temperature and/or stress) that crystallinity may be determined by DSC and/or WAXS. If a polymer meets such a test, that is having crystallinity under any conditions of temperature and/ or stress, it is said to be crystalline. The amount of crystallinity is not addressed by such a statement, (iii) A triad tacticity, as determined by carbon- 13 nuclear magnetic resonance (^I3C NMR), of greater than 75 %, or greater than 80 %, or greater than 85 %, or greater than 90 %. (iv) In embodiments of our invention, at least 75% by weight, or at least 80% by weight, or at least 85% by weight, or at least 90% by weight, or at least 95% by weight, or at least 97% by weight, or at least 99% by weight of the at least one first component may be soluble in a single temperature fraction, or in two adjacent temperature fractions, with the balance of the at least one first component in immediately preceding or succeeding temperature fractions. These percentages are fractions, for instance in hexane, beginning at 23 °C, and the subsequent fractions are in approximately 8°C increments above 23°C. Meeting such a fractionation requirement means that polymers have statistically insignificant intermolecular differences in tacticity or composition distribution.

(v) As a measure of the statistically insignificant intermolecular differences of composition, each of these fractions may have a composition (wt% ethylene and /or α-olefin content) with a difference of less than 1.5 wt. % (absolute) or less than 1.0 wt. % (absolute), or less than 0.8 wt. % (absolute) of the average wt. % ethylene content of the whole at least one first component. Meeting such a fractionation requirement means that a polymer has statistically insignificant intermolecular differences of composition, which is the ratio of propylene to ethylene and/or α-olefin.

(vi) In embodiments of our invention, the at least one first component may have a weight average molecular weight (Mw) of from 15,000 to 5,000,000, or from 20,000 to 1,000,000 and a molecular weight distribution (MWD) Mw/Mn ranging from a lower limit of 1.5 or 1.8 to an upper limit of 40, or 20, or 10, or 5, or 4.5.

(vii) The at least one first component may have predominantly (> 50 %, or > 60%, or > 70%) isotactic or syndiotactic sequences, but not both. For the at least one first component, the presence of isotactic or syndiotactic sequences can be determined by NMR measurements showing two or more propylene derived units arranged isotactically (or syndiotactically). In the at least one first component the isotactic (or syndiotactic) sequences may be interrupted by units which are not isotactically (or syndiotactically) arranged or by units that otherwise disturb the crystallinity derived from the isotactic (or syndiotactic) sequences.

(viii) According to another embodiment of the present invention, the at least one first component may contain small quantities of a non-conjugated diene. The amount of diene may be < 10 wt. % or < 5 wt. %. The diene may be selected from one or more of those which are used for the vulcanization of ethylene propylene rubbers such as ethylidene norbornene, vinyl norbornene or dicyclopentadiene.

[0025] The at least one first component may comprise a heptane insoluble fraction of < 88 %, or < 86%, or < 84%, or < 82%, or < 80%, or < 75%, or < 70%, or

< 65%, or < 60%, or < 50%. Heptane insolubility is a measure of the portion of a finely divided polypropylene sample which is insoluble in boiling heptane (1.5 hour boiling time). As the insolubility approaches 100%, the crystallinity of the resin approaches a maximum level in commercially available polypropylenes.

[0026] Additional polymer or polymers may be included in the at least one first component, each of which would qualify as at least one first component, as long as the crystallinity type of the at least one first component blend remains the same and comprises propylene crystallinity, that is, if the primary first component contains for instance, isotactic sequences, the other member or members of the at least one first component may also have isotactic sequences, or in the alternative, all would comprise syndiotactic sequences. There may be one, two, three, four or more other components of this first component, all having the same type of crystallinity, but having the same or different amount of crystallinity, and the same or different.

Second Component

[0027] In one embodiment, the major olefinic monomer in the at least one second component may be ethylene. In this embodiment the at least one second component may be polyethylene homopolymers, polyethylene copolymers or combinations thereof. If a copolymer, other olefinic monomers may be included, these include linear, branched, or ring-containing C3 to C30 olefms or combinations thereof, capable of insertion polymerization or these olefinic monomers may be C3 to C20 linear or branched α-olefins, or C3 to C8 α-olefms, or propylene, 1-butene, 1-hexene, and 1-octene. Branched α-olefins include 4-methyl-l-pentene, 3 -methyl- 1-pentene, and 3,5,5-trimethyl-l-hexene and combinations thereof. Ring-containing olefinic monomers may contain up to 30 carbon atoms and comprise cyclopentene, vinylcyclohexane, vinylcyclohexene, norbornene, methyl norbornene and combinations thereof.

[0028] Aromatic-group-containing monomers may contain up to 30 carbon atoms. Suitable aromatic-group-containing monomers comprise at least one aromatic structure, or from one to three, or may comprise a phenyl, indenyl, fluorenyl, naphthyl moieties or combinations thereof. The aromatic-group-containing monomer may further comprise at least one polymerizable double bond, such that after polymerization, the aromatic structure may be pendant from the polymer backbone. [0029] Aromatic-group-containing monomers may contain at least one aromatic structure appended to a polymerizable olefinic moiety. The polymerizable olefinic moiety may be linear, branched, cyclic-containing, or a mixture of these structures. When the polymerizable olefinic moiety contains a cyclic structure, the cyclic structure and the aromatic structure may share 0, 1, or 2 carbons. The polymerizable olefinic moiety and/or the aromatic group may also comprise from one to all of the hydrogen atoms substituted with linear _. or branched alkyl groups containing from 1 to 4 carbon atoms. Styrene, alpha-methylstyrene, vinyltoluenes, vinylnaphthalene, allyl benzene, indene or combinations thereof are examples of suitable aromatic monomers.

[0030] In one embodiment, the at least one polyethylene copolymer or at least one polyethylene homopolymer, or combinations thereof may be a polymer having a melting point, as determined by DSC, of 20°C or more, 40°C or more, 50°C or more, or 60°C or more, or 65°C or more, or 70°C or more. The polyethylene copolymer may have melting points of 125°C or less, or 120°C or less, or 130°C or less, or 140°C or less. Such melting points are determinative of crystallinity.

[0031] If the at least one second component comprises copolymers, typically, the average ethylene content may be > 40 mole %, or ≥ 50 mole %, or > 60 mole %, or > 70 mole %, or > 80 mole %, or >84 mole %, or > 87 mole %, or > 89 mole %. Or the average ethylene content may be < 100 mole %, or < 98 mole %. The balance of the copolymer may be one or more of the olefinic monomers discussed above, and optionally minor amounts of one or more diene monomers.

[0032] The density of the polyethylene copolymers or homopolymers, in g/cc, may be >0.860, or >0.865, or >0.870, or >0.880, or > 0.890, or > 0.900, or < 0.970, or < 0.960, or < 0.950 or < 0.940, or < 0.930, or have a range of >0.865- < 0.900 or > 0.900- < 0.930, or > 0.930- < 0.950, or > 0.950- <0.970.

[0033] The weight average molecular weight (Mw) of the polyethylene copolymer or homopolymer may typically be 30,000 or more, or 50,000 or more, or 80,000 or more. The Mw of the polyethylene copolymer or homopolymer may typically be 500,000 or less, or 300,000 or less, or 200,000 or less. [0034] Polyethylene homopolymers and copolymers suitable for use in embodiments of our invention may be produced using Ziegler-Natta or metallocene catalyst systems or may be combinations of polyethylenes produced by each. Polyethylene copolymers or homopolymers produced with metallocene catalysts may display narrow molecular weight distribution, meaning that the ratio of the weight average molecular weight to the number average molecular weight may be equal to or below 4, or in the range of from 1.7 - 4.0, or from 1.8 - 2.8.

[0035] These polyethylene homopolymers or copolymers may be made in a variety of processes (including slurry, solution, high pressure or gas phase) employing metallocene catalysts. Processes for making a variety of polyethylene materials with metallocene catalyst systems are well known. See, for example, U.S. Patent Nos. 5,017,714, 5,026,798, 5,055,438, 5,057,475, 5,096,867, 5,153,157, 5,198,401, 5,240,894, 5,264,405, 5,278,119, 5,281,679, 5,324,800, 5,391,629, 5,420,217, 5,504,169, 5,547,675, 5,621,126, 5,643,847, and 5,801,113, U.S. patent application serial nos. 08/769,191, 08/877,390, 08/473,693, 08/798,412, and 60/048,965, and international patent application nos. EPA 277,004, WO 92/00333, and WO 94/03506, each fully incorporated herein by reference for purposes of U.S. patent practice. Production of copolymers of ethylene and cyclic olefms are described in U.S. Patent Nos. 5,635,573 and 5,837,787, and copolymers of ethylene and geminally di- substituted monomers, such as isobutylene, are described in U.S. Patent No. 5,763,556, all of which are fully incorporated herein for purposes of U.S. patent practice.

[0036] Polyethylene copolymers produced with metallocene catalysts may also display narrow composition distribution, meaning that the fractional comonomer content from molecule to molecule will be similar. This can be measured by FTIR analysis of discrete ranges of number or weight average molecular weights (Mn or Mw) as identified with Gel Permeation Chromatography (GPC-FTIR), and in limited cases, composition distribution breadth index or solubility distribution breadth index may also be used to measure comonomer distribution. One contemplated polyethylene copolymer has a comonomer distribution when measured by GPC-FTIR, such that the comonomer content of any discrete molecular weight range comprising 10 weight % or more of the total eluted copolymer may be within ±30% of the weight average comonomer content of the polyethylene copolymer, where the average equates to 100%), or within ±20%), or within ±10%. Where measurement by SDBI is applicable, the SDBI of the polyethylene copolymer may be less than 35°C, generally in the range of 10° to 25°C, or in the range of 15° to 20°C, or in the range of 15° to 18° C. Where CDBI is applicable, the CDBI of the polyethylene copolymer may be greater than 40%), or greater than 50%, or greater than 60%. The polyethylene copolymer may have a narrow composition distribution if it meets the GPC-FTIR, CDBI, or SDBI criteria as outlined above.

[0037] The at least one second component can itself be a combination of two or more ethylene polymers, as long as each of the polymers in the at least one second component individually qualify as at least one second component, that is, that the crystallinity of the at least one second component be different from the crystallinity of the first component. If two or more polymers are a part of the at least one second component, they may be the same or different in other micro and/or macro properties, but in combinations they comprise different crystallinity than the at least one first component.

[0038] In another embodiment, the at least one second component can be at least a propylene rich polymer, and if so, its crystallinity as determined by WAXS/NMR may be different propylene crystallinity than that of the at least one first component. [0039] Three or more part blends are also contemplated, as long as the physical parameters discussed herein apply and as long as the crystallinity of the at least one second component is different from the at least one first component or components. With the at least one first component of isotactic crystallinity, the at least one second component may be an ethylene crystallinity and/or syndiotactic crystallinity. With the at least one first component of syndiotactic crystallinity, the at least one second component may be an ethylene crystallinity and/or isotactic crystallinity. Process oil

[0040] Process oil may be optionally added to the compositions of embodiments of the present invention. The addition of process oil in moderate amounts may lower the viscosity and flexibility of the composition while improving the properties of the composition at temperatures near and below 0°C. [0041] The process oils may comprise hydrocarbons comprising of carbon and hydrogen with traces of hetero atoms such as oxygen or comprising carbon, hydrogen and at least one hetero atom such as dioctyl phthalate, ethers and polyethers. The process oils may have a boiling point to be substantially involatile at 200°C. These process oils are commonly available either as neat solids or liquids or as physically absorbed mixtures of these materials on an inert support (e.g. clays, silica) to form a free flowing powder. We believe that all forms of these process oils are equally applicable to the description and the practice of embodiments of our invention. [0042] The process oils may comprise mixtures of a large number of chemical compounds which may consist of linear, acyclic but branched, cyclic and aromatic carbonaceous structures. Another family of process oils are certain low to medium molecular weight (Molecular weight (Mn) <10,000) organic esters and alkyl ether esters. Examples of process oils are Sunpar® 150 and 220 from The Sun Manufacturing Company of Marcus Hook, PA, USA and Hyprene® N750 and Hyprene N1200 from Ergon, Post Office Box 1639, Jackson, MS 39215-1639, USA. and IRM 903 from Calumet Lubricants Co., 10234 Highway 157, Princeton, LA 71067-9172, USA. It is also anticipated that combinations of process oils each of which is described above may be used in the practice of embodiments of the invention. [0043] The addition of the process oils to the composition comprising the at least one first component and the at least one second component may be made by any of the conventional means known to the art. These include the addition of all or part of the process oil prior to recovery of the polymer as well as addition of the process oil, in whole or in part, to the polymer as part of compounding for the interblending of the at least one first component and the at least one second component. The compounding step may be carried out in a batch mixer such as a mill or an internal mixer such as Banbury mixer. The compounding operation may also be conducted in a continuous process such as a twin screw extruder.

[0044] The addition of certain process oils to lower the glass transition temperature of blends of isotactic polypropylene and ethylene propylene diene rubber has been described in the art by Ellul in US Patents 5,290,886 and 5,397,832. We expect these procedures may be applicable to the at least one first component and the at least one second component composition discussed herein.

[0045] The at least one first component and the at least one second component composition may include process oil in the range of from 1 to 200, or in the range of from 2 to 50 parts by weight of process oil per hundred parts of total polymer (at least one first component plus at least one second component). Test Methods

[0046] Tensile modulus was measured by ASTM method D-1708, if small amounts of sample were available (if sample amounts were below 70 grams), and/or by ASTM method D-412 if larger amounts of sample were available (if sample amount was larger than 70 gm).

[0047] Heptane Insolubles - Insolubles may be measured on bulk polymer samples dried at 100° C in a vacuum oven prior to boiling in n-heptane for 1.5 hours. Thereafter, samples are vacuum dried, rinsed with acetone, dried further in a vacuum oven at 100° C and thereafter heated in a muffle furnace for 8 hours at 1100° F (593° C). Heptane insolubles = 100 x weight of sample after heating in muffle furnace divided by weight of the sample prior to combining with n-heptane. [0048] Mooney viscosity was measured by ASTM method D- 1646.

[0049] Melt Index (MI) was measured by ASTM method D-1238(E).

[0050] Melt Flow Rate (MFR) was measured by ASTM method D-1238(L). [0051] Density in g/cc is determined in accordance with ASTM 1505, based on ASTM D-1928, procedure C, plaque preparation.

[0052] The composition of ethylene propylene copolymers was measured as ethylene wt% according to ASTM D 3900.

[0053] The composition of the first component was measured as ethylene wt% according to the following technique. A thin homogeneous film of the at least one first polymer component, pressed at a temperature of or greater than 150°C was mounted on a Perkin Elmer PE 1760 infra red spectrophotometer. A spectrum of the sample from 2600 cm-1 to 20400 cm-1 was recorded and the ethylene wt% of the first polymer component was calculated according to Equation 1 as follows: ethylene wt.% = 82.585 -111.987 X +30.045X² (1) wherein X is the ratio of the peak height at 1155 cm^" and peak height at either 722

-1 -1 cm or 732 cm , which ever is higher.

[0054] Techniques for determining the molecular weight (Mn and Mw) and molecular weight distribution (MWD) are found in U.S. Patent 4,540,753 (Cozewith, Ju and Nerstrate) (which is incorporated by reference herein for purposes of U.S. practices) and references cited therein and in Macromolecules, 1988, volume 21, p 3360 (Nerstrate et al) (which is herein incorporated by reference for purposes of U.S. practice) and references cited therein.

[0055] Comonomer content of discrete molecular weight ranges can be measured by Fourier Transform Infrared Spectroscopy (FTIR) in conjunction with samples collected by GPC. One such method is described in Wheeler and Willis (Applied Spectroscopy, 1993, vol. 47, pp. 1128-1130). Different but similar methods are equally functional for this purpose and well known to those skilled in the art. [0056] Comonomer content and sequence distribution of the polymers may be measured by carbon 13 nuclear magnetic resonance (C-13 ΝMR), and such method is well known to those skilled in the art.

[0057] The procedure for Differential Scanning Calorimetry, for determining, for instance, crystallinity, is described as follows. 6 to 10 mg of a sheet of the polymer pressed at between 200°C to 230°C is removed with a punch die. This is annealed at room temperature for 240 hours. At the end of this period, the sample is placed in a Differential Scanning Calorimeter (Perkin Elmer 7 Series Thermal Analysis System) and cooled to between -50°C to -70°C. The sample is heated at 20°C/min to attain a final temperature of between 200°C to 220°C. The thermal output is recorded as the area under the melting peak of the sample which is typically peaked at between 30°C to 175°C and occurs between the temperatures of 0°C and 200°C, and is measured in Joules/gm as a measure of the heat of fusion. The melting point is recorded as the temperature of the greatest heat absorption within the range of melting of the sample. [0058] Composition Distribution Breadth Index (CDBI), is defined as the weight percent of the copolymer molecules having a comonomer content within 50% (that is 50% on each side) of the median total molar comonomer content. CDBI measurements can be made utilizing Temperature Rising Elution Fraction (TREF), as is now well known in the art. The technique is described by Wild et al. in the Journal of Polymer Science, Polymer Physics Edition, vol. 20, pg. 441 (1982), and in WO 93/03093, published 18 February 1993.

[0059] Solubility Distribution Breadth Index (SDBI) is a means to measure the distribution of comonomer within a copolymer having components of varying molecular weights and MWD's as described in U.S. Patent No. 5,008,204 and WO 93/03093.

[0060] All disclosures and specifications referred to in the above descriptions of testing procedures are fully incorporated herein by reference for purposes of U.S. patent practice.

Sample Preparation and Testing

[0061] Experiments were performed with the following blend components.

[0062] The at least one first component propylene copolymers containing ethylene as a comonomer are shown below (Table 1). These copolymers were produced using a chiral metallocene catalyst known to favor statistically random incorporation of the ethylene comonomer and propylene addition to produce isotactic runs. The copolymer is a thermoplastic elastomer with derived crystallinity resulting from isotactic polypropylene pentads. This copolymer was produced in accordance with the description in U.S. Patent Application Publication 2002/0004575, published January 10, 2002. [0063] The at least one second component polymers were ethylene copolymers containing butene, hexene or octene as the comonomer, with the balance being ethylene. Any crystallinity in these copolymers results from crystalline sequences of ethylene as determined by WAXS. The at least one second component ethylene copolymers are shown below (Table 2). Exceed and Exact are registered trademarks of, and are commercially available from, ExxonMobil Chemical Company, Houston, TX. Ethylene polymers called EO1, EO2 and EO3 in the table have been made according to the procedure described below: General Polymerization procedure

[0064] Polymerizations were carried out in a stirred tank reactor with continuous flow of feeds to the system and continuous withdrawal of products. Solvent (hexanes) and monomers (ethylene, and alpha-olefins) were purified over beds of alumna and/or mole sieves. Toluene for preparing catalyst solutions was also purified by the same technique. All feeds were pumped into the reactors by metering pumps, except for the ethylene and hydrogen that flowed as a gas through a mass flow meter/controller. Reactor temperature was controlled either by circulating water through a reactor cooling jacket, or by controlled chilling of the feeds and using the heat of polymerization to heat the reactor. The reactors were maintained at a pressure in excess of the vapor pressure of the reactant mixture to keep the reactants in the liquid phase. The reactors were operated liquid full.

[0065] Ethylene and alpha-olefin feeds were combined into one stream and then mixed with a pre-chilled hexane stream. A hexane solution of an alkyl aluminum scavenger was added to the combined solvent and monomer stream just before it entered the reactor to further reduce the concentration of any catalyst poisons. A mixture of the catalyst components in toluene or toluene/solvent mixture was pumped separately to the reactor and entered through a separate port. The product of the reactor exited through a pressure control valve. Polymer finishing included a concentration step, heat and vacuum stripping and pelletization.

Catalyst Activation [0066] μ-(p-Et3SiPh)2C(Cp)(2,7di-t-BuFlu)HfMe2 was pre-activated with

N.N'-dimemylanilmium tetrakis (perfluoronaphthyl) borate [DMAH+ B(pfn)4-] in toluene under an inert atmosphere. This mixture was allowed to activate until the evolution of methane stopped (~5 min.), and then sealed for nitrogen pressure transfer to a delivery vessel. The catalyst solution was pumped to the reactor from the delivery vessel at a controlled rate using a calibrated HPLC pump.

Copolymer Synthesis

[0067] A mixture of hexanes (64 Kg/h) and a scavenger solution of tri-n- octylaluminum in hexane were pumped into a 25 liter, liquid filled, stirred tank reactor for at least 20 min before monomers were introduced. Toluene solutions of catalyst and activator were pumped separately to the reactors as described above. Octene was pumped to the solvent line as a liquid. Ethylene was delivered as a gas in a controlled fashion through a mass flow meter/controller and dissolved in the solvent feed line before entering the reactor. After polymerization was established, reactor samples were collected every 2 to 4 hours for analysis and adjustments made to the process to achieve the desired product properties. Reactor effluent was quenched, concentrated, stabilized, heated, and dried under vacuum in various finishing units. Finally, the product was pelletized and collected.

Table 1 First Component (FBC) polymers used in blends

Table 2 Second Component (labeled SBC) polymers used in blends

[0068] The compositions of the at least one first component and the at least one second component and other components may be prepared by any procedure that provides an intimate mixture of the components. For example, the components can be combined by melt pressing the components together on a Carver press to a thickness of 0.5 millimeter (20 mils) and a temperature of 180°C, rolling up the resulting slab, folding the ends together, and repeating the pressing, rolling, and folding operation 10 times. Internal mixers are particularly useful for melt blending. Blending at a temperature of between 180°C to 240°C in a Brabender Plastograph for between 1 to , 20 minutes has been found satisfactory. Still another method that may be used for mixing the components involves blending the polymers in a Banbury internal mixer above the flux temperature of all of the components, e.g., 180°C, for 5 minutes. A complete mixture of the polymeric components is indicated by the uniformity of the morphology of the dispersion of the at least one first component and the at least one second component. Continuous mixing may also be used. These processes are well known in the art and include single and twin screw mixing extruders, static mixers for mixing molten polymer streams of low viscosity, impingement mixers, as well as other machines and processes, designed to disperse the first polymer component and the second polymer component in intimate contact.

[0069] The components may be selected based on the morphology desired for a given application. Those skilled in the art can select the volume fractions of the two components to produce a dispersed at least one second component morphology in a continuous at least one first component matrix, based on the viscosity ratio of the components (see S. Wu, Polymer Engineering and Science, Nol. 27, Page 335, 1987). [0070] Compositions were made by mixing all components, including the at least one first component, the at least one second component, the optional amounts of process oil and other ingredients in a Brabender intensive mixture for 3 minutes at a temperature controlled to be within 185°C and 220°C. High shear roller blades were used for the mixing and approximately 0.4g of Irganox® -1076, an antioxidant available from the Νovartis Corporation, was added to the blend. At the end of the mixing, the mixture was removed and pressed out into a 6" x 6" mold into a pad 0.025" thick at 215°C for 3 to 5 minutes. Films of 0.004" thickness were pressed out in a 4" x 4" mold at 200 °C for 3 to 5 minutes. At the end of this period, the pad was cooled and removed and allowed to anneal for 14 days, at room temperature. Test specimens of the required dumbbell geometry were removed from this pad and evaluated on Instron 4465 or Instron 4505 testers to produce the mechanical deformation data. The Instron Tester and associated equipment is available from The Instron Corporation in Canton, MA. All data is reported in engineering stress and strain terms with values of the stress uncorrected for the contraction in the cross- section of the sample being tested.

[0071] Tension set was determined on the samples of the composition which had been extended on the Instron to 200% extension and then allowed to relax. The samples were removed and the length (L2) of the deformation zone, between the grips on the Instron, was measured after 10 minutes. The original distance between the grips was the original length (LI) of the deformation zone. The tension set (TSet) is given by the formula Tset = 100*(L2-Ll)/Ll

EXAMPLES [0072] Compositions of the at least one first component and the at least one second component were made in proportions shown below in the Tables, according to the procedure described above. Properties of the blends were measured as molded. [0073] In each of Tables 3-12 that follow, the 500% tensile modulus and tension set for compositions of the at least one first component and the at least one second component are shown in the respective Table. Examples 1-9: Table 3

Comparative Examples 10-18:

[0074] In these examples, compositions of first components, with three different homopolypropylene samples PP 4292, PD 4443 and ACHIEVE® 3854, available from ExxonMobil Chemical Co., Houston TX, were made in compositions of Table 4, using the procedure described above. Table 4

Examples 19-26: Table 5

Comparative Examples 27-29:

[0075] In these examples, compositions of at least one first component with homopolypropylene PP 4292, available from ExxonMobil Chemical Co., Houston

TX, were made as seen in Table 6, using the procedure as described above.

Table 6

Examples 30-37: Table 7

Examples 38-45: Table 8

Examples 46-53: Table 9

Examples 54-57: Table 10

Examples 58-61: Table 11

Examples 62-65: Table 12

[0076] Certain features of the present invention are described in terms of a set of numerical upper limits and a set of numerical lower limits. It should be appreciated that ranges from any lower limit to any upper limit are within the scope of the embodiments of the invention unless otherwise indicated.

Claims

CLAIMSWe Claim:

1. A composition, substantially devoid of compatibilizer, comprising at least one first component and at least one second component, wherein:

(a) said composition comprises a ratio of said at least one first component to said at least one second component, in the range of 1:99 to 99:1, based on the total polymer content of said composition, said at least one first component comprising propylene crystallinity;

(b) said at least one second component contains crystallinity different from said crystallinity of the at least one first component; and

(c) a ratio of 500% tensile modulus of the composition to the 500% tensile modulus of said at least one first component, unblended, is < 1.6, wherein the tension set of said composition is ≤ 98%).

2. The composition of claim 1, wherein said at least one first component crystallinity is one of isotactic or syndiotactic, wherein said crystallinity of said at least one second component is one of isotactic, syndiotactic, or ethylene crystallinity, and wherein said crystallinity of said at least one first and said at least one second components are different.

3. The composition of claim 2, wherein said at least one first component comprises at least one propylene copolymer of one of ethylene, at least one C4-C20 ot-olefin, or combinations thereof, wherein said ethylene and/or said at least one C4-C20 α-olefin comprises a total of > 2 wt. % or < 25 wt. % of said at least one first component; wherein said at least one first component comprises a heptane insolubles level of < 88%, and wherein said composition comprises a flexural modulus of < 140,000 psi.

4. The composition of claim 3, wherein the at least one second component comprises a polyethylene comprising a density, in g/cc, selected from one of >

0.860 - <0.900, > 0.900 - <0.930, > 0.930 - <0.950, or > 0.950 - < 0.970, and wherein said tension set of said composition is < 90 %.

5. The composition of claim 4, wherein said at least one second component has a melting point < 140° C, and at least one first component comprises one or more of: i) a triad tacticity > 75% ii) a narrow composition distribution, such that > 75 wt. % of the at least one first component may be isolated in thermal fractionation, in 2 adjacent soluble fractions, where each fraction differs < 20% from the average weight percent ethylene, at least one C4-C20 α-olefin, or combinations thereof of the total at least one first component; or iii) a melting point between > 25°C and < 110°C.

6. The composition of claim 5, wherein said at least one first component comprises a heat of fusion < 75 J/g or > 3 J/g, wherein said second component comprises melting point > 20°C or < 130° C and wherein said tension set of said composition is < 80%>.

7 The composition of claim 6, wherein said at least one first component has a melting point between > 35° C and < 70° C.

8. The composition of claim 7, wherein said at least one first component comprises a molecular weight distribution in the range of from 2.0 to 4.5, and wherein said composition comprises a hetero phase blend.

9. The composition of claim 8, further comprising a process oil.

10. An article made from the composition of claim 8, wherein said article is one of a film, a sheet, a fiber, a fabric, an adhesive component or a molded article.

11. The composition of any one of claims 1, 9, or 10, wherein said composition further comprises an additional at least one first component containing crystallinity of the same type as said at least one first component, and/or wherein said composition further also comprises an additional at least one second component, wherein said crystallinity of said at least one first component and said additional at least one first component comprise propylene crystallinity selected from one or more of isotactic and syndiotactic.

12. A blend comprising : a) at least one propylene polymer, said at least one propylene polymer comprising 5 to 25 % by weight of ethylene-derived units and 95 to 15% by weight of propylene-derived units, the at least one propylene polymer comprising: a melting point of from > 25 °C to < 90 °C, said at least one propylene polymer comprising propylene crystallinity, said at least one propylene polymer comprising a heptane insolubles level of≤ 86%; and b) at least one ethylene polymer, said at least one ethylene polymer comprising a polymer of ethylene derived units and at least one α-olefin derived unit, said at least one ethylene polymer comprising ethylene crystallinity, and comprising a melting point of from > 20°C to <140°C, wherein a ratio of 500% tensile modulus of the blend, to the 500% tensile modulus of said at least one propylene polymer, unblended, is <1.6, wherein said blend has a permanent set of < 99 %; and wherein said blend comprises a flexural modulus, of ≤ 125,000 psi.

13. The blend of claim 12, wherein said at least one propylene polymer comprises: i. a triad tacticity > 80%; ii. a narrow composition distribution, such that > 80 wt. % of the propylene polymer may be isolated in thermal fractionation, in 2 adjacent soluble fractions, where each fraction differs < 20% from the average weight percent ethylene of the total at least one propylene polymer; and iii. a melting point of from > 35°C to < 90°C.

14. The blend of claim 13, wherein said at least one propylene polymer comprises 8 to 20 % by weight of ethylene-derived units and 92 to 80% by weight of propylene-derived units, the at least one propylene polymer comprising: a melting point of from > 40 °C to < 80 °C and a composition distribution such that > 85 wt. % of the at least one propylene polymer may be isolated in thermal fractionation, in 2 adjacent soluble fractions.

15. An elastic film, comprising a blend, said blend comprising: a continuous phase of at least one propylene copolymer comprising (a) 75-90 wt. % propylene derived units and (b) ethylene and/or alpha-olefin units, said alpha-olefin derived units comprising from 4 to 10 carbon atoms, said ethylene and/or alpha-olefin derived units comprising from 10-25 wt. % of the at least one propylene copolymer, said at least one propylene copolymer comprising a heat of fusion of from > 4 J/g to < 40 J/g, a triad tacticity > 75%; and a dispersed phase of at least one polyethylene comprising a density of from >0.860 g/cc to < 0.970 g/cc; wherein said polymer blend comprises a ratio of 500% tensile modulus of said blend to 500 % tensile modulus of said at least one propylene copolymer, unblended, of < 1.6, and a tension set < 80%.

16. The elastic film of claim 15, wherein said blend comprises a flexural modulus, < 115,000 psi, said at least one propylene copolymer comprises a heptane insolubility < 80% and a narrow composition distribution, such that > 85 wt. % of the at least one propylene polymer may be isolated in thermal fractionation, in 2 adjacent soluble fractions, where each fraction differs less than 20% from the average weight percent ethylene and/or alpha-olefin units of the total at least one propylene copolymer.

17. A molded article comprising a blend composition, said blend composition comprising: a) at least one propylene polymer, said at least one propylene polymer comprising propylene derived units in the range of from ≥ 80 to < 92 weight %, and ethylene and/or α-olefin derived units in the range of > 8 weight % or < 20 weight %, said at least one propylene polymer comprising a melting point of from > 40 °C to < 70°C, and/or a ΔHf in the range of from > 6 J/g to < 60 J/g, a narrow composition distribution, such that > 85 wt. %> of the at least one propylene polymer may be isolated in a thermal fractionation, in 2 adjacent soluble fractions, where each fraction differs less than 20% from the average weight percent ethylene and/or α-olefin derived units of the total at least one propylene polymer, and wherein said at least one propylene polymer comprises a heptane insolubles level of < 80 %; b) at least one ethylene α-olefin polymer, comprising a melting point in the range of from > 70°C to ≤ 125°C, ethylene derived units > 84 mole % and α-olefin derived units of from >1 mole % to <16 mole %, said α-olefin comprising one or more such α-olefin, said α-olefin selected from one of butene- 1, hexene- 1, or octene- 1, or combinations thereof, said at least one ethyleneα-olefin polymer comprising a density > 0.865g/cc or < 0.970 g/cc; wherein said blend composition comprises a ratio of 500%> tensile modulus of said blend composition, to the 500%) tensile modulus of said at least one propylene polymer, unblended, of < 1.5, a tension set of < 80%, wherein said composition comprises a flexural modulus, of < 115,000 psi, wherein the crystallinity of said at least one propylene polymer and said at least one ethylene α-olefin polymer are different.

18. The article of claim 17, wherein said blend composition comprises a hetero phase blend.

19. A hetero phase blend composition, comprising: a) a continuous phase of at least one propylene polymer, said at least one propylene polymer comprising: i) propylene derived units in the range of from > 75 weight percent to < 90 weight percent, and ethylene derived units in the range of from > 10 to < 25 weight percent, based on the total weight of the at least one propylene polymer; ii) a melting point, of from > 35 °C to < 70°C; iii) a ΔHf, of from >1.5 to < 40 J/g; iv) a narrow compositional distribution, such that > 95 wt. % of the at least one propylene polymer may be isolated in a thermal fractionation, in 2 adjacent soluble fractions, where each fraction differs less than 20% from the average weight percent ethylene of the total at least one propylene polymer; v) a heptane insolubles level of < 80 %; b) a dispersed phase of at least one ethylene polymer, said at least one ethylene polymer comprising: i) ethylene present in the range of from 60 mole % - 98 mole %; ii) at least one α-olefin, said at least one α-olefin comprising in the range of from 2 mole %> - 40 mole % of said ethylene polymer, said α-olefin selected from one or more of butene- 1, hexene- 1, or octene- 1, said mole percents based on the total moles of ethylene and at least one α-olefin comprising said at least one ethylene polymer; iii) a melting point of from > 70°C to < 125°C; iv) a density in the range of from > 0.865 to < 0.970 g/cc wherein the flexural modulus of said hetero phase blend composition comprises < 100,000 psi, wherein the ratio of 500%) tensile modulus of the hetero phase blend, to the 500 % tensile modulus of said at least one propylene polymer, unblended is < 1.4, wherein the tension set of said blend is < 80%, and wherein said propylene polymer comprises a crystallinity of one of isotactic or syndiotactic, and said ethylene polymer comprises ethylene crystallinity.

20. A hetero phase blend composition, comprising: a) a continuous phase of at least one first propylene polymer, said at least one first propylene polymer comprising: i) propylene derived units in the range of from > 75 weight percent to < 90 weight percent, and ethylene derived units in the range of from > 25 weight percent to < 10 weight percent, based on the total weight of the at least one first propylene polymer; ii) a melting point, of from > 35°C to < 70°C; iii) a ΔHf, of from >1.5 to < 40 J/g; iv) a narrow composition distribution, such that > 95 wt. % of the at least one propylene polymer may be isolated in a thermal fractionation, in 2 adjacent soluble fractions, where each fraction differs less than 20% from the average weight percent ethylene of the total at least one first propylene polymer; v) a heptane insolubles level of < 80 %; vi) propylene crystallinity selected from one of isotactic or syndiotactic; b) a dispersed phase of at least one second propylene polymer, said at least one second polymer comprising propylene crystallinity selected from one of isotactic or syndiotactic, said crystallinity of said at least one second propylene polymer being different from the crystallinity of said at least one first propylene polymer, wherein the flexural modulus of said hetero phase blend composition comprises < 100,000 psi, wherein the ratio of 500% tensile modulus of the hetero phase blend composition, to the 500 % tensile modulus of said at least one first propylene polymer, unblended is ---- 1.4, wherein the tension set of said hetero phase blend composition is < 80%.