(19) United States
`(12) Patent Application Publication (10) Pub. No.: US 2008/0045638 A1
`Chapman et al.
`(43) Pub. Date:
`Feb. 21, 2008
`
`US 2008004563 8A1
`
`(54) PLASTICIZED HETERO-PHASE
`POLYOLEFIN BLENDS
`
`(76)
`
`Inventors.
`
`Bryan R_ Chapman, Annandalea
`NJ (US); Jeflrey Valentage, Royal
`Oak, MI (US); Jared M. Hill,
`Brighton, MI (US); Bruce R.
`Lundmark, Waller, TX (US)
`
`Correspondence Address:
`EXXONMOBIL CHEMICAL COMPANY
`5200 BAYWAY DRIVE: P-0- BOX 2149
`BAYT0WNs TX 77522'2149
`
`(21) App]. No‘;
`
`11/504,447
`
`(22)
`
`Filed:
`
`Aug. 15, 2006
`
`Publication Classification
`
`(51)
`
`Int CL
`C08K 3/26
`
`(2006.01)
`
`(52) U.s. Cl.
`(57)
`
`..................................................... .. 524/425
`ABSTRACT
`
`This invention relates to hetero-phase polyolefin composi-
`tions comprising: a) 30 to 99.7 wt % of a polypropylene-
`based TPO comprising at least 50 wt % propylene and at
`least 10 wt % ethylene, and b) 0.1 to 20 wt % of one or more
`non-functionalized plasticizer, and c) 0.2 to 50 wt % of one
`fin .b
`d
`h
`~
`f h
`~
`~
`d
`132333;? 1) aef; 1)??? o1i“)05n(ig/enii]rEi1§11‘1trIO1oi‘ee §33“ff)S§“§§;32.1
`modulus of 500 MPa or more, and iii) a notched Charpy
`impact strength at —30° C. of l kl/m2 or more or a notched
`Izod impact strength at —l8° C. of 50 J/m or more.
`
`in applications
`These compositions are especially useful
`such as automotive parts that demand both high stiffness and
`high impact touglmess, as well as good processibility during
`fabrication.
`
`PAGE 1 OF 49
`
`BOREALIS EXHIBIT 1016
`
`BOREALIS EXHIBIT 1016
`
`PAGE 1 OF 49
`
`

`
`US 2008/0045638 A1
`
`Feb. 21, 2008
`
`PLASTICIZED HETERO-PHASE
`POLYOLEFIN BLENDS
`
`STATEMENT OF RELATED CASES
`
`[0001] This application relates to U.S. Ser. No. 60/402,665
`filed Aug. 12, 2002; U.S. Ser. No. 10/634,351 filed Aug. 4,
`2003; U.S. Ser. No. 10/640,435 filed Aug. 12, 2003; and
`U.S. Ser. No. 10/782,228 filed Feb. 19, 2004.
`
`FIELD OF THE INVENTION
`
`[0002] This invention relates to hetero-phase polyolefin
`compositions, such as polypropylene-based thermoplastic
`polyolefin compositions,
`for use in the manufacture of
`automotive components, among other uses, and for articles
`made from such compositions.
`
`BACKGROUND OF THE INVENTION
`
`[0003] Multi-phase polyolefin compositions—often con-
`sisting of a “plastic” matrix phase and a “rubber” dispersed
`phase—are used in many applications that require a material
`that is lightweight, tough, stiff, and easily processed. Par-
`ticularly successful in this respect are compositions based on
`a high-modulus polypropylene and a low-modulus polyole-
`fin modifier, which are typically referred to as thermoplastic
`polyolefins, or TPOs. The modifier component has elasto-
`meric characteristics and typically provides impact resis-
`tance, whereas the polypropylene component typically pro-
`vides overall stiffness.
`
`the most common example of a
`[0004] Commercially,
`TPO is a polypropylene impact copolymer (ICP). In an ICP,
`the matrix phase is essentially a propylene homopolymer
`(hPP) or random copolymer (RCP), and the dispersed phase
`is typically an ethylene or propylene copolymer with a
`relatively high comonomer content, traditionally an ethyl-
`ene-propylene rubber
`(EPR). A third phase containing
`mostly comonomer, such as an ethylene homopolymer or
`copolymer (PE), as well as additives such as fillers, may also
`be present.
`[0005] Low-crystallinity ethylene-alpha olefin copoly-
`mers have also been used instead of (or in addition to) EPR
`as the polyolefin modifier (or dispersed phase) in TPOs. The
`most common such ethylene-alpha olefin copolymers are
`so-called plastomers, which are often ethylene-butene, eth-
`ylene-hexene, or ethylene-octene copolymers with densities
`of 0.90 g/cm3 or less.
`[0006] A major market for TPOs is in the manufacture of
`automotive parts, especially exterior parts like bumper fas-
`cia and body side-molding, and interior parts like instrument
`panels and side pillars. These parts, which have demanding
`stiffness and toughness (and, in some cases, uniform surface
`appearance) requirements, are generally made using an
`injection molding process. To increase efficiency and reduce
`costs, manufacturers have sought to decrease melt viscosity,
`decrease molding times, and reduce wall thickness in the
`molds, primarily by turning to high melt flow rate (MFR)
`polypropylenes (MFR greater than about 20, 25, or even 30
`dg/min). However, these high MFR polypropylenes tend to
`be low in molecular weight, and therefore difficult
`to
`toughen, resulting in low impact strength especially at
`sub-ambient temperatures. To achieve a satisfactory balance
`of stiffness, toughness, and processibility, one option is to
`combine a moderate MFR polypropylene, a high content of
`polyolefin modifier (typically EPR and/or plastomer), and a
`
`PAGE 2 OF 49
`
`reinforcing filler. Unfortunately, this approach has limita-
`tions in terms of the maximum MFR that can be achieved
`
`while still meeting the stiffness and touglmess requirements.
`In addition, it can lead to poor surface appearance, in terms
`of the appearance of flow marks (or “tiger stripes”).
`[0007] What is needed is a way to improve the MFR
`characteristics of a TPO without sacrificing its level of
`performance in terms of mechanical properties, including
`impact strength and/or stiffness,
`that are demanded for
`applications like automotive parts. One way to increase
`MFR is to add a low molecular weight compound, such as
`an even higher MFR polypropylene (hPP, RCP, or ICP).
`However,
`this approach compromises
`the balance of
`mechanical properties of the final blend by also lowering its
`sub-ambient impact strength. A fundamental problem is that
`typical TPO’s based on polypropylene are brittle at even
`moderately low temperatures due to its relatively high glass
`transition temperature (~0° C.). Therefore, there is a need for
`a low molecular weight additive that also lowers the glass
`transition temperature of the polypropylene component of a
`TPO. The plasticizers described herein accomplish this
`objective.
`[0008]
`It would be particularly desirable to use a simple
`compound such as a conventional mineral oil as the low
`molecular weight additive for this purpose. After all, such
`compounds are routinely used as process oils or extender
`oils in polyolefin elastomers. However, it has been taught
`that conventional mineral oils, even paraffinic mineral oils,
`impair the properties of polyolefins,
`in particular semi-
`crystalline polyolefins (see WO 01/ 18109 A1 and Chemical
`Additives for the Plastics Industry, Radian Corp., 1987, p.
`107-116). Indeed, such compounds are often detrimental to
`semicrystalline polypropylene, in that they migrate to the
`surface causing parts to become oily (except at very low
`concentrations), or they degrade mechanical properties
`because they fail to depress the glass transition temperature
`effectively. The plasticizers described herein overcome these
`limitations.
`
`[0009] WO 04/014998 discloses blends of polyolefins
`with non-functionalized plasticizers. In particular, Tables 8,
`11, and 21a to 22f describe blends of certain impact copoly-
`mers with certain liquids and/or plasticizers, and Tables 23a
`to 23f describe blends of a certain thermoplastic polyolefin
`composition with certain liquids and/or plasticizers. These
`blends however are unsuitable for automotive TPO appli-
`cations because they do not have the appropriate balance of
`stiffness, toughness, and flow properties.
`[0010]
`Plasticized polyolefin compositions and their appli-
`cations are also described in WO 04/014997 and US 2004/
`260001. Additional references of interest include: U.S. Pat.
`No. 4,132,698, U.S. Pat. No. 4,536,537, U.S. Pat. No.
`4,774,277, JP 09-208761, WO 98/44041, WO 03/48252, and
`US 2004/034148.
`
`comprise
`that
`including compositions
`[0011] TPOs,
`polypropylene and or filler, are described in POLYPROPYLENE
`HANDBOOK, 2ND ED., N. Pasquim, Ed. (Hanser, 2005), p.
`314-330; POLYMER BLENDS, D. R. Paul and C. B. Bucknall,
`Eds. (Wiley-Interscience, 2000), Vol. 2; U.S. Pat. No. 5,681,
`897; U.S. Pat. No. 6,245,856; and U.S. Pat. No. 6,399,707.
`However, the addition of both a filler and a non-function-
`
`PAGE 2 OF 49
`
`

`
`US 2008/0045638 A1
`
`Feb. 21, 2008
`
`alized plasticizer to a polypropylene-based TPO to give an
`improved balance of properties, as described herein, has not
`been previously disclosed.
`
`SUMMARY OF THE INVENTION
`
`[0012] This invention relates to the use of certain of
`hydrocarbon liquids as plasticizers for hetero-phase poly-
`olefin compositions based on polypropylene. Such compo-
`sitions are especially useful in automotive components and
`other applications that demand high stiffness, excellent
`impact touglmess at low temperatures, and good processi-
`bility during fabrication.
`[0013] More specifically, this invention relates to a hetero-
`phase polyolefin composition comprising:
`[0014]
`a) 30 to 99.7 wt % of a polypropylene-based
`TPO comprising at least 50 wt % propylene and at least
`10 wt % ethylene, and
`[0015]
`b) 0.1 to 20 wt % of one or more non-function-
`alized plasticizer(s), and
`[0016]
`c) 0.2 to 50 wt % of one or more filler(s);
`based upon the weight of the composition, and having:
`[0017]
`i) a melt flow rate, 230° C., 2.16 kg, (MFR) of
`5 dg/min or more, and
`[0018]
`ii) a flexural modulus of 500 MPa or more, and
`[0019]
`iii) a notched Charpy impact strength at —30° C.
`of 1 kJ/m2 or more, or a notched Izod impact strength
`at —18° C. of 50 J/m or more.
`
`Definitions
`
`[0020] The following definitions are made for purposes of
`this invention and the claims thereto.
`
`[0021] When a polymer or oligomer is referred to as
`comprising an olefin, the olefin present in the polymer or
`oligomer is the polymerized or oligomerized form of the
`olefin, respectively. The term polymer is meant to encom-
`pass homopolymers and copolymers. The term copolymer
`includes any polymer having two or more different mono-
`mers in the same chain, and encompasses random copoly-
`mers, statistical copolymers, interpolymers, and (true) block
`copolymers.
`[0022] When a polymer blend is said to comprise a certain
`percentage of a monomer, that percentage of monomer is
`based on the total amount of monomer units in all
`the
`
`polymer components of the blend. For example if a blend
`comprises 50 wt % of polymer A, which has 20 wt %
`monomer X, and 50 wt % of a polymer B, which has 10 wt
`% monomer X, the blend comprises 15 wt % of monomer X.
`[0023] A “polymer” has a number-average molecular
`weight (Mn) of 20 kg/mol or more, while an “oligomer” has
`a M" of less than 20 kg/mol. Preferably, a polymer has a M"
`of 40 kg/mol or more (preferably 60 kg/mol or more,
`preferably 80 kg/mol or more, preferably 100 kg/mol or
`more). Preferably, an oligomers has a M" of less than 15
`kg/mol (preferably less than 13 kg/mol, preferably less than
`10 kg/mol, preferably less than 5 kg/mol, preferably less
`than 4 kg/mol, preferably less than 3 kg/mol, preferably less
`than 2 kg/mol, preferably less than 1 kg/mol).
`[0024] A “polyolefin” is a polymer comprising at least 50
`mol % of one or more olefin monomers. Preferably, a
`polyolefin comprises at least 60 mol % (preferably at least
`70 mol %, preferably at least 80 mol %, preferably at least
`90 mol %, preferably at least 95 mol %, preferably 100 mol
`%) of one or more olefin monomers, preferably 1-olefins,
`
`PAGE 3 OF 49
`
`having carbon numbers of 2 to 20 (preferably 2 to 16,
`preferably 2 to 10, preferably 2 to 8, preferably 2 to 6).
`Preferably, a polyolefin has an Mn of 20 kg/mol or more,
`preferably 40 kg/mol or more (preferably 60 kg/mol or
`more, preferably 80 kg/mol or more, preferably 100 kg/mol
`or more).
`[0025] An “isotactic” polyolefin has at least 10% isotactic
`pentads, a “highly isotactic” polyolefin has at least 50%
`isotactic pentads, and a “syndiotactic” polyolefin has at least
`10% syndiotactic pentads, according to analysis by 13C-
`NMR. Preferably isotactic polymers have at
`least 20%
`(preferably at least 30%, preferably at least 40%) isotactic
`pentads. A polyolefin is “atactic” if it has less than 5%
`isotactic pentads and less than 5% syndiotactic pentads.
`[0026] The terms “polypropylene” and “propylene poly-
`mer” mean a polyolefin comprising at
`least 50 mol %
`propylene units and having less than 35 mol % ethylene
`units. Preferably the “polypropylene” and “propylene poly-
`mer” comprise at least 60 mol % (preferably at least 70 mol
`%, preferably at least 80 mol %, preferably at least 90 mol
`%, preferably at least 95 mol %, preferably 100 mol %)
`propylene units; and have less than 35 mol % ethylene units.
`While propylene-rich ethylene/propylene copolymers are
`generically a class of propylene copolymer, a special dis-
`tinction is made herein for the composition range commonly
`associated with EP Rubber, as defined below. The comono-
`mers in a propylene copolymer are preferably chosen from
`among ethylene and C4 to C20 olefins (preferably ethylene
`and C4 to C8 1-olefins). The term “polypropylene” is meant
`to encompass isotactic polypropylene (iPP), highly isotactic
`polypropylene,
`syndiotactic
`polypropylene
`(sPP),
`homopolymer polypropylene (hPP, also called propylene
`homopolymer or homopolypropylene), and so-called ran-
`dom copolymer polypropylene (RCP, also called propylene
`random copolymer). Herein, an RCP is specifically defined
`to be a copolymer of propylene and 1 to 10 wt % of an olefin
`chosen from ethylene and C4 to C8 1-olefins. Preferably, the
`olefin comonomer in an RCP is ethylene or 1-butene,
`preferably ethylene.
`[0027] The terms “polyethylene” and “ethylene polymer”
`mean a polyolefin comprising at least 50 mol % ethylene
`units and having less than 15 mol % propylene units.
`Preferably the “polyethylene” and “ethylene polymer” com-
`prise at least 60 mol % (preferably at
`least 70 mol %,
`preferably at least 80 mol %, even preferably at least 90 mol
`%, even preferably at least 95 mol % or preferably 100 mole
`%) ethylene units; and have less than 15 mol % propylene
`units. While ethylene-rich ethylene/propylene copolymers
`are generically a class of ethylene copolymer, a special
`distinction is made herein for the composition range com-
`monly associated with EP Rubber, as defined below. The
`comonomers in an ethylene copolymer are preferably cho-
`sen from C3 to C20 olefins (preferably C3 to C8 1-olefins). An
`“ethylene elastomer” is an ethylene copolymer having a
`density of less than 0.86 g/cm3 . An “ethylene plastomer” (or
`simply a “plastomer”) is an ethylene copolymer having a
`density of 0.86 to 0.91 g/cm3. A “low density polyethylene”
`is an ethylene polymer having a density of more than 0.91
`g/cm3 to less than 0.94 g/cm3; this class of polyethylene
`includes copolymers made using a heterogeneous catalysis
`process (often identified as linear low density polyethylene,
`LLDPE) and homopolymers or copolymers made using a
`high-pressure/free radical process
`(often identified as
`
`PAGE 3 OF 49
`
`

`
`US 2008/0045638 A1
`
`Feb. 21, 2008
`
`LDPE). A “high density polyethylene” (“HDPE”) is an
`ethylene polymer having a density of 0.94 g/cm3 or more.
`[0028] The term “EP Rubber” means a copolymer of
`ethylene and propylene, and optionally one or more diene
`monomer(s), where the ethylene content is from 35 to 85
`mol %, the total diene content is 0 to 5 mol %, and the
`balance is propylene with a minimum propylene content of
`15 mol %.
`
`[0029] The term “hetero-phase” refers to the presence of
`two or more morphological phases in a blend of two or more
`polymers, where each phase comprises a different ratio of
`the polymers as a result of partial or complete immiscibility
`(i.e., thermodynamic incompatibility). A common example
`is a morphology consisting of a “matrix” (continuous) phase
`and at
`least one “dispersed” (discontinuous) phase. The
`dispersed phase takes the form of discrete domains (par-
`ticles) distributed within the matrix (or within other phase
`domains,
`if there are more than two phases). Another
`example is a co-continuous morphology, where two phases
`are observed but it is unclear which is the continuous phase
`and which is the discontinuous phase. The presence of
`multiple phases is determined using microscopy techniques,
`e.g., optical microscopy,
`scanning electron microscopy
`(SEM), or atomic force microscopy (AFM); or by the
`presence of two glass transition peaks in a dynamic
`mechanical analysis (DMA) experiment;
`in the event of
`disagreement among these methods, the AFM determination
`shall be used.
`
`[0030] A “thermoplastic polyolefin” (TPO) is a specific
`type of hetero-phase polyolefin composition. These are
`blends of a high-crystallinity “base polyolefin” (typically
`having a melting point of 100° C. or more) and a low-
`crystallinity or amorphous “polyolefin modifier” (typically
`having a Tg of —20° C. or less). The hetero-phase morphol-
`ogy consists of a matrix phase comprised primarily of the
`base polyolefin, and a dispersed phase (which is not, or only
`modestly, cross-linked) comprised primarily of the polyole-
`fin modifier. Thus, the matrix phase has a modulus that is
`higher, often substantially higher, than that of the dispersed
`phase. TPO compositions may also comprise components
`such as fillers, additives, and other useful compounding
`ingredients.
`[0031] A “polypropylene-based thermoplastic polyolefin”
`(or equivalently, a “polypropylene-based TPO”) is a specific
`type of TPO, in that the matrix phase comprises primarily a
`high-crystallinity polypropylene having a melting point (Tm)
`of 100° C. or more, and the dispersed phase comprises
`primarily a polyolefin having a glass transition temperature
`(Tg) of —20° C. or less. Preferably, the matrix phase com-
`prises primarily homopolymer polypropylene (hPP) and/or
`random copolymer polypropylene (RCP) with relatively low
`comonomer content (less than 5 wt %), and has a melting
`point of 110° C. or more (preferably 120° C. or more,
`preferably 130° C. or more, preferably 140° C. or more,
`preferably 150° C. or more, preferably 160° C. or more).
`Preferably, the dispersed phase comprises primarily one or
`more ethylene copolymer(s) with relatively high comono-
`mer content (at least 5 wt %, preferably at least 10 wt %);
`and has a Tg of —30° C. or less (preferably —40° C. or less,
`preferably —50° C. or less).
`[0032] A “polypropylene impact copolymer” (herein sim-
`ply referred to as an “impact copolymer” (lCP)) is a specific
`type of polypropylene-based TPO, comprising 60 to 95 wt %
`of (A) hPP or RCP with a Tm of 120° C. or more, and 5 to
`
`PAGE 4 OF 49
`
`40 wt % of (B) propylene copolymer with a Tg of —30° C.
`or less. The morphology of an ICP is such that the matrix
`phase is comprised primarily of component (A) while the
`dispersed phase is comprised primarily of component (B).
`Preferably, the ICP comprises only two monomers: propy-
`lene and a single comonomer chosen from among ethylene
`and C4 to C8 1-olefins (preferably ethylene or 1-butene,
`preferably ethylene). Preferably, the (A) component has a
`Tm of 120° C. or more (preferably 130° C. or more, prefer-
`ably 140° C. or more, preferably 150° C. or more, preferably
`160° C. or more). Preferably,
`the (B) component is EP
`Rubber. Preferably, the (B) component has a Tg of —40° C.
`or less (preferably —50° C.).
`[0033] An “in-situ lCP” is a specific type of ICP which is
`a reactor blend of the (A) and (B) components of an ICP,
`meaning (A) and (B) were made in separate reactors (or
`reactions zones) physically connected in series, with the
`effect that an intimately mixed final product is obtained in
`the product exiting the final reactor (or reaction zone).
`Typically,
`the components are produced in a sequential
`polymerization process, wherein (A) is produced in a first
`reactor is transferred to a second reactor where (B)
`is
`produced and incorporated as domains into the (A) matrix.
`There may also be a minor amount of a third component (C),
`produced as a byproduct during this process, comprising
`primarily the non-propylene comonomer (e.g., (C) will be an
`ethylene polymer if ethylene is used as the comonomer). In
`the literature, especially in the patent literature, an in-situ
`ICP is sometimes identified as “reactor-blend lCP” or a
`
`“block copolymer”, although the latter term is misleading
`since there is at best only a very small fraction of molecules
`that are (A)-(B) copolymers.
`[0034] An “ex-situ lCP” is a specific type of ICP which is
`a physical blend of (A) and (B), meaning (A) and (B) were
`synthesized independently and then subsequently blended
`typically using a melt-mixing process, such as an extruder.
`An ex-situ ICP is distinguished by the fact that (A) and (B)
`are collected in solid form after exiting their respective
`synthesis processes, and then combined; whereas for an
`in-situ ICP, (A) and (B) are combined within a common
`synthesis process and only the blend is collected in solid
`form.
`
`For purposes of this invention, TPO compositions
`[0035]
`include those hetero-phase polyolefins generally
`do not
`referred to as “Thermoplastic Vulcanizates” (TPVs). These
`are blends of a high-crystallinity polypropylene and a low-
`crystallinity or amorphous polyolefin modifier (often an
`ethylene-propylene elastomer) which is highly cross-linked
`(vulcanized) through the use of a cross-linking agent to
`provide a rubber-like resilience to the composition, and
`optionally other compounding ingredients; see, for example,
`U.S. Pat. No. 4,311,628. The polyolefin modifier in hetero-
`phase polyolefin compositions of the instant invention are
`not crosslinked to an appreciable extent. That is, the so-
`called “gel content” of the composition is low, so that
`preferably less than 50 wt %, preferably less than 40 wt %,
`preferably less than 30 wt %, preferably less than 20 wt %,
`preferably less than 10 wt %, preferably less than 5 wt %,
`preferably 0%) of the polyolefin modifier is insoluble in
`boiling xylene.
`[0036] A “liquid” is defined to be a material that flows at
`room temperature, having a pour point of less than +20° C.
`and a kinematic viscosity at 25° C. of 30,000 cSt or less.
`
`PAGE 4 OF 49
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`

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`US 2008/0045638 A1
`
`Feb. 21, 2008
`
`[0037] The term “paraffin” refers to saturated hydrocar-
`bons, including normal paraffins, branched paraffins, isopar-
`affins, cycloparaffins, and blends thereof, and may be
`derived synthetically or from refined crude oil by means
`known in the art. More specifically, the following terms have
`the indicated meanings: “isoparaffins” are branched chain-
`type saturated hydrocarbons (i.e., branched alkanes, having
`at
`least one tertiary or quaternary carbon atom), which
`possess at least one C1 to C8 (more commonly C1 to C10)
`alkyl branch along at least a portion of each chain; “normal
`paraffins” are un-branched chain-type saturated hydrocar-
`bons
`(i.e., normal alkanes); and “cycloparaffins” (also
`known as “naphthenes”) are cyclic (mono-ring and/or multi-
`ring) saturated hydrocarbons and branched cyclic saturated
`hydrocarbons. For each class of paraffin, various structural
`isomers will typically be present for each carbon number.
`Unsaturated hydrocarbons include alkenes (olefins, diole-
`fins, etc.), alkynes, and “aromatics” (unsaturated mono-ring
`and/or multi-ring cyclic moieties, including branched cyclic
`unsaturated hydrocarbons).
`[0038] The term “mineral oil” includes any hydrocarbon
`liquid of lubricating viscosity (i.e., a kinematic viscosity at
`100° C. of 1 cSt or more) derived from petroleum crude oil
`and subjected to one or more refining and/or hydroprocess-
`ing steps (such as fractionation, hydrocracking, dewaxing,
`isomerization, and hydrofinishing) to purify and chemically
`modify the components to achieve a final set of properties.
`Such “refined” oils are in contrast to “synthetic” oils, which
`are manufactured by combining monomer units using cata-
`lysts and/or heat. In the lubricant industry, refined “bas-
`estocks” (which are mineral oils) are commonly divided into
`three categories based on their properties, as follows:
`
`Category
`
`Saturates
`
`Sulfur
`
`Viscosity Index
`
`Group I
`Group II
`Group III
`
`<90 wt % and/or
`390 wt % and
`390 wt % and
`
`>0.03 wt % and
`§0.03 wt % and
`§0.03 wt % and
`
`80—119
`80—119
`3120
`
`However, even if a mineral oil is not specifically identified
`by one of these basestocks classification, it is still possible
`to categorize it using this scheme. Accordingly, herein, a
`“Group III Mineral Oil” is defined to be a mineral oil having
`a viscosity index of 120 or more, whereas a “Group III
`basestock” is defined according to the above table; therefore,
`any Group III basestock will also be a Group III Mineral Oil,
`but the opposite is not necessarily true.
`[0039]
`In the polymer industry, mineral oils are often
`called “process oils” (or “extender oils”). A common clas-
`sification system for process oils is to identify them as either
`“paraffinic”, “naphthenic”, or “aromatic” mineral (or pro-
`cess or extender) oils based on the relative content of
`paraffinic, naphthenic, and aromatic moieties (see Typical in
`the table below). Herein,
`the three common classes are
`defined based on the compositions described under Defini-
`tions in the table below:
`
`PAGE 5 OF 49
`
`Mineral Oil
`
`Type
`Paraflinic
`Naphthenic
`Aromatic
`
`Typical
`
`Definitions
`
`CA
`CN
`CP
`60—80% 20410% 0—10%
`40—55% 40—55%
`6—15%
`35—55% 10—35% 3040%
`
`CP
`2 60%
`
`CA
`CN
`<20%
`<40%
`340% <20%
`320%
`
`where CP, CN, and CA indicate the percentage of carbons in
`parafi‘inic chain-like (i.e.,
`isoparaffinic and normal paraf-
`finic) structures, naphthenic (i.e., saturated ring) structures,
`and aromatic (i.e., unsaturated ring) structures, respectively.
`[0040] The term “substantially absent” means that the
`compounds in question are not added deliberately to the
`compositions and, if present, are present at less than 1 wt %,
`based upon the total weight of the composition. Preferably,
`the compounds in question are present at less than 0.5 wt %
`(preferably less than 0.1 wt %, preferably less than 0.05 wt
`%, preferably less than 0.01 wt %, preferably less than 0.001
`wt %), based upon the total weight of the composition.
`[0041]
`For purpose of this invention and the claims
`thereto, unless otherwise noted, physical and chemical prop-
`erties described herein are measured using the test methods
`described under the Experimental Methods section.
`
`DETAILED DESCRIPTION OF THE
`INVENTION
`
`[0042] This invention relates to plasticized hetero-phase
`polyolefin compositions comprising a polypropylene-based
`TPO, one or more non-functionalized plasticizers, and one
`or more filler.
`
`(NFP) com-
`[0043] The non-functionalized plasticizer
`pounds of the present invention are hydrocarbon liquids with
`certain characteristics as described herein. We discovered
`
`that addition of one or more NFP improves the overall
`performance of polypropylene-based TPO compositions that
`meet the stringent array of mechanical property require-
`ments for automotive (and other) applications. In particular,
`these compositions exhibit better processibility than can be
`achieved using previous formulation approaches. Generally,
`the compositions comprise a polypropylene-based TPO, an
`NFP, and a filler, and optionally additives.
`[0044] More specifically, this invention relates to a hetero-
`phase polyolefin composition comprising:
`[0045]
`a) 30 to 99.7 wt % of a polypropylene-based
`TPO comprising at least 50 wt % propylene and at least
`10 wt % ethylene, and
`[0046]
`b) 0.1 to 20 wt % of one or more non-function-
`alized plasticizer, and
`[0047]
`c) 0.2 to 50 wt % of one or more filler;
`based upon the weight of the composition, and having:
`[0048]
`i) an MFR of 5 dg/min or more, and
`[0049]
`ii) a flexural modulus of 500 MPa or more, and
`[0050]
`iii) a notched Charpy impact strength at —30° C.
`of 1 kJ/m2 or more, and/or a notched Izod impact
`strength at —18° C. of 50 J/m or more.
`[0051] The polypropylene-based TPO may be an impact
`copolymer (especially an in-situ ICP), or it may be a
`physical blend of an ICP with a plastomer and/or ethylene-
`propylene rubber (EP Rubber), or it may be a physical blend
`of a propylene polymer (especially a homopolymer polypro-
`pylene (hPP) or a random copolymer polypropylene (RCP))
`
`PAGE 5 OF 49
`
`

`
`US 2008/0045638 A1
`
`Feb. 21, 2008
`
`with a plastomer and/or EP Rubber. Preferred polymeric
`components are described more fully below. In a preferred
`embodiment,
`the polypropylene-based TPO comprises a
`matrix having a melting point (Tm) of 110° C. or more
`(preferably 120° C. or more, preferably 125° C. or more,
`preferably 130° C. or more, preferably 140° C. or more,
`preferably 150° C. or more, preferably 160° C. or more). In
`another preferred embodiment,
`the polypropylene-based
`TPO comprises a dispersed phase having a glass transition
`temperature (Tg) of —20° C. or less (preferably —25° C. or
`less, preferably —30° C. or less, preferably —35° C. or less,
`preferably —40° C. or less, preferably —45° C. or less,
`preferably —50° C. or less, preferably —55° C. or less).
`[0052] The non-functional plasticizer (NFP) may be a
`PAO oligomer, or it may be a Group III Mineral Oil, or it
`may be a GTL basestock, or it may be an Exceptional
`Paraffinic Process Oil. Preferably, the NFP has a kinematic
`viscosity at 100° C. of5 cSt or more, a viscosity index of 100
`or more, a pour point of —20° C. or less, a specific gravity
`less than 0.86, and a flash point greater than 200° C.
`Preferred NFPs are described more fully below.
`[0053] The filler may be inorganic mineral particulates,
`inorganic fibers, or engineering thermoplastic fibers. Pre-
`ferred fillers are described more fully below.
`
`Hetero-Phase Polyolefin Composition
`
`this invention relates to a
`In one embodiment,
`[0054]
`hetero-phase polyolefin composition comprising:
`[0055]
`a) 30 to 99.7 wt % (preferably 35 to 95 wt %,
`preferably 40 to 90 wt %, preferably 45 to 85 wt %) of
`a polypropylene-based TPO,
`[0056]
`b) 0.1 to 20 wt % (preferably 0.5 to 15 wt %,
`preferably 1 to 10 wt %, preferably 1.5 to 5 wt %) of
`one or more NFP(s), and
`[0057]
`c) 0.2 to 50 wt % (preferably 0.5 to 40 wt %,
`preferably 1 to 30 wt %, preferably 5 to 20 wt %) of one
`or more filler(s),
`based upon the weight of the composition; and having
`[0058]
`i) a melt flow rate of 5 dg/min or more (prefer-
`ably 10 dg/min or more, preferably 15 to 400 dg/min,
`preferably 20 to 300 dg/min, preferably 30 to 200
`dg/min or more, preferably 35 to 100 dg/min),
`[0059]
`ii) a flexural modulus of 500 MPa or more
`(preferably 800 MPa or more, preferably 900 to 3500
`MPa, preferably 1000 to 3000 MPa, preferably 1100 to
`2500 MPa), and
`[0060]
`iii) a notched Charpy impact strength at —30° C.
`of 1 kJ/m2 or more (preferably 2 kJ/m2 or more,
`preferably 2.5 to 15 kJ/m2, preferably 3 to 12 k]/m2),
`and/or a notched Izod impact strength at —18° C. of 50
`J/m or more (preferably 60 J/m or more, preferably 70
`to 500 J/m, preferably 80 to 400 J/m, preferably 90 to
`300 J/m, preferably 100 to 200 J/m);
`where the polypropylene-based TPO comprises at least 50
`wt % (preferably at least 55 wt %, preferably at least 60 wt
`%, preferably at least 65 wt %) propylene and at least 10 wt
`% (preferably at least 15 wt %, preferably at least 20 wt %,
`preferably at least 25 wt %) ethylene, based on the total
`weight of the propylene based-TPO. The polypropylene-
`based TPO may comprise one or more ICP(s); or one or
`more propylene polymer and one or more ethylene copoly-
`mer and/or EP Rubber; or one or more ICP and one or more
`propylene polymer and one or more ethylene copolymer
`and/or EP Rubber.
`
`PAGE 6 OF 49
`
`In another embodiment, this invention relates to a
`[0061]
`hetero-phase polyolefin composition comprising:
`[0062]
`a) 30 to 99.7 wt % (preferably 35 to 95 wt %,
`preferably 40 to 90 wt %, preferably 45 to 85 wt %) of
`one or more ICP(s),
`[0063]
`b) 0.1 to 20 wt % (preferably 0.5 to 15 wt %,
`preferably 1 to 10 wt %, preferably 1.5 to 5 wt %) of
`one or more NFP(s), and
`[0064]
`c) 0.2 to 50 wt % (preferably 0.5 to 40 wt %,
`preferably 1 to 30 wt %, preferably 5 to 20 wt %) of one
`or more filler(s),
`based upon the weight of the composition; and having
`[0065]
`i) a melt flow rate of 5 dg/min or more (prefer-
`ably 10 dg/min or more, preferably 15 to 400 dg/min,
`preferably 20 to 300 dg/min, preferably 30 to 200
`dg/min or more, preferably 35 to 100 dg/min),
`[0066]
`ii) a flexural modulus of 500 MPa or more
`(preferably 800 MPa or more, preferably 900 to 3500
`MPa, preferably 1000 to 3000 MPa, preferably 1100 to
`2500 MPa), and
`[0067]
`iii) a notched Charpy impact strength at —30° C.
`of 1 kJ/m2 or more (preferably 2 kJ/m2 or more,
`preferably 2.5 to 15 kJ/m2, preferably 3 to 12 k]/m2),
`and/or a notched Izod impact strength at —18° C. of 50
`J/m or more (preferably 60 J/m or more, preferably 70
`to 500 J/m, preferably 80 to 400 J/m, preferably 90 to
`300 J/m, preferably 100 to 200 J/m);
`where the combination of ICP(s) comprises at least 50 wt %
`(preferably at least 55 wt %, preferably at least 60 wt %,
`preferably at least 65 wt %) propylene and at least 10 wt %
`(preferably at least 15 wt %, preferably at least 20 wt %,
`preferably at least 25 wt %) ethylene, based