Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F210/00—Copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond
  • C08F210/16—Copolymers of ethene with alpha-alkenes, e.g. EP rubbers
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F210/00—Copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond
  • C08F210/04—Monomers containing three or four carbon atoms
  • C08F210/06—Propene
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F4/00—Polymerisation catalysts
  • C08F4/42—Metals; Metal hydrides; Metallo-organic compounds; Use thereof as catalyst precursors
  • C08F4/44—Metals; Metal hydrides; Metallo-organic compounds; Use thereof as catalyst precursors selected from light metals, zinc, cadmium, mercury, copper, silver, gold, boron, gallium, indium, thallium, rare earths or actinides
  • C08F4/60—Metals; Metal hydrides; Metallo-organic compounds; Use thereof as catalyst precursors selected from light metals, zinc, cadmium, mercury, copper, silver, gold, boron, gallium, indium, thallium, rare earths or actinides together with refractory metals, iron group metals, platinum group metals, manganese, rhenium technetium or compounds thereof
  • C08F4/62—Refractory metals or compounds thereof
  • C08F4/639—Component covered by group C08F4/62 containing a transition metal-carbon bond
  • C08F4/63908—Component covered by group C08F4/62 containing a transition metal-carbon bond in combination with an ionising compound other than alumoxane, e.g. (C6F5)4B-X+
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F4/00—Polymerisation catalysts
  • C08F4/42—Metals; Metal hydrides; Metallo-organic compounds; Use thereof as catalyst precursors
  • C08F4/44—Metals; Metal hydrides; Metallo-organic compounds; Use thereof as catalyst precursors selected from light metals, zinc, cadmium, mercury, copper, silver, gold, boron, gallium, indium, thallium, rare earths or actinides
  • C08F4/60—Metals; Metal hydrides; Metallo-organic compounds; Use thereof as catalyst precursors selected from light metals, zinc, cadmium, mercury, copper, silver, gold, boron, gallium, indium, thallium, rare earths or actinides together with refractory metals, iron group metals, platinum group metals, manganese, rhenium technetium or compounds thereof
  • C08F4/62—Refractory metals or compounds thereof
  • C08F4/639—Component covered by group C08F4/62 containing a transition metal-carbon bond
  • C08F4/6392—Component covered by group C08F4/62 containing a transition metal-carbon bond containing at least one cyclopentadienyl ring, condensed or not, e.g. an indenyl or a fluorenyl ring
  • C08F4/63922—Component covered by group C08F4/62 containing a transition metal-carbon bond containing at least one cyclopentadienyl ring, condensed or not, e.g. an indenyl or a fluorenyl ring containing at least two cyclopentadienyl rings, fused or not
  • C08F4/63927—Component covered by group C08F4/62 containing a transition metal-carbon bond containing at least one cyclopentadienyl ring, condensed or not, e.g. an indenyl or a fluorenyl ring containing at least two cyclopentadienyl rings, fused or not two cyclopentadienyl rings being mutually bridged
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L23/00—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers
  • C08L23/02—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers not modified by chemical after-treatment
  • C08L23/10—Homopolymers or copolymers of propene
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F4/00—Polymerisation catalysts
  • C08F4/42—Metals; Metal hydrides; Metallo-organic compounds; Use thereof as catalyst precursors
  • C08F4/44—Metals; Metal hydrides; Metallo-organic compounds; Use thereof as catalyst precursors selected from light metals, zinc, cadmium, mercury, copper, silver, gold, boron, gallium, indium, thallium, rare earths or actinides
  • C08F4/60—Metals; Metal hydrides; Metallo-organic compounds; Use thereof as catalyst precursors selected from light metals, zinc, cadmium, mercury, copper, silver, gold, boron, gallium, indium, thallium, rare earths or actinides together with refractory metals, iron group metals, platinum group metals, manganese, rhenium technetium or compounds thereof
  • C08F4/62—Refractory metals or compounds thereof
  • C08F4/64—Titanium, zirconium, hafnium or compounds thereof
  • C08F4/659—Component covered by group C08F4/64 containing a transition metal-carbon bond
  • C08F4/65908—Component covered by group C08F4/64 containing a transition metal-carbon bond in combination with an ionising compound other than alumoxane, e.g. (C6F5)4B-X+
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2205/00—Polymer mixtures characterised by other features
  • C08L2205/02—Polymer mixtures characterised by other features containing two or more polymers of the same C08L -group
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2314/00—Polymer mixtures characterised by way of preparation
  • C08L2314/06—Metallocene or single site catalysts

Definitions

• This invention relates to propylene/olefin copolymers (PO) having unique properties described herein as a relationship of mole % olefin to: 1) isotactic index, 2) % meso propylene triad, and 3) glass transition temperature.
• the olefins include C 2 , C 4 -C 20 alpha-olefins, the most preferred olefin being ethylene (C 2 ).
• the isotactic index of this invention's copolymers is equal to -0.0224O + A wherein O is the mole % olefin present, A is a number from 66 to 89 and the isotactic index is greater than 0.
• the propylene tacticity of this invention's polymers is also described by % meso triad equal to -0.4492EO + B wherein O is the mole % olefin present, B is a number from 93 to 100, and the % meso triad is less than 95%, preferably less than 93%, even more preferably less than 90%. Additionally, the copolymers of this invention have a glass transition temperature equal to -1.1082O -
• the PO copolymers of this invention are distinguished over prior art PO copolymers by their unique crystalline characteristics coupled with elastomeric properties which make them useful in a variety of applications such as: thermoplastic elastomers (TPEs), impact modifiers and compatibilizers in thermoplastic olefins (TPOs), in elastic fibers and films, in dynamically vulcanized alloys (DVAs), as curable elastomers, in adhesives, in polyvinyl chloride (PVC) replacements, and in viscosity modifiers.
• TPEs thermoplastic elastomers
• DVAs dynamically vulcanized alloys
• PVC polyvinyl chloride
• the PO copolymers of this invention may contain small quantities of a non-conjugated diene to aid in the vulcanization and other chemical modification.
• a non-conjugated diene to aid in the vulcanization and other chemical modification.
• copolymer is intended to include both polymers formed from ethylene and one or more alpha-olefins and polymers formed from ethylene, one or more alpha-olefins, and one or more non-conjugated dienes.
• the preferred non-conjugated diene is selected from the group consisting of those monomers useful for vulcanization of ethylene-propylene rubbers, such as, but not limited to,
• the amount of diene is preferably less than 10 wt % and most preferably less than 5 wt %.
• the polymers of this invention may be prepared by polymerizing a C 2 , C 4 -
• C 20 alpha olefin preferably ethylene and propylene in the presence of a chiral metallocene catalyst with an activator and optional scavenger.
• EP copolymers have been used to make ethylene propylene (EP) copolymers.
• European Patent Application 128 046 discloses making an EP copolymer with at least two non-chiral metallocenes.
• achiral metallocenes are inherently incapable of making copolymers having an isotactic index greater than 0 and having the other unique crystalline characteristics coupled with elastomeric properties of EP copolymers of this invention.
• EP 0 374 695 discloses the preparation of EP copolymers having an isotactic index greater than 0 using a chiral metallocene catalyst with an alumoxane co- catalyst.
• the copolymers of the present invention have an isotactic index equal to -0.0224Et + A wherein Et is the mole % ethylene present, A is a number from 66 to 89, and the isotactic index is greater than 0.
• Et is the mole % ethylene present
• A is a number from 66 to 89
• the isotactic index is greater than 0.
• This relationship of mole % ethylene to isotactic index is absent in EP 0 374 695 as seen by figure 1.
• isotactic index of EP copolymers of this invention is significantly lower than that of EP copolymers of EP 0 374 695.
• the low isotactic index of EP copolymers of this invention is the key to their excellent elastomeric properties.
• U.S. Patent No. 5,504,172 discloses the preparation of EP copolymers having a high % meso triad tacticity of propylene units, however, % meso triad tacticity of propylene units of the copolymers of the present invention is significantly low and equal to -0.4492Et + B wherein Et is the mole % ethylene present, B is a number from 93 to 100, and the % meso triad is less than 95%.
• Et is the mole % ethylene present
• B is a number from 93 to 100
• the % meso triad is less than 95%.
• This relationship of mole % ethylene to triad tacticity is seen in the polymers of U.S. Patent No. 5,504,172 as shown by figure 2.
• Figure 1 is a graph depicting mole % ethylene on the x-axis and isotactic index on the y-axis.
• Figure 2 is a graph depicting mole % ethylene on the x-axis and % meso propylene triad on the y-axis.
• Figure 3 is a graph depicting mole % ethylene on the x-axis and glass transition temperature on the y-axis.
• the catalyst system described below useful for making the PO copolymers of this invention is a metallocene with a non-coordinating anion (NCA) activator, and optionally a scavenging compound.
• Polymerization is conducted in a solution, slurry or gas phase, preferably in solution phase.
• the polymerization can be performed in a single- or multiple-reactor process.
• a slurry or solution polymerization process can utilize sub- or superatmospheric pressures and temperatures in the range of from -25 °C to 110 °C.
• a suspension of solid, paniculate polymer is formed in a liquid polymerization medium to which ethylene, alpha-olefin comonomer, hydrogen and catalyst are added.
• the liquid medium serves as a solvent for the polymer.
• the liquid employed as the polymerization medium can be an alkane or a cycloalkane, such as butane, pentane, hexane, or cylclohexane, or an aromatic hydrocarbon, such as toluene, ethylbenzene or xylene.
• liquid monomer can also be used.
• the medium employed should be liquid under the conditions of the polymerization and relatively inert.
• hexane or toluene is employed for solution polymerization. Gas phase polymerization processes are described in U.S. Patent Nos.
• the catalyst may be supported on any suitable particulate material or porous carrier such as polymeric supports or inorganic oxide for example silica, alumina or both.
• metallocene and "metallocene catalyst precursor” are terms known in the art to mean compounds possessing a Group IV, V, or VI transition metal M, with a cyclopentadienyl (Cp) ligand or ligands which may be may be substituted, at least one non-cyclopentadienyl-derived ligand X, and zero or one heteroatom-containing ligand Y, the ligands being coordinated to M and corresponding in number to the valence thereof.
• Cp cyclopentadienyl
• the metallocene catalyst precursors are generally require activation with a suitable co-catalyst (referred to as activator) in order to yield an active metallocene catalyst which refers generally to an organometallic complex with a vacant coordination site that can coordinate, insert, and polymerize olefins.
• activator a suitable co-catalyst
• active metallocene catalyst which refers generally to an organometallic complex with a vacant coordination site that can coordinate, insert, and polymerize olefins.
• Preferable metallocenes are cyclopentadienyl (Cp) complexes which have two Cp ring systems for ligands.
• the Cp ligands preferably form a bent sandwich complex with the metal and are preferably locked into a rigid configuration through a bridging group.
• These cyclopentadienyl complexes have the general formula:
• Cp 1 of ligand (Cp'R' and Cp 2 of ligand (Cp 2 R 2 p ) are preferably the same, R 1 and R 2 each is, independently, a halogen or a hydrocarbyl, halocarbyl, hydrocarbyl-substituted organometalloid or halocarbyl-substituted organometalloid group containing up to 20 carbon atoms, m is preferably 1 to 5, p is preferably 1 to 5, and preferably two R 1 and/or R 2 substituents on adjacent carbon atoms of the cyclopentadienyl ring associated there with can be joined together to form a ring containing from 4 to 20 carbon atoms, R 3 is a bridging group, n is the number of atoms in the direct chain between the two ligands and is preferably 1 to 8, most preferably 1 to 3, M is a transition metal having a valence of from 3 to 6, preferably from group 4, 5, or 6 of the periodic
• non-coordinating anion means an anion which either does not coordinate to said transition metal cation or which is only weakly coordinated to said cation thereby remaining sufficiently labile to be displaced by a neutral Lewis base.
• “Compatible” non-coordinating anions are those which are not degraded to neutrality when the initially formed complex decomposes. Further, the anion will not transfer an anionic substituent or fragment to the cation so as to cause it to form a neutral four coordinate metallocene compound and a neutral by-product from the anion.
• Non-coordinating anions useful in accordance with this invention are those which are compatible, stabilize the metallocene cation in the sense of balancing its ionic charge, yet retain sufficient lability to permit displacement by an ethylenically or acetylenically unsaturated monomer during polymerization.
• the anions useful in this invention are preferably large or bulky in the sense of sufficient molecular size to largely inhibit or prevent neutralization of the metallocene cation by Lewis bases other than the polymerizable monomers that may be present in the polymerization process.
• the anion will have a molecular size of greater than or equal to 4 angstroms.
• ionic catalysts for coordination polymerization comprised of metallocene cations activated by non-coordinating anions appear in the early work in EP-A-0 277 003, EP-A-0 277 004, U.S. Patents 5,198,401 and 5,278,119, and WO 92/00333. These teach a preferred method of preparation wherein metallocenes (bisCp and monoCp) are protonated by an anionic precursors such that an alkyl/hydride group is abstracted from a transition metal to make it both cationic and charge-balanced by the non-coordinating anion.
• ionizing ionic compounds not containing an active proton but capable of producing both the active metallocene cation and a non-coordinating anion is also known. See, EP-A-0 426 637, EP-A- 0 573 403 and U.S. Patent 5,387,568.
• Reactive cations other than Bronsted acids capable of ionizing the metallocene compounds include ferrocenium, triphenylcarbonium, and triethylsilylium cations. Any metal or metalloid capable of forming a coordination complex which is resistant to degradation by water (or other Bronsted or Lewis acids) may be used or contained in the anion of the second activator compound.
• Suitable metals include, but are not limited to, aluminum, gold, platinum and the like.
• Suitable metalloids include, but are not limited to, boron, phosphorus, silicon and the like. The description of non-coordinating anions and precursors thereto of these documents are incorporated by reference for purposes of U.S. Patent Practice.
• An additional method of making the ionic catalysts uses ionizing anionic pre-cursors which are initially neutral Lewis acids but form the cation and anion upon ionizing reaction with the metallocene compounds, for example tris(pentafluorophenyl) boron acts to abstract an alkyl, hydride or silyl ligand to yield a metallocene cation and stabilizing non-coordinating anion, see EP-A-0 427 697 and EP-A-0 520 732.
• Ionic catalysts for addition polymerization can also be prepared by oxidation of the metal centers of transition metal compounds by anionic precursors containing metallic oxidizing groups along with the anion groups, see EP-A-0 495 375.
• the description of non-coordinating anions and precursors thereto of these documents are similarly incorporated by reference for purposes of U.S. Patent Practice.
• Suitable activators capable of ionic cationization of the metallocene compounds of the invention, and consequent stabilization with a resulting non-coordinating anion include: trialkyl-substituted ammonium salts such as; triethylammonium tetraphenylborate, tripropylammonium tetraphenylborate, tri(n-butyl)ammonium tetraphenylborate, trimethylammonium tetrakis(p-tolyl)borate, trimethylammonium tetrakis(o-tolyl)borate, tributyl ammonium tetrakis(pentafluorophenyl)borate, tripropylammonium tetrakis(o,p-dimethylphenyl)borate, tributylammonium tetrakis(m,m-dimethylphenyl)borate, tributylammonium tetrakis
• N,N-dialkyl anilinium salts such as;
• triaryl phosphonium salts such as; triphenylphosphonium tetraphenylborate, tri(methylphenyl)phosphonium tetraphenylborate, tri(dimethylphenyl)phosphonium tetraphenylborate and the like.
• suitable anionic precursors include those comprising a stable carbonium ion, and a compatible non-coordinating anion. These include; tropyllium tetrakis(pentafluorophenyl)borate, triphenylmethylium tetrakis(pentafluorophenyl)borate, benzene (diazonium) tetrakis(pentafluorophenyl)borate, tropillium phenyltris(pentafluorophenyl)borate, triphenylmethylium phenyl-(trispentafluorophenyl)borate, benzene (diazonium) phenyl-tris(pentafluorophenyl)borate, tropillium tetrakis(2,3,5,6-tetrafluorophenyl)borate, triphenylmethylium tetrakis(2,3, 5, 6-tetrafluorophenyl)borate,
• a particularly preferred catalyst system if ⁇ -(CH 3 ) 2 Si(indenyl) 2 Hf(CH 3 ) 2 with a cocatalyst of N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate.
• EP copolymers of this invention have unique properties as evidenced by the relationship of their isotactic index and propylene triad tacticity to their ethylene content. Isotactic index and triad tacticity were determined for this invention's EP copolymers in the manner described below.
• Copolymers of this invention can be blended with processing oil and other common additives such as nucleating agents, antioxidants, fillers, etc. and fabricated into objects used in a variety of applications mentioned above. Also, blends comprising the copolymers of this invention and other alpha- olefin polymers and copolymers, e.g., polypropylene, are fabricated into objects used in a variety of applications mentioned above. Generally, these blends contain processing oil and other common additives such as nucleating agents, antioxidants, fillers, etc.
• Copolymers of the invention preferably have a polydispersity index (M w /M n ) of from 1.5 to 10, more preferably from 1.8 to 8, even more preferably from 2.0 to 5.
• Polypropylene isotactic index is determined by infra-red (LR) spectroscopy.
• the IR spectra of polypropylene yields two observable peaks at 997 cm “1 and 973 cm “1 .
• the quotient of absorbance at 997 cm “1 divided by the absorbance at 973 cm “1 is a recognized measure of isotacticity.
• Polypropylene isotactic index is defined as this quotient multiplied by 100.
• the EP copolymers made by this invention have unique crystalline characteristic as measured by isotactic index.
• Figure 1 is a graph depicting the relationship of isotactic index of a given copolymer to its mole % ethylene content.
• the data from this invention's copolymers and EPA 037659 are plotted on the graph.
• the copolymers of this invention have a lower isotactic index for any given ethylene content when compared to EPA 037659.
• the lower isotactic index corresponds to relatively lower crystallinity that translates into better elastomeric properties such as high tensile strength and elongation at break coupled with very good elastic recovery. Good elastomeric properties are important for some of the potential applications mentioned above.
• Triad Tacticity refers to the stereogenicity in a polymer.
• the chirality of adjacent monomers can be of either like or opposite configuration.
• the term “diad” is used to designate two contiguous monomers; three adjacent monomers are called a triad. If the chirality of adjacent monomers is of the same relative configuration, the diad is called isotactic; if opposite in configuration, it is termed syndiotactic.
• Another way to describe the configurational relationship is to term contiguous pairs of monomers having the same chirality as meso (m) and those of opposite configuration racemic (r).
• the stereoregularity of the triad is 'mm'. If two adjacent monomers in a three-monomer sequence have the same chirality and that is different from the relative configuration of the third unit, this triad has 'mr' tacticity. An 'rr' triad has the middle monomer unit having an opposite configuration from either neighbor. The fraction of each type of triad in the polymer can be determined and when multiplied by 100 indicates the percentage of that type found in the polymer.
• the triad tacticity can be determined from a C-NMR spectrum of the propylene copolymer.
• the C-NMR spectrum is measured in the following manner. To measure the C-NMR spectrum, 250-350 mg of polymer is completely dissolved in deuterated tetrachloroethane in a NMR sample tube (diameter: 10 mm) at 120° C. The measurement is conducted with full proton decoupling using a 90° pulse angle and at least a 15 second delay between pulses With respect to measuring the chemical shifts of the resonances, the methyl group of the third unit in a sequence of 5 contiguous propylene units consisting of head-to-tail bonds and having the same relative chirality is set to 21.83 ppm.
• the chemical shift of other carbon resonances are determined by using the above- mentioned value as a reference.
• the spectrum relating to the methyl carbon region (17.0-23 ppm) can be classified into the first region (21.1-21.9 ppm), the second region (20.4-21.0 ppm), the third region (19.5-20.4 ppm) and the fourth region (17.0-17.5 ppm).
• Each peak in the spectrum was assigned based on the work described in Polymer, Vol. 30 (1989) p. 1350, or Macromolecules, Vol. 17 (1984) p. 1950.
• the signal of the center methyl group in a PPP (mm) triad is located.
• the signal of the center methyl group in a PPP (mr) triad and the methyl group of a propylene unit whose adjacent units are a propylene unit and an ethylene unit resonates (PPE-methyl group).
• the signal of the center methyl group in a PPP (rr) triad and the methyl group of a propylene unit whose adjacent units are ethylene units resonate (EPE-methyl group).
• PPP (mm), PPP (mr) and PPP (rr) have the following three-propylene units- chain structure with head-to-tail bonds, respectively.
• the triad tacticity (mm fraction) of the propylene copolymer can be determined from a 13 C-NMR spectrum of the propylene copolymer and the following formula:
• the peak areas used in the above calculation are not measured directly from the triad regions in the CNMR spectrum.
• the intensities of the mr and rr triad regions need to have subtracted from them the areas due to EPP and EPE sequencing, respectively.
• the EPP area can be determined from the signal at 30.8 ppm after subtracting from it one half the area of the sum of the signals between 26 and 27.2 ppm and the signal at 30.1 ppm.
• the area due to EPE can be determined from the signal at 33.2 ppm.
• the area of the mr region may be adjusted by subtracting one half of the area between 34 and 36 ppm and the area of the rr region may be adjusted by subtracting the intensity found between 33.7 and 40.0 ppm. Therefore, by making the above adjustments to the mr and rr regions the signal intensities of the mm, mr and rr triads can be determined and the above formula applied.
• the EP copolymers made by this invention have unique propylene tacticity as measured by % meso triad.
• Figure 2 is a graph depicting the relationship of % meso triad of a given copolymer to its mole % ethylene content. The data from this invention's copolymers and U.S. Pat. No. 5,504,172 are plotted on the graph. As shown by figure 2, the copolymers of this invention have a lower % meso triad for any given ethylene content when compared to U.S. Pat. No. 5,504,172.
• % meso triads corresponds to relatively lower crystallinity that translates into better elastomeric properties such as high tensile strength and elongation at break coupled with very good elastic recovery. Good elastomeric properties are important for some of the potential applications mentioned on page 1.
• Tg Glass transition temperature of polymer is usually measured by differential scanning calorimetry (DSC).
• DSC differential scanning calorimetry
• MDSC modulated DSC
• DSC conventional DSC technique
• the copolymer of the invention preferably has a reactivity ratio product (rlxr2) equal to or less than 2.5.
• DSC has a standard protocol of loading a calorimeter at 20 °C with a specimen free of molding strains, cooling the sample to - 75 °C, scanning to 180 °C at 10 °C/min., cooling to -75 °C, and re-running the scan.
• Tg and melting point (T M ) are evaluated.
• Thermal analyzer instruments' model 2910 is used. 5- 10 mg of polymer sample is loaded in the instrument at ambient temperature.
• the general analysis procedure calls for subjecting the sample to the following thermal segments in the order given below:
• GPC Gel permeation chromatography
• the distribution of pore sizes thus determines the size range over which separation occurs, as well as the extent of separation, with large molecules eluting before smaller ones.
• a Differential Refractive Index (DRI) detector is used to measure polymer concentration as a function of elution time (or elution volume).
• DRI Differential Refractive Index
• a pre-established calibration curve based on polystyrene standards, allows this raw data to be converted into concentration vs molecular weight data.
• the number, weight, and z-average molecular weights (M n , M w , and M j , respectively) are then calculated from these results.
• COLUMNS 3 Shodex AT-806MS (mixed bed) MOBILE PHASE: filtered TCB, 300 ppm antioxidant (Santonox) TEMPERATURE: 145 °C (column and injector compartments) RUN TIME: 50 minutes INJECTION VOLUME: 300 ⁇ L
• 4-6 mg of polymer is weighted into a 4 mL WISP vial, sufficient TCB is added to yield a concentration of 1.5 mg/mL, and the vial is capped with a PTFE septum and labeled with the work request number.
• TCB from a single source is used for both sample preparation and the mobile phase to minimize instability in the DRI signal as the lowest molecular weight components elute (i.e.,
• solvent mis-match peaks).
• the sample is placed in the shaker oven at 160-170 °C for 3-4 hours while continuously agitating at a rate of 120-160 rpm.
• the vials are transferred to a pre-heated sample carousel, and the carousel quickly placed into the heated injector compartment of the GPC.
• the set of samples are run according to the directions for normal operation in the waters 150-C GPC manual.
• FIG. 3 is a graph depicting the relationship of T g of a given copolymer to its mole % ethylene content. The data from this invention's copolymers are plotted on the graph.
• the polymers of Examples 1-3 were made with the following general procedure. Polymerizations were carried in a one liter stirred reactor with continuous flow of feeds to the system and continuous withdrawal of products. Solvent, including hexane, and monomers including ethylene and propylene were purified over beds of alumina and 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 which flowed as a gas under its own pressure through a mass flow meter/controller. Reactor temperature was controlled by circulating water through a reactor cooling jacket. The reactor was maintained at a pressure in excess of the vapor pressure of the reactant mixture to keep the reactants in the liquid phase. The reactor was operated liquid full.
• Ethylene and propylene feeds were combined into one stream and then mixed with a pre-chilled hexane stream that had been cooled to at least 0 °C.
• a hexane solution of triisobutyl 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 catalyst solution was prepared by dissolving ⁇ -Me 2 Si(indenyl) 2 HfMe 2 catalyst and (N,N dimethylaniliniumtretakis
• Examples 4-6 were made with the following general procedure.
• a 5 gallon autoclave stirred tank reactor equipped with an external jacket for temperature control, was charged with 29 pounds of dry toluene (diluent). Hexane or other inert hydrocarbon solvent may be used in place of toluene.
• 40 grams of 25% solution of triisobutyl aluminum scavenger was charged to the reactor. The contents of the reactor were stirred and maintained at a certain initial temperature shown in table 2.
• ethylene (C 2 ) and propylene (C 3 ) feed lines were tied together to obtain a premixed monomer feed that is fed into the reactor via a single dip tube.
• ethylene and propylene may be fed directly to the reactor through individual entry tubes.
• the flow rates of ethylene and propylene were adjusted to give desired C 3 / C 2 monomer ratio.
• a catalyst solution containing 121 mg of ⁇ -Me 2 Si(Indenyl) 2 HfMe 2 and 151 mg of N,N- Dimethylanilinium tetrakis(pentafluorophenyl)boron in 100 ml of dry toluene, was charged in a catalyst bomb.
• This bomb was a part of a catalyst delivery setup capable of delivering 15 ml of catalyst solution per addition to the reactor.
• 30 - 45 ml of catalyst solution was added to the reactor to induce polymerization. Additional catalyst solution is added at desired time intervals during the polymerization.
• Reactor pressure, temperature and C 3 & C 2 flow rates were monitored throughout the polymerization run that typically lasts for 10 - 30 minutes.
• the reactor effluent was transferred, under nitrogen pressure, to a devolitizing unit.
• a continuous flow of steam was introduced in this unit for a long period of time to insure evaporation of diluent.
• Vacuum was usually applied to accelerate devolitization of diluent.
• the moler ratio of C 3 :C 2 in this mixture was 3.5: 1.
• the flow of monomer mixture continued from the feed vessel to reactor until there is no pressure difference between the two. At this time the reactor inlet valve was shut off and polymerization was continued. Reactor pressure and temperature was monitored throughout the polymerization. A temperature jump was observed of 18° C (-10° C to 8° C) over a period of 5 minutes since the introduction of the monomer mixture in the reactor. After the initial jump, the reactor temperature leveled off and decreased with increasing polymerization time. Reactor pressure decreased gradually during the polymerization. The reactor was vented completely after 20 minutes of polymerization and the contents of the reactor were poured into a beaker containing large excess of acetone. The precipitated polymer was dried under vacuum at 100 °C for 24 hours. The polymer yield was 20 gm.
• % RECOVERY Microtensile specimens were pulled at 5 inch/min. Rate in an Instron and held for 10 minutes at 150% elongation and then released.
• Residual set was measured after 10 minutes.
• Recovery a measure of elasticity
• fabricated products comprising the claimed copolymer of this invention are also part of this invention.
• Such fabricated products can also optionally comprise one or more of an alpha olefin polymer or copolymer, a processing oil, and other additives.
• an alpha olefin polymer is polypropylene.

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• 1999
  • 1999-07-01 WO PCT/US1999/014967 patent/WO2000001745A1/en not_active Application Discontinuation
  • 1999-07-01 AU AU49652/99A patent/AU4965299A/en not_active Abandoned
  • 1999-07-01 JP JP2000558143A patent/JP5144860B2/ja not_active Expired - Lifetime
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