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
  • C08F210/16—Copolymers of ethene with alpha-alkenes, e.g. EP rubbers
  • C08F210/18—Copolymers of ethene with alpha-alkenes, e.g. EP rubbers with non-conjugated dienes, e.g. EPT 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
  • C08F10/00—Homopolymers and copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond
• • 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
  • C08F4/65912—Component covered by group C08F4/64 containing a transition metal-carbon bond in combination with an organoaluminium compound

Definitions

• This invention relates to a class of Group 4 metal complexes and to olefin polymerization catalysts derived therefrom that are particularly suitable for use in a polymerization process for preparing polymers by polymerization of ⁇ -olefins and mixtures of ⁇ - olefins, and to the ⁇ -olefins and mixtures of ⁇ -olefins resulting therefrom.
• Constrained geometry metal complexes and methods for their preparation are disclosed in EP-A-416,815; EP-A-468,651; EP-A-514,828; EP-A-520,732 and WO93/19104, as well as US-A-5,055,438, US-A-5,057,475, US-A-5,096,867, US-A-5,064,802, US-A-5, 132,380, US-A- 5,470,993, WO95/00526, and US Provisional Application 60-005913.
• Variously substituted indenyl containing metal complexes have been taught in U.S. Serial No. 592,756, filed January 26, 1996, as well as WO 95/14024.
• Constrained geometry catalysts and other single site or metallocene catalysts are useful to prepare homogeneous olefin polymers.
• the term "homogeneous olefin polymers" refers to homopolymers or interpolymers of one or more ⁇ -olefins which are characterized as having a narrow polydispersity, that is, an MJM n of from 1.5 to 3.0, and, in the case of interpolymers, a homogeneous short chain branching distribution, that is, wherein each molecule has substantially the same number of short chain branches.
• Homogeneous olefin polymers are advantageous over Ziegler Natta produced polymers, in that they lack a low molecular weight tail fraction, which translates to improved strength and toughness.
• Homogeneous olefin polymers are further advantageous over Ziegler Natta produced polymers, in that the catalysts useful to prepare such polymers, particularly the constrained geometry catalysts, readily and efficiently incorporate comonomer, which permits the cost-effective production of polymers having a density of less than 0.910 g/cm 3 which accords good elastomeric properties.
• homogeneous polymers are typically more difficult to process than their Ziegler Natta counterparts, in part due to the absence of the low molecular weight fraction and in part due to the narrowness of the melting region.
• One preferred class of homogeneous olefin polymers is the class of substantially linear polymers, which are characterized as having a narrow polydispersity, a homogeneous short chain branching distribution, and the presence of sufficient long chain branching to provide improved rheological properties and resistance to melt fracture.
• substantially linear polymers are disclosed and claimed in U.S. Patent Nos. 5,272,236; 5,278,272; 5,380,810; and EP 659,773; EP 676,421 ; and WO 94/07930.
• An alternate approach to utilizing the preferred substantially linear olefin polymers has been to incorporate into homogeneous olefin polymers effective amounts of polymer processing aids prior to fabrication into films or articles.
• 5,621 ,126 asserts that catalysts containing an amido group having a hydrocarbyl ligand R' which is aliphatic or alicyclic and which is bonded to the nitrogen atom through a primary or secondary carbon produce copolymers having a greater degree of ⁇ -olefin incorporation than catalysts wherein the hydrocarbyl ligand R' is bonded to the nitrogen atom through a tertiary carbon atom or wherein R' bears aromatic carbon atoms.
• 5,621 ,126 asserts that when the R' ligand is bonded to the nitrogen atom through a secondary carbon atom, the activity of the catalyst is greater when R' is alicyclic than when R' is bonded to the nitrogen through a primary carbon atom of an aliphatic group of identical carbon number.
• U.S. Patent No. 5,621 ,126 asserts that as the number of carbon atoms of R' thereof increases, the productivity of the catalyst system and the molecular weight of the ethylene/ ⁇ -olefin copolymer increase while the amount of ⁇ -olefin comonomer incorporated remains about the same or increases.
• U.S. Patent No. 5,621 ,126 asserts that the more preferred R' ligand is cyclododecyl.
• compositions of U.S. 5,621 ,126 are disadvantageous, in that they are believed to lack long chain branching, making them susceptible to melt fracture, and thus, less commercially desirable.
• mono(cyclopentadienyl) Group IV B metal compounds may indeed find great commercial advantage in the polymerization of ethylene/ ⁇ -olefin interpolymers, those in industry are continually seeking improvements and, in particular, would find advantage in catalysts which withstand higher reaction temperatures than are characteristic of mono(cyclopentadienyl) catalysts. Such higher reaction temperatures would translate to polymers exhibiting a high degree of vinyl unsaturation, making them especially useful as precursors to functionalized polymers, and enhancing long chain branch incorporation when appropriate polymerization conditions are employed.
• a product produced by a process for preparing polymers of olefin monomers comprising contacting one or more such monomers with a catalyst comprising:
• M is titanium, zirconium or hafnium in the +2, +3 or +4 formal oxidation state
• A' is a substituted indenyl group substituted in at least the 2 or 3 position with a group selected from hydrocarbyl, fluoro-substituted hydrocarbyl, hydrocarbyloxy-substituted hydrocarbyl, dialkylamino- substituted hydrocarbyl, silyl, germyl and mixtures thereof, said group containing up to 40 nonhydrogen atoms, and said A' further being covalently bonded to M by means of a divalent Z group;
• Z is a divalent moiety bound to both A' and M via ⁇ -bonds, said Z comprising boron, or a member of Group 14 of the Periodic Table of the Elements, and also comprising nitrogen, phosphorus, sulfur or oxygen, wherein Z preferably has covalently bonded thereto an aliphatic or cycloaliphatic hydrocarbyl or substituted hydrocarbyl group, such that the hydrocarbyl group is covalently bonded to Z via a primary or secondary carbon;
• X is an anionic or dianionic ligand group having up to 60 atoms exclusive of the class of ligands that are cyclic, delocalized, ⁇ -bound ligand groups; X' independently each occurrence is a neutral ligating compound, having up to 20 atoms; p is 0, 1 or 2, and is two less than the formal oxidation state of M, with the proviso that when X is a dianionic ligand group, p is 1; and q is 0, 1 or 2; and
• an activating cocatalyst the molar ratio of 1) to 2) being from 1:10,000 to 100:1 , or the reaction product formed by converting 1) to an active catalyst by use of an activating technique.
• M is titanium, zirconium or hafnium in the +2, +3 or +4 formal oxidation state
• R' and R" are independently each occurrence hydride, hydrocarbyl, silyl, germyl, halide, hydrocarbyloxy, hydrocarbylsiloxy, hydrocarbylsilylamino, di(hydrocarbyl)amino, hydrocarbyleneamino, di(hydrocarbyl)phos ⁇ hino, hydrocarbylene-phosphino, hydrocarbylsulfido, halo-substituted hydrocarbyl, hydrocarbyloxy-substituted hydrocarbyl, silyl- substituted hydrocarbyl, hydrocarbylsiloxy-substituted hydrocarbyl, hydrocarbylsilylamino- substituted hydrocarbyl, di(hydrocarbyl)amino-substituted hydrocarbyl, hydrocarbyleneamino- substituted hydrocarbyl, di(hydrocarbyl)phosphino-substituted hydrocarbyl, hydrocarbylene- phos
• R'" is a divalent hydrocarbylene- or substituted hydrocarbylene group forming a fused system with the remainder of the metal complex, said R'" containing from 1 to 30 nonhydrogen atoms;
• Z is a divalent moiety, or a moiety comprising one ⁇ -bond and a neutral two electron pair able to form a coordinate-covalent bond to M, said Z comprising boron, or a member of Group 14 of the Periodic Table of the Elements, and also comprising nitrogen, phosphorus, sulfur or oxygen;
• X is a monovalent anionic ligand group having up to 60 atoms exclusive of the class of ligands that are cyclic, delocalized, ⁇ -bound ligand groups;
• X' independently each occurrence is a neutral ligating compound having up to 20 atoms
• X" is a divalent anionic ligand group having up to 60 atoms
• p is zero, 1 , 2, or 3;
• q is zero, 1 or 2
• r is zero or 1 ;
• an activating cocatalyst the molar ratio of 1) to 2) being from 1 :10,000 to 100:1 , or the reaction product formed by converting 1 ) to an active catalyst by use of an activating technique.
• the present catalysts and process employed in the polymerization of the polymers of the invention result in the highly efficient production of high molecular weight olefin polymers, particularly ethylene/ ⁇ -olefin interpolymers, ethylene/propylene/diene interpolymers (EPDM), wherein the diene is ethylidenenorbornene, 1 ,4-hexadiene, or a similar nonconjugated diene, or is piperylene, over a wide range of polymerization conditions, and especially at elevated temperatures.
• ethylene/ ⁇ -olefin interpolymers particularly ethylene/ ⁇ -olefin interpolymers, ethylene/propylene/diene interpolymers (EPDM), wherein the diene is ethylidenenorbornene, 1 ,4-hexadiene, or a similar nonconjugated diene, or is piperylene
• the subject invention further provides an olefin interpolymer, preferably an interpolymer of ethylene and at least one C 3 -C 20 ⁇ -olefin, characterized as satisfying at least four of the following criteria, especially all five of the following criteria: a) an l 2 ⁇ 100 g/10 min, b) an MJM n of from 1.5 to 3.0, c) at least 0.03 vinyls/1000 carbons, as determined by FTIR, and d) at least two distinct ATREF peaks, each of which satisfies the following inequality: ATREF Shape Factor ⁇ 0.90 - 0.00626 (Average Elution Temperature) .
• the use of the indenyl and indecenyl catalysts as disclosed herein leads to the production of polymers having a high degree of vinyl termination.
• the resultant high level of vinyls/1000 carbons makes the polymers of the invention especially useful in applications wherein the polymers are subsequently functionalized.
• the resultant high level of vinyls/1000 carbons further makes the polymers able to achieve higher levels of long chain branching when appropriate polymerization conditions are employed.
• the polymers of the invention will be characterized as having an I ]0 /I 2 of at least 10, preferably at least 12, and most preferably at least 15.
• the polymers of the invention will preferably further be characterized as exhibiting a critical shear rate at the onset of surface melt fracture which is at least 50 percent greater than the critical shear rate at the onset of surface melt fracture for a linear interpolymer, wherein the substantially linear interpolymer and the linear interpolymer comprise the same comonomer or comonomers, the linear interpolymer has an l 2 , MJM n and density within ten percent of that of the substantially linear interpolymer, and wherein the respective critical shear rates of the substantially linear interpolymer and the linear interpolymer are measured at the same melt temperature using a gas extrusion r eometer.
• the olefin interpolymers of the invention are uniquely characterized as being bimodal with respect to the short chain branching distribution and molecular weight, as evidenced by the differential scanning calorimetry and ATREF curves, as well as the deconvoluted gel permeation chromatographs. This effect is particularly true for interpolymers having a density of no more than 0.910 g/cm 3 .
• interpolymers of the invention having a density less than 0.890 g/cm 3 , particularly having a density of no more than 0.880 g/cm 3 , and more particularly having a density of less than 0.870 g/cm 3 have a particularly superior and highly unique balance of properties.
• such polymers have improved elastomeric properties, such as a compression set of less than 90 percent, preferably less than 85 percent, more preferably less than 80 percent, coupled with an upper service temperature which exceeds that of a physical blend of interpolymers corresponding to the components of the interpolymers of the invention as discerned by the deconvolution of the representative gel permeation chromatograph.
• the uniqueness of the interpolymers of the invention is evident in micrographs obtained by transmission electron microscropy, which clearly show the presence of lamella in interpolymers whose density would suggest should be wholly amorphous.
• olefin interpolymers of the invention are expected to have great utility in a variety of applications, including but not limited to films, fibers, foams, injection molded parts, rotational molded parts, and as components of formulations such as adhesives, sealants, coatings, caulks, and asphalt.
• FIGURE 1 is an illustration of catalysts, cocatalysts, and scavenging compounds practiced in the examples set forth herein.
• FIGURE 2 is a DSC endogram of an ethylene/octene interpolymer of Comparative Example C-3a prepared using Catalyst Three.
• FIGURE 3 is a DSC endogram of the ethylene/octene interpolymer of Example 1a prepared using Catalyst One.
• FIGURE 4 is a DSC endogram of the ethylene/octene interpolymer of Example 2a prepared using Catalyst Two.
• FIGURE 5 is a transmission electron micrograph of the ethylene/octene interpolymer of Example 2a prepared using Catalyst Two.
• FIGURE 6 is a transmission electron micrograph of the ethylene/octene interpolymer of Comparative Example C-3a prepared using Catalyst Three.
• FIGURE 7a are ATREF curves of two ethylene/octene interpolymers of the invention, prepared with Catalyst One (Example 1 b) and Catalyst Two (Example 2a), respectively, and of the ethylene/octene interpolymer of Comparative Example C-3a prepared with Catalyst Three.
• FIGURE 7b are ATREF curves of an ethylene/octene interpolymer prepared with Catalyst Two, and of a comparative ethylene/octene interpolymer having a density of 0.895 g/cm 3 and a melt index (l 2 ) of 1.6 g/10 minutes prepared with Catalyst Three.
• FIGURE 7c are ATREF and differential viscosity curves of the ethylene/octene interpolymer of Example 45(e) prepared with Catalyst Two.
• FIGURE 7d is a plot of the ATREF shape factor versus the average ATREF elution temperature.
• FIGURE 8a and 8b provide dynamic mechanical data for ethylene/octene interpolymers prepared with Catalyst One (Example 1a) and Catalyst Two (Example 2a), respectively, and for a ethylene/octene interpolymer of prepared with Catalyst Three (Comparative Example C-3a).
• FIGURE 9a is a plot of the upper service temperature (UST) of ethylene/octene interpolymers prepared with Catalyst Two and of comparative ethylene/octene interpolymers prepared with Catalyst Three, and of a blend of two ethylene/octene interpolymers prepared with Catalyst Three.
• UST upper service temperature
• FIGURE 9b is a plot of the difference between the UST of various blends of ethylene/octene interpolymers prepared using Catalyst Three with the UST of interpolymers of the invention set forth in FIGURE 9a.
• FIGURE 10 is a deconvoluted gel permeation chromatogram of the ethylene/octene interpolymer of Example 1b prepared with Catalyst One.
• FIGURE 11 is a deconvoluted gel permeation chromatogram of the ethylene/octene interpolymer of Example 2b prepared with Catalyst Two.
• FIGURE 12 is a deconvoluted gel permeation chromatogram of the ethylene/octene interpolymer of Comparative Example C-2a prepared with Catalyst Two and using a batch polymerization process.
• FIGURE 13 are viscosity curves for the ethylene/octene interpolymers of Example 2a prepared using Catalyst Two in a continuous solution polymerization process and of Comparative Example C-2a prepared using Catalyst Three in a solution batch polymerization process.
• FIGURE 14 is a depiction of the compression set of ethylene/octene interpolymers prepared using Catalysts One and Two, respectively, and of an ethylene/octene interpolymer prepared using Catalyst Three.
• FIGURES 15 and 16 are DSC curves for an EPDM of the invention.
• Density is measured in accordance with ASTM D-792. The samples are annealed at ambient conditions for 24 hours before the measurement is taken. Melt index (I2), is measured in accordance with ASTM D-1238, condition 190°C/2.16 kg
• Waters 150°C high temperature chromatographic unit equipped with three mixed porosity columns (Polymer Laboratories 103, 104, 105, and 106), operating at a system temperature of 140°C.
• the solvent is 1 ,2,4-trichlorobenzene, from which 0.3 percent by weight solutions of the samples are prepared for injection.
• the flow rate is 1.0 mL/min. and the injection size is 100 microliters.
• the molecular weight determination is deduced by using narrow molecular weight distribution polystyrene standards (from Polymer Laboratories) in conjunction with their elution volumes.
• the equivalent polyethylene molecular weights are determined by using appropriate Mark-Houwink coefficients for polyethylene and polystyrene (as described by Williams and Word in Journal of Polymer Science, Polymer Letters, Vol. 6, (621) 1968, incorporated herein by reference) to derive the following equation:
• M w ⁇ Wj * Mj, where Wj and M j are the weight fraction and molecular weight, respectively, of the ith fraction eiuting from the
• %C (A/292 J/g) x 100, in which %C represents the percent crystallinity and A represents the heat of fusion of the ethylene in Joules per gram (J/g) as determined by differential scanning calorimetry (DSC).
• DSC Differential scanning calorimetry
• the morphology of the copolymers were investigated by transmission electron microscopy (TEM). Samples were stained with ruthenium chloride-hypochlorite and then thin slices were prepared with a glass knife on a microtome at room temperature. Micrographs were recorded at 150000-fold magnification on a JEOL 2000FX microscope. Analytical temperature rising elution fractionation (ATREF) data were generated using the standard equipment within Polyolefins Research. The polymer sample (dissolved in hot trichlorobenzene) was crystallized in a column containing an inert support (steel shot) by slowly reducing the temperature.
• TEM transmission electron microscopy
• An ATREF chromatogram was then generated by eiuting the crystallized sample from the column by slowly increasing the temperature of the eiuting solvent, trichlorobenzene.
• the ATREF curve illustrated several key structural features of the resin. For example, the response from the refractive index detector gives the short chain branching distribution; while the response from the differential viscometer detector provides an estimate of the viscosity average molecular weight.
• Dynamic mechanical spectroscopy measurements were made on the RMS-800 dynamic mechanical spectrometer using 25 mm diameter parallel plates (gap 2mm) in the oscillatory shear mode. Frequency sweeps were performed over the shear rate ranges of 0.1 to 100 rad/s at 15 percent strain in a nitrogen atmosphere at 190°C. Temperature sweeps were also performed on the RDAII dynamic analyzer. In this case 12.5 mm diameter parallel plates (gap 1.5mm) were used over the temperature range from about -100°C to 200°C at a frequency of 1 rad/s in a nitrogen atmosphere. The sample was loaded at room temperature, heated to 60°C to ensure good contact between the sample and the plates and then cooled to -100°C prior to beginning the temperature sweep experiment.
• Olefins as used herein are C 2 . 20 aliphatic or aromatic compounds containing vinylic unsaturation, as well as cyclic compounds such as cyclobutene, cyclopentene, and norbornene, including norbornene substituted in the 5 and 6 position with C ⁇ o hydrocarbyl groups. Also included are mixtures of such olefins as well as mixtures of such olefins with C 4 ⁇ , 0 diolefin compounds. Examples of the latter compounds include ethylidene norbornene, 1 ,4-hexadiene, norbornadiene, and the like.
• the catalysts and process herein are especially suited for use in preparation of ethylene/propylene, ethylene/1-butene, ethylene/1 -pentene, ethylene/4-methyl-1- pentene, ethylene/1-hexene, ethylene/1-octene, and ethylene/styrene interpolymers as well as terpolymers of ethylene, propylene and a nonconjugated diene, that is EPDM terpolymers, with interpolymers of ethylene and a C 3 -C 20 ⁇ -olefin, preferably at C 4 -C 20 ⁇ -olefin, and more preferably a C 6 -C 10 ⁇ -olefin, with ethylene/1-octene polymers being especially preferred.
• interpolymers of the invention will preferably be prepared using catalyst systems derived from a metal complex corresponding to the formula:
• M is titanium, zirconium or hafnium in the +2, +3 or +4 formal oxidation state
• A' is a substituted indenyl group substituted in at least the 2 or 3 position with a group selected from hydrocarbyl, fluoro-substituted hydrocarbyl, hydrocarbyloxy-substituted hydrocarbyl, dialkylamino- substituted hydrocarbyl, silyl, germyl and mixtures thereof, said group containing up to 40 nonhydrogen atoms, and said A' further being covalently bonded to M by means of a divalent Z group;
• Z is a divalent moiety bound to both A' and M via ⁇ -bonds, said Z comprising boron, or a member of Group 14 of the Periodic Table of the Elements, and also comprising nitrogen or phosphorus, wherein an aliphatic or alicyclic hydrocarbyl group is covalently bonded to the nitrogen or phosphorus via a primary or secondary carbon;
• X is an anionic or dianionic ligand group having up to 60 atoms exclusive of the class of ligands that are cyclic, delocalized, ⁇ -bound ligand groups;
• X' independently each occurrence is a neutral ligating compound, having up to 20 atoms; p is 0, 1 or 2, and is two less than the formal oxidation state of M, with the proviso that when X is a dianionic ligand group, p is 1; and q is 0, 1 or 2.
• Preferred X' groups are carbon monoxide; phosphines, especially trimethylphosphine, triethylphosphine, triphenylphosphine and bis(1 ,2-dimethylphosphino)ethane; P(OR) 3 , wherein R is as previously defined; ethers, especially tetrahydrofuran; amines, especially pyridine, bipyridine, tetramethylethylenediamine (TMEDA), and triethylamine; olefins; and conjugated dienes having from 4 to 40 carbon atoms.
• Complexes including the latter X' groups include those wherein the metal is in the +2 formal oxidation state.
• M is preferably zirconium or titanium, and is more preferably titanium.
• Preferred substituted indenyl coordination complexes used according to the present invention are complexes corresponding to the formula:
• R and R 2 independently are groups selected from hydrogen, hydrocarbyl, perfluoro substituted hydrocarbyl, silyl, germyl and mixtures thereof, said group containing up to 20 nonhydrogen atoms, with the proviso that at least one of R, or R 2 is not hydrogen;
• R 3 , R 4 , R 5 , and R 6 independently are groups selected from hydrogen, hydrocarbyl, perfluoro substituted hydrocarbyl, silyl, germyl and mixtures thereof, said group containing up to 20 nonhydrogen atoms;
• M is titanium, zirconium or hafnium
• Z is a divalent moiety comprising boron, or a member of Group 14 of the Periodic Table of the Elements, and also comprising nitrogen or phosphorus, said moiety having up to 60 non- hydrogen atoms, wherein an aliphatic or alicyclic hydrocarbyl group is covalently bonded to the nitrogen or phosphorus via a primary or secondary carbon; p is O, 1 or 2; q is zero or one; with the proviso that: when p is 2, q is zero, M is in the +4 formal oxidation state, and X is an anionic ligand selected from the group consisting of halide, hydrocarbyl, hydrocarbyloxy, di(hydrocarbyl)amido, di(hydrocarbyl)phosphido, hydrocarbylsulfido, and silyl groups, as well as halo-, di(hydrocarbyl)amino-, hydrocarbyloxy- and di(hydrocarbyl)phosphino-
• R 1 and R 2 are hydrogen or C ⁇ alkyl, with the proviso that at least one of R-, or R 2 is not hydrogen;
• R 3 , R 4 , R 5 , and R 6 independently are hydrogen or C, ⁇ alkyl
• M is titanium
• Y is -NR ** -, -PR ** -;
• R* each occurrence is independently hydrogen, or a member selected from hydrocarbyl, hydrocarbyloxy, silyl, halogenated alkyl, halogenated aryl, and combinations thereof, said R* having up to 20 non-hydrogen atoms, and optionally, two R * groups from Z (when R* is not hydrogen), or an R* group from Z and an R* group from Y form a ring system;
• R** is a aliphatic or alicyclic hydrocarbyl group covalently bonded to the nitrogen or phosphorus of Y via a primary or secondary carbon; p is O, 1 or 2; q is zero or one; with the proviso that: when p is 2, q is zero, M is in the +4 formal oxidation state, and X is independently at each occurrence methyl or benzyl, when p is 1 , q is zero, M is in the +3 formal oxidation state, and X is 2-(N,N- dimethyl)aminobenzyl; or M is in the +4 formal oxidation state and X is 1 ,4-butadienyl, and when p is 0, q is 1 , M is in the +2 formal oxidation state, and X' is 1,4-diphenyl-1 ,3- butadiene or 1,3-pentadiene.
• the latter diene is illustrative of unsymmetrical diene groups that result
• Preferred substituted indenecyl metal complexes correspond to the following formula :
• R' is hydrocarbyl, di(hydrocarbylamino), or a hydrocarbyleneamino group, said R' having up to 20 carbon atoms, R" is C ⁇ _2 ⁇ , hydrocarbyl or hydrogen;
• M is titanium
• Y is -0-, -S-, -NR * -, -PR * -; -NR 2 * , or -PR 2 * ;
• R* each occurrence is independently hydrogen, or a member selected from hydrocarbyl, hydrocarbyloxy, silyl, halogenated alkyl, halogenated aryl, and combinations thereof, said R* having up to 20 non-hydrogen atoms, and optionally, two R* groups from Z (when R* is not hydrogen), or an R* group from Z and an R* group from Y form a ring system;
• X, X' and X" are as previously defined; p is O, 1 or 2; q is zero or 1 ; and r is zero or 1 ; with the proviso that: when p is 2, q and r are zero, M is in the +4 formal oxidation state (or M is in the +3 formal oxidation state if Y is -NR * 2 or -PR * 2 ), and X is an anionic ligand selected from the group consisting of halide, hydrocarbyl, hydrocarbyloxy, di(hydrocarbyl)amido, di(hydrocarbyl)phosphido, hydrocarbylsulfido, and silyl groups, as well as halo-, di(hydrocarbyl)amino-, hydrocarbyloxy-, and di(hydrocarbyl)phosphino-substituted derivatives thereof, said X group having up to 30 nonhydrogen atoms,
• X is a dianionic ligand selected from the group consisting of hydrocarbadiyl, oxyhydrocarbyl, and hydrocarbylenedioxy groups, said X group having up to 30 nonhydrogen atoms,
• X is a stabilizing anionic ligand group selected from the group consisting of allyl, 2-(N,N-dimethylamino)phenyl, 2-(N,N-dimethylaminomethyl)phenyi, and 2-(N,N-dimethylamino)benzyl, and
• X' is a neutral, conjugated or nonconjugated diene, optionally substituted with one or more hydrocarbyl groups, said X' having up to 40 carbon atoms and forming a ⁇ -complex with M.
• Most preferred metal complexes are those according to the previous formula (II) or (III), wherein M, X, X', X", R' R", Z*, Y, p, q and r are as previously defined, with the proviso that:
• X is a 1 ,4- butadienyl group that forms a metallocyclopentene ring with M
• Especially preferred coordination complexes corresponding to the previous formulas (II) and (III) are uniquely substituted depending on the particular end use thereof.
• highly useful metal complexes for use in catalyst compositions for the copolymerization of ethylene, one or more monovinyl aromatic monomers, and optionally an ⁇ -olefin or diolefin comprise the foregoing complexes (II) or (III) wherein R' is Cg_20 ar l. especially phenyl, biphenyl or naphthyl, and R" is hydrogen or methyl, especially hydrogen.
• Highly useful metal complexes for use in catalyst compositions for the homopolymerization of ethylene or the copolymerization of ethylene and one or more ⁇ -olefins, especially 1-butene, 1-hexene or 1-octene comprise the foregoing complexes (II) or (III) wherein R' is C ⁇ _4 alkyl, N,N-dimethylamino or 1-pyrrolidinyl, and R" is hydrogen or C- j .4 alkyl.
• Y is preferably a cyclohexylamido group
• X is methyl
• p is two
• both q and r are zero.
• complexes are 2,3-dimethyl-substituted s- indecenyl complexes corresponding to the formulas:
• highly useful metal complexes for use in catalyst compositions for the copolymerization of ethylene, an ⁇ -olefin and a diene, especially ethylene, propylene and a nonconjugated diene, such as ethylidenenorbornene or 1 ,4-hexadiene, or the conjugated diene piperylene comprise the foregoing complexes (II) or (III) wherein R' is hydrogen, and R" is C-
• 3-methylindenyl complexes (n-butylamido)dimethyl( ⁇ 5 -3-methylindenyl)silanetitanium (II) 1 ,4-diphenyl-1 ,3-butadiene, (n-butylamido)dimethyl( ⁇ 5 -3-methylindenyl)silanetitanium (II) 1 ,3-pentadiene, (n-butylamido)dimethyl( ⁇ 5 -3-methylindenyl)silanetitanium (lll) 2-(N,N-dimethylamino)benzyl, (n-butylamido)dimethyl( ⁇ 5 -3-methylindenyl)silanetitanium (IV) dimethyl, (n-butylamido)dimethyl( ⁇ 5 -3-methylindenyl)silanetitanium (IV) dibenzyl,
• 2-methyl-s-indacen-1 -yl complexes (n-butylamido)dimethyl( ⁇ 5 -2-methyl-s-indacen-1-yl)silanetitanium (II) 1 ,4-diphenyl-1 ,3- butadiene,
• 2,3-dimethyl-s-indacen-1-yl complexes (n-butylamido)dimethvl( ⁇ 5 -2,3-dimethyl-s-indacen-1- yl)silanetitanium (II) 1 ,4-diphenyl-1 ,3-butadiene,
• the complexes can be prepared by use of well known synthetic techniques.
• a reducing agent can be employed to produce the lower oxidation state complexes.
• a suitable noninterfering solvent at a temperature from -100 to 300 °C, preferably from -78 to 100 °C, most preferably from 0 to 50 °C.
• reducing agent herein is meant a metal or compound which, under reducing conditions causes the metal, M, to be reduced from a higher to a lower oxidation state.
• suitable metal reducing agents are alkali metals, alkaline earth metals, aluminum and zinc, alloys of alkali metals or alkaline earth metals such as sodium/mercury amalgam and sodium/potassium alloy.
• suitable reducing agent compounds are sodium naphthalenide, potassium graphite, lithium alkyls, lithium or potassium alkadienyls; and Grignard reagents.
• Most preferred reducing agents are the alkali metals or alkaline earth metals, especially lithium and magnesium metal.
• Suitable reaction media for the formation of the complexes include aliphatic and aromatic hydrocarbons, ethers, and cyclic ethers, particularly branched-chain hydrocarbons such as isobutane, butane, pentane, hexane, heptane, octane, and mixtures thereof; cyclic and alicyclic hydrocarbons such as cyclohexane, cycloheptane, methylcyclohexane, methylcycloheptane, and mixtures thereof; aromatic and hydrocarbyl-substituted aromatic compounds such as benzene, toluene, and xylene, C ⁇ dialkyl ethers, C ⁇ dialkyl ether derivatives of (poly)alkylene glycols, and tetrahydrofuran. Mixtures of the foregoing are also suitable.
• the complexes are rendered catalytically active by combination with an activating cocatalyst or by use of an activating technique.
• Suitable activating cocatalysts for use herein include polymeric or oligomeric alumoxanes, especially methylalumoxane, triisobutyl aluminum modified methylalumoxane, or isobutyialumoxane; neutral Lewis acids, such as C ⁇ .
• hydrocarbyl substituted Group 13 compounds especially tri(hydrocarbyl)aluminum- or tri(hydrocarbyl)boron compounds and halogenated (including perhalogenated) derivatives thereof, having from 1 to 10 carbons in each hydrocarbyl or halogenated hydrocarbyl group, more especially perfluorinated tri(aryl)boron compounds, and most especially tris(pentafluoro- phenyl)borane; nonpolymeric, compatible, noncoordinating, ion forming compounds (including the use of such compounds under oxidizing conditions), especially the use of ammonium-, phosphonium-, oxonium-, carbonium-, silylium- or sulfonium- salts of compatible, noncoordinating anions, or ferrocenium salts of compatible, noncoordinating anions; bulk electrolysis (explained in more detail hereinafter); and combinations of the foregoing activating cocatalysts and techniques.
• Combinations of neutral Lewis acids especially the combination of a trialkyi aluminum compound having from 1 to 4 carbons in each alkyl group and a halogenated tri(hydrocarbyl)boron compound having from 1 to 20 carbons in each hydrocarbyl group, especially tris(pentafluorophenyl)borane, further combinations of such neutral Lewis acid mixtures with a polymeric or oligomeric alumoxane, and combinations of a single neutral Lewis acid, especially tris(pentafluorophenyl)borane with a polymeric or oligomeric alumoxane are especially desirable activating cocatalysts.
• a benefit according to the present invention is the discovery that the most efficient catalyst activation using such a combination of tris(pentafluoro- phenyl)borane/alumoxane mixture occurs at reduced levels of alumoxane.
• Preferred molar ratios of Group 4 metal complex:tris(pentafluoro-phenylborane:alumoxane are from 1 :1:1 to 1:5:5, more preferably from 1 :1 :1.5 to 1 :5:3.
• Suitable ion forming compounds useful as cocatalysts in one embodiment of the present invention comprise a cation which is a Bronsted acid capable of donating a proton, and a compatible, noncoordinating anion, A " .
• noncoordinating means an anion or substance which either does not coordinate to the Group 4 metal containing precursor complex and the catalytic derivative derived therefrom, or which is only weakly coordinated to such complexes thereby remaining sufficiently labile to be displaced by a neutral Lewis base.
• a noncoordinating anion specifically refers to an anion which when functioning as a charge balancing anion in a cationic metal complex does not transfer an anionic substituent or fragment thereof to said cation thereby forming neutral complexes.
• “Compatible anions” are anions which are not degraded to neutrality when the initially formed complex decomposes and are noninterfering with desired subsequent polymerization or other uses of the complex.
• Preferred anions are those containing a single coordination complex comprising a charge-bearing metal or metalloid core which anion is capable of balancing the charge of the active catalyst species (the metal cation) which may be formed when the two components are combined. Also, said anion should be sufficiently labile to be displaced by olefinic, diolefinic and acetylenically unsaturated compounds or a neutral Lewis base such as an ether or nitrile.
• Suitable metals include, but are not limited to, aluminum, gold and platinum.
• Suitable metalloids include, but are not limited to, boron, phosphorus, and silicon.
• Compounds containing anions which comprise coordination complexes containing a single metal or metalloid atom are, of course, well known and many, particularly such compounds containing a single boron atom in the anion portion, are available commercially.
• cocatalysts may be represented by the following general formula: (L*-H) d + (A) d - wherein:
• L * is a neutral Lewis base
• (L*-H)+ is a Bronsted acid
• a d" is a noncoordinating, compatible anion having a charge of d-, and d is an integer from 1 to 3.
• a d" corresponds to the formula: [M'Q 4 ] " ; wherein: M' is boron or aluminum in the +3 formal oxidation state; and
• Q independently each occurrence is selected from hydride, dialkylamido, halide, hydrocarbyl, hydrocarbyloxide, halosubstituted-hydrocarbyl, halosubstituted hydrocarbyloxy, and halo- substituted silylhydrocarbyl radicals (including perhalogenated hydrocarbyl- perhalogenated hydrocarbyloxy- and perhalogenated silylhydrocarbyl radicals), said Q having up to 20 carbons with the proviso that in not more than one occurrence is Q halide.
• suitable hydrocarbyloxide Q groups are disclosed in U. S. Patent 5,296,433.
• d is one, that is, the counter ion has a single negative charge and is A " .
• Activating cocatalysts comprising boron which are particularly useful in the preparation of catalysts of this invention may be represented by the following general formula: (L*-H) + (BQ 4 )-; wherein:
• B is boron in a formal oxidation state of 3
• Q is a hydrocarbyl-, hydrocarbyloxy-, fluorinated hydrocarbyl-, fluorinated hydrocarbyloxy-, or fluorinated silylhydrocarbyl- group of up to 20 nonhydrogen atoms, with the proviso that in not more than one occasion is Q hydrocarbyl.
• Q is each occurrence a fluorinated aryl group, especially, a pentafluorophenyl group.
• N,N-dimethyl-2,4,6-trimethylanilinium tetrakis(pentafluorophenyl) borate trimethylammonium tetrakis(2,3,4,6-tetrafluorophenyl)borate, triethylammonium tetrakis(2,3,4,6-tetrafluorophenyl) borate, tripropylammonium tetrakis(2,3,4,6-tetrafluorophenyl) borate, tri(n-butyl)ammonium tetrakis(2,3,4,6-tetrafluorophenyl) borate, dimethyl(t-butyl)ammonium tetrakis(2,3,4,6-tetrafluorophenyl) borate,
• dialkyl ammonium salts such as: di-(i-propyl)ammonium tetrakis(pentafluorophenyl) borate, and dicyclohexylammonium tetrakis(pentafluorophenyl) borate; tri-substituted phosphonium salts such as: triphenylphosphonium tetrakis(pentafluorophenyl) borate, tri(o-tolyl)phosphonium tetrakis(pentafluorophenyl) borate, and tri(2,6-dimethylphenyl)phosphonium tetrakis(pentafluorophenyl) borate; di-substituted oxonium salts such as: diphenyioxonium tetra
• Preferred (L * -H) + cations are N,N-dimethyianilinium and tributylammonium.
• Another suitable ion forming, activating cocatalyst comprises a salt of a cationic oxidizing agent and a noncoordinating, compatible anion represented by the formula:
• Ox e+ is a cationic oxidizing agent having a charge of e+; e is an integer from 1 to 3; and
• a d" and d are as previously defined.
• cationic oxidizing agents include: ferrocenium, hydrocarbyl-substituted ferrocenium, Ag + ⁇ or Pb +2 .
• Preferred embodiments of A d" are those anions previously defined with respect to the Bronsted acid containing activating cocatalysts, especially tetrakis(pentafluorophenyl)borate.
• Another suitable ion forming, activating cocatalyst comprises a compound which is a salt of a carbenium ion and a noncoordinating, compatible anion represented by the formula:
• ⁇ + is a C.,. 20 carbenium ion
• a " is as previously defined.
• a preferred carbenium ion is the trityl cation, that is triphenylmethylium.
• a further suitable ion forming, activating cocatalyst comprises a compound which is a salt of a silylium ion and a noncoordinating, compatible anion represented by the formula: R 3 Si(X') q + A- wherein:
• R is C,_ 10 hydrocarbyl, and X', q and A " are as previously defined.
• silylium salt activating cocatalysts are trimethylsilylium tetrakispentafluorophenylborate, triethylsilylium tetrakispentafluorophenylborate and ether substituted adducts thereof.
• Silylium salts have been previously generically disclosed in J. Chem Soc. Chem. Comm., 1993, 383-384, as well as Lambert, J. B., et al., Organometallics, 1994, 13, 2430-2443.
• the use of the above silylium salts as activating cocatalysts for addition polymerization catalysts is claimed in USP 5,625,087.
• cocatalysts will comprise a cation which is a Bronsted acid capable of donating a proton, and an inert, compatible, noncoordinating, anion, characterized by a solubility at 25 °C in hexane, cyclohexane or methylcyclohexane of at least 5 weight percent, preferably at least 7.5 weight percent.
• improved catalyst activation is provided. More particularly, increased catalyst efficiency and rate of polymerization are obtained, especially under solution polymerization conditions, most especially continuous, solution polymerization conditions.
• Preferred embodiments of such cocatalysts may be represented by the following general formula: (L * -H) Cj + (A c '"), wherein:
• L * is a neutral Lewis base
• (L * -H) + is a Bronsted acid
• a d ⁇ is a noncoordinating, compatible anion having charge d-, and d is an integer from 1 to 3.
• Suitable anions of the formula A d" include sterically shielded diboron anions corresponding to the formula:
• S is alkyl, fluoroalkyl, aryl, or fluoroaryl ( and where two S groups are present additionally hydrogen),
• Ar F is fluoroaryl
• X 1 is either hydrogen or halide.
• diboron anions are disclosed in US-A-5,447,895.
• M' is an element selected from Group 13 of the Periodic Table of the Elements.
• Q independently each occurrence is selected from hydride, dialkylamido, halide, alkoxide, aryloxide, hydrocarbyl, and halosubstituted-hydrocarbyl radicals, said Q having up to 20 carbons with the proviso that in not more than one occurrence is Q halide.
• d is one, that is, the counter ion has a single negative charge and corresponds to the formula, A".
• Activating cocatalysts comprising boron which are particularly useful in this invention may be represented by the following general formula: [L * -H] + [BQ'4] " , wherein:
• L* is a nitrogen, sulfur or phosphorus containing neutral Lewis base
• B is boron in an oxidation state of 3
• Q' is a fluorinated C-
• Q' is in each occurrence a fluorinated aryl group, especially a pentafluorophenyl group.
• solubility of the catalyst activators of the invention in aliphatic compounds is increased by incorporation of one or more oleophilic groups such as long chain alkyl groups; long chain alkenyl groups; or halo-, alkoxy-, amino-, silyl-, or germyl- substituted long chain alkyl groups or long chain alkenyl groups into the Bronsted acid, L.
• long chain are meant groups having from 10 to 50 non-hydrogen atoms in such group, preferably in a non- branched form.
• such L groups contain from 1 to 3 C 1 ⁇ M0 n-alkyl groups with a total of from 12 to 100 carbons, more preferably 2 C 1(M0 alkyl groups and from 21 to 90 total carbons.
• the presence of such oleophilic groups is believed to render the activator more soluble in aliphatic liquids thereby improving the effectiveness in catalyst activation.
• the catalyst activator may comprise a mixture of oleophilic groups of differing lengths.
• one suitable activator is the protonated ammonium salt derived from the commercially available long chain amine comprising a mixture of two C 14 , C 16 or C 18 alkyl groups and one methyl group.
• Such amines are available from Witco Corp., under the trade name KemamineTM T9701 , and from Akzo-Nobel under the trade name ArmeenTM M2HT.
• the present cocatalysts may be used in reduced concentrations based on amount of metal complex compared to the amounts of prior known cocatalysts previously required, while retaining equivalent or improved catalyst efficiencies.
• N-methyl-N-dodecylanilinium tetrakis(pentafluorophenyl) borate N,N-di(octadecyl)(2,4,6-trimethylanilinium) tetrakis(pentafluorophenyl) borate, cyclohexyldi(dodecyl)ammonium tetrakis(pentafluorophenyl)borate, and methyldi(dodecyl)ammonium tetrakis-(2,3,4,6-tetrafluorophenyl) borate.
• Suitable similarly substituted sulfonium or phosphonium salts such as, di(decyl)sulfonium tetrakis(pentafluorophenyl) borate, (n-butyl)dodecylsulfonium tetrakis(pentafluorophenyl) borate, tridecylphosphonium tetrakis(pentafluorophenyl) borate, di(octadecyl)methylphosphonium tetrakis(pentafluorophenyl) borate, and tri(tetradecyl)phosphonium tetrakis(pentafluorophenyl) borate, may also be named.
• Preferred activators are di(octadecyl)methylammonium tetrakis(pentafluorophenyl)borate and di(octadecyl)(n-butyl)ammonium tetrakis(pentafluorophenyl)borate.
• the cocatalysts may also be used in combination with a tri(hydrocarbyl)aluminum compound having from 1 to 10 carbons in each hydrocarbyl group, an oligomeric or polymeric alumoxane compound, a di(hydrocarbyl)(hydrocarbyloxy)aluminum compound having from 1 to 20 carbons in each hydrocarbyl or hydrocarbyloxy group, or a mixture of the foregoing compounds, if desired.
• These aluminum compounds are usefully employed for their beneficial ability to scavenge impurities such as oxygen, water, and aldehydes from the polymerization mixture.
• Suitable di(hydrocarbyl)(hydrocarbyloxy)aluminum compounds correspond to the formula T 1 2 AIOT 2 wherein T 1 is C 3 ⁇ secondary or tertiary alkyl, most preferably isopropyl, isobutyl or tert-butyl; and T 2 is a C 12 .
• alkaryl radical or aralkyl radical most preferably, 2,6-di(t- butyl)-4-methylphenyl, 2,6-di(t-butyl)-4-methyltolyl, 2,6-di(i-butyl)-4-methylphenyl, or 4-(3',5'- ditertiarybutyltolyl)-2,6-ditertiarybutylphenyl.
• Preferred aluminum compounds include C2-6 trialkyl aluminum compounds, especially those wherein the alkyl groups are ethyl, propyl, isopropyl, n-butyl, isobutyl, pentyl, neopentyl, or isopentyl, dialkyl(aryloxy)aluminum compounds containing from 1-6 carbons in the alkyl group and from 6 to 18 carbons in the aryl group (especially (3,5-di(t-butyl)-4- methylphenoxy)diisobutylaluminum), methylalumoxane, modified methylalumoxane and diisobutylalumoxane.
• the molar ratio of aluminum compound to metal complex is preferably from 1 :10,000 to 1000:1 , more preferably from 1:5000 to 100:1 , most preferably from 1 :100 to 100:1.
• the technique of bulk electrolysis involves the electrochemical oxidation of the metal complex under electrolysis conditions in the presence of a supporting electrolyte comprising a noncoordinating, inert anion.
• solvents, supporting electrolytes and electrolytic potentials for the electrolysis are used such that electrolysis byproducts that would render the metal complex catalytically inactive are not substantially formed during the reaction.
• suitable solvents are materials that are: liquids under the conditions of the electrolysis (generally temperatures from 0 to 100 °C), capable of dissolving the supporting electrolyte, and inert.
• “Inert solvents” are those that are not reduced or oxidized under the reaction conditions employed for the electrolysis.
• a solvent and a supporting electrolyte that are unaffected by the electrical potential used for the desired electrolysis.
• Preferred solvents include difluorobenzene (all isomers), dimethoxyethane (DME), and mixtures thereof.
• the electrolysis may be conducted in a standard electrolytic cell containing an anode and cathode (also referred to as the working electrode and counter electrode respectively). Suitable materials of construction for the cell are glass, plastic, ceramic and glass coated metal.
• the electrodes are prepared from inert conductive materials, by which are meant conductive materials that are unaffected by the reaction mixture or reaction conditions. Platinum or palladium are preferred inert conductive materials.
• an ion permeable membrane such as a fine glass frit separates the cell into separate compartments, the working electrode compartment and counter electrode compartment.
• the working electrode is immersed in a reaction medium comprising the metal complex to be activated, solvent, supporting electrolyte, and any other materials desired for moderating the electrolysis or stabilizing the resulting complex.
• the counter electrode is immersed in a mixture of the solvent and supporting electrolyte.
• the desired voltage may be determined by theoretical calculations or experimentally by sweeping the cell using a reference electrode such as a silver electrode immersed in the cell electrolyte.
• the background cell current the current draw in the absence of the desired electrolysis, is also determined.
• the electrolysis is completed when the current drops from the desired level to the background level. In this manner, complete conversion of the initial metal complex can be easily detected.
• Suitable supporting electrolytes are salts comprising a cation and a compatible, noncoordinating anion, A-.
• Preferred supporting electrolytes are salts corresponding to the formula G + A " ; wherein: G + is a cation which is nonreactive towards the starting and resulting complex, and
• a " is as previously defined.
• Examples of cations, G + include tetrahydrocarbyl substituted ammonium or phosphonium cations having up to 40 nonhydrogen atoms. Preferred cations are the tetra(n- butylammonium)- and tetraethylammonium- cations.
• Preferred supporting electrolytes are tetrahydrocarbylammonium salts of tetrakis(perfluoroaryl) borates having from 1 to 10 carbons in each hydrocarbyl or perfluoroaryl group, especially tetra(n- butylammonium)tetrakis(pentafluorophenyl) borate.
• a further recently discovered electrochemical technique for generation of activating cocatalysts is the electrolysis of a disilane compound in the presence of a source of a noncoordinating compatible anion. This technique is more fully disclosed and claimed in the previously mentioned USP 5,625,087.
• electrochemical activating technique and activating cocatalysts may also be used in combination.
• An especially preferred combination is a mixture of a tri(hydrocarbyl)aluminum or tri(hydrocarbyl)borane compound having from 1 to 4 carbons in each hydrocarbyl group with an oligomeric or polymeric alumoxane compound.
• the molar ratio of catalyst/cocatalyst employed preferably ranges from 1:10,000 to 100:1 , more preferably from 1:5000 to 10:1, most preferably from 1 :1000 to 1 :1.
• Alumoxane when used by itself as an activating cocatalyst, is employed in large quantity, generally at least 100 times the quantity of metal complex on a molar basis.
• Tris(pentafluorophenyl)borane, where used as an activating cocatalyst is employed in a molar ratio to the metal complex of form 0.5:1 to 10:1, more preferably from 1 :1 to 6:1 most preferably from 1 :1 to 5:1.
• the remaining activating cocatalysts are generally employed in approximately equimolar quantity with the metal complex.
• the process may be used to polymerize ethylenically unsaturated monomers having from 3 to 20 carbon atoms either alone or in combination.
• Preferred monomers include monovinylidene aromatic monomers, 4-vinyicyclohexene, vinylcyclohexane, norbornadiene and C 3 . 10 aliphatic ⁇ -olefins (especially ethylene, propylene, isobutylene, 1-butene, 1-hexene, 3- methy 1-1 -pentene, 4-methyl-1 -pentene, and 1-octene), C 4 _ 40 dienes, and mixtures thereof.
• Most preferred monomers are ethylene, and mixtures of ethylene, propylene and a nonconjugated diene, especially ethylidenenorbornene.
• the polymerization may be accomplished at conditions well known in the prior art for Ziegler-Natta or Kaminsky-Sinn type polymerization reactions, that is, temperatures from 0 to 250 °C, preferably 30 to 200 °C and pressures from atmospheric to 10,000 atmospheres (1000 MPa). Suspension, solution, slurry, gas phase, solid state powder polymerization or other process condition may be employed if desired.
• a support, especially silica, alumina, or a polymer (especially poly(tetrafluoroethylene) or a polyolefin) may be employed, and desirably is employed when the catalysts are used in a gas phase polymerization process.
• the support is preferably employed in an amount to provide a weight ratio of catalyst (based on metal):support from 1:100,000 to 1 :10, more preferably from 1 :50,000 to 1 :20, and most preferably from 1 :10,000 to 1 :30.
• the molar ratio of catalyst: poly merizable compounds employed is from 10 "1 :1 to 10 "1 :1 , more preferably from 10 9 : 1 to 10 5 :1.
• Suitable solvents for polymerization are inert liquids.
• examples include straight and branched-chain hydrocarbons such as isobutane, butane, pentane, hexane, heptane, octane, and mixtures thereof; cyclic and alicyclic hydrocarbons such as cyclohexane, cycloheptane, methylcyclohexane, methylcycloheptane, and mixtures thereof; perfluorinated hydrocarbons such as perfluorinated C 4 . 10 alkanes, and aromatic and alkyl-substituted aromatic compounds such as benzene, toluene, xylene, and ethylbenzene and the like.
• Suitable solvents also include liquid olefins which may act as monomers or comonomers including ethylene, propylene, butadiene, cyclopentene, 1-hexene, 1 -hexane, 4-vinylcyclohexene, vinylcyclohexane, 3-methyl-1 -pentene, 4-methy 1-1 -pentene, 1,4-hexadiene, 1-octene, 1-decene, styrene, divinylbenzene, allylbenzene, and vinyltoluene (including all isomers alone or in admixture), and the like. Mixtures of the foregoing are also suitable.
• the catalysts may be utilized in combination with at least one additional homogeneous or heterogeneous polymerization catalyst in separate reactors connected in series or in parallel to prepare polymer blends having desirable properties.
• An example of such a process is disclosed in WO 94/00500, equivalent to U. S. Serial Number 07/904,770, as well as WO 94/17112, equivalent to U. S. Serial Number 08/10958, filed January 29, 1993.
• the polymers of the present invention will preferably have high levels of long chain branching.
• the use of the catalysts described herein in the production of the polymers of the present invention in continuous polymerization processes, especially continuous, solution polymerization processes, allows for elevated reactor temperatures which favor the formation of vinyl terminated polymer chains that may be incorporated into a growing polymer, thereby giving a long chain branch.
• the use of the catalysts described herein in the production of the polymers of the present invention advantageously allows for the economical production of ethylene/ ⁇ -olefin copolymers having processability similar to high pressure, free radical produced low density polyethylene.
• the polymers of the present invention will preferably have at least 0.03 , more preferably at least 0.04 vinyls/1000 carbons, as determined by FTIR .
• the polymers of the invention will preferably be characterized as having long chain branching, preferably from 0.01 to 3 long chain branches/1000 carbons. Methods for determining the amount of long chain branching present, both qualitatively and quantitatively, are known in the art.
• Preferred polymers of the present invention will possess a gas extrusion rheology such that: (a) the critical shear rate at the onset of surface melt fracture for the inventive polymer is at least 50 percent greater than the critical shear rate at the onset of surface melt fracture for a linear polymer having the same comonomer or comonomers and having an I2, M w /M n and density within ten percent of that of the inventive polymer, and wherein the respective critical shear rates of the inventive polymer and the linear polymer are measured at the same melt temperature using a gas extrusion rheometer; or (b) the critical shear rate at the onset of gross melt fracture is greater than 4 x 10 6 dynes/cm 2 , as determined by gas extrusion rheometry.
• inventive polymers are further characterized as having a melt flow ratio (IIQ/'2) which may be varied independently of the polydispersity index, that is, the molecular weight distribution M w /M n .
• IIQ/'2 melt flow ratio
• M w /M n molecular weight distribution
• the polymers of the invention will have an l 10 /l 2 which is at least 10, preferably at least 15, with l 10 /l 2 values exceeding 20 being possible.
• ATREF/DV may be further used to illustrate the fact that the preferred copolymers of the invention are characterized as having a bimodal molecular weight distribution. It is significant to note that the ATREF peaks are quite sharp, and are distinguishable from copolymers which are produced using supported catalyst systems. Specifically, (i) the maximum ATREF peak height is measured, (ii) the width of the total ATREF peak at V 2 the maximum peak height is measured, the ATREF shape factor is calculated, that is, the ratio (ii)/(i), and the average ATREF elution temperature is determined, that is, (minimum ATREF elution temp + maximum ATREF elution temp)/2.
• the polymers of the invention will be characterized as having an ATREF curve which satisfies the following inequality:
• ATREF Shape Factor ⁇ 0.75 - 0.00626 Average Elution Temperature
• ATREF Shape Factor ⁇ 0.70 - 0.00626 Average Elution Temperature
• the polymer compositions of the invention are characterized as having a fraction which has a higher crystallinity than the other fraction.
• the presence of the higher crystallinity fraction translates to an enhancement in the upper service temperature of the polymer compositions of the invention, with respect to the comparative compositions.
• the upper service temperature may be defined as the intersection of a line drawn across the upper non-melted plateau region and the descending melting transition region of the log G1 versus temperature plot.
• the upper service temperature of the olefin interpolymer is greater than the upper service temperature of a physical blend (UST (blend)) of a first homogeneous olefin polymer having a density equal to the first density, an l 2 equal to the first l 2 , and which is provided in the first weight percent, and a second homogeneous olefin polymer having a density equal to the second density, an l 2 equal to the second l 2 , and which is provided in the second weight percent, in accordance with the following inequality: UST (interpolymer) - UST (blend) > 256 - 275 (density of olefin interpolymer).
• the polymers of the present invention will preferably have improved processing properties, whether they result from polymerizing ethylene alone or ethylene/ ⁇ -olefin mixtures with low levels of a "H" branch inducing diene, such as norbornadiene, 1 ,7-octadiene, or 1 ,9- decadiene.
• a "H" branch inducing diene such as norbornadiene, 1 ,7-octadiene, or 1 ,9- decadiene.
• the unique combination of elevated reactor temperatures, high molecular weight (or low melt indices) at high reactor temperatures and high comonomer reactivity advantageously allows for the economical production of polymers having excellent physical properties and processability.
• such polymers comprise ethylene, a C 3 - 20 ⁇ -olefin and a "H"-branching comonomer.
• such polymers are produced in a solution process, most preferably a continuous solution process.
• the polymers of the present invention may be prepared via a solution or slurry process both of which are previously known in the art.
• Kaminsky, 1_ Poly. Sci., Vol. 23, pp. 2151-64 (1985) reported the use of a soluble bis(cyclopentadienyl) zirconium dimethyl-alumoxane catalyst system for solution polymerization of EP and EPDM elastomers.
• USP 5,229,478 disclosed a slurry polymerization process utilizing similar bis(cyclopentadienyl) zirconium based catalyst systems.
• an olefin polymerization catalyst to a diene, especially the high concentrations of diene monomer required to produce the requisite level of diene incorporation in the final EPDM product, often reduces the rate or activity at which the catalyst will cause polymerization of ethylene and propylene monomers to proceed.
• lower throughputs and longer reaction times have been required, compared to the production of an ethylene-propyiene copolymer elastomer or other ⁇ -olefin copolymer elastomer.
• the present catalyst system advantageously allows for increased diene reactivity thereby preparing EPDM polymers in high yield and productivity. Additionally, the catalyst system of the present invention achieves the economical production of EPDM polymers with diene contents of up to 20 weight percent or higher, which polymers possess highly desirable fast cure rates.
• the non-conjugated diene monomer can be a straight chain, branched chain or cyclic hydrocarbon diene having from 6 to 15 carbon atoms.
• suitable non-conjugated dienes are straight chain acyclic dienes such as 1 ,4-hexadiene and 1 ,6-octadiene: branched chain acyclic dienes such as 5-methyl-1 ,4-hexadiene; 3,7-dimethyl-1 ,6-octadiene; 3,7-dimethyl- 1 ,7-octadiene and mixed isomers of dihydromyricene and dihydroocinene: single ring alicyclic dienes such as 1 ,3-cyclopentadiene; 1 ,4-cyclohexadiene; 1 ,5-cyclooctadiene and 1 ,5- cyclododecadiene: and multi-ring alicyclic fused and bridged ring dienes such as
• the especially preferred dienes are 5-ethylidene-2-norbornene (ENB) and 1 ,4-hexadiene (HD).
• Another preferred diene is piperylene.
• the preferred EPDM elastomers may contain 20 up to 90 weight percent ethylene, more preferably 30 to 85 weight percent ethylene, most preferably 35 to 80 weight percent ethylene.
• the alpha-olefins suitable for use in the preparation of elastomers with ethylene and dienes are preferably C 3 . 1 ⁇ alpha-olefins. Illustrative non-limiting examples of such alpha-olefins are propylene, 1-butene, 1 -pentene, 1-hexene, 1-octene, 1-decene, and 1-dodecene.
• the alpha-olefin is generally incorporated into the EPDM polymer at 10 to 80 weight percent, more preferably at 20 to 65 weight percent.
• the non-conjugated dienes are generally incorporated into the EPDM at 0.5 to 20 weight percent; more, preferably at 1 to 15 weight percent, and most preferably at 3 to 12 weight percent. If desired, more than one diene may be incorporated simultaneously, for example HD and ENB, with total diene incorporation within the limits specified above.
• the catalyst system may be prepared as a homogeneous catalyst by addition of the requisite components to a solvent in which polymerization will be carried out by solution polymerization procedures.
• the catalyst system may also be prepared and employed as a heterogeneous catalyst by adsorbing the requisite components on a catalyst support material such as silica gel, alumina or other suitable inorganic support material.
• a catalyst support material such as silica gel, alumina or other suitable inorganic support material.
• silica silica as the support material.
• the heterogeneous form of the catalyst system is employed in a slurry polymerization. As a practical limitation, slurry polymerization takes place in liquid diluents in which the polymer product is substantially insoluble.
• the diluent for slurry polymerization is one or more hydrocarbons with less than 5 carbon atoms.
• saturated hydrocarbons such as ethane, propane or butane may be used in whole or part as the diluent.
• ⁇ -olefin monomer or a mixture of different ⁇ -olefin monomers may be used in whole or part as the diluent.
• the diluent comprises in at least major part the ⁇ -olefin monomer or monomers to be polymerized.
• solution polymerization conditions utilize a solvent for the respective components of the reaction, particularly the EP or EPDM polymer.
• Preferred solvents include mineral oils and the various hydrocarbons which are liquid at reaction temperatures.
• Illustrative examples of useful solvents include alkanes such as pentane, iso-pentane, hexane, heptane, octane and nonane, as well as mixtures of alkanes including kerosene and Isopar ETM, available from Exxon Chemicals Inc.; cycloalkanes such as cyclopentane and cyclohexane; and aromatics such as benzene, toluene, xylenes, ethylbenzene and diethylbenzene.
• the individual ingredients as well as the recovered catalyst components must be protected from oxygen and moisture. Therefore, the catalyst components and catalysts must be prepared and recovered in an oxygen and moisture free atmosphere. Preferably, therefore, the reactions are performed in the presence of an dry, inert gas such as, for example, nitrogen.
• Ethylene is added to the reaction vessel in an amount to maintain a differential pressure in excess of the combined vapor pressure of the ⁇ -olefin and diene monomers.
• the ethylene content of the polymer is determined by the ratio of ethylene differential pressure to the total reactor pressure.
• the polymerization process is carried out with a differential pressure of ethylene of from 10 to 1000 psi (70 to 7000 kPa), most preferably from 40 to 400 psi (30 to 300 kPa).
• the polymerization is generally conducted at a temperature of from 25 to 200 °C, preferably from 75 to 170 °C, and most preferably from greater than 95 to 140 °C.
• the polymerization may be carried out as a batchwise or a continuous polymerization process.
• a continuous process is preferred, in which event catalyst, ethylene, ⁇ -olefin, and optionally solvent and diene are continuously supplied to the reaction zone and polymer product continuously removed therefrom.
• event catalyst, ethylene, ⁇ -olefin, and optionally solvent and diene are continuously supplied to the reaction zone and polymer product continuously removed therefrom.
• one means for carrying out such a polymerization process is as follows. In a stirred-tank reactor propylene monomer is introduced continuously together with solvent, diene monomer and ethylene monomer. The reactor contains a liquid phase composed substantially of ethylene, propylene and diene monomers together with any solvent or additional diluent.
• a small amount of a "H"- branch inducing diene such as norbornadiene, 1 ,7-octadiene or 1 ,9-decadiene may also be added.
• Catalyst and cocatalyst are continuously introduced in the reactor liquid phase.
• the reactor temperature and pressure may be controlled by adjusting the solvent/monomer ratio, the catalyst addition rate, as well as by cooling or heating coils, jackets or both.
• the polymerization rate is controlled by the rate of catalyst addition.
• the ethylene content of the polymer product is determined by the ratio of ethylene to propylene in the reactor, which is controlled by manipulating the respective feed rates of these components to the reactor.
• the polymer product molecular weight is controlled, optionally, by controlling other polymerization variables such as the temperature, monomer concentration, or by a stream of hydrogen introduced to the reactor, as is well known in the art.
• the reactor effluent is contacted with a catalyst kill agent such as water.
• the polymer solution is optionally heated, and the polymer product is recovered by flashing off gaseous ethylene and propylene as well as residual solvent or diluent at reduced pressure, and, if necessary, conducting further devolatilization in equipment such as a devolatilizing extruder.
• the mean residence time of the catalyst and polymer in the reactor generally is from 5 minutes to 8 hours, and preferably from 10 minutes to 6 hours.
• the polymerization is conducted in a continuous solution polymerization system comprising two reactors connected in series or parallel.
• a product having a molecular weight (M w ) of from 300,000 to 600,000, more preferably 400,000 to 500,000 is formed while in the second reactor a product of a second molecular weight (M w ) of 50,000 to 300,000) is formed.
• M w molecular weight
• the final product is a blend of the two reactor effluents which are combined prior to devolatilization to result in a uniform blend of the two polymer products.
• Such a dual reactor process allows for the preparation of products having improved properties.
• the reactors are connected in series, that is effluent from the first reactor is charged to the second reactor and fresh monomer, solvent and hydrogen is added to the second reactor.
• Reactor conditions are adjusted such that the weight ratio of polymer produced in the first reactor to that produced in the second reactor is from 20:80 to 80:20.
• the temperature of the second reactor is controlled to produce the lower molecular weight product.
• the Mooney viscosity (ASTM D1646-94, ML1+4 at 125 °C) of the resulting product is adjusted to fall in the range from 1 to 200, preferably from 5 to 150, and most preferably from 10 to 110.
• Dimethylsilyl(2,3,4,6-tetramethylindenyl)CI (22.29 grams, 84.17 mmol) was stirred in THF as i-PrNH 2 (28.68 mL, 336.7 mmol) was added. The mixture was stirred for 16 hours. The volatiles were removed under reduced pressure. The residue was extracted with hexane and filtered through a diatomaceous earth filter aid on a 10-15 mm glass frit. The hexane was removed under reduced pressure to afford the product as a yellow oil. Yield; 17.23 grams, 71 percent.
• Dimethyisilyl(2,3,4,6-tetramethylindenyl)CI (9..95g, 37.8 mmol) was stirred in hexane (200 mL) as NEt.3 (4.1 g, 40.6 mmol) was added followed by cyclohexylamine (4.05g, 40.8 mmol). This mixture was allowed to stir for 24 hours at 20°C. After the reaction period the mixture was filtered and the desired product isolated as a pale yellow oil following the removal of the volatiles (10.98 g, 89.3 percent yield).
• the apparatus (referred to as R-1) was set-up in the hood and purged with nitrogen; it consisted of a 10 L glass kettle with flush mounted bottom valve, 5-neck head, polytetrafluoroethylene gasket, clamp, and stirrer components (bearing, shaft, and paddle).
• the necks were equipped as follows: stirrer components were put on the center neck, and the outer necks had a reflux condenser topped with gas inlet/outlet, an inlet for solvent, a thermocouple, and a stopper. Dry, deoxygenated dimethoxyethane (DME) was added to the flask (approx. 5.2 L).
• DME deoxygenated dimethoxyethane
• the apparatus (referred to as R-2) was set-up as described for R-1 , except that flask size was 30 L.
• the head was equipped with seven necks; stirrer in the center neck, and the outer necks containing condenser topped with nitrogen inlet/outlet, vacuum adapter, reagent addition tube, thermocouple, and stoppers.
• the flask was loaded with 7 L of toluene, 3.09 kg of 2.17 M iPrMgCI in Et 2 0, 250 mL of THF, and 1.03 kg of (Me 4 C s H)SiMe 2 NHtBu.
• the mixture was then heated, and the ether allowed to boil off into a trap cooled to -78 °C.
• R-1 and R-2 were slur ed in DME (the total volumes of the mixtures were approx. 5 L in R-1 and 12 L in R-2).
• the contents of R-1 were transferred to R-2 using a transfer tube connected to the bottom valve of the 10 L flask and one of the head openings in the 30 L flask.
• the remaining material in R-1 was washed over using additional DME.
• the mixture darkened quickly to a deep red/brown color.
• 1050 mL of 1 ,3- pentadiene and 2.60 kg of 2.03 M nBuMgCI in THF were added simultaneously.
• the maximum temperature reached in the flask during this addition was 53°C.
• the mixture was stirred for 2 hours, then approx.
• ARMEEN ® M2HT bis(hydrogenated-tallowalkyl)methylamine
• the flask was equipped with a 6 inch(15 cm) Vigreux column topped with a distillation apparatus and the mixture was heated (140°C external wall temperature). A mixture of ether and methylcyclohexane was distilled from the flask. The two-phase solution was now only slightly hazy. The mixture was allowed to cool to room temperature, and the contents were placed in a 4 L separatory funnel. The aqueous layer was removed and discarded, and the organic layer was washed twice with H 2 0, and the aqueous layers again discarded. The product solution was divided into two equal portions for the evaluation of two workup procedures. These H 2 0 saturated methylcyclohexane solutions were measured to contain 0.48 weight percent diethylether (Et 2 0).
• the solution (600 mL) was transferred into a 1 L flask, sparged thoroughly with nitrogen, and transferred into the drybox.
• the solution was passed through a column (1 inch (2.5 cm) diameter, 6 inch (15 cm) height) containing 13 times molecular sieves. This reduced the level of Et 2 0 from 0.48 weight percent to 0.28 weight percent.
• the material was then stirred over fresh 13 times sieves (20 g) for four hours.
• the Et 2 0 level was then measured to be 0.19 weight percent.
• the mixture was then stirred overnight, resulting in a further reduction in Et 2 0 level to approximately 40 ppm.
• the mixture was filtered using a funnel equipped with a glass frit having a pore size of 10 to 15 ⁇ m to give a clear solution (the molecular sieves were rinsed with additional dry methylcyclohexane).
• the concentration was measured by gravimetric analysis yielding a value of 16.7 weight percent.
• the polymer products of the Examples were produced in a solution polymerization process using a well-mixed recirculating loop reactor.
• the additive package was 1500 ppm calcium stearate, 600 ppm IrganoxTM 1076 hindered phenolic antioxidant, and 950 ppm PEPQ (tetrakis(2,4-di-t-butylphenyl)-4,4'- biphenylene diphosphonite) (available from Clariant Corporation).
• the additive package was 1450 ppm calcium stearate, 600 ppm IrganoxTM 1076, and 930 ppm PEPQ.
• the additive package was 640 ppm calcium stearate, 260 ppm IrganoxTM 1076, and 400 ppm PEPQ.
• ethylene and the hydrogen (as well as any ethylene and hydrogen which were recycled from the separator, were combined into one stream before being introduced into the diluent mixture, a mixture of C3-C-10 saturated hydrocarbons, for example, ISOPARTM-E (available from Exxon Chemical Company) and the comonomer 1-octene.
• a mixture of C3-C-10 saturated hydrocarbons for example, ISOPARTM-E (available from Exxon Chemical Company) and the comonomer 1-octene.
• the metal complex and cocatalysts were combined into a single stream and were also continuously injected into the reactor.
• the catalyst was as prepared in Catalyst Preparation One.
• the catalyst was as prepared in Catalyst Preparation Two.
• the catalyst was as prepared in Catalyst Preparation Three.
• the Primary and Secondary cocatalysts were as prepared in Cocatalyst Example One and Cocatalyst Example Two.
• the reactor pressure was held constant at about 450 to 475 psig (3.1 to 3.3 MPa).
• the reactor exit stream was introduced into a separator where the molten polymer was separated from the unreacted comonomer(s), unreacted ethylene, unreacted hydrogen, and diluent mixture stream, which was in turn recycled for combination with fresh comonomer, ethylene, hydrogen, and diluent, for introduction into the reactor.
• the molten polymer was subsequently strand chopped or pelletized, and, after being cooled in a water bath or pelletizer, the solid pellets were collected. Table One describes the polymerization conditions and the resultant polymer properties. Table 1. Run Conditions
• the following Table Two compares the melt index (l 2 ), density and melt flow ratio (l 10 /l 2 ) of the ethylene/octene copolymers produced using Catalyst Composition Three with the polymers of the invention prepared using Catalyst Compositions One and Two. Significantly higher molecular weight copolymers were produced using Catalyst Compositions One and Two than were produced using Catalyst Composition Three. For example, at a reactor temperature of 122°C, Catalyst One produced a polymer having an l 2 of 0.7 dg/min, while Catalyst Three produced a polymer having an l 2 of 116 dg/min copolymer.
• Catalysts One and Two are advantageous, in that they permit one to produce a copolymer of a specific molecular weight at a higher reactor temperature, thus reducing solution viscosity, reactor pressure drop, reactor fouling and improving the overall process economics.
• the copolymers produced using Catalysts One and Two had higher melt flow ratios. Such higher melt flow ratios are desirable, in that copolymers with higher melt flow ratios are easier to process, for instance, significantly lower pressures and amps are observed during the conversion of such copolymers into plastic parts.
• the polymerization was allowed to proceed for 10 minutes while feeding ethylene on demand to maintain a pressure of 445 psig (3.07 MPa). The amount of ethylene consumed during the reaction was monitored using a mass flow meter.
• the polymer solution was dumped from the reactor into a nitrogen-purged glass kettle containing 10 to 20 mL of isopropanol. An aliquot of the additive solution described below was added to this kettle and the solution stirred thoroughly (the amount of additive used was chosen based on the total ethylene consumed during the polymerization).
• the polymer solution was dumped into a tray, air dried overnight, then thoroughly dried in a vacuum oven for two days. The weights of the polymers were recorded and the efficiency calculated as grams of polymer per gram of transition metal.
• DSC Differential scanning calorimeter
• the copolymers of the invention prepared with Catalyst One had a Tm which is at least 10°C greater than that of the polymers of the Comparative Examples produced using Catalyst Three, which is expected to translate to an enhanced upper service temperature.
• Tm which is at least 10°C greater than that of the polymers of the Comparative Examples produced using Catalyst Three, which is expected to translate to an enhanced upper service temperature.
• the DSC thermograms of copolymers produced using Catalyst Two have a distinct bimodal character.
• the DSC thermogram for such polymer of Example 1 a corresponds to a DSC thermogram of a blend of two copolymers having densities of 0.855 and 0.897 g/cm 3 , respectively.
• the bimodal characteristic of the polymers of the invention prepared using Catalyst Two is further exemplified in a micrograph of polymer 2a produced by transmission electron microscopy (TEM), wherein one can clearly see the lamellae produced by the higher density copolymer fraction.
• TEM transmission electron microscopy
• well defined lamella were present in the polymer of Example 2a.
• These ribbon-like structures, with an aspect ratio of about 16 (1120A x 70A) appear relatively isolated in a matrix of granule-like fringed micelle structures, with an aspect ratio close to unity (70A).
• p r is the final density
• p., and p 2 are the densities of the first and second component fractions, respectively
• w., and w 2 are the weight fractions of the component fractions.
• the ATREF curves for Examples 1 b and 2a and for Comparative Example C-3a are set forth in Figure 7a. Because the overall densities of these copolymers were relatively low, most of the copolymer eluted with the purge, that is, the copolymer did not crystallize from the solvent (trichlorobenzene). In fact, 100 percent of the copolymer of Comparative Example C-3a eluted with the purge. The ATREF data showed that both Catalysts One and Two produced copolymers which were bimodal in short chain branching distribution.
• the bulk of the copolymer produced from these catalysts was a low density copolymer which eluted with the purge, but there was also a higher density copolymer which produced a peak in the ATREF chromatograms shown in Figure 7a. Comparing the copolymers of Catalyst One with that of Catalyst Two, Catalyst Two produced a smaller amount of the higher density copolymer. As shown in Table Four, the copolymer densities calculated from ATREF were similar to the DSC estimate.
• the copolymer of Example 2a had a density of 0.861 g/cm 3
• the ATREF peak corresponded to what one would typically see for a substantially linear ethylene/1-octene copolymer prepared using Catalyst Three and having a density of 0.895 g/cm 3 .
• the copolymer of Example 1a having a density of 0.871 g/cm 3 exhibited a DSC endotherm which corresponded to what one would typically see for a substantially linear ethylene/1-octene copolymer prepared using Catalyst Three having a density of 0.897 g/cm 3 .
• Example 1b had a density of 0.870 g/cm 3
• the ATREF peak corresponded to what one would typically see for a substantially linear ethylene/1- octene copolymer prepared using Catalyst Three and having a density of 0.886 g/cm 3 , which is consistent with the finding above that the copolymer of Example 1 b exhibited a DSC endotherm which corresponded to what one would typically see for a substantially linear ethylene/1-octene copolymer prepared using Catalyst Three having a density of 0.884 g/cm 3 .
• ATREF/DV may be further used to illustrate the fact that the copolymers of the invention are characterized as having a bimodal molecular weight distribution.
• the ATREF refractive index detector shows the unique short chain branching distribution of the copolymer of Example 45e produced by Catalyst Two.
• the ATREF differential viscometer detector (right hand verticle axis) shows that the copolymer comprises 92 weight percent of a lower density component which elutes at about 71 °C and has a weight average molecular weight of 417000 daltons, and about 8 weight percent of a higher density component which elutes at about 85°C and has a weight average molecular weight of 174000 daltons.
• the ATREF M w1 /M n2 ratio was 2.40, which was similar to the value determined by GPC deconvolution, shown in Table Six, i.e., 2.41.
• the following Figure 7d is a plot of the ATREF shape factor versus the average ATREF elution temperature. This data in this plot was generated from ATREF curves. Specifically, (i) the maximum ATREF peak height was measured, (ii) the width of the total ATREF peak at V_ the maximum peak height was measured, the ATREF shape factor was calculated, that is, the ratio (ii)/(i), and the average ATREF elution temperature was determined, that is, (minimum ATREF elution temp + maximum ATREF elution temp)/2.
• the polymer compositions of the invention are characterized as having a fraction which has a higher crystallinity than the other fraction.
• the presence of the higher crystallinity fraction translates to an enhancement in the upper service temperature of the polymer compositions of the invention, with respect to the comparative compositions prepared with Catalyst Three.
• dynamic mechanical data for the copolymers of Examples 1a and 2a, and for Comparative Example C-3c are compared in Figure 8.
• Figure 8a compares the storage modulus (G') and tan d (G"/G') as a function of temperature.
• the upper service temperature may be defined as the intersection of a line drawn across the upper non-melted plateau region and the descending melting transition region of the log G1 versus temperature plot, as indicated by the intersecting lines on Figure 8b.
• the upper service temperature of the copolymer of Example 1a was 75°C, which was 21 °C higher that of the Comparative Example C-3a which had an upper service temperature of 54°C.
• the upper service temperatures of the copolymer of Example 2a was 76°C, which was about 22°C higher than that of the copolymer of Comparative Example C- 3c, which was especially surprising in view of the fact that the copolymer of Example 2a had a lower density than that of copolymer C-3c.
• Figure 9a compares the upper service temperatures of the copolymers produced using Catalyst Two with copolymers produced using Catalyt Three, as a function of density. The curves in Figure 9a were simple polynomial fits through the data.
• the copolymers prepared with Catalyst Two which are used in Figure 9a include Example 2a, and examples prepared using a batch polymerization process set forth above utilizing Catalyst Two and the following reactor conditions:
• Figure 9b compares the increase in upper service temperature (UST) which can be achieved via blending copolymers prepared with Catalyst Three with the increase in UST achievable with the copolymers of the invention prepared with Catalyst Two.
• UST upper service temperature
• Figure 9b compares the increase in upper service temperature (UST) which can be achieved via blending copolymers prepared with Catalyst Three with the increase in UST achievable with the copolymers of the invention prepared with Catalyst Two.
• UST upper service temperature
• the copolymers of the invention exhibited unique behavior.
• a blend containing about 10 wt% of a higher density copolymer which corresponds to the relative proportion of the high density component in the copolymer produced by Catalyst Two, as illustrated in Figure 9a
• the copolymer produced using Catalyst Two exhibited a 24°C higher upper service temperature than the copolymer of the comparative blend.
• Comparative Example C-2a was produced in a batch reactor
• the copolymers of the Comparative Examples C-3a and C- 3b had GPC polydispersities (MJM n 's) of 2 16, while copolymers produced with Catalysts One and Two had polydispersities of 2 60 (Catalyst One) and 2 32 (Catalyst Two)
• l,(x) is the modified Bessel function of the first kind of order one, defined by
• ⁇ is related to the level of long chain branching via
• M is the average molecular weight of the repeating unit.
• the b individual terms of the expanded Bessel function represent the molecular weight distributions of the polymer chains carrying b long chain branches per molecule. Bamford and Tompa also provide equations to calculate the average number of branch points in a molecule as a function of chain length. See, for instance, CH. Bamford and H. Tompa "The Calculation of Molecular Weight Distributions from Kinetic Schemes" Trans. Faraday Soc, 50, 1097(1954).
• the "fit” MJM.'s provided a more consistent polydispersity estimate.
• the "fit” polydispersities for the copolymers of Comparative Examples C-3a and C-3b, Examples 1a - 1C , and Examples 2a - 2d, were 2.34, 2.50 and 2.71 , respectively.
• Comparative Example C-2a exhibited a polydispersity of 2.07, while Examples 2a - 2d exhibited a mean polydispersity of 2.32 ⁇ 0.15; similarly, "fit" polydispersities of 2.29 and 2.50 ⁇ 0.04, respectively, were observed for copolymers of Comparative Example C-2a and Examples 2a - 2d, respectively.
• the increased polydispersity correlates with the increase in melt flow ratio.
• the average l 10 /l 2 of the copolymers of Examples 2a - 2d was 13.3, while the copolymer of Comparative Example C-2a exhibited an l 10 /l 2 of 6.5.
• the higher MJM n and l 10 /l 2 suggest that the continuous process copolymers contained a higher concentration of long chain branches than the corresponding batch polymerized polymers. It is well known that long chain branching dramatically increases the shear thinning behavior of a copolymer.
• the copolymers of this invention were analyzed for indicia of long chain branching.
• rheological data were generated using a Rheometrics RMS-800 dynamic mechanical spectrometer with 25 mm diameter parallel plates in the oscillatory shear mode. Frequency sweeps were performed over the shear rate range of 0.1-100 rad/s at 15 percent strain in a nitrogen atmosphere. Rheological data are set forth in the following Table Seven.
• Copolymer C-2a was produced in a batch reactor.
• Figure 13 provides a plot of the log viscosity versus log frequency for the copolymers of in the invention and of the comparative examples as determined by RMS 800 rheometer in accordance with the procedure set forth above.
• the copolymer of Examples 2a exhibited enhanced shear thinning behavior over the copolymer of Comparative Example C-2a, both of which were produced with Catalyst Two.
• Figure 13 illustrates that the copolymer of Example 2a, prepared by a continuous process, was more elastic that the copolymer of Comparative Example C-2a, which was produced in a batch reactor, as indicated by the lower tan d value of the former.
• the copolymers produced with Catalyst One and Two were more resistant to melt fracture than the copolymer of Comparative Example C-2a, which was produced using Catalyst Three in a continuous reactor. Since shear rate is directly proportional to output (that is., Ib/hr or parts/hr), the copolymer of Example 2a, prepared with Catalyst Two, can be processed at higher rates relative to copolymer C-3c, prepared with Catalyst Three.
• Copolymers of the Examples and Comparative Examples were further tested for compression set in accordance with the following procedure.
• Compression set buttons were prepared for each sample by cutting 2.86 cm diameter (1.125-in.) disks from 1.52 mm thick compression molded plaques. Disks were stacked (total stack height approximately 1.37 cm (0.54-in.)) in a compression set mold (at room temperature) and the disks were fused at 176.7°C (350°F) and 10,000 psi (69 MPa) over 10 minutes. The buttons were removed from the mold, equilibrated at ASTM conditions for 24 hours, and the thickness of each button was measured with a micrometer.
• buttons were placed in a compression set clamp and compressed to 0.953 cm (0.375-in.) by tightening the nuts until the top platten made contact with the 0.953 cm spacers.
• the cold compression set clamp was placed in an oven at 70°C (158°F) for 24 hours.
• the buttons were removed from the compression set clamp and equilibrated at ASTM conditions for 24 hours prior to the measurement of button thickness. Compression set was expressed as the percentage of the deformation which was not recovered. Additional information on the compression set test can be found in ASTM D-395-89 method B.
• the compression set of copolymers of the invention produced with Catalyst One and Catalyst Two, and a comparative copolymer produced with Catalyst Three are summarized in Figure 14. Relative to the copolymer C-3c produced with Catalyst Three, the compression set at 70°C was lower for copolymers produced by Catalyst One and Catalyst Two, in spite of the similar crystallinity of the copolymers. Lower compression sets are desirable, in that, compression set represents the percentage of the deformation which was not recovered. Ideally, the compression set of perfect elastomers would be 0 percent, that is, the deformation would be completely recovered. The lower compression set of the copolymers of the invention produced via Catalyst One and Catalyst Two was attributed to the bimodal short chain branching distribution.
• Ethylene/propylene interpolymers are prepared in accordance with the following procedure utilizing the reactor conditions set forth in the following Table.
• the catalyst was prepared in a dry box by syringing together 5.0 micromol (0.005 M solution) of the metal complex (isopropylamido)dimethyl( ⁇ 5-2, 3,4,6- tetramethylindenyl)silanetitanium (IV) dimethyl, 5 micromol (0.0075 M solution) of the cocatalyst di(hydrogenated-tallowalkyl)methylammonium tetrakis(pentafluorophenyl)borate, 50.0 micromol (0.050 M solution) of the scavenger (diisopropylamido)diethylaluminum, and additional Isopar E * to give a total volume of 18 mL.
• the metal complex isopropylamido)dimethyl( ⁇ 5-2, 3,4,6- tetramethylindenyl)silanetitanium (IV) dimethyl
• the catalyst solution was then transferred via syringe to a catalyst addition loop and injected into the reactor over approximately 4 minutes using a flow of high pressure solvent.
• the polymerization was allowed to proceed for 10 minutes while feeding ethylene on demand to maintain a pressure of 460 psig (3.2 MPa).
• the amount of ethylene consumed during the reaction was monitored using a mass flow meter.
• the polymer solution was then poured from the reactor into a nitrogen-purged glass kettle and stabilizer (IrganoxTM 1076) were added and mixed well with the solution.
• the polymer solution was poured into a tray, air dried overnight, then thoroughly dried in a vacuum oven for one day.
• the yield of polymer was 37.0 g, and the catalyst efficiency calculated as grams of polymer per gram of transition metal was 0.15 million.
• the obtained terpolymer had a composition of 54.7 wt percent ethylene, 42.7 wt percent propylene, 2.6 wt percent ethylidene norbornene.
• the molecular weight was 147,200 with a molecular weight distribution of 2.18.
• the elastomer had a measured glass transition temperature of -53.9°C and was 0.9 percent crystalline.
• sixteen ethylene/ propylene copolymers are prepared using the ingredient amounts shown in Table below.
• the polymer physical properties are shown in the subsequent table.
• the catalyst of Examples 1a - 1e is (cyclohexylamido)dimethyl( ⁇ 5-2, 3,4,6- tetramethylindenyl)silanetitanium (IV) dimethyl.
• the catalyst of Examples 2a - 2f is (isopropylamido)dimethyl( ⁇ 5-2,3,4,6-tetramethylindenyl)silanetitanium (IV) dimethyl.
• the catalyst of the comparative examples is is (tetramethylcyclopentadienyl)dimethyl(t- butylamido)silanetitanium 1 ,3-pentadiene.
• the cocatalyst of all Examples is di(hydrogenated- tallowaikyl)methylammonium tetrakis(pentafluorophenyl)borate.
• the scavenger of all Examples is a derivative of diisobutyl aluminum.
• An ethylene/propylene/diene interpolymer is prepared using the general polymerization procedure set forth above using the reactor conditions set forth below.
• the resultant polymer had 54.7 weight percent ethylene, 42.7 weight percent propylene, 2.6 weight percent ENB.
• GPC-dv results indicate that the polymer had an Mw of 147200, an Mn of 67500, an M w /M n of 2.18.
• the examples show that semi-crystalline EP and EPDM interpolymers with ethylene content greater than 45 weight percent (EP 2f and EP 1e) display the DSC characteristics observed for other copolymers.
• amorphous materials with less than 45 weight percent ethylene prepared with the catalysts of this invention have lower Tg and higher molecular weight than polymers prepared under the same conditions with (tetramethylcyclopentadienyl)dimethyl(t-butylamido)silanetitanium 1,3-pentadiene.
• Example B Preparation of (2,3-dimethylindenyl)dimethyl(cvclo-dodecylamido)silanetitanium dimethyl (2,3-dimethylindenyl)dimethyl(cyclododecylamido)silane T1CI2 (0.200 g, 0.000400 moles) was stirred in diethylether (50 mL) as methylMgl (0.00084 moles, 0.28 mL 3.0 M solution in diethylether) was added dropwise. This mixture was then allowed to stir for 30 minutes. After the reaction period the volatiles were removed and the residue extracted and filtered using hexane. Removal of the volatiles followed by a repeat of the filtration again using hexane resulted in the isolation of the desired product as an orange crystalline solid after the removal of the hexane (0.134 g, 73.2 percent).
• a two-liter Parr reactor was charged with 740 g of mixed alkanes solvent (lsoparTM-E) and 118 g of 1-octene comonomer. Hydrogen was added as a molecular weight control agent by differential pressure expansion from an ⁇ 75 ml addition tank at 25 psi (2070 Kpa). The reactor was heated to the polymerization temperature of 140°C and saturated with ethylene at 500 psig (3.4 Mpa). 2.0 mmol each of catalyst and cocatalyst at 0.005M solutions in toluene were premixed in the drybox. After the desired premix time, the solution was transferred to a catalyst addition tank and injected into the reactor. The polymerization conditions were maintained for 15 minutes with ethylene on demand.
• lsoparTM-E mixed alkanes solvent
• 1-octene comonomer 1-octene comonomer. Hydrogen was added as a molecular weight control agent by differential pressure expansion from an ⁇ 75
• the resulting solution was removed from the reactor, and a hindered phenol anti-oxidant (irganoxTM 1010 from Ciba Geigy Corp.) was added to the resulting solution.
• a hindered phenol anti-oxidant irganoxTM 1010 from Ciba Geigy Corp.
• Polymers formed were dried in a vacuum oven set at 120°C for about 20 hours.
• Dimethylsilyl(2,3,4,6-tetramethylindenyl)CI (22.29 grams, 84.17 mmol) was stirred in THF as i-PrNH 2 (28.68 mL, 336.7 mmol) was added. The mixture was stirred for 16 hours. The volatiles were removed under reduced pressure. The residue was extracted with hexane and filtered through a diatomaceous earth filter aid on a 10 to 15 mm glass frit. The hexane was removed under reduced pressure to afford the product as a yellow oil. Yield; 17.23 grams, 71 percent.
• the reaction was filtered through a diatomaceous earth filter aid (Celite TM) on a 10-15 mm glass frit.
• the salts and filter aid were washed with 50 mL of pentane. The solvent was removed under reduced pressure to afford a red/brown powder. Yield; 300 mg, 45 percent.
• the catalyst was prepared in a drybox by syringing together 5.0 mmol (1.0 mL, .005 M) of the metal complex, 15.0 mmol (1.0 mL, .015 M) of cocatalyst, trispentafluorophenylborane (TPFPB), and 50.0 mmol (1.0 mL, .05 M) of scavenger, modified methylaluminoxane (from Akzo-Nobel), with additional Isopar E TM to give a total volume of 17 mL.
• the catalyst solution was then transferred by syringe to a catalyst addition loop and injected into the reactor over approximately 4 minutes using a flow of high pressure solvent.
• the polymerization was allowed to proceed for 10 minutes while feeding ethylene on demand to maintain a pressure of 445 psig (4.5 Mpa).
• the polymer solution was then poured from the reactor into a nitrogen-purged glass kettle containing approximately 15 mL of isopropanol.
• a 20 mL aliquot of a stabilizer solution prepared by dissolving 6.66 g of Irgaphos TM 168 and 3.33 g of Irganox TM 1010 in 500 mL of toluene was added.
• the polymer solution was poured into a tray, air dried overnight, then thoroughly dried in a vacuum oven for two days.
• Chlorodimethyl(1 ,5,6,7-tetrahydro-2-methyl-s-indacen-1-yl) silane (5.67 g, 0.0216 moles) was stirred in hexane (50 mL) as NEt 3 (2.18 g, 0.0216 moles) and cyclohexylamine (2.13 g, 0.0216 moles) were added. This mixture was allowed to stir 16 hours. After the reaction period the mixture was filtered and the volatiles removed resulting in the isolation of the desired product as a yellow oil (6.62 g, 94.3 percent).
• N-(cyclohexyl)-1 ,1-dimethyl-1-(1 ,5,6,7-tetrahydro-2-methyl-s-indacen-1-yl)silanamine (6.67 g, 0.02048 moles) was stirred in hexane (100 mL) as nBuLi (0.04302 moles, 21.51 mL of 2.0 M solution in cyclohexane) was added slowly. This mixture was then allowed to stir 16 hours. After the reaction period the desired product was isolated as a solid which was used without further purification or analysis (7.23 g, product still contained residual hexane).
• Chlorodimethyl(1 ,5,6,7-tetrahydro-2,3-dimethyl-s-indacen-1-yl)silane (5.00 g, 0.01806 moles) was stirred in hexane (80 mL) as NEt 3 (3.29 g, 0.03251 moles) and t-butylamine (1.81 g, 0.01824 moles) were added. This mixture was allowed to stir 16 hours. After the reaction period the mixture was filtered and the volatiles removed resulting in the isolation of the desired product as a yellow oil (5.55 g, 90.9 percent).
• N-(cyclohexyl)-1 ,1-dimethyl-1-(1 ,5,6J-tetrahydro-2,3-dimethyl-s-indacen-1- yl)silanamine (5.30 g, 0.01570 moles) was stirred in hexane (75 mL) as n-BuLi (0.03454 moles, 13.8 mL of 2.5 M solution in hexane) was added slowly. This mixture was then allowed to stir for 72 hours. After the reaction period the hexane was decanted away and the volatiles were removed resulting in the isolation of the desired product as an orange glassy solid which was used without further purification or analysis (5.56 g, 99.9 percent).
• Example J After the reaction period the volatiles were removed and the residue extracted and filtered using toluene. Removal of the toluene resulted in the isolation of a dark residue. This residue was then slurried in hexane and cooled in a refrigerator for 72 hours. The desired product was then isolated via filtration as a solid (0.259 g, 43.8 percent).
• Chlorodimethyl(1 ,5,6J-tetrahydro-3-phenyl-s-indacen-1-yl) silane (3.8523 g, 0.01182 moles) was stirred in hexane (100 mL) as NEt 3 (1.5136 g, 0.01496 moles) and cyclohexylamine (1.2107 g, 0.01221 moles) were added. This mixture was allowed to stir for 24 hours. After the reaction period the mixture was filtered and the volatiles removed resulting in the isolation of the desired product as a yellow oil (4.3313 g, 94.5 percent).
• N-(cyclohexyl)-1 ,1-dimethyl-1-(1,5,6,7-tetrahydro-3-phenyl-s-indacen-1-yl)silanamine (4.3313 g, 0.01117 moles) was stirred in hexane (100 mL) as nBuLi (0.024 moles, 12.00 mL of 2.0 M solution in cyclohexane) was added slowly. This mixture was then allowed to stir 16 hours during which time a sticky precipitate formed. The volatiles were then removed and the resulting pale yellow solid slurried in cold hexane.
• a stirred 3.8 liter reactor was charged with 1440 g of Isopar-ETM mixed alkanes solvent (available from Exxon Chemicals Inc.) and 126 g of 1 -octene comonomer. Hydrogen was added as a molecular weight control agent by differential pressure expansion from a 75 mL addition tank at 25 psid (2070 kPa). The reactor was heated to the polymerization temperature of 130 °C and saturated with ethylene at 450 psig (3.1 MPa).

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