EP0880549A2 - Catalyst system and components - Google Patents

Abstract

Provided are organosilane compounds having structure (I), wherein R1 and R2 are the same or different and are selected from the group consisting of alkyl radicals, cycloalkyl radicals, and polynuclear radicals, said polynuclear radicals having nine or more carbon atoms, wherein at least one of R1 or R2 is a polynuclear radical of nine or more carbon atoms, with the proviso that where either R1 or R2 is indenyl or fluorenyl, the other of R1 or R2 is a substituted or unsubstituted bridged cyclic aliphatic radical or is a polynuclear aromatic radical of ten or more carbon atoms and wherein Ry and Rz are the same or different and each Ry and Rz are selected from alkyl radicals having one or two carbon atoms. In a preferred variation, R1 is a polynuclear aromatic radical having ten or more carbon atoms, and R2, Ry and Rz are the same or different and each R2, Ry and Rz are selected from alkyl radicals having one or two carbon atoms. Also provided are organosilanes having structure (II), wherein R1 is a polynuclear aromatic radical having ten or more carbon atoms, and wherein Rx, Ry et Rz are the same or different and each Rx, Ry and Rz are selected from alkyl radicals having one or two carbon atoms. Such organosilanes are provided for use as modifiers for olefin polymerization catalyst systems. Polymers of propylene are provided which have a crystallinity melt temperature exceeding 164 °C, percent crystallinities exceeding 55 % as measured by DSC (ΔHf=212J/g pour 100 %) and a molecular weight distribution of from 5 to 10.

Description

CATALYST SYSTEM AND COMPONENTS

FIELD OF THE INVENTION

In one aspect, this invention relates to organosilane modifiers for catalyst systems and processes to make such modifiers. In another aspect, this invention relates to catalyst systems and processes for polymerization of olefins using organosilane modifiers external to supported catalyst components. In one specific aspect, this invention relates to bulky organosilane modifiers which are useful to produce polypropylene having both high crystallinity and broad molecular weight distribution.

BACKGROUND OF THE INVENTION Olefin polymerization catalyst systems comprising (i) a catalyst component of titanium, magnesium, and an "internal modifier" or "first electron donor"; (ii) a cocatalyst or "activator" such as an alkyl aluminum compound; and (iii) an "external modifier" or "second electron donor" are very well known in the art. A variety of diesters, esters, amines, and silanes have been used as external modifiers, and in particular, certain alkoxysilanes have been used as external electron donors, including specific aromatic and aliphatic alkoxysilanes.

For example, with catalyst systems used in the polymerization of propylene, it is known that external donors can modify the performance of the catalyst system and can increase crystallinity of the resulting polymer. While it is known that choice of external donor used in the production of isotactic polypropylene can impact polymer crystallinity, it has not, however, been possible to predict with certainty donor performance or product crystallinity or any other polymer characteristics affected by use of the donor.

Even though major research efforts have focused on external donors, the mechanism by which external donors modify catalysts remains unclear. External donors continue to be studied in a search for donor structures that will enable catalyst systems to produce "highest crystallinity" polymers. There is, for example, still a need for highly crystalline commercial polypropylene, particularly in durables applications such as automotive and appliance parts, and there is a corresponding need to increase polypropylene's "stiffness", typically as measured by flexural modulus.

Although certain organosilanes used as external donors, such as diisopropyldimethoxysilane, diisobutyldimethoxysilane, di-t-butyldimethoxy-silane, and dicyclopentyldimethoxysilane, enable production of polypropylene with increased crystallinity, such donors unfortunately also produce polymer with narrow molecular weight distributions ("MWD") and narrow ranges of melt flow rate ("MFR"). For example, U.S. Patent 5,218,052 discusses polymer data derived from use of diisopropyldimethoxysilane, diisobutyldimethoxysilane and di-t- butyldimethoxysilane as external donors in a two step polymerization process seeking to make a reactor blend of high and low molecular weight polymers. The reactor blend is to have a synthetic broad molecular weight distribution but such blended polymer has low melting points and low melt flow rates. U.S. Patent 5,218,052 treats silane donors generically and cites as donors, diisopropyldimethoxysilane, diisobutyldimethoxysilane, di-t-butyldimethoxy-silane, t-butyldimethoxysilane, diisopentyldimethoxysilane, di-t-pentyldimethoxy-silane, dineopentyldimethoxysilane, neopentyldimethoxysilane, isobutylisopropyl- dimethoxysilane, isobutyl-t-butyldimethoxysilane, isopropyl-t-butyldimethoxy- silane and di-p-tolyldimethoxysilane. U.S. Patent 5,218,052 fails to recognize the advantage of certain classes or types of silane donors in making highly crystalline polypropylene in a single step process.

Thus, there continues to be a need for catalyst systems and donors which can produce polypropylene with high crystallinity, a high flexural modulus and high melt flow rates. There is a need for commercial polypropylenes having high crystallinity melts of greater than 164°C with a percent crystallinity of 55% or more. These plastics are needed for applications in automotive structural components, food packaging, and other applications where high flexural modulus and good heat resistance are required.

A need continues in molding applications for polymers with broad melt flow rate ranges, with a high melt flow rate over 100, to enable faster molding device cycle times. Where the molecular weight distribution of a polymer is broadened especially at the high molecular weight end, the orientation of the polymer in a surface layer of an injection molded article causes an apparent higher crystallinity of the polypropylene due to the thickness or depth of oriented polymer at the surface. SUMMARY OF THE INVENTION

We have discovered that certain organosilane donors having a bulky structure, preferably those comprising a polynuclear group of nine or more carbons, enhance the performance of olefin polymerization catalyst systems. We have surprisingly found that certain silane donors with bulky substituents produce polymers with improved desirable polymer properties while other bulky silane donors do not. We have found that bulky indenyl, fluorenyl and Co. and C]o and higher polynuclear aromatic radicals are effective as Si donor constituent groups when the remaining Si donor constituents have only one or two carbons, such as methyl or ethyl radicals. The silane donors of this invention are thus a unique class of silane donors, being very bulky at a portion of the zone around the Si atom and having essentially very small bulk at the remaining portion of the zone around the Si atom.

We have found that donors of this invention produce polypropylenes which have high crystallinity and which exhibit unique molecular weight distribution and melt flow rate characteristics. While prior art donors that produce high crystallinity polymer unfortunately produce polymer with narrow molecular weight distributions and narrow MFR ranges, we have produced novel silane donors that give high crystallinity polypropylene as well as broad molecular weight distribution with wide melt flow rate ranges. These donors of our invention also produce polypropylene with excellent flex modulus.

We have discovered an external electron donor which is useful with, or as a part of, heterogeneous catalyst systems to produce highly crystalline isotactic polypropylene having crystalline melting points exceeding 164°C. We have also produced polypropylene having exceptionally high percent crystallinity and melting temperature. DESCRIPTION OF PREFERRED EMBODIMENTS

In one embodiment of this invention, we provide silane compounds having the following Structure I:

^1 Ry

Si

/ \ R₂ ORz

Structure I wherein R\ and R2 are the same or different and are selected from the group consisting of alkyl radicals, cycloalkyi radicals, and polynuclear radicals, said polynuclear radicals having nine or more carbon atoms, wherein at least one of Rj or R2 is a polynuclear radical of nine or more carbon atoms, with the proviso that where either R] or R2 is indenyl or fluorenyl, the other of Rj or R2 is a substituted or unsubstituted bridged cyclic aliphatic radical or is a polynuclear aromatic radical of ten or more carbon atoms, and wherein Ry and Rz are the same or different and each Ry and Rz are selected from alkyl radicals having one or two carbon atoms

In a preferred variation of this embodiment of this invention, we provide silane compounds of Structure I wherein Ri is a polynuclear aromatic radical having ten or more carbon atoms, and wherein R2, Ry and Rz are the same or different and each R2, Ry and Rz are selected from alkyl radicals having one or two carbon atoms.

- 5 -

In another embodiment of this invention, we provide silane compounds having the following Structure II:

R

Structure II wherein Rj is a polynuclear aromatic radical having ten or more carbon atoms, and wherein Rx, Ry and Rz are the same or different and each

Rx, Ry and Rz are selected from alkyl radicals having one or two carbon atoms.

As used in the Specification and Claims, the term "polynuclear radical" means fused ring hydrocarbons sharing at least one pair of carbon atoms. Furthermore, as used in the Specification and Claims, the term "polynuclear radical" may also include "indenyl" radicals means C9H7" radical from indene, and other radicals having indenyl structures such as "fluorenyl" C13H9" radical derived from fluorene and fluoranthenyl C19H13" radical derived from fluoranthene. Such indenyl containing structures include all of the various indenyl isomers. As used herein, the term "alkyl" means branched and straight chain hydrocarbon radicals, having from one up to 20 carbon atoms, which may be substituted or unsubstituted with one or more radicals containing other than hydrogen and carbon such as those selected from halo, amino, nitro, and other radicals. The term

"cycloalkyi" as used herein means an alicyclic hydrocarbon radical having from seven up to 20 carbon atoms, which may be substituted or unsubstituted with one or more radicals containing other than hydrogen and carbon such as those selected from halo, amino, nitro, and other radicals.

In preferred variations of this embodiment of this invention, when R] or R2 are polynuclear radicals, preferred polynuclear radicals include but are not limited to indenyl, fluorenyl, fluoranthenyl and preferred polynuclear aromatic radicals include, but are not limited to, naphthyl; naphthylenyl, naphthylidenyl, naphthindenyl, alkyl- and dialkyl- naphthyls such as methylnaphthyl, dimethylnaphthyl, ethylnaphthyl , and propylnaphthyl; phenylnaphthyl; anthracyl, phenanthryl; l-methyl-7-isopropylphenanthyl; halonaphthyls such as bromo- and chloro- naphthyls; nitronaphthyls, and amine substituted naphthyls. These include without limitation polynuclear aromatic groups derived, directly or indirectly, from naphthalene; alkylnaphthalenes such as 1-methylnaphthalene, 2-methylnaphthalene, ethyl naphthalene, and propylnaphthalene; phenylnaphthalene; anthracene; phenanthrene; l-methyl-7-isopropylphenanthalene; halonaphthalenes such as 1- bromonaphthalene, 2-bromonaphthalene, 1 -chloronaphthalene, and 2- chloronaphthalene as well as fluoranthene; nitronaphthyls such as 1- nitronaphthalene, 2-nitronaphthalene, and amine substituted naphthylenes such as 1-naphthylamine and 2-naphthylamine. In one preferred variation of Structure I, if either Ri or R2 has ten carbon atoms, then such K\ or R2 having ten carbon atoms preferably has six or fewer hydrogen atoms or is substituted.

In another preferred variation of the embodiment of Structure I, R\ and R2 are different and one of R] or R2 is polynuclear radical of nine or more carbons and the other of R\ and R2 has 7 or more carbons and is selected from the group consisting of, saturated and unsaturated and substituted and unsubstituted, straight chain aliphatics, branched aliphatics, and unbridged and bridged cyclic aliphatics. In a still more preferred variation of Structure I, K\ and R2 are different and one ofRi or R2 is selected from indenyl, fluorenyl, or a polynuclear aromatic of ten or more carbons and the other of Rj and R2 is a substituted or unsubstituted bridged cyclic aliphatic group. Preferred bridged cyclic aliphatic groups include without limitation norbornyl and alkyl substituted norbornyls such as methylnorbornyl, ethylnorbornyl, and propylnorbornyl.

In one variation of this embodiment, we provide organosilane norbornylindenyldimethoxysilane compounds of the formula

(C7H1 j)(C9Hy)Si(OCH3)2 Preferred norbornylindenyldimethoxysilane compounds include those having a structure of

and isomers thereof

In another variation of this embodiment, we provide organosilane dinaphthyldimethoxysilane compounds of the formula (CioHy)2Si(OCH3)2 Preferred dinaphthyldimethoxysilane compounds include those having a structure of

and isomers thereof

It is understood by one skilled in the art that one or more isomers of the specific structures shown are possible, and that mixtures of isomers may be useful in the practice of the embodiments of this invention

In another embodiment of this invention, we provide a method to prepare norbornylindenyldimethoxysilane comprising (a) reacting indene with methyllithium in a diluent to form indenyllithium, (b) reacting indenyllithium with norbornyltrichlorosilane in a solvent to form LiCl and norbornylindenyldichlorosilane, (c) separating said LiCl from said norbornylin- denyldichlorosilane, (d) reacting norbornylindenyldichlorosilane with methyl alcohol and pyridine in presence of a first solvent; (e) separating a HCl'pyridine complex from norbornyl-indenyldimethoxysilane, and (f) recovering said norbornyl-indenyldimethoxysilane The above method can be used to make various isomers of said norbornylindenyldimethoxysilane. In another embodiment of this invention, we provide a method to prepare bis-(naphthyl)dimethoxysilane comprising (a) reacting bromonaphthalene with magnesium to form a magnesium salt CioH7MgBr^«(CH3CH2)2O)x, where x > 0; (b) reacting said salt with SiCl4 in the presence of a first solvent at an elevated temperature to form a heated solution containing bis-(naphthyl)silicondichloride; (c) cooling said heated solution to crystallize at least a portion of said bis-(naphthyl)silicondichloride; (d) removing said first solvent; (e) reacting bis-(naphthyl)silicondichloride with pyridine and methanol in the presence of a second solvent to form bis-(naphthyl) dimethoxysilane; and (f) recovering said bis- (naphthyl)dimethoxysilane. The above method can be used to make isomers of bis- (naphthyl)dimethoxysilane.

Those skilled in the art using the above described procedures can prepare preferred compounds of the present invention according to one of the following preferred procedures, Procedure A or Procedure B: Procedure A:

R]M + R₂SiX₃ → R!R₂SiX2 + MX R!R₂SiX₂ + RyOH + RzOH → R^Si (ORy)(ORz) wherein Rj and R2 are as defined above, and X is a halogen such as chlorine or bromine and M is a reactive metal for Procedure A such as lithium, and Ry and Rz can be the same or different and are as defined above. Procedure B:

RjX + M → RiMX

(R!)₂SiX₂+ RyOH+ RzOH) → (Rι )₂Si(ORy)(ORz) wherein R\ is as defined above, X is a halogen such as bromine or chlorine and M is a reactive metal for Procedure B such as magnesium, and Ry and Rz can be the same or different and are as defined above.

In still another embodiment of this invention, an olefin polymerization catalyst system comprising (a) a catalyst component comprising titanium, magnesium, and a first electron donor; (b) an organometallic cocatalyst; and, (c) one or more organosilanes having Structure I or having Structure II. Preferred organosilanes include 1 -naphthyl trimethoxysilane, 1 -naphthyltriethoxysilane, and indenyltriethoxysilane. Preferably, the organosilane is bis-(l -naphthyl) dimethoxysilane or is norbomylindenyldimethoxysilane. More preferably, the catalyst system further comprises hydrogen as a chain transfer agent.

In another embodiment of this invention, a process for polymerizing one or more alpha-olefins comprises contacting, at polymerization conditions, one or more alpha-olefins with a catalyst system comprising (a) a catalyst component comprising titanium, magnesium, and a first electron donor; (b) an organometallic cocatalyst; and, (c) one or more organosilanes having Structure I or having Structure π.

Preferred alpha-olefins in the various embodiments of this invention are C3 to CIO alpha-olefins such as propylene, butene- 1, pentene-1, 4-methyl-l-pentene, hexene, octene, and decene.

In another embodiment of this invention, a process for polymerizing ethylene and one or more alpha-olefins comprising contacting, at polymerization conditions, ethylene and one or more alpha-olefins with a catalyst system comprising (a) a catalyst component comprising titanium, magnesium, and a first electron donor; (b) an organometallic cocatalyst; and, (c) one or more organosilanes having Structure I or having Structure II.

In another embodiment of this invention, a process for polymerizing ethylene comprising contacting, at polymerization conditions, ethylene with a catalyst system comprising (a) a catalyst component comprising titanium, magnesium, and a first electron donor; (b) an organometallic cocatalyst; and, (c) one or more organosilanes having Structure I or having Structure II. In preferred variations of the polymerization processes of this invention, the polymerization is conducted in the presence of hydrogen. Even more preferably, the polymerization is conducted in the presence of a hydrogenation catalyst. Preferably the hydrogenation catalyst is used in a manner such that the hydrogenation catalyst removes hydrogen or consumes hydrogen. Preferred hydrogenation agents are metallocenes where the metal is selected from the group consisting of titanium, zirconium and hafnium. Preferred metallocenes include alkyl organocyclic metal halides, where the organocyclic has two or more conjugated double bonds. A preferred titanocene is bis(n-butylcyclopentadiene) titanium dichloride.

In another embodiment of this invention, a homopolymer of propylene is provided having a crystallinity melt temperature exceeding 164°C, a percent crystallinities exceeding 55% as measured by differential scanning calorimetry "DSC", (where ΔHf=212J/g for 100% crystalline isotactic polypropylene) and a molecular weight distribution of from 5 to 10 by rheometric measurement analysis ("RMA"). In one preferred variation of this embodiment, molecular weight distribution (MWD) is from 6 to 9. Depending on donor selection, the MWD can preferably be from 6 to 7, and still more preferably can be from 8 to 9.

In one embodiment, a true homopolymer of propylene having a crystallinity melt temperature exceeding 164°C, a percent crystallinity exceeding 55%, and a molecular weight distribution of from 5 to 10 is provided. As used in the Specification and Claims, the term "true homopolymer" means a polymer prepared at polymerization conditions of uniform or substantially constant polymerization temperature, catalyst concentration, hydrogen concentration, and propylene (excess) concentration. By "substantially constant" is meant within normal process operating variability for target operating conditions, which by way of example and not limitation may be 5°C± or more for polymerization temperature and 100 kPa± or more for hydrogen pressure. One of the most preferred polymerization processes of this invention is a "single stage" process wherein the term "single stage" means one or more reactors operating at balanced conditions or operating at substantially similar conditions which are maintained substantially constant, except preferably for differing hydrogen concentrations or preferably differing concentrations of hydrogenation catalyst. Balanced conditions and balanced reactors differ from unbalanced conditions and unbalanced reactors, at least in part, in that unbalanced reactors have two reactors or reactor stages operating at substantially differing hydrogen concentration or other conditions and producing differing polymers.

The catalyst modifiers of this invention are useful with olefin polymerization catalyst systems for polymerization of ethylene or alpha-olefins as well as polymerization of mixtures of one or more alpha-olefins with ethylene. The modifiers are particularly effective with conventional olefin polymerization catalyst systems for polymerization of propylene or mixtures propylene and ethylene. Conventional olefin polymerization catalyst systems typically comprise (a) a catalyst component of titanium, magnesium and a first, internal electron donor, (b) a cocatalyst component or "activator", usually a Group II or III metal alkyl such as an alkyl aluminum and (c) a second, external electron donor.

Various catalyst components of titanium, magnesium, a first electron donor are commercially available, and this invention is not limited to a specific catalyst component. Typically, a catalyst component is a solid component, having a titanium constituent supported on a compound of magnesium and combined with a first electron donor compound. Catalyst components generally comprise from 1 to 10 wt% titanium, from 5 to 35 wt% magnesium, and from 40 to 70 wt% halogen based on 100 wt% of titanium, magnesium and halogen, with internal electron donor being present in the range from 0.03 to 0.6 grams internal modifier per gram of magnesium compound. Various methods to produce such catalyst components are well known.

For example, such catalyst components are typically prepared, in an inert atmosphere, by reacting a titanium halide with a compound of magnesium in the presence of the first electron donor.

Titanium compounds useful in preparing such catalyst component may be one or more of titanium halides and haloalcoholates. Examples of such compounds include titanium tetrahalides, preferably as TiCLj and TiBr.}, and Ti(OCH3)Cl3, - 12 -

Ti(OC₂H₅)Cl3, Ti(OC₄H₉)Cl₃₎ Ti(OC₆H₅₎Cl₃₎ Ti(OC₆H₁₃)Br₃,

Ti(OC₈H₁₇)Cl₃, Ti(OCH₃)₂Br₂, Ti(OC₂H5)₂Cl2, Ti(OC₆H₁₃)₂Cl₂₎ Ti(OC₈H₁₇)₂Br₂, Ti(OCH₃)₃Br, Ti(OC₂H₅)₃Cl, Ti(OC₄H₉)₃Cl,

Ti(OC₆H₁₃)₃Br, and Ti(OC₈H_{] 7})₃Cl. Magnesium compounds useful in preparing such catalyst component may be one or more of a magnesium alcoholate; a magnesium alkyl; a magnesium halide; or a reaction product of a magnesium halide with an alcohol or an organic acid ester or with an organometallic compound of metals of Groups I-III.

Electron donors useful as internal donors in preparing such catalyst component may be one or more organic compounds containing one or more of oxygen, nitrogen, sulfur, and phosphorus. Such compounds include organic acids, organic acid esters, alcohols, ethers, aldehydes, ketones, amines and other compounds. The Ci -Cg alkyl benzoates, C] and C2 halobenzoates, and dialkyl phthalates are well known internal donors. To remove impurities such as unreacted starting materials, the catalyst component is typically "washed" with an inert liquid and "washed" again with one or more Lewis acids such TiCl4, SiC.4, SnCl4, BCI3, AlBr3, or others.

A common commercial catalyst component comprises TiCl4 supported onto a MgCl2 surface with a diester as internal donor being co-milled or otherwise combined with the TiCl4 and MgCl2 in the steps of producing the supported titanium. The amount of catalyst component to be employed varies depending on choice of polymerization technique, reactor size, monomer to be polymerized, and other factors known to persons of skill in the art, and can be determined on the basis of the examples appearing hereinafter. Typically, catalyst components are used in an amount from 2 to 3 x 10"⁵ grams of catalyst to gram of polymer produced; however, catalyst usage varies with activity of the catalyst.

Various cocatalysts or "activators" are also well known and this invention is not limited to specific cocatalysts. Commonly used cocatalysts include Group II and IIIA metal alkyls such as A1(CH₃)₃, A1(C₂H₅)₃, A1(C₃H₇)₃, A1(C₄H₉)3, Mg(CH₃)₂, Mg(C₂H₅)₂, Mg(C₂H5)(C4H9), Mg(C₄H₉)₂, Zn(CH₃)₂, Zn(C H5)2, and Zn(C4H9)2 and others. Commercial cocatalyts also include metal alkyls having one or more halogen or hydride groups, and mixtures thereof, such as ethylaluminum dichloride, diethylaluminum chloride, ethylaluminum sesquichloride, diisobutylaluminum hydride and others. Typically, cocatalyst is employed in an amount so that the atomic ratio of cocatalyst component metal atoms to catalyst metal is in the range of 1 to 100. Where aluminum is cocatalyst metal and titanium is the catalyst metal, a preferred ratio of Al metal atoms to Ti metal atoms is in the range of 5 to 50. Triethylaluminum is a prefered activator.

The catalyst component may be combined with the cocatalyst and external donor in one step in the polymerization reactor. Alternatively, the catalyst component, the cocatalyst and external donor may be contacted in a first prepolymerization step with an olefin, preferably in the presence of an inert compound as inactive diluent, to form a polymer coated catalyst particle which is then fed to the polymerization reactor.

The catalyst system of this invention may include, in addition to one or more donors of this invention, one or more additional other external silane donors such as dinorbornyldimethoxysilane; tetramethoxysilane; dicyclopentyl- dimethoxysilane; methylcyclohexyldimethoxysilane; diphenyldimethoxysilane; tetraethoxysilane; and cyclopentyl-t-butoxydimethoxysilane and such other donors as organic acids, organic acid esters, alcohols, ethers, aldehydes, ketones, amines and other compounds. The Cj-Cό alkyl benzoates, C] and C2 halobenzoates, and dialkyl phthalates.

Where silanes are used as external modifiers or donors, the silane compound donor is preferably added so that the molar ratio of cocatalyst metal to silane is 1 to 50. Preferred catalyst systems of this invention have external silane donors of this invention present in an amount ranging from 0.05 to 1.0 moles of silane donor per moles of cocatalyst metal.

One preferred catalyst system of this invention will include the above described catalyst components in the following amounts, each amount is based on one gram of magnesium halide: (i) from 0.08 to 0.12 grams titanium tetrahalide, (ii) from 0.06 to 0.24 grams internal modifier, (iii) from 2 to 75 grams cocatalyst activator aluminum, (iv) from 0 14 to 28 grams external modifier and (v) one gram of magnesium halide

Polymerization conditions such as selection of solvent, slurry or gas phase conditions and related diluents or other mediums, reactor configuration, reaction temperatures, pressures, reactor residence times, use of transfer control agents, additives, and other conditions are well known to persons of skill in the art and can be selected based on the teachings of the examples herein Preferably, hydrogen is added in propylene polymerizations as hydrogen serves as a chain transfer agent which can impact catalyst activity as well as control polymer molecular weight EXAMPLES

Example I Preparation of bis-(l -naphthyl ^dimethoxysilane ("DNAMS")

A solution of 1 -bromonaphthalene (16 7 g) in 100 ml diethylether was added by addition funnel to magnesium (2 5 g) slurried in 100 ml of diethylether The reaction mixture was refluxed an additional 2 hours after the complete addition of 1 -bromonaphthalene The reaction mixture was decanted from unreacted Mg and most of the diethylether removed Pentane, 200 ml, was added to precipitate the desired magnesium salt This white solid was washed with additional pentane then dried to yield CioH7MgBr*Et2θi/2 (16 6 g) The magnesium salt was then added incrementally to a solution of S1CI4 (5 0 g) in 100 ml of toluene The reaction mixture was refluxed for 4 hours Crystallization of the final product began while allowing it to cool During this time pentane was added to increase the amount of precipitation A white solid yielded (8 7 g, 61%), bis-(l- naphthyl)silicondichloride To a solution of bis-(l-naphthyl)silicondichloride (2 0 g) in 60 ml of benzene, was added a solution of methanol (0 7 g) and pyridine (1.1 g) in 10 ml of benzene After 1 hour, the reaction was filtered and volatiles were removed in vacuo The resulting crude solid was washed with pentane (50 ml) then recrystallized from toluene to yield substantially pure bis-(l -naphthyl )dimethoxysilane as a white solid (0 9 g, 47 %) The resulting pure bis-(l -naphthyl )dimethoxysilane was diluted to a 0 IM solution in toluene, due to its insolubility in other non-polar organic solvents Example II

Preparation of 2-norbornyl-l-indenyldimethoxysilane ("NIMS")

Indenyllithium was prepared by reacting indene with one equivalent of methyllithium in diethylether Solid indenyllithium (0 034 mol) was placed in 50 ml of diethylether and was then added to a cold ether solution of 2-norbornyltrichlorosilane (0 034 mol) dropwise over approximately one hour The reaction was allowed to proceed overnight LiCl was then removed by vacuum filtration 2-norbornyl-l-(indenyl)dichlorosilane was purified via vacuum distillation (1 10-115°C @ 10 torr) Purification analysis by HNMR yielded 2- norbornyl-l-(indenyl)dichlorosilane, at 69 6% yield 2-norbornyl-l-

(indenyl)dichlorosilane (1 mol) was then reacted with an excess (4 mol) of a 1 1 molar equivalent mixture of anhydrous methyl alcohol and pyridine (anhydrous) This was accomplished by placing 2-norbornyl-l-(indenyl)dichlorosilane (1 mol) in 50 ml of diethylether, then adding the methyl alcohol/pyridine mixture slowly to it over 0 5 hr The reaction was allowed to proceed overnight A white precipitate, HCl'pyridine complex, was separated by vacuum distillation, and the distillation product (65 8% yield 2-norbornyl-l-indenyldimethoxysilane) was distilled at (160°C @ 0 torr) to yield a clear product having a purity by GCMS of 90% 2- norbornyl-1-indenyldimethoxysilane The distillation product was further purified by passing through a weak acid alumina column to obtain a final product having a purity, as measured by HNMR and GCMS, of 98 9% 2-norbornyl-l- indenyldimethoxysilane The final purified product 2-norbornyl-l- indenyldimethoxysilane was diluted to a 0 IM solution in pentane

All starting materials for donor synthesis of Examples I and II above were obtained from Gelest, Inc , Aldrich Chemical Co., or United Chemical Technology Analytical Procedures used for Examples III through VII

All polymer produced was stabilized with 0 1-0 6 wt% of 2,6-di-tert-butyl- 4-methylphenol by mixing the powdered 2,6-di-tert-butyl-4-methylphenol with the polymer particles or granules as the case may be, before the polymer was extruded "Activities" were calculated using an inductively coupled plasma emission spectroscopy (ICPES) determination of Mg content Approximately 20-100g of polymer sample is burned to ash. The ash is then digested in 3 ml of a first acid (HF) to remove silica and 3 ml of a second acid (HNO3) for dissolving the ash. A 4% boric acid solution (20 ml) is added as a buffer. The solution is then diluted to 100 ml and run through the ICPES to measure Mg levels in the ash. Mg level is used for calculating the amount of catalyst in the ash and activity. Activity is indicated by grams of polymer produced per gram of catalyst. Activity is calculated based on the Mg content of catalyst and Mg content in ash, as follows: Mg content in polymer can be obtained by ICPES in ppm wherein catalyst content in polymer (g) = ICPES Mg content ppm 10^"6 / Mg in catalyst powder (%) x 10^*^ and activity (g/g-cafhr) = 1 / cat content in polymer (g) x time of reaction (hr), or as % Mg in catalyst times 10"2 divided by parts per million Mg in ash times 10^*".

"Melting temperature (Tm)" and "crystallization temperatures (Tc)" of the polymers as well as the crystallinity ("Xc") were determined by differential scanning calorimetry ("DSC"). Xc was calculated by dividing the heat of fusion during crystallization of the melt (Joules/gram or ""J/g"), taken from the DSC, by 212 (J/g) which is the theoretical value for 100% crystalline isotactic polypropylene. The DSC instrument used was a DuPont 912 DSC equipped with a mechanical cooling accessory. Analysis was done on a TA2100 system. Method of analysis was as follows: (1) equilibrate at 25°C; (2) ramp 50°C / minute to 230°C; (3) isotherm for 10 minutes; (4) ramp 5°C / minute to 25°C; (5) ramp 10°C / minute to 230°C; (6) integrate heat area of crystallization "ΔH_C- (step 4) from 75°C to 140°C and (7) integrate heat area of melting "ΔH_m" (step 4) from 100°C to 175°C. ΔH_C generally correlates to polymer crystallinity, with some consideration of MFR effect on crystallinity. ΔH_C generally correlates to flex modulus.

"Melt Flow rate (MFR)" was measured by a Tinius Olsen Extrusion Plastometer (model UE-4-78 controller) equipped with a Tinius Olsen Elapsed Time Indicator (Digitimer). MFR were measured at 230.0±.1°C by adding 3-5 gms of polymer, (for MFR < 10 g/lOmin) containing approximately 0.02 g of stabilizer in the heating chamber of an extruder and allowing same to stabilize for 6 - 17 -

minutes. A timer is started when the timer arm comes into contact with a 2060 g weight, used to push the sample through the extrusion chamber. Piston travel distance for measurement is 1/4" for MFR 0.5 - 10 and 1 " for MFR >10. For 1" travel distance more sample should be used such as approximately 5-7 g. MFR was calculated as: MFR (g/10 min) = F / T (where F is factor below and T is time in seconds), where for polypropylene at 230°C: F = 801 (for 1" piston travel) and F = 200 (for 1/4" piston travel), and F = (427 x L x d); where 427 = mean of areas of piston and cylinder x 600; L = length of calibrated piston travel (cm); and d = density of resin at test temperature, g/cm-* (0.7386 for polypropylene). All methods and calculations are ASTM standards RR-D1238.

"Flexural Modulus (FM)", also called "Flex Modulus" was measured according to ASTM standard D-790 by using injection molded samples from a small injection molding machine which is a reciprocating screw-type machine having hydraulic clamping forces. Sample preparation of injection molded bars for flex modulus measurement was done by pelletizing 250-400 g samples with a 3/4" Killion Extruder. Injection molded bars were prepared on a lab scale 655 kPa (95 psi) Hi Tech Butler 10/90V Injection Molder.

"Molecular Weight Distribution (MWD)" was determined by a rheometric measurement analysis (RMA). A 2 gram sample is placed on parallel plates where a frequency sweep is done (0.1-100/sec"^) at 180°C. A correlation is developed where MWD is related to the crossover frequency for storage modulus/loss modulus (G'/G") curves. The MWD for polypropylene is determined by dividing 1 x lθ6 by the modulus (dynes/cm^) at the crossover point (G'/G").

Decalin solubles: Samples of selected weight (1 gram) of polypropylene are placed in an excess quantity of decalin (100 ml) and then are dissolved in the decalin by heating the combination while stirring to a temperature less decalin's boiling point. The heated solution is removed from heat, allowed to stand and cool to room temperature for 16 to 20 hours in order to cause the crystalline component of the polypropylene to precipitate. The precipitate is then filtered. After filtration, an aliquot of filtered solution is evaporated and weighed for a total solubles. Test Materials used in Examples III through VII:

Propylene: commercially available propylene of Exxon Chemical Company (99.8% pure propylene) was first passed in series through two 500 ml stainless steel vessels containing a bed of 3 A molecular sieves. The propylene was then passed through a 500 ml stainless steel vessel containing 1/8 inch beads of alumina (Selexorb COS, obtained from Alcoa Separations Technology, Inc. to selectively remove COS, CO2, H2S, & CS2. The propylene was further passed through 1/8 inch beads of alumina (Selexorb CD, also obtained from Alcoa Separations Technology, Inc) to selectively remove alcohols, ketones, aldehydes, carboxylic acids, and H S and other mercaptans.

Cocatalyst: triethylaluminum (TEAL) (1.0M in heptane) was obtained from Aldrich Chemical Co.

Hydrogen: hydrogen gas (99.99% purity from Matheson) was used after passing through a 500 ml stainless steel vessel containing an oxygen remover. This vessel was prepacked and purchased from Matheson as Model 64- 1050 A with a maximum flow of 50 SCFH (standard cubic feet per hour) and a maximum oxygen removal of 1% by volume.

Catalyst components: Commercially available catalyst components were obtained from Toho Titanium Company Limited, Japan (referred to herein as "TOHO A" and "TOHO B") and AKZO Chemical (referred to herein as "AKZO TK"). Titanium content in catalyst powder ranged from 2.0 wt% to 2.5 wt%, and magnesium content ranged from 15 wt% to 20 wt%. The catalyst components were received in a powder form and prepared with white oil as follows: (i) 9.85 g powder of catalyst TOHO A was placed in a 125 ml wheaton vial with 55.82 g of white oil (Precision-technical grade, purged for 24 h by nitrogen prior to use) and a magnetic stir bar. This 15 wt% dispersion was stirred overnight before use. The vial was wrapped in aluminum foil for protection from degradation and stored under a nitrogen atmosphere, (ii) 1.00g powder of catalyst TOHO B was placed in a 30 ml wheaton vial with 5.67 g of white oil to make a 15 wt% dispersion. All preparations were the same as with TOHO A. and (C) 10.00 g powder of catalyst AKZO TK was placed with 56.70 g of white oil to make a 15 wt% dispersion. All preparations were the same as with TOHO A.

External Donors: Tetraethoxysilane (TEOS) was acquired from Aldrich Chemical Co., product number 33,385-9. Cyclopentyl-t-butoxydimethoxysilane was obtained from Tonen Chemical Company. Dicyclopentyldimethoxysilane (DCPMS) was obtained from Shinetsu Chemical Company, Japan. Diphenyldimethoxysilane (DPMS) and tetramethoxysilane (TMOS) were obtained from Gelest, Inc. product numbers SID4535.0 and SIT7510.1, respectively. Dinorbornyldimethoxysilane (DNMS) was also acquired from Gelest, Inc. Dinaphthyldimethoxysilane (DNAMS) and norbomylindenyldimethoxysilane (NIMS) were prepared according to the procedures of Examples I and II, respectively

Polymerization Procedure used in Examples III through VII: A 2-liter zipperclave reactor was cleaned before each test run by washing the reactor with hot hexane for 15 minutes, followed by purging with nitrogen for 1 hour, with the reactor heated to an internal temperature of approximately 100°C. The reactor was allowed to cool to room temperature ( 25°C). A 10: 1 molar ratio mixture of triethylaluminum (IM in hexane) activator (also serving as scavenger) and external donor (0.1M in hexane) was fed through a feed tube into the reactor at room temperature while the reactor was lightly purged with nitrogen. The purging process was then stopped and 70 mmol of hydrogen was added to the reactor. While stirring the reactor contents, 1000 ml of propylene was added to the reactor. Approximately 40-60 mg of catalyst dispersion (catalyst component in mineral oil) was injected through the feed tube using 250 ml of propylene at room temperature as carrier. The reactor was then sealed. To reduce fines generated during polymerization, the polymerization initially allowed to proceed for 5 minutes at room temperature. The reactor temperature was then increased over a 5 minute period to 70°C, and polymerization was allowed to continue at 70°C for a total polymerization time of one hour. In all Tables herein, including Tables I through VII, donors have been identified by the following abbreviations: DNMS = dinorbornyldimethoxysilane; NIMS = norbomylindenyldimethoxysilane; TMOS = tetramethoxysilane; DCPMS = dicyclopentyldimethoxysilane; DNAMS = dinaphthyl dimethoxysilane; MCMS = methylcyclohexyldimethoxysilane; DPMS = diphenyldimethoxysilane; TEOS = tetraethoxysilane; and CPBS = cyclopentyl-t-butoxydimethoxysilane. Example III

The polymerization procedure described immediately above was conducted for different external donors using the Polymerization Materials also described above. Table I below sets forth the relevant polymer data:

Table I:

Donor Xc% Tm°C

TEOS 48.9 164.0

CPBS 47.3 162.2 161.7

DCPMS 54.1 164.5

DPMS 53.9 160.7

TMOS 47.6 159.6

DNMS 59.2 164.8

DNAMS 55.2 162.4

NIMS 60.4 163.4

For Examples IV through VII below, 0.6 gram of nucleating agent per 100 grams of polymer sample was added as a stabilizer during extrusion of the polymer to enhance the crystalline properties of the polymer. The nucleating agent consisted of a blend ("pbw", parts by weight) of 25 pbw sodium benzoate, 42 pbw sorbitol based nucleating agent (Millad 3988 obtained Milliken Chemicals), 8.3 pbw stablizer ( Cyanox 1790 obtained from Cytec Industries, Inc.); 8.3 pbw other stablizer (Ultranox 626 GE Chemicals), 8.3 pbw of a mold release agent (Acrawax C Lonza Inc.), and neutralizer (DHT4A, Kyowa Chemical Industries Company, Ltd, Japan).

Example IV

The polymerization procedures and materials used in Example III were repeated in this Example IV to produce polymer using the external donors methylcyclohexyldimethoxysilane (MCMS), dicyclopentyldimethoxysilane (DCPMS), dinorbornyldimethoxysilane (DNMS), dinaphthyl dimethoxysilane (DNAMS), and norbomylindenyldimethoxysilane (NIMS).

Table II below compares physical and mechanical properties of polymers made using various donors where the polymer produced was treated a nucleating agent.

Table II:

Property/Donor DNMS NIMS DNAMS MCMS DCPMS

MFR (range) <0.5 - 25 <0.5 - 116 0.5 - 120 0.5 - 40 0.5 - 25

MWD 5 - 6 6 - 7 7 - 8 4 - 5 4 - 5

Flex modulus (kpsi) 269 291 262 289 299 (MFR) (17) (20) (18) (18) (9)

Tm (^OQ 166.4 165.8 166.0 166.0 168.1

Tc (C) 131.7 129.4 132.2 131.0 130.9

Activity *(Kg/g^«cat^»hr) 40 30 31 31 40

Decalin Sol.(%) 1.7 2.2 3.1 1.9 1.1

We have thus found that using a first TOHO catalyst component with the donors of this invention that MWD and MFR are significantly broader than with other donors. This was confirmed by comparative testing of NIMS against DCPMS and MCMS with another TOHO catalyst component under the same polymerization conditions at a MFR of 5 0 ± 0.2, wherein the polymer of NIMS had a MWD of 6 8 and a flex modulus of 298kpsi after seven days of aging and DCPMS polymer had a MWD of 4.7 and a flex modulus of 302kpsi also after seven days of aging and polymer of MCMS had a MWD of 4 4 and a flex modulus of 287 kpsi after seven days of aging. Example V

The polymerization procedure of Examples I-IV was repeated in this Example V with the additional step of the addition of a titanocene hydrogenation catalyst at a concentration 25-to-l ratio (based on respective Ti content) of catalyst component to titanocene hydrogenation catalyst The hydrogenation catalyst consumes hydrogen and can enable production of a high molecular weight polymer fraction to broaden the MWD and possibly increase flexural modulus Preferably, a high crystalline fraction with MFR > 70 with a Flex Modulus > 260 kpsi is increased Bis(n-butylcyclopentadiene)titaniumdichloride (0 023 g, 6 37 x 10"⁵ m ), obtained from Boulder Scientific, was mixed with 0 38 ml of a 1 0M solution of triisobutylaluminum (obtained from Aldrich Chemical Co ) to solubilize such titanocene which would otherwise be insoluble in mineral oil To this solution, 24 6 g of mineral oil, which had been purged for 24 hours with nitrogen before use, was added to make a resulting solution of 15 % wt titanocene This solution turned light green initially and then within five minutes was light blue

At the catalyst component/hydrogenation catalyst Ti ratio of 25.1, we found that (a) catalyst activity (kg/g-cat/hr) was (i) 10 9 for TEOS, (ii) 14 5 for NIMS and (iii) 21 8 for DNAMS Hydrogen response was as shown in Table III

Table III DONOR Hydrogen Hydrogen Hydrogen concentration concentration concentration

(27 mmol) (109 mmol) (273 mmol)

DNAMS MFR=3.30 MFR= 19.66 MFR=82.65

NIMS MFR=3.23 MFR=30.81 MFR=97.09

Example VI

The polymerization procedure of Example V was repeated in this Example VI with the additional step of, after polymerizing for 1 hour at maximum hydrogen 1724kPa (250 psi) in the reactor, a titanocene hydrogenation catalyst was added to the reactor via 250 ml of propylene at a concentration ratio of 1 : 1 Ti of catalyst component: Ti of titanocene hydrogenation catalyst. This reaction was allowed to continue for an additional hour. The donor performance described in Table IV shows a larger MWD obtained by use of hydrogenation catalyst.

Table IV:

Donor Activity MFR MWD Tc Tm ΔHc Eex (kg g-h) Modulus g/10 min RMA (°C) (°C) (J/G)

(1% sec) (3) kpsi

NJMS^{( 1 )} 22 17 13.91 125.7 164.6 108.8 286.2

NIMS⁽²⁾ 37 8 7.26 133.2 167.1 118.2 ~

(') Data from use of titanocene hydrogenation catalyst in two step polymerization procedure as described in Example VI.

(2) Data from single step polymerization without added hydrogenation catalyst using procedure of Example IV. ΔH_ς = heat of crystallization Example VII

To evaluate performance of mixtures of extemal donors, the polymerization procedure of Example III was repeated in this Example VII, with the additional step of mixing two external donors, 50% by weight TEOS plus 50% by weight of the donor shown in Table VI. Comparative data for systems with single donors (100% one donor) was found to be as follows in Table V:

Table V:

Donor MFR

100% TEOS 722

100% DNMS 27

100% DNAMS 120

100% NIMS 116

Table VI:

Donor Activity MFR MWD Tc Tm ΔH Flex Modulus mix (kg/g-h) g/lOmin (^OC) (^OC) (J/G)

(1% sec)

50%

TEOS, kpsi plus

50% 31 56 6.59 132.9 165.9 117.9 283.5 DNMS

50% 35 141 — 126.9 164.9 116.4 ~

NIMS

50% 26 256 — 132.2 162.2 113.8 — DNAMS

Variations in the foregoing invention can be made without departing from the spirit and scope thereof.

Claims

CLAIMS We claim:

1. An olefin polymerization catalyst system comprising:

(a) a catalyst component comprising titanium, magnesium, and a first electron donor,

(b) an organometallic cocatalyst; and,

(c) one or more organosilanes having a structure:

R_^i X>Ry

Si R₂ ORz

wherein Rj and R2 are the same or different and are selected from the group consisting of alkyl radicals, cycloalkyi radicals, and polynuclear radicals, said polynuclear radicals having nine or more carbon atoms, wherein at least one of R] or R2 is a polynuclear radical of nine or more carbon atoms, with the proviso that where either R_] or R2 is indenyl or fluorenyl, the other of R or R2 is a substituted or unsubstituted bridged cyclic aliphatic radical or is a polynuclear aromatic radical often or more carbon atoms, and wherein Ry and Rz are the same or different and each Ry and Rz are selected from alkyl radicals having one or two carbon atoms;preferably wherein Rj is a polynuclear aromatic radical having ten or more carbon atoms, and wherein R2, Ry and Rz are the same or different and each

R2, Ry and Rz are selected from alkyl radicals having one or two carbon atoms, preferably wherein said organosilane is one of bis-(naphthyl)dimethoxysilane or norbomylindenyldimethoxysilane.

2. The catalyst system of claim 1 wherein said polynuclear radical is selected from the group consisting of naphthyl; alkylnaphthyls; phenylnaphthyl; anthracyl; phenanthryl; l-methyl-7-isopropylphenanthryl; halonaphthyls; nitronaphthyls, and amine substituted naphthyls and mixtures thereof atoms.

3. The catalyst system of claim 1 wherein said organometallic cocatalyst is a metal alkyl selected from the group consisting of metal alkyls selected from the group consisting of A1(CH₃)₃, A1(C₂H₅)₃, A1(C₃H₇)₃, A1(C₄H₉)₃, Mg(CH₃)_2j Mg(C₂H₅)₂, Mg(C₂H₅)(C₄H₉), Mg(C₄H₉)₂, Zn(CH₃)₂, Zn(C₂H₅)₂, and Zn(C4H9)₂ and mixtures thereof.

4. A process for polymerizing one more alpha-olefins comprising contacting, at polymerization conditions, said one or more alpha-olefins with the catalyst of any one of the preceeding claims

5. A process for polymerizing ethylene and one or more alpha-olefins comprising contacting, at polymerization conditions, said ethylene and one or more alpha-olefins with a catalyst system of any one of claims 1-3.

6. A process for polymerizing ethylene comprising contacting, at polymerization conditions, said ethylene with a catalyst systemof any of claims 1-3.

7. The process of any of claims 4-6 wherein said polymerization is conducted in the presence of hydrogen.

8. The process of any of claims 4-6 wherein said polymerization is conducted comprising conducting said polymerization in the presence of a metallocene.

9. Norbomylindenyldimethoxysilane having the formula (C₇H_{1 1})(C₉H₇)Si(OCH3)2

10. A method to prepare norbomylindenyldimethoxysilane comprising: a. reacting indene with methyllithium in a diluent to form indenyllithium; b. reacting said indenyllithium with norbornyltrichlorosilane in a solvent to form LiCl and norbornylindenyldichlorosilane; c. separating said LiCl from said norbornylindenyldichlorosilane; d. reacting said norbornylindenyldichlorosilane with methyl alcohol and pyridine in presence of a first solvent to form a HCl-pyridine complex and norbomylindenyldimethoxysilane; e. separating said HCl'pyridine complex from said norbomylindenyl¬ dimethoxysilane, and, f. recovering said norbomylindenyldimethoxysilane.

11. Dinaphthyldimethoxysilane having the formula (C j oH7)2Si(OCH3)2.

12. A method to prepare bis-(naphthyl)dimethoxysilane comprising: a. reacting bromonaphthalene with magnesium to form a magnesium salt CιoH7MgBr^«(CH3CH₂)2θ)x, where x > 0; b. reacting said salt with S1CI4 in the presence of a first solvent at an elevated temperature to form a heated solution containing bis-(naphthyl) silicondichloride; c. cooling said heated solution to crystallize at least a portion of said bis-(naphthyl)silicondichloride; d. separating said first solvent from said bis-(naphthyl) silicondichloride; e. reacting bis-(naphthyl)silicondichloride with pyridine and methanol in the presence of a second solvent to form bis-(naphthyl)dimethoxysilane; and f recovering said bis-(naphthyl)dimethoxysilane.

13. A true polymer of propylene having a crystallinity melt temperature exceeding 164°C, a percent crystallinity exceeding 55%, and a molecular weight distribution of from 6 to 10.