WO2008112133A2

WO2008112133A2 - Pyridlyamidohafnium catalyst precursors, active species from this and uses thereof to polymerize alkenes

Info

Publication number: WO2008112133A2
Application number: PCT/US2008/003010
Authority: WO
Inventors: Geoffrey W. Coates; Gregory J. Domski
Original assignee: Cornell University
Priority date: 2007-03-13
Filing date: 2008-03-07
Publication date: 2008-09-18
Also published as: WO2008112133A3

Abstract

Cs-Symmetric pyridylamidohafhium catalyst precursors and active species based thereon are described. The active species are used for living polymerization of C2-C20 alkenes and provide highly isotactic polypropylene and are useful to provide multi-block copolymer with end blocks of isotactic polypropylene or isotactic poly(4-methyl-1-pentene).

Description

PYRIDLYAMIDOHAFNIUM CATALYST PRECURSORS, ACTIVE SPECIES FROM THIS AND USES THEREOF TO POLYMERIZE ALKENES

This invention was made with U.S. Government support at least under National Science Foundation Grant Number DMR-0520404. The Government has certain rights in the invention.

Cross-Reference to Related Applications

This application claims the benefit of U.S. Provisional Application Number 60/906,512 filed March 13, 2007, the whole of which is incorporated herein by reference.

Background of the Invention

Activated Cj-symmetric dialkyl pyridylamidohafnium compounds are known which are used for the high temperature isoselective polymerization of propylene and for polymerization of various vinyl monomers. When these known compounds are activated to produce active species, the active species have limited usefulness for living polymerization of alkenes. The inventors here have found that the Ci- symmetric catalysts give broad molecular weight distribution (PDI > 1.5 for polymers of propylene and 1-hexene).

Summary of the Invention

It has been discovered herein that certain other activated pyridylamidohafnium catalyst precursors where the substituent on carbon between the pyridyl moiety and amino nitrogen is hydrogen or Ci-C₅ alkyl or silyl (-SiH₃), are useful to catalyze living polymerization of alkenes and also provide polymerization of propylene and 4- methyl-1-pentene with high isotacticity, e.g. greater than 50% [m⁴], for polypropylene as determined by integration of the methyl region of the ¹³C NMR spectrum. The [m⁴] value cannot be calculated for poly(4-methyl-l-pentene) using ¹³C NMR or any other technique as far as we are aware. A technique for determining crystallinity and hence isosotacticity for poly(4-methyl-l-pentene) is differential scanning calorimetry (DSC).

One embodiment of the invention herein, denoted the first embodiment, is directed at pyridylamidohafnium catalyst precursors having the structure

where R¹ and R² are both hydrogen, or selected from the group consisting of Ci-C₅ alkyl, silyl, and combinations thereof, and optionally, R¹ and R² may be joined together in a ring structure narrowed to avoid prior art, where each of R³, R⁴, R⁵, R⁶, R⁷, R⁸, R⁹, R¹⁰, R¹¹, R¹², R¹³, R¹⁴ is independently selected from the group consisting of hydrogen, Cj-C₅ alkyl, silyl, and combinations thereof, and optionally, any combination of R³, R⁴, R⁵, R⁶, or R⁷, any combination of R⁸, R⁹, or R¹⁰, and any combination of R¹¹, R¹², R¹³, or R¹⁴ may be joined together in a ring structure, where each of R¹⁵ and R¹⁶ is independently selected from the group consisting of halide, C]-C₅ linear or branched alkyl or benzyl, Ci-C₂ alkoxy, or optionally R¹⁵ and R¹⁶ may be joined together in a ring structure.

Another embodiment herein, denoted the second embodiment, is directed to active species generated from reaction of the compound of formula (I) and an activator.

Still another embodiment herein denoted the third embodiment is directed at diblock copolymer, triblock, or multiblock copolymer prepared using the active species of the second embodiment comprising in polymerized form propylene and one or more copolymerizable comonomers other than propylene, said copolymer containing therein two or more segments or blocks differing in comonomer content, crystallinity density, melting point or glass transition temperature.

Yet another embodiment herein denoted the fourth embodiment is directed to a method of living polymerization of a C₂-C_2O alkene in a non-polar non-protic solvent carried out in the presence of the active species of the second embodiment, thereby providing a polydispersity index of no more than 1.30, e.g. less than 1.25, e.g. less than 1.20, e.g. less than 1.10.

Yet another embodiment herein denoted the fifth embodiment is directed at a diblock copolymer, triblock copolymer, or multiblock copolymer prepared using the active species of the second embodiment comprising in polymerized form 4-methyl-l- pentene and one or more copolymerizable comonomers other than 4-methyl-l- pentene, said copolymer containing therein two or more segments or blocks differing in comonomer content, crystallinity, density, melting point or glass transition temperature.

As used herein the term living polymerization means addition polymerization where the ability of a growing polymer chain to terminate has been removed and a polydispersity index of 1.30 or less is obtained. In determining polydispersity index, M_n and M_w are determined using gel permeation chromatography in 1,2,4-C₆H₃Cl₃ at 140°C vs polystyrene or polyethylene standards.

Detailed Description

We turn now to the first embodiment of the invention herein.

The pyridylamidohafnium precursor of structure (I) preferably has Cs symmetry or pseudo-Cs symmetry (very close to Cs symmetry). The terms Cs and pseudo-Cs symmetry mean that the entire compound is symmetric with respect to a bisecting mirror plane passing through bridging group and the atoms bonded to the bridging group, i.e. the substituents on each coordinating group of a bridged ligand, which are reflectively coupled, are identical or similar. Cs or pseudo-Cs symmetry also means that the coordinating groups are bilaterally or pseudobilaterally symmetric.

The pyridylamidohamium catalyst precursors as described above have an angle < CNC depicted below in structure (I) larger than 114 degrees

The angle CNC changes based on the steric demands of R¹ and R². As this angle increases the stereoselectivity of the activated catalyst precursor increases. The angle is determined by X-ray crystallography or is determined based on optimized structure by a Density Functional Theory (DFT) calculation using Gaussian 03 (latest in the Gaussian Series of electronic programs used by chemists) and Becke 3-Parameter (Exchange), Lee, Yang and Parr (correlation, density functional theory) (B3LYP) where Los Alamos National Laboratory 2-double-z (density functional theory) (LANL2DZ) is used as a basis set for Hf and 3-2 IG for H, C and N.

Subgenera of pyridylamidohafhium catalyst having structure (I) have the structures

and

where R¹⁷ and R²¹ are selected from H and methyl, where R¹⁸ and R²² are selected from isopropyl and tert-butyl, where R¹⁹ and R²³ are selected from H, isopropyl and tert-butyl and where R²⁰ and R²⁴ are selected from C₁-C₄ linear or branched alkyl and benzyl.

Species having the structure (II) include those where:

(a) R¹⁷ is H, R¹⁸ is isopropyl, R¹⁹ is H and R²⁰ is methyl (denoted precursor (1) hereinafter),

(b) R¹⁷ is H, R¹⁸ and R¹⁹ are tert-butyl and R²⁰ is methyl (denoted precursor (3) hereinafter), and

(c) R¹⁷ is methyl, R¹⁸ is isopropyl, R¹⁹ is H and R²⁰ is methyl (denoted precursor (5) hereinafter).

Species having the structure (III) include those where:

(a) R²¹ is H, R²² is isopropyl, R²³ is H and R²⁴ is methyl (denoted precursor (2) hereinafter),

(b) R²¹ is methyl, R²² is isopropyl, R²³ is H and R²⁴ is methyl (denoted precursor (6) hereinafter).

The precursors can be made as follows: Pyridylimine ligand precursors of the catalyst precursors are prepared via a Schiff Base condensation between 6-phenyl-2- pyridine carboxaldehyde (for II) or 6-naphthyl-2-pyridinecarboxaldehyde (for III) and the appropriate aniline, e.g. 2,6-diisopropylaniline, 2,4,6-tri-tert-butylaniline, etc.

The imines are then reduced with either LiAlH₄ or more preferably with NaBH₃CN with catalytic formic acid to give the corresponding pyridylamine ligand. The resulting amines can be reacted with BuLi to obtain pyridylamido lithium salt which is reacted with HfCl₄ to form trichloropyridylamidohafhium intermediate which is reacted with MeMgBr to provide catalyst precursor.

To obtain 6-phenyl-2-pyridine carboxaldehyde, 6-bromo-2-pyridine carboxaldehyde (Aldrich) can be reacted with Pd(PPh₃)₄ and phenylboronic acid with the addition OfNa₂CO₃ by refluxing, e.g. for two hours.

To obtain 6-naphthyl-2-pyridine carboxaldehyde, 6-bromo-2-pyridine carboxaldehyde is reacted with 1 -naphthalene boronic acid, Pd(PPh₃)₄ and Na₂CO₃.

In the making of precursor imine corresponding to catalyst precursor (1) 6- phenyl-2-pyridine carboxaldehyde is reacted with 2,6-diisopropylaniline in EtOH with the addition of formic acid. hi the making of precursor imine corresponding catalyst precursor (3), 2,4,6- tritertbutylaniline is used instead of 2,6-diisopropylamine in the reaction of the above paragraph.

To obtain imine corresponding to catalyst (2), reaction is carried out the same as for precursor imine corresponding to catalyst precursor (1) but 6-naphthyl-2- pyridine carboxaldehyde is used instead of 6-phenyl-2-pyridine carboxaldehyde.

The imine precursors were converted to catalyst precursors as shown in working examples.

Synthesis of catalyst precursors 5 and 6 is shown in working examples.

We turn now to the second embodiment of the invention herein. In a preferred case, activator for the active species is B(C₆Fs)₃. Methylaluminoxane as activator at low loadings also gives polypropylene with narrow polydispersity indices.

To provide pyridylamidohafnium precursor activated with B(C₆Fs)₃, the two can be brought together in the presence of alkene to be polymerized. The [HfJ: [B] mole ratio ranges for example from 0.5:1 to 1.5:1 and is preferably 1 :1.

We turn now to the third embodiment.

The copolymerizable monomers other than propylene, are C₂-C₂₀ alkenes different from propylene, e.g. ethylene.

One case of the third embodiment is a triblock copolymer where end blocks are isotactic polypropylene ([m⁴]>50%) having M_w/M_n of 1.30 or less, e.g. less than 1.25, e.g. less than 1.20, e.g. less than 1.10 and a midblock of poly(ethylene-co- propylene), where the block lengths of the end blocks range from 20 to 200 kg/mol and the block lengths for midblocks range from 100 to 500 kg/mol and the M_n for the triblock polymer ranges from 100 to 1,000 kg/mol determined via GPC in 1, 2, 4- C₆H₃Cl₃ at 140°C vs PE standards and the MJM_n for the triblock copolymer is 1.30 or less. The triblock copolymer is prepared by method comprising the steps of in a reactor initiating propylene polymerization at a temperature ranging from e.g. from 0 to 50°C, e.g. from 0 to 20°C, e.g. from 0 to 10°C in a non-polar non-protic solvent in the presence of the active species of the second embodiment to obtain a first isotactic polypropylene end block, introducing an overpressure of ethylene into the reactor to obtain a poly(ethylene-co-propylene) midblock, venting the ethylene and reestablishing the propylene feed at the propylene pressure for the first block to obtain a final polypropylene block. The non-polar, non-protic solvent can be, for example, toluene, benzene, xylene, hexane, heptane or methylene chloride. The propylene pressure in the reactor ranges, for example, from 5 psig to 50 psig.

In another case, the third embodiment is directed to a multiblock copolymer where the number of segments is not less than three and the end blocks are isotactic polypropylene and the end blocks are obtained by polymerizing propylene as in the paragraph directly above, and the segments between are obtained by introducing overpressure of monomer for a segment between and cycling between that monomer and other monomer or propylene with venting between segments and introducing propylene for the end block. The M_n for the multiblock copolymer ranges from 100 to 1,000 kg/mol determined via GPC in 1,2,4-C₆H₃Cl₃ at 140°C vs PE standards and the end blocks are isotactic polypropylene with polydispersity index of 1.30 or less, e.g. less than 1.25, e.g. less than 1.20, e.g. less than 1.10, with block lengths ranging from 20 to 200 kg/mol.

We turn now to the fourth embodiment of the invention. The alkene can be for example a C₃-C₂₀ α-olefin, e.g. propylene or 1-hexene. In general, the temperature of reaction ranges from 0 to 50⁰C, e.g. 15 to 40°C, e.g. 20 to 30⁰C. For 1-hexene the mole ratio of 1-hexene to Hf is greater than 1,000 and the temperature of reaction is preferably 20 to 30⁰C. For propylene, the mole ratio of propylene to Hf is considered to be greater than 1,000 and the temperature of reaction is preferably 10 to 35°C, e.g. 10 to 20⁰C or 25 to 35°C. For propylene the pressure in the reactor ranges from 5 psig to liquid propylene. The reaction solvent is a non-polar, non-protic solvent e.g. toluene, benzene, xylene, hexane, heptane or methylene chloride or the monomer itself can be said solvent, e.g. in propylene bulk polymerization. The polymerization is preferably carried out using active species where the catalyst precursor is selected to obtain an isotacticity, [m⁴] of at least 50%, e.g. more than 90%.

We turn now to the fifth embodiment.

The copolymerizable monomers other than 4-methyl-l-pentene are C₂-C₂₀ alkenes, e.g. ethylene or propylene.

One case of the fifth embodiment is a triblock or multiblock copolymer where the end blocks are isotactic poly(4-methyl-l-pentene) and poly(ethylene-co-4- methyll-pentene) is included as a midblock and the block lengths for the end blocks range from 20 to 300 kg/mol and the block lengths for midblocks range from 100 to 500 kg/mol and the M_n for triblock copolymer ranges from 5,000 g/mol to 500,000 g/mol as determined via GPC in 1, 2, 4-C₆H₃Cl₃ at 140°C vs. PS standards and M_w/M_n for the triblock is 1.30 or less, e.g. 1.15 or less and the T_m for the triblock exceeds, for example, 190°C.

Another case of the invention herein is directed to a method of preparing isotactic poly(4-methyl-l-pentene) comprising polymerizing 4-methyl-l-pentene at a temperature ranging from 0 to 50°C in a non-polar non-protic solvent in the presence of the active species of the second embodiment where the [Hf]: [B] mole ratio in the active species ranges from 0.5:1 to 1:5 where the mole ratio of 4-methyl-l-pentene to Hf is greater than 1 ,000 and of preparing a block copolymer with isotactic poly(4- methyl-1-pentene) end blocks and a poly(ethylene-co-4-methyl-l-pentene) midblock comprising in a reactor initiating polymerization of 4-methyl-l-pentene according to the aforedescribed method to provide a first isotactic poly(4-methyl-l-pentene) block, introducing and establishing an ethylene overpressure of 5-50 psig in the reactor to form a poly(ethylene-co-4-methyl-l-pentene) midblock, venting the ethylene and allowing polymerization of 4-methyl-l-pentene to proceed to form a final isotactic poly(4-methyl-l-pentene) end block. M_n for isotactic poly(4-methyl-l-pentene) can range, for example, from 5,000 g/mol to 500,000 g/mol as determined via GPC in 1,2,4-C₆H₃Cl₃ at 14O⁰C vs PS Standards.

Elements of the invention and working examples are set forth in Domski, GJ., Lobkovsky, E.B. and Coates, G.W., Macromolecules 40, 3510 - 3513 (2007) the whole of which is incorporated herein by reference and in Supporting Information for said article, the whole of said Supporting Information being incorporated herein by reference.

The invention is illustrated by the following working examples. Working Example I

Preparation of Catalyst Precursor (1) Having the Structural Formula (U) where R¹⁷ is H, R¹⁸ is Isopropyl. R¹⁹ is H and R²⁰ is Methyl

1

The compound (1) was prepared following the general procedure described by Coalter, J.N., EI, et al. WO 2003/040195A1. First 2,6-diisopropyl-N-((6- phenylpyridine-2-yl)methyl)aniline intermediate was prepared as detailed in Supporting Information for Domski, GJ., et al., Macromolecules 40(a), 3510 - 3513 (2007). This intermediate (0.629g, 1.83 mmol) was dissolved in the minimum amount of dry toluene and cooled to 0°C. BuLi (1.20 mL of a 1.6 M solution in hexanes) was added to the ligand solution under N₂. Upon addition of the BuLi solution a yellow precipitate formed. After 1 h, the volatiles were removed in vacuo. The resulting residue was slurried in hexane, the supernatant was removed via cannula, and the resultant yellow powder was dried in vacuo. Fresh toluene was added to the ligand salt, and the resulting slurry was transferred via cannula to a slurry Of HfCl₄ (0.529 g, 1.65 mol) in toluene. The resulting mixture was heated to 110°C, resulting in a color change from yellow to orange. After 3 h, the reaction mixture was cooled to room temperature, and 1.92 mL of 3.0 M MeMgBr in Et₂O was added. The reaction mixture turned from orange to red. After 12 h the volatiles were removed in vacuo. The residue was extracted with toluene, the extracts were filtered through Celite, and the volatiles were removed in vacuo to give a white crystalline solid. Recrystallization from toluene at -35°C yielded orange, single crystals (0.57 g, 63% yield) suitable for X-ray diffraction. ¹H NMR (C₆D₆, 500 MHz): δ 8.34 (dd, J_HH=5.37 HZ, 1.47. IH, ArH). 7.38 (td, J_ΗΗ=6.15 Hz, 0.98 Hz, IH, ArH), 7.26-7 - 7.17 (m, 4Η, ArH), 6.94 (d, 1Η, ArH), 6.88 (t, J_ΗΗ=7.81 Hz, IH, ArH), 6.31 (d, J_ΗΗ=7.81 HZ, IH, ArH), 5.07 (s, 2Η, CH₂N), 3.73 (q, J_ΗΗ=6.84 Hz, 2H, CH(CH₃)₂), 1.37 (d, J_HH= 6.84 Hz, 6H, CH(CH₃)₂), 1.21 (d, J_HH= 6.84 Hz, 6H, CH(CH₃)₂), 0.68 (s, 6H, Hf-CH₃). i₃C{1H} NMR (C₆D₆, 125 MHz): δ 166.54, 164.99, 148.18, 147.65, 141.04, 139.03, 131.13, 128.88, 128.79, 126.97, 124.88, 124.46, 123.46, 118.07, 115.58, 68.67, 64.85, 28.75, 28.34, 24.37. Elemental analysis: Calcd for C₂₆H₃₂HfN₂: C, 56.67%; 5.84%; N, 5.08%, Found: C, 56.42%, H, 5.84%; N. 5.18%.

Working Example II Preparation of Catalyst Precursor (2)

This compound was prepared the same as catalyst precursor (1) except that an equimolar amount of 6-naphthyl-2-pyridine carboxaldehyde was substituted for the 6- phenyl-2-pyridine carboxaldehyde (made according to the procedure set forth in the Supporting Information described above).

Working Example III Preparation of Catalyst Precursor (3)

Preparation of catalyst precursor (3) was carried out the same as for catalyst precursor (1) except that an equimolar amount of 2,4,6-tri-tert-butylaniline was substituted for the diisopropylaniline (see reaction of 6-phenyl-2-pyridine carboxaldehyde and diisopropylaniline described in the Supporting Information above).

Working Example IV Preparation of Catalyst Precursors (5) and (6)

Syntheses of (5) and (6) were carried out according to the following procedure:

2 AlMe₃ 1. BuLi, Toluene, 0 °C

Toluene, 110 °C 2. HfCI₄, Toluene, 110 °C '

3. 3.5 equiv MeMgBr

To prepare the ketimine precursor, 6-acetyl-2-bromopyridine, Pd(OAc)₂, PPh₃, K₂CO₃ and either phenyl boronic acid or 1 -naphthalene boronic acid were allowed to react in refluxing dimethoxyethane (DME) to furnish after work up and purification 6-acetyl- 2-phenylpyridine or 6-acetyl-2-(l-naphthyl)pyridine. These products were then allowed to react with 2,6-diisopropylaniline in EtOH with a catalytic amount of formic acid at 70 °C to furnish the corresponding ketimines.

Working Example V Polymerization of 1-Hexene

The data is presented in Table 1 below where (1) is catalyst precursor (1) prepared in Working Example I, rac-2 was prepared as described at S8 and S9 of the Supporting Information referred to above and is in the prior art. The compound rac-3 was prepared as described at pages 5-9 and S-IO of said Supporting Information.

The compound rac-2 has formula (II) where one R¹⁷ is H and the other is Ph, R¹⁸ is isopropyl, R¹⁹ is H and R²⁰ is methyl.

The compound rac-3 has the formula (II) where R¹⁷ is H, R¹⁸ is 1-(4-¹Bu- C₆H₄)Et, R¹⁹ is methyl and R²⁰ is methyl.

Compound (1) has Cs symmetry. Compounds rac-2 and rac-3 have Ci symmetry.

Table 1 referred to above follows. The activators B(C₆F₅)₃ and [Ph₃C] [B(C_όF₅)₄] referred to therein are commercially available. Table 1

M_n' entiy cat activ nlor ;_α.*(mui) »_m (h) WO yield (?) coπv Ci) (g/uiol) (e/inol) MJSW

1 1 360 2 0 25 0 0 u a '

I B(C₆FOi 60 2 0 25 0.03 106 000 30000 4 52

I B(C₆Fj)₃ 5 2 0 25 34 99 ~ 2S4 300 134 000 1 09

4 I B(C₆F₅)J 0 2 0 25 34 99 152 000 134 000 1 15

5 1 B(C₆Fj)₃ 0 0 5 0 ) 13 9 6 51 200 13 000 1 20

6 I B(C₆F₅)J 0 0.5 25 13 83 133 200 1 13 000 1 07

7 I B(C₆FOi 0 0 5 50 05 77 150 SOO 105 000 1 IS

8 I [Ph₃C][B(C₆Fi)₄] 0 2 0 25 13 9S 267 000 133 000 1 33

9 I [Ph₁C][B(C₆F,)^ 0 0 5 0 29 95 520 300 129000 1 51

10 B(C₆F*)* 0 0 5 25 .33 98 148 600 m ooo 1 51

U -ac-3 B(C₆F₅). 0 24 25 ) 05 3 7 153 SOO 5000 1 61

" Polymerization conditions- Hf = 10 /irnol, [HfJZ[B] = I 0. 8 0 uiL toluene. 2 0 mL 1-hexene * (.„ = period that precatalysi and acmatoi were in contact prior to introduction of the monomer ' Determined using gel penneatiou chromatography ui 1,2,4-C₆HjCI₃ at 140 °C vs polystyrene standards ^d u a = not applicable

Working Example VI Polymerization of Propylene

The following compounds were used as catalyst precursors for polymerization of propylene with results shown in Table 2 below.

Compound (1) is the precursor catalyst (1) of Working Example I. Compound (2) is the precursor (2) of Working Example III. The compound rac-4 is the same as the compound rac-2 of Working Example V. The compounds (5) and (6) are the same as precursor catalysts (5) and (6) of Working Example IV. Compound 7 was made by a method analogous to that used to prepare (5) and (6) using AlEt₃ instead of AlMe₃. The compounds 1, 2, 3, 5, 6, 7 have Cs symmetry. The compound rac-4 has Ci symmetry. Table 2 follows. Table 2

(10)

T 5 (10) B(C₆Fj)₃ 15 0.55 141,200 1.21 92 -8.1 140.4

8^A 5 (10) [Ph₃C][B(C₆Fs)₄] 15 5.05 238,700 2.84 88 -8.9 140.6

9^C 6 (10) B(C₆Fs)₃ 15 2.62 265,900 1.23 91 -6.6 133.0

10 7 (10) B(C₆Fs)₃ 15 2.16 132,700 1.36 82 -4.9 128.0

Catalyst was injected with 5 mL of toluene into a 10 mL toluene solution of activator (1 equiv.) with constant 30 psig propylene feed at 20 °C. ^Catalyst and activator (1 equiv.) were combined in 10 mL of toluene and injected into 20 mL toluene with constant 30 psig propylene feed at 20 °C. ^cCatalyst was injected with 5 mL of toluene into a 25 mL toluene solution of activator (1 equiv.) with constant 30 psig propylene feed at 20 °C. ^Determined via GPC in 1,2,4-C₆H₃Cl₃ at 140 °C vs PE standards, determined via integration of the methyl region of the ¹³C NMR spectrum, determined via DSC (second heating).

Working Example VII Propylene Polymerization with 6/[B(CnFQjI for Different Durations

Data and conditions are presented in Table 3 below.

Table 3 time Yield M_n ^meo'^b M_n ^c

Entry (min) (g) (g/mol) (g/mol) MJM_a ^c

1 1.5 0.63 63,000 36,700 1.17

2 3.0 1.27 126,900 101,800 1.07

3 6.0 1.86 186,000 136,600 1.23

4 12.0 2.66 266,000 239,500 1.20

"General conditions: Catalyst (10 μmol) was injected with 5 mL of toluene into a propylene-sarurated (30 psig) solution of B(C₆F₅)₃ (10 μmol) in 25 mL of toluene. Polymerization was allowed to proceed at 20 °C with constant propylene feed (30 psig). ⁶M_n*⁶⁰ = g PP/mol Hf. determined via GPC in 1,2,4-C₆H₃Cl₃ at 140 °C vs PE standards.

Working Example VIII

Preparing Triblock Copolymer with Isotactic Polypropylene End Blocks and Polv(ethylene-co-propylene) Mid-Block

Data and conditions are set forth in Table 4 below.

Table 4 entry ^(C₃H₆) P(C₂H₄) t_b" Block MJM_B ^C Wt. %

(psig) (min) (psig) (min) (min) Lengths** (ABA) (ABA) (iPP)

(kg/mol) (kg/mol)

1 30 2.5 45 7.5 5 50-165-30 245.2 1.19 33

2 30 2.5 45 7.5 10 48-173-71 292.0 1.30 40

3 30 2.5 45 10 7.5 46-188-29 263.5 1.28 29

"General conditions: A toluene solution Of B(C₆Fs)₃ (10 μmol in 45 mL) was cooled to 0 °C and saturated with propylene. Catalyst (10 μmol) in 5 mL of toluene was injected. After the desired period of time (t_a), ethylene overpressure was established and polymerization continued for %. Ethylene was vented and the propylene feed was reestablished. Polymerization was allowed to continue for t_c. ^Determined from GPC analysis of quenched aliquots removed from polymerization reactor. ^cDetermined via GPC in 1,2,4-C₆H₃Cl₃ at 140 °C vs PE standards.

Working Example IX Polymerization of 4-Methyl- 1 -Pentene Data and results are set forth in Tables 5 A and 5B below.

Table 5A cat. [cat] [4MP]₀ entry" (μmol) (mM) Activator (M) (min)

1 1 (10) 1 0 B(C₆Fs)₃ 1 ₅8 60

2 2 (10) 1 0 B(C₆Fs)₃ 1 58 30

3 3 (10) 1 0 B(C₆Fs)₃ 1 ₅8 60

4 5 (10) 1 0 B(C₆F₅), 1 ₅8 30

5 S (IO) 2 0 B(C₆Fs)₃ 3 17 30

6 5 (10) 1 0 B(C₆Fs)₃ 0 79 30

7 5 (10) 1 0 B(C₆F₅), 3 17 30 g 5 (10) 1 0 B(C₆Fs)₃ 1 58 30

9 5 (10) O ₅ [Ph₃C][B(C₆Fs)₄] 0 79 30

10 5(10) O ₅ [Ph₃C][B(C₆Fs)₄] 0 40 30

1 1 5 (10) O ₅ [Ph₃C][B(C₆Fs)₄] 0 40 30

12 5 (10) O ₅ [Ph₃C][B(C₆Fs)₄] 0 40 30

13 5 (10) 1 0 [Ph₃C][B(C₆Fs)₄] 1 58 30

14 6 (10) 1 0 B(C₆Fs)₃ 1 58 30

I₅ 6 (10) O ₅ B(C₆Fs)₃ 0 79 30

16 6 (10) 1 0 B(C₆Fs)₃ 1 58 30

17 6 (10) 1 0 B(C₆Fs)₃ 1 58 30

18 6 (1) 0 5 [Ph₃C][B(C₆Fs)₄] 0 40 30

19 6 (1) 0 5 [Ph₃C][B(C₆Fs)₄] 0 40 30

20 6 (1) 0 5 [Ph₃Cl[B(C₆Fs)₄I 0 40 30 Table 5B

T_^ yield conv. Λ/_n ^δ T ^c entry" (⁰C) (ε) (%) (g/mol) MJM_D ^b (⁰C) ("O

1 25 0.39 29 190,100 1.19 88.5 190.6

2 25 1.06 79.7 180,500 1.15 86.1 202.0

3 25 0.22 17 51,000 1.85 88.2 231.4

4 25 0.62 47 51,300 1.92 n.d." 232.3

5 25 1.31 98.5 21,400 2.95

6 25 0.29 43.6 29,000 2.01

7 25 2.30 86.5 19,900 4.35

S 0 0.02 1 54,500 1.68

9 25 1.22 91.7 10,800 2.95

10 25 0.65 97.7 17,900 2.50

11 0 0.51 76.7 139,200 1.38

12 -20 0.01 2 85,800 1.48

13 0 1.33 >99 196,200 1.33

14 25 1.30 97.7 15,900 2.66

15 25 1.27 95.5 40,100 2.23

16 0 0.84 63 226,900 1.36 n.d." 237.6

17 -20 0.24 18 178,100 1.41 n.d." 238.8

18 25 0.66 99 35,500 2.04

19 0 0.67 >99 160,300 1.31

20 -20 0.57 86 227,900 1.39

The footnotes for the columns in Tables 5A and 5B are as follows: aGeneral Conditions: Activator (1 equiv.) was dissolved in toluene; monomer was added to this solution. The activator solution was cooled to the desired temperature when sub-ambient temperatures were employed. The catalyst was dissolved in toluene and injected into the monomer/activator solution. ^bDetermined via GPC in 1,2,4,-C₆H₃Cl₃ at 140⁰C vs PS standards, determined via DSC (second heat). ^dn.d. = none detected.

The melting points of entries 1 and 2 in Table 5B indicate modest levels of isotacticity and the melting points for entries 3 and 4 in Table 5B indicate high levels of isotacticity.

Working Example X

Preparing Triblock Copolymer with Iso tactic Poly(4-Methyl-1-Pentene) End Blocks and a Polv(Ethylene-co-4-Methyl-l-Pentene Mid-Block Using 2/B(CJOi Catalyst

Conditions and results are set forth in Table 6 below. Table 6 entry [4MP]₀ Block M_a ^c MJM_a ^c j a

Wt. %

(M) (⁰C) Lengths'" (ABA) (ABA) (iP4MP) (ABA) (ABA)

(kg/mol) (kg/mol) (⁰C) (⁰C)

1 1.13 20 48-317-55 418.8 1.10 25 -39.6 202.4

2 0.26 20 42-165-65 272.4 1.09 39 -25.7 203.7

3 0.31 0 32-192-187 412.0 1.09 53 -46.9 208.7

"General conditions: A toluene solution of B(C₆F₅)₃ (10 μmol in 25 mL) containing 4MP was placed in the polymerization reactor. Catalyst (10 μmol in 5 mL of toluene) was added to the monomer/activator solution. After the desired time, an overpressure (15 psig) of ethylene was established. The third block was formed by discontinuing the ethylene feed and venting the headspace. ^Determined by GPC analysis of an aliquot withdrawn from the polymerizaton reaction. "Determined via GPC in 1,2,4- C₆H₃Cl₃ at 140 °C vs PS standards. ^Determined via DSC, 2^nd heating cycle.

Variations

The foregoing description of the invention has been presented describing certain operable and preferred embodiments. It is not intended that the invention should be so limited since variations and modifications thereof will be obvious to those skilled in the art, all of which are within the spirit and scope of the invention.

Claims

WHAT IS CLAIMED IS:

1. Pyridylamidohafhium catalyst precursor having the structure

where R¹ and R² are both hydrogen, or selected from the group of consisting OfC₁-C₅ alkyl, silyl, and combinations thereof, and optionally, R¹ and R² may be joined together in a ring structure narrowed to avoid prior art, where each of R³, R⁴, R⁵, R⁶, R⁷, R⁸, R⁹, R¹⁰, R¹¹, R¹², R¹³, R¹⁴ is independently selected from the group consisting of hydrogen, Ci-C₅ alkyl, silyl, and combinations thereof, and optionally, any combination of R³, R⁴, R⁵, R⁶, or R⁷, any combination of R⁸, R⁹, or R¹⁰, and any combination of R¹ ', R¹², R¹³, or R¹⁴ may be joined together in a ring structure, where each of R¹⁵ and R¹⁶ is independently selected from the group consisting of halide, Ci-C₅ linear or branched alkyl or benzyl, C]-C₂ alkoxy, or optionally R¹⁵ and

R , 16 may be joined together in a ring structure.

2. Pyridylamidohafhium catalyst precursor of claim 1 , where the precursor has C₃-symmetry

3. Pyridylamidohafhium catalyst precursor of claim 1 or 2, where the angle defined below (ZCNC) is larger than 114 degrees.

4. Pyridylamidohafhium catalyst precursor having the structure

or

where R¹⁷ and R²¹ are selected from H and methyl, where R¹⁸ and R²² are selected from isopropyl and tert-butyl, where R¹⁹ and R²³ are selected from H, isopropyl and tert-butyl and R²⁰ and R²⁴ are selected from C₁-C₄ linear or branched alkyl and benzyl.

5. The active species generated from the reaction of the compound of claim 1 to 4 and an activator.

6. The active species in claim 5 where an activator is B(C₆Fs)₃.

7. A diblock copolymer, triblock copolymer, or multiblock copolymer prepared with the active species of claim 5 or 6 comprising in polymerized form propylene and one or more copolymerizable comonomers other than propylene, said copolymer containing therein two or more segments or blocks differing in comonomer content, crystallinity, density, melting point or glass transition temperature.

8. A triblock copolymer of claim 7 where the end blocks are isotactic polypropylene and the midblock is a poly(ethylene-co-propylene).

9. A multiblock copolymer of claim 7 where the number of segments is not less than three and the end blocks are isotactic polypropylene.

10. A method for living polymerization of a C₂-C_2O alkene in a non-polar non- protic solvent in the presence of the active species of claim 5 or 6.

11. A diblock copolymer, triblock copolymer, or multiblock copolymer prepared using the active species of the second embodiment comprising in polymerized form 4- methyl-1-pentene and one or more copolymerizable comonomers other than 4- methyl-1-pentene, said copolymer containing therein two or more segments or blocks differing in comonomer content, crystallinity, density, melting point or glass transition temperature.

12. A triblock copolymer or a multiblock copolymer of claim 11 where the end blocks are isotactic poly(4-methyl-l-pentene) and poly(ethylene-co-4-methyl-l- pentene) is included as a midblock.