POLYMERIZATION OF FUNCTIONALIZED MONOMERS
WITH ZIEGLER-NATTA CATALYSTS
Field of the Invention
The invention relates to functionalized polyolefins and particularly to methods of polymerizing alpha-olefins containing functional groups.
Background of the Invention
The incorporation of functional groups onto poly(alpha-olefins) has been an area of long-standing interest as it represents a useful method for modifying the chemical and physical properties of poly(alpha- olefins). Commercially useful improvements in the adhesive, thermal, rheological, morphological, and mechanical properties of the polymer can be achieved by introducing functionality onto the polymer. In addition, polyolefin polymers containing functional
groups show improved affinity for dyes and printing agents and are more compatible with polar polymers.
The preparation of functionalized poly (alpha- olefins) has proven to be a difficult challenge. Poly(alpha-olefins) are typically prepared with Ziegler- Natta type catalysts. These catalysts are remarkable in their ability to polymerize unactivated olefins to yield a variety of stereoregular and stereorandom polymers. However, they have a major limitation as they are readily poisoned by monomers containing functional groups. Conventional catalysts based on Group 4 metal halides and alkylaluminum cocatalysts are intolerant to most types of monomers containing ethers, esters, amines, and carboxylic acids. Due to the interest in functionalized poly (alpha-olefins), extensive research has focused on developing processes to produce functionalized poly(alpha-olefins) despite the intolerance of the conventional catalysts to functional groups. Strategies include both post-polymerization functionali- zation processes and the direct polymerization of sterically hindered, functionalized monomers.
Post-polymerization functionalization techniques include free-radical grafting of unsaturated groups onto the polymer (Mukherjee et al., J. Macromol . Sci . Chem. , A19 (1983), p. 1069), polymer oxidation (Dasgupta, S., J. Appl . Polym. Sci . , 41 (1990), p. 233), anionic treatment of the polymer (Harada et al., Jpn Kokai Tokkyo Koho JP 62054713), and high energy radiation of the polymer (Stamm et al., J. Appl . Polym. Sci . , 7 (1963), p. 753). Some success has been achieved in this area as a wide variety of functionalized polymers have been synthesized and their properties studied. However, these methods are plagued with problems such as polymer degradation, polymer cross- linking, non-uniform incorporation of the functional
group onto the polymer, difficulty in scale-up and cost, particularly in the case of alpha-olefin polymers.
There have been numerous attempts to directly homopolymerize or copolymerize alpha-olefins containing functional groups using conventional Ziegler-Natta catalysts based on Group 4 metal halides and alkyl- aluminum cocatalysts. (The work in this area has been summarized elsewhere. See Datta, S., EPA 0 295 076 (1988) and references therein; Padwa, A.R., Prog. Polym. Sci ., 14 (1991), p. 811 and references therein; Purgett et al., J. Polym. Sci . , Part A: Polym. Chem. , 27 (1989), p. 2051 and references therein; Purgett, Ph.D. Thesis, University of Massachusetts, 1984 and references therein; Giannini et al., J. Polym. Sci . , Part C, 22 (1968), p. 157.) However, limited success has been achieved due to the serious loss in catalytic activity in the presence of functional groups such as amines, esters, amides, alkylhalides, and carboxylic acids. For homopolymerizations, less than 20 turnovers (turnover = mmol monomer/mmol catalyst) are generally observed. For copolymerizations, low (>5%) incorporation of the functionalized monomer is usually observed.
Several approaches have been taken to minimize the destructive interaction between the functional group and the Ziegler-Natta catalyst. These strategies include: (1) insulating the double bond from the heteroatom or functional group by incorporation of a spacer group such as one or more methylene units; (2) increasing the steric encumbrance about the functional group via the use of a protecting group; (3) precom- plexing the functional monomer with a Lewis acid such as an alkylaluminum compound; (4) using an organoborane reagent which is compatible with the catalyst mixture and is subsequently functionalized after polymerization (see Chung et al., Macromolecules , 23 (1990), p. 865 and references therein). Strategies (1) through (3) have
resulted in low catalyst activities, whereas strategy (4) suffers from the high cost and potential toxicity of boron containing polymers.
In light of these deficiencies, the need for an improved strategy for the polymerization of functional monomers and the copolymerization of functional monomers with alpha-olefins is apparent.
Summary of the Invention
It is an object of the invention to provide homogeneous catalysts systems for the homopolymerization of functionalized alpha-olefins to yield both stereoregular and stereorandom polyolefins.
It is another object of the invention to provide catalysts systems for the copolymerization of functionalized and unfunctionalized alpha-olefins to yield both stereoregular and stereorandom copolymers.
It is a further object of this invention to provide both stereoregular and stereorandom functionalized copolymers.
It is yet another object of the invention to provide both stereorandom and stereoregular functionalized polyolefins.
It is another object of the invention to provide chiral functionalized polymers.
It has now been discovered that the foregoing and other disadvantages of prior art olefin polymerization catalyst systems can be avoided, or at least reduced by, the application of aluminum-free "cationic" metallocene Ziegler-Natta catalysts for the polymerization of suitably protected functionalized monomers.
These "new generation" type catalysts include catalyst systems employing a cationic Group 4 metallocene and "compatible non-coordinating anions."
"New generation" Ziegler-Natta type catalysts also includes catalysts based on Group 4 metallocenes
and methylaluminoxane cocatalysts. These "new generation" catalysts are superior to the conventional catalysts for the polymerization of functionalized monomers and the copolymerization of functionalized monomers with alpha-olefins.
One aspect of the present invention is the choice of functional monomer to be polymerized with the new generation "cationic" metallocene catalysts. These monomers include olefins containing functional groups such as ethers, silyl ethers, carbazoles, tertiary phosphines, and tertiary amines.
The formed polymers include homopolymers of functionalized monomers as well as copolymers of functionalized monomers with ethylene and alpha-olefins. The formed polymers include both stereoregular (isotactic and syndiotactic) and stereorandom polymers. The functionalized monomers include nonconjugated dienes and alpha-olefins with amine, phosphine, carbazole, and silylether groups. Brief Description of the Drawings:
Figures 1A and 1B are C NMR spectra of syndiotactic poly (5-N,N-diisopropyl-1-pentene) and isotactic poly (5-N,N-diisopropyl-1-pentene), respectively.
Figure 2 is a C NMR spectrum of 1-hexene/5-
N,N-diisopropyl-1-pentene isotactic copolymer.
Description of the Preferred Embodiments:
The present invention is based, in part, on the discovery that certain homogeneous Ziegler-Natta catalysts can be used for the polymerization of functionalized alpha-olefins. These catalysts do not require highly Lewis acidic aluminum cocatalysts, in contrast to conventional Ziegler-Natta catalysts. The inventive catalysts comprise cationic Group 4 metallo-
cenes in the presence of preferably a "compatible non- coordinating anions." For this purpose "compatible non- coordinating anions" are those as described in EPA Nos. 277 003 and 277 004 filed January 27, 1988 by Turner et al. and EPA No. 427 697-A2 filed October 9, 1990 by Ewen et al. As stated on page 3 of EPA 227 003, a "compatible non-coordinating anion" means an anion which either does not coordinate with a cation or which is only weakly coordinated to said cation and thereby remaining sufficiently labile to be displaced by a neutral Lewis base. The recitation "compatible non-coordinating anion" specifically refers to an anion which when functioning as a stabilizing anion in the catalyst system of this invention does not transfer an anionic substituent or fragment thereof to said cation thereby forming a neutral four coordinate metallocene and a neutral boron by-product. Compatible anions are those which are not degraded to neutrality when the initially formed complex decomposes.
The inventive cationic metallocene catalysts are prepared by one of several known procedures as reported in EPA Nos. 277 003 and 277 004 filed January 27, 1988 by Turner et al.; EPA No. 427 697-A2 filed October 9, 1990 by Ewen et al.; Marks et al., J. Am. Chem. Soc. , 113 (1991), p. 3623; Chien et al., J. Am. Chem. Soc , 113 (1991), p. 8570; Bochman et al., Angew. Chem. Intl, Ed. Engl . , 7 (1990), p. 780; and Teuben et al., Organometallics , 11 (1992), p. 362 and references therein, all of which are incoporated herein. The inventive Group 4 metallocenes may be represented by the following formula:
(Ln)MX1X2
where (Ln) is (Cp')(Cp*) or Cp"-B-Cp and Cp' and Cp* are cyclopentadienyl radicals (C5R5) and Cp" and Cp** are cyclopentadienyl radicals (C5R4) substituted with R groups where R = hydrogen, alkyl, or aryl radicals,
where x1 and x2 are, independently, selected from the group comprising of hydride radicals, hydrocarbyl radicals, substituted-hydrocarbyl radicals, organometal- loid radicals, and the like, where B is a covalent bridging group, and where M is titanium zirconium, or hafnium.
Suitable reagents used to generate the active "cationic" metallocene (when combined to a Group 4 metal compound) is preferably (but not limited to) one of the following four types: (1) a tertiary ammonium salt R3NH+A-, where A is a compatible non-coordinating anion (counterion) as defined by Turner (EPA Nos. 277 003 and 277 004) ; (2) Ox+A- where Ox+ is a one electron oxidant and A- is a compatible non-coordinating anion (counterion) as defined by Turner (EPA Nos. 277 003 and 277
004); (3) a triaryl borane B(Ar)3 where Ar is C6F5 or
C6Hx(CF3)x-5, as described by Ewen (EPA No. 427 697); or
(4) a trityl salt Ph3C+A- as described by Chien et al.,
J. Am. Chem. Soc. , 113 (1991), p. 8570, where A- is a compatible non-coordinating anion (counterion) as defined by Turner (EPA Nos. 277 003 and 277 004).
The monomers that can be polymerized with the catalyst system include alpha-olefins containing silyl or trityl ethers, trialkyl, dialkylaryl, diarylalkyl or triaryl amines, or trialkyl, dialkylaryl, diarylalkyl or triarylphosphines and alkylcarbazoles.
It has also been found that polymerization of functionalized alpha-olefins can also be achieved with certain soluble Group 4 based metallocenes with methylaluminoxane co-catalysts. The metallocene/aluminoxane are described in German Patent Application Nos. 2,608,863 and 2,608,933; U.S. Patent 4,542,199, inventors Kaminsky et al., issued September 19, 1985; Ewen, J. Am. Chem. Soc , 106 (1984), p. 6355; Ewen et al., J. Am. Chem. Soc , 109 (1987) p. 6544; Ewen et al., J. Am. Chem. Soc , 110 (1988), p. 6255.; Kaminsky et
al., Angew. Chem . , Int . Ed . Eng. , 24 (1985), p. 507; Kaminsky et al., Makromol . Chem. , 190 (1989), p. 515; and Pino et al., J. Am. Chem. Soc , 109 (1987), p. 6189; all of which are incorporated herein.
The metallocene component has the general formula (Ln)MX1X2, which is the same as the Group 4 metal compounds described above. The aluminoxane component is either (i) a linear aluminoxane having the general formula Al2OR4 (Al (R)-O)n or (ii) a cyclic aluminoxane having the general formula (Al (R)-O)n+2, where n is a number from 4 to 20 and R is a methyl or ethyl radical.
The aluminoxane component is generally mixed with a metallocene component in a 100/1 to 10,000/1 molar ratio of aluminum to the Group 4 metal in suitable solvents such as toluene or heptane. It has been demonstrated that the aluminoxane catalysts can polymerize alpha-olefins containing silyether functional groups. (See Examples 12 and 16 herein.)
EXPERIMENTAL RESULTS
All of the examples described herein were carried out under nitrogen either in a glove box or using standard Schlenk techniques. Toluene was distilled under nitrogen from triisobutylaluminum. Methyl- aluminoxane (MAO) was obtained as a toluene solution (14.6% aluminum (w) ) from Sherex and was dried in vacuo prior to use. H, C, Attached Proton Test (APT) NMR experiments were carried out at room temperature on Varian Gemini 200, Gemini 300, and XL-400 spectrometers using CDC13 as the solvent. Analytical GPC data were obtained on Waters 10 A, 500 A, and Linear ultrastyragel columns employing a Waters 410 refractive index diffractometer with tetrahydrofuran as the mobil phase; molecular weights were calculated versus polystyrene standards. DSC (differential scanning calorimetry) measurements were obtained with a Perkin Elmer DSC 7
thermal analyzer at a heating rate of 10°C/minute from 30°C to 300°C. TGA (thermal gravimetric analysis) measurements were obtained with a Perkin Elmer TGA 7 instrument at a heating rate of 20°C/minute from 50°C to 700°C.
The compounds 4-TMS0-1, 6-heptadiene (TMSO = trimethylsiloxy), 4-TBDMSO-1,6-heptadiene (TBDMSO = tert-butyldimethylsiloxy), 4-TMSO-1-pentene, 4-TBDMSO-1- pentene, allyloxytrimethylsilane, allyloxy (tert-butyl- dimethylsilane) were prepared from 1,5-hexadiene-4-ol (Wiley), 4-pentene-1-ol (Wiley) and allylalcohol (Aldrich), respectively, according to literature methods (Chaudhary et al., Tet. Lett . , 2 (1979), p. 99). Diallylether, 5-bromo-1-pentene, diallylphenylamine, and diallylsulfide were obtained from Aldrich. 5-N,N-diisopropylamino-1-pentene was prepared according to a literature procedure (Giannini et al., J. Polym. Sci . , Part C, 22 (1968), p. 157). All monomers were >98% pure by GC analysis. Each monomer was distilled from CaH2 under nitrogen and degassed prior to use. Poly (vinylalcohol) was obtained from Aldrich (>99% hydrolyzed, MW = 85,000- 146,000). Anhydrous HCl was obtained from Matheson.
Cp*2Zr(CH3)2 (Cp*=pentamethylcyclopentadienyl) was prepared using a modified literature procedure (Bercaw et al., J. Am. Chem. Soc , 100 (1978), p. 3078), (EBTHI)ZrMe2 (EBTHI = ethylene-1, 2-bis (n5-4,5,6,7- tetrahydro-1-indenyl) was prepared from (EBTHI) ZrCl2 (Wild et al., J. Organomet. Chem. , 232 (1982), p. 233), in a similar manner as Cp+ 2Zr(CH3)2 via the addition of 2 equiv of MeLi to a toluene solution of (EBTHI) ZrCl2 at -78°C.
The reactions described herein were done at approximately 20°C or at -25°C in toluene. It is believed that polymerization in toluene occurs readily between -25°C to 100°C. Other suitable solvents include heptane, anisole, and dimethylaniline.
EXAMPLE 1
In the dry box, a 20 ml vial was loaded with 829 mg (1.1 ml, 4.89 mmol) of 5-N,N-diisopropylamino-l- pentene, 2 ml of a Cp2Zr(CH3)2/ toluene solution (8 mg/ml, 0.041 mmol added), and 0.90 ml of toluene. The vial was placed in a toluene bath (20°C) and equipped with a thermometer and stir bar. The reaction was initiated by adding 1.0 ml of a B(C6F5)3/toluene solution (10.12 mg/ml, 0.020 mmol added). The solution slowly turned yellow (over 10 minutes), then green-yellow at 25 minutes. Small aliquots (0.1 ml - 0.5 ml) were removed from the reaction mixture at reaction times of 0 minute and 30 minutes. Each aliquot was immediately quenched in a vial containing alumina and analyzed by GC. The reaction was quenched after 60 minutes via the addition of acetone which caused a color change from green to yellow. The following data was obtained:
Aliquot Time Conversion Turnovers Average Activity
(min) (%) (mmol monomer (turnover/h)
/mmol Zr)
1 0 0 0 0
2 30 55 66 132
3 60 76 91 91
The volatiles were removed in vacuo to leave a yellow oil. The catalyst residues were removed from the polymer by dissolving the crude product in hexanes and filtering through a plug of alumina. A light yellow solution was collected. The hexane was removed under vacuum to leave a light yellow oil which was analyzed by 1H (endgroup analysis indicates Mn = 2900) and 13C NMR.
EXAMPLE 2
A 50 ml schlenk tube was loaded with 12 mg (0.023) of B(C6F5)3. An addition funnel was loaded with 842 mg (4.97 mmol) of 5-N,N-diisopropylamino-1-pentene,
17 mg of Cp2Zr(CH3)2 and 3.9 ml of toluene and the addition funnel attached to the 50 ml schlenk. The system was sealed, removed from the dry box, and cooled to -78 °C in a dry ice/acetone bath. After approximately 10 minutes, the solution was added to the B(C6F5)3. The reaction vessel was moved to a dry ice/CCl4 bath (-25°C). The solution slowly turned yellow after approximately 30 minutes. The reaction was quenched with acetone after stirring at -25°C for 2 hours. GC analysis of the quenched reaction mixture indicated 68% conversion. The solvents were removed under vacuum to leave a sticky solid (mass = 590 mg, 66%). The crude product was dissolved in hexanes, filtered through a plug of alumina and dried under vacuum to afford a light yellow wax. Polymer characterization by NMR (CDCl3) indicated a highly syndiotactic microstructure (Fig. 1A) : 1H (400 MHz): δ 4.65 (d, methylene endgroup, endgroup analysis indicates Mn = 8800), 2.92 (m, 2H), 2.25 (m, 2H), 1.50-0.80 (m, 19H); 13C (100 MHz): δ 48.3 (C6), [46.0, 45.8 (C5)], 41.1-40.1 (C1 ) , 32.2-31.9 (C2), 31.9-31.1 (C4), 28.5-26.6 (C3), 20.7 (C7).
EXAMPLE 3
In a similar fashion as described in Example 1, 845 mg (1.1 ml, 4.99 mmol) of 5-N,N-diisopropylamino- 1-pentene, 2 ml of a EBTHIZr (CH3)2/toluene solution (8 mg/ml, 0.041 mmol added), 1.0 ml of a B(C6F5)3/toluene solution (10.12 mg/ml, 0.020 mmol added) and 0.90 ml of toluene were reacted at 20°C. The solution turned light yellow over 10 minutes. GC analysis indicated 0% conversion. An additional 6 mg portion of EBTHIZr (CH3)2 and 4 mg of B(C6F5)3 was added. The reaction was quenched
after stirring for another 60 minutes via the addition of acetone. GC analysis indicated 72% conversion. The polymer was isolated in a similar fashion as described in Example 1 and was obtained as a light yellow, sticky wax. Polymer characterization by NMR (CDCl3) indicates a highly isotactic microstructure (Fig. 1B) : H (400 MHz): δ 4.65 (d, methylene endgroup, endgroup analysis indicates Mn = 5400), 2.92 (m, 2H), 2.25 (m, 2H), 1.50- 0.80 (m, 19H); 13C (100 MHz): δ 48.4 (C6), 45.9 (C5), 40.0 (C1), 32.4 (C4 and C2), 28.9 (C3), 20.73 (C7). Anal. (C11H23N) C, H, N.
EXAMPLE 4
In a similar fashion as described in Example 1, 910 mg (4.94 mmol) of 4-TMSO-1, 6-heptadiene, 1.55 ml of toluene, 0.25 ml of a B(C6F5)3/toluene solution (10.12 mg/ml, 0.0049 mmol added) and 2 ml of a Cp*2Zr(CH3)2/ toluene solution (2 mg/ml, 0.010 mmol added) were reacted at 20°C. The reaction was monitored by GC and the following data was obtained:
Aliquot Time Conversion Turnovers Averaqe Activity
(min) (%) (mmol monomer (turnover/h)
/mmol Zr)
0 0 0 0 0 1 10 22 106 640 2 15 37 180 720 3 30 59 282 564
After 1 hour, the reaction was exposed to air the product was isolated. A colorless, viscous oil was obtained (mass = 450 mg, 51%). The product was analyzed by 1H and 13C NMR which indicate complete cyclization of monomer. Polymer characterization: GPC (Mw/Mn = 1300/300). NMR (CDCl3) : 1H (400 MHz): δ 4.68 (m, methylene endgroup, endgroup analysis indicates Mm = 920), [4.10 (s), 3.98 (s), 3.72 (s), and 3.55 (m); 1H],
2.45-0.70 (m, 9.5H), 0.50 - 0.30 (m, 0.5H), 0.08 (s, 9H); 13C (100 MHz), δ [146.0 and 109.0, methylene endgroups], [71.1(m) and 66.9 (m), C-O], 45.2-40.0, 39.0-32.2, 30.0, 28.2-27.5, [24.2 and 20.0 cis- and trans of C5 of the 1-trimethylsiloxy-3- (polymer) cyclohexane endgroup]. Partial GC/MS data of the low molecular weight oligomers (cyclized monomer and dimer): 4-(Trimethylsiloxy)-methylenecyclohexane: M+ = 184(0.17), M+-·CH3 = 169(5.6), 129(77), - SiMe3 = 73(100).
M+ = 368 ( 2 . 7 ) , M+- · CH3 = 353 ( 2 . 3 ) , 224 ( 14 ) , 223 ( 66 ) , · SiMe3 = 73 ( 100 ) .
EXAMPLE 5
In a similar fashion as described in Example
2, 956 mg (1.1 ml, 5.18 mmol) of 4-TMSO-1,6-heptadiene, 1.0 ml of a Cp*2Zr(CH3)2/toluene solution (8 mg/ml, 0.020 mmol added), 0.50 ml of a B(C6F5)3/toluene solution
(10.12 mg/ml, 0.010 mmol) and 2.40 ml of toluene were reacted at -25°C. The reaction was quenched with acetone after stirring at -25°C for 2 hours. GC analysis of the quenched reaction mixture indicated 98% conversion. The solvents were removed under vacuum to leave a glassy, yellow solid (mass = 970 mg). The catalyst residues were removed from the polymer in a similar fashion as described in Example 1 to obtain white powder which was analyzed by GPC (Mw/Mn = 13,534/5013), H (complete cyclization, endgroup analysis indicated Mn = 8100) and 13C NMR.
EXAMPLE 6
In a similar fashion as described in Example 1, 16 mg (0.042 mmol) of EBTHIZrMe2, 1.134 g (5.0 mmol)
of 4-TBDMSO-1,6-heptadiene, 1.0 ml of a B (C6F5)3/toluene solution (10.6 mg/ml, 0.021 mmol added) and 2.6 ml of toluene were reacted at 22°C. Upon mixing, the solution turned yellow and a slight exotherm was detected (22- 26°C). The reaction was monitored by GC and the following data was obtained:
Aliquot Time Conversion Turnovers Average Activity
(min) (%) (mmol monomer (turnover/h)
/mmol Zr)
0 0 0 0 0 1 2 48 58 1730 2 5 52 62 750 3 11 81 97 530 4 25 93 112 267 After 1 hour, the reaction was quenched with acetone and the solvents were removed under vacuum. A sticky solid was obtained (mass = 850 mg, 75%). The product was washed with acetone (3 x 15 ml) and redried under vacuum to yield a glassy solid. This solid was taken up in hexanes, filtered through a plug of alumina and redried under vacuum to afford a white powder. Polymer characterization: GPC: Mw/Mn = 4122/770. NMR (DMSO-d6) : 1H (400 MHz): -5 [5.80 and 5.10, uncyclized olefins, calculated % cyclization = 88%], 4.65 (m, methylene endgroup, endgroup analysis indicates Mn = 2800), [4.20 (s), 4.05 (s), 3.98 (s), 3.71 (s) and 3.53 (s); 1H], 2.10-0.70 (m, 18.5H), 0.55 - 0.30 (m, 0.5H), 0.03 (d, 6H); 13C (100 MHz): δ [71.8 and 67.9, C-O], 45.7-40.0, 38-36, 34.2-32, 30-29, 28, 26, 18.1, -4.5. Anal. (C13H26OSi) C, H.
EXAMPLE 7
In a similar fashion as described in Example 1, 996 mg (1.2 ml, 4.96 mmol) of 5-TBDMSO-1-pentene, 1.0 ml of a B(C6F5)3/toluene solution (5.4 mg/ml, 0.011 mmol
added), 8 mg (0.020) of Cp2Zr(CH3)2 and 2.8 ml of toluene were reacted at -25°C for 2 hours. The reaction was quenched with acetone; GC analysis indicated 77% conversion of monomer. The solvents were removed under vacuum to leave a sticky solid (mass = 901 mg). The polymer was isolated in the usual manner to obtain a waxy solid. Polymer characterization: GPC: MH/Mn = 36,000/12,000. NMR (CDCl3); 1H (400 MHz): δ 4.65 (d, methylene endgroup, endgroup analysis indicates Mn = 10,000), 3.60 (m, 2H), 1.70-0.70 (m, 16H), 0.10 (s, 6H); 13C (100 MHz): δ 63.7 (C5), 40.1 (C1), 31.6 (C2), [29.6, 29.5 and 29.4 (C3 and C4)], 26.0 (C8), 18.3 (C7), -5.2 (C6). Anal. (C11H24OSi) C, H.
Examples 1-7 are summarized in Table 1 and compared to 1-hexene.
a Conditions: A toluene solution of B(C6F5)3 was added to a toluene solution of metallocene and 5.0 mmol monomer, total solutio volume = 5 ml. Reactions were monitored by GC. b Temperature =± 3 °C. cTurnovers = mmol monomer consumed per mmol metallocene. d Determined by GPC analysis. GPC analyses of the polyamines were irreproducible. - Estimated from 1Η NMR endgroup analysis. Cp* = pentamethylcyclopentadienyl, EBTHI = ethylene-1,2-bis(n5-4,5,6,7-tetrahydro-l-indenyl), TMS = trimethylsilyl, TBDMS = tert-butyldimethylsilyl.
EXAMPLE 8
In a 20 ml vial, 3.348 g (19.77 mmol) of 5-
N,N-diisopropylamino-1-pentene, 210 mg (1.06 mmol) of triisobutylaluminum, 5.0 ml of toluene, 20 mg (0.053 mmol) of rac-EBIZrMe2, and 14 mg (0.027 mmol) of B(C6F5)3 were reacted at 20°C for 22 hours. GC analysis indicated 48% conversion. The polymer was isolated in the usual manner to obtain 1.59 g of a white, tacky powder which was analyzed by NMR (endgroup analysis indicated Mn >25,000).
EXAMPLE 9
A 20 ml vial was loaded with a stir bar, thermometer, 5 ml of toluene, 838 mg of 4-TMSO-1,6- heptadiene, and 7 mg of Cp*2Hf(CH3)2. An 8 mg portion of [N,N-dimethylanilinium] [B(C6F5)4] was added. After approximately 1 minute, the solution turned orange and an exotherm was detected (20-52°C). An aliquot was taken after 10 minutes; GC analysis indicated 93% conversion. The reaction was quenched with acetone and the polymer isolated in the usual manner and analyzed by NMR (complete cyclization) and GPC: MH/Mn = 1100/500.
EXAMPLE 10
A 50 ml schlenk was loaded with a stir bar and
36 mg of [N,N-dimethylanilinium] [B(C6F5)4]. An addition arm was loaded with 2.49 g of 4-TMSO-1,6-heptadiene and 21 mg of Cp*2Hf(CH3)2. The arm was attached to the shlenk tube and the system sealed. The solution was cooled to -25°C in a dry ice/CCl4 bath. After 30 minutes, the solution was added to the [N,N-dimethylanilinium] [B(C6F5)4] and the mixture was allowed to stir at -25°C. The solution turned yellow and became quite viscous after 25 minutes. The reaction was quenched after 2 hours via the addition of 50 ml of acetone. The polymer was worked up in the usual manner. A clear,
tough plastic was obtained (mass = 952 mg, 38% yield). Polymer characterization: GPC: Mw/Mn = 46,000/15,000. NMR(CDCl3) : 1H (400 MHz): Complete cyclization was observed: δ [4.02 (s), 3.70 (s) and 3.50 (s); 1H], 2.00-0.70 (m, 9.5H), 0.50-0.30 (m, 0.5H), 0.08 (s, 9H); 13C (100 MHz): δ [71.1 and 67.2, C-O], 44.2-40.4, 39.9- 39.1, 37.5, 37.1, 32.5, 30.0, 29.3, 28.2, 0.3. IR (neat): 2900 (C-H), 1100 (C-O). Anal. (C10H20OSi) C, H.
EXAMPLE 11
In a similar fashion as described in Example
10, 30 mg of [N,N-dimethylanilinium] [B(C6F5)4], 2.482 g of 4-TMSO-1,6-heptadiene, and 21 mg of Cp2Hf(CH3)2 were reacted at -25°C for 1.5 h. The reaction was quenched with acetone and the polymer washed with 3 x 15 ml of acetone. The polymer was dried under vacuum to afford a tough plastic (mass = 1.0 g, 46%). Polymer characterization: GPC: Mw/Mn = 95,000/28,000.
EXAMPLE 12
A 20 ml vial was loaded with a stir bar, 5 ml of toluene, 882 mg of 4-TMSO-1,6-heptadiene, and 5 mg
(0.013 mmol) of Cp2Zr(CH3)2 and 320 mg of methylaluminoxane (5.52 mmol Al). After stirring for 1 hour, the reaction was quenched via the addition of 4 ml of methanol. GC analysis indicated 79% conversion. The polymer was isolated in the usual manner to afford 530 mg (60%) of a thick oil which was characterized by H and C NMR (the spectra was similar to that produced in Example 6), and GPC: Mw/Mn = 1600/450.
EXAMPLE 13
A 20 ml vial was loaded with 10 mg of
Cp*2Zr(CH3)2, 670 mg of 4,4-bis (TBDMSOCH2)-1,6-heptadiene, and 1 ml of toluene. A 4 mg portion of B(C6F5)3 was added. The solution turned dark orange. After stirring
for 10 hours, the reaction was quenched with acetone. GC analysis indicated approximately 75% conversion. Polymer characterization: GPC: Mw/Mn = 970/240
EXAMPLE 14
A 20 ml schlenk was loaded with 12 mg of
EBTHIZr (CH3)2, 910 mg of 4,4-bis (TBDMSOCH2)-1,6- heptadiene, and 5 ml of toluene. An 8 mg portion of B(C6F5)3 was added. The solution immediately turned yellow and was allowed to stir for 2.5 hours; GC analysis indicated 17% conversion. An additional 7 mg portion of EBTHIZr (CH3)2 and 4 mg of B(C6F5)3 was added and the solution turned dark orange. The solution was stirred for 3 hours; GC analysis indicated 73% conversion. The polymer was isolated in the usual manner and was characterized by 1H and 13C NMR and GPC analysis: Mw/Mn = 1600/540.
EXAMPLE 15
A 20 ml vial was loaded with 5 ml of toluene, 6 mg of Cp2Zr(CH3)2 and 823 mg (3.39 mmol) of 11- trimethylsiloxy-1-undecene. A 13 mg (0.016 mmol) portion of [N,N-dimethylanilinium] [B(C6F5)4] was added. Immediately, the solution turned yellow. The reaction was stirred for 30 min and then quenched with methanol; GC analysis indicated 54% conversion. EXAMPLE 16
A 20 ml vial was loaded with 5 ml of toluene, 6 mg of Cp2Zr(CH3)2 and 823 mg (3.39 mmol) of 11- trimethylsiloxy-1-undecene. A 665 mg (11.5 mmol) portion of methylaluminoxane was added. Immediately, the solution turned yellow. The reaction was stirred for 40 minutes and then quenched with methanol; GC analysis indicated 29% conversion.
EXAMPLE 17
A 20 ml vial was loaded with 848 mg of 1,5- hexadiene-3-OTBDMS, 5 ml of toluene, and 18 mg of
Cp2Zr(CH3)2. A 36 mg portion of [N,N-dimethylanilinium] [B(C6F5)4] was added. Immediately, the solution turned orange. The reaction was stirred overnight and then quenched with acetone; GC analysis indicated 32% conversion. The polymer was isolated in the usual manner to obtain a rubbery solid. The solid was characterized by GPC: MH/Mn = 62,000/29,000 and 1H and
13C NMR.
EXAMPLE 18
A 20 ml vial was loaded with 1.002 g (3.93 mmol) of 5-diphenylphosphino-1-pentene, 4 ml of toluene and 29 mg (0.074 mmol) of Cp2Zr(CH3)2. A 20 mg portion of B(C6F5)3 was added. Immediately, the solution turned yellow. After 15 min, the solution turned orange. An aliquot was taken after 1.25 hours; GC analysis indicated 50% conversion. The reaction was quenched after 3 hours by exposing the solution to air; GC analysis indicated 88% conversion. The solvent was removed under vacuum to leave a viscous oil which was analyzed by H (endgroup analysis indicates Mn = 2000) and 13C NMR. EXAMPLE 19
In a similar fashion as described in Example 1, 1.224 g (5.20 mmol) of N-(1-pentene-4-yl) carbazole, 4 ml of toluene, 8 mg (0.020 mmol) of Cp 2ZrMe2 and 9 mg (0.018 mmol) of B(C6F5)3 were reacted at 20°C for 1.5 hours. An exotherm was detected (20-37°C). The reaction was quenched with methanol and the solvents were removed in vacuo. The residue was washed with 2 x 30 ml of hexanes and 2 x 30 ml of methanol and the
product dried to obtain 900 mg of an off-white solid. NMR analysis indicated a DP = 8.
Post-Polymerization Functionalization
EXAMPLE 20
Removal of trimethylsilane from poly(methylene-3,5-(1-TMSO)-cyclohexane) to afford poly(methylene-3,5-cyclohexanol). 719 mg of poly (methylene-3,5-(1-trimethylsiloxy)cyclohexane) (prepared via the reaction of Cp*2Hf(CH3)2 and [N,N- dimethylanilinium] [B(C6F5)4] in neat monomer at -25°C, Mw/Mn = 46,000/15,000) was dissolved in 20 ml of hexanes. Concentrated HCl was added dropwise (approximately 1 ml). Immediately, a white solid precipitated from solution. The solution was stirred for 30 minutes and the solvents were removed in vacuo to leave a white powder which was soluble in DMSO, DMF, and pyridine. The sample was thoroughly dried in vacuo overnight to yield 437 mg (98% (w) ) of a white powder. The solid was analyzed by 1H and 13C NMR (DMSO-d6) (see below) which indicated the presence of an -OH group and the absence of TMS. The IR (nujol) spectrum exhibited a large -OH stretch which was absent in the silyl-protected material. Polymer characterization: NMR (DMSO-d6) : 1H (400 MHz): δ 4.30 (broad, OH), [3.90 (s), 3.55 (s) and 3.37 (s); 1H], 2.0-0.20 (m, 11H); 13C (100 MHz): δ [68.7 and 64.8 (C-O)], 45.0-44.0, 44.0-42.0, 40.5-38.0, 33.0, 32.0, 29.7, 28.2, 27.2. IR (nujol): 3300 (broad, OH), 2900 (C-H), 1000 (C-O). Anal. (C7H12O) C, H.
EXAMPLE 21
Reaction of poly (5-N,N-diisopropyl-1-pentene) with HCl to afford poly (5-N,N-diisopropyl-1-pentene) HCl. 173 mg of poly (5-N,N-diisopropyl-1-pentene)
(prepared via the reaction of Cp*2Zr(CH3)2 and B(C6F5)3 at
-25°C) was dissolved in 15 ml of toluene under N2. Anhydrous HCl was bubbled through the solution for 2-3 minutes. A white solid precipitated from solution. The toluene was removed under vacuum and the solid washed with hexanes (2 x 10 ml). The solid was dried in vacuo . An off-white, hygroscopic solid was obtained (203 mg, 97% (w) ) which was soluble in water, chloroform and methanol. Analysis by H and C NMR (see below) indicated the presence of an N-HCl group. The IR spectrum exhibited a broad peak from 2700-2400 cm-1 which is indicative of a tertiary ammonium chloride. Polymer characterization: 1H (CDCl3, 200 MHz): δ 10.0 (broad, NH), 4.10-0.40 (broad); 13C ,(50 MHz) : δ 54.4, 48 (broad), 39 (broad), 32 (broad), 24 (broad), 18.4, 17.0. IR (nujol): 3500 (broad), 2900 (C-H), 2700-2400 (broad, N·HCl). Anal. (C11H24NCl) C, H, N, Cl.
Copolymerizations
EXAMPLE 22
In the dry box, a 20 ml vial was loaded with 832 mg (4.91 mmol) of 5-N,N-diisopropylaminol-pentene, 429 mg (5.10 mmol) of 1-hexene, 3.25 ml of toluene, 68 mg of triisobutylaluminum and stirred for 30 minutes. rac-EBIZrMe2 (6 mg, 0.016 mmol) and B(C6F5)3 (8 mg, 0.016 mmol) were added. The solution immediately turned dark brown and an exotherm was detected (20-28°C). The reaction was quenched after 65 minutes and worked up in the usual manner to obtain 584 mg (46%) of a colorless, sticky solid. The polymer was analyzed by 1H and 13C NMR which indicated an isotactic copolymer was produced amine/hexene = 58%/42%). The C NMR spectrum is shown in Fig. 3. The copolymer was treated with a methanol/ HCl solution for 20 minutes and then dried in vacuo. A glassy solid was obtained which was completely soluble
in methanol and insoluble in hexanes which indicates that no homopolymer of 1-hexene is present.
It is to be understood that while the invention has been described above in conjunction with the preferred specific embodiments, the description and examples are intended to illustrate and not limit the scope of the invention, which is defined by the scope of the appended claims.