Propylene-based elastomer

Abstract

Provided is a propylene-based elastomer having high tacticity and excellent mechanical properties. The propylene-based elastomer includes 50% by weight or more of a propylene-based repeating unit, and satisfies a particular relationship between an ethylene content and tacticity.

Claims

1. A propylene-based elastomer comprising 50% by weight or more of a propylene-based repeating unit, and a residual amount of an olefin-based repeating unit comprising ethylene, wherein an ethylene content x (% by weight) and triad tacticity y (%) satisfy a relationship of y≧−2.27x+97.0, and wherein the olefin-based repeating unit further comprises alpha-olefin having 4 or more carbon atoms, and the triad tacticity y (%) is 50 to 80.

2. A propylene-based elastomer comprising 50% by weight or more of a propylene-based repeating unit, and a residual amount of an olefin-based repeating unit comprising ethylene, wherein an ethylene content x (% by weight) and triad tacticity y (%) satisfy a relationship of y≧−2.27x+97.0, and wherein the olefin-based repeating unit further comprises alpha-olefin having 4 or more carbon atoms, and the relationship is satisfied in the entire ethylene content range of 10 to 20% by weight.

3. The propylene-based elastomer of claim 1, wherein the propylene-based elastomer has a density of 0.860 to 0.890 g/cm.sup.3.

4. The propylene-based elastomer of claim 2, wherein the propylene-based elastomer has a density of 0.860 to 0.890 g/cm.sup.3.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1 is a graph showing a relationship between ethylene content and triad tacticity in propylene-based elastomers of example and comparative example.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(2) The present invention will be explained in more detail in the following Examples. However, the following Examples are only for exemplifying the invention and the invention is not limited to the following Examples.

(3) In the following Examples, the term “overnight” or “through the night” refers to about 12 to 16 hrs, and “room temperature” refers to 20 to 30° C. Organic reagents and solvents used were purchased from Aldrich and Merck, and used after purification by a standard method. In every steps of synthesis, experimental reproducibility was enhanced by blocking the contact with air and moisture. To confirm structures of the produced compounds, a 600 MHz nuclear magnetic resonance (NMR) spectrometer was used to obtain spectra.

Preparation Example: Synthesis of Ligand Compound and Transition Metal Compound

Preparation Example 1

Preparation Example 1-1: Synthesis of 1-(2-methyl-1H-inden-4-yl)-1,2,3,4-tetrahydroquinole

(4) To a 500 ml 2-neck Schlenk flask, 4-bromo-2-methyl-1H-indene (15.7 g, 75.63 mmol), 1,2,3,4-tetrahydroquinone (11.08 g, 83.19 mmol), LiOtBu (18.16 g, 226.89 mmol), Pd(P(tBu).sub.3).sub.2 (0.77 g, 1.5 mmol) were added, and the starting materials were dissolved by adding 252 mL of dry toluene, followed by stirring overnight in an oil bath at 110° C. The solution was cooled to room temperature, and then the reaction was terminated by adding 151 mL of deionized water thereto.

(5) After separating an organic layer therefrom, an aqueous layer was extracted twice with 50 mL of dichloromethane (DCM). The organic layer was collected and dried over Na.sub.2SO.sub.4, and filtered, distilled, and dried under vacuum at 60° C. overnight to obtain an orange colored compound (15.8 g, quantitative yield compared to 4-bromo-2-methyl-1H-indene, 80% yield compared to the starting material).

(6) .sup.1H-NMR (CDCl.sub.3): δ7.30-7.20 (m, 3H in isomers), 7.15-7.10 (d, J=7.5 Hz, 2H in isomers), 7.15-7.10 (d, J=8.0 Hz, 1H in isomers), 7.10-7.05 (d, J=8.0 Hz, 1H in isomers), 7.05-7.00 (d, J=7.5 Hz, 3H in isomers), 7.00-6.95 (d, J=7.5 Hz, 2H in isomers), 6.90-6.80 (t, J=7.5 Hz, 3H in isomers), 6.65-6.58 (m, 3H in isomers), 6.48 (s, 2H in isomers), 6.33 (s, 1H in isomers), 6.30-6.25 (d, J=8.0 Hz, 1H in isomers), 6.25-6.22 (d, J=8.0 Hz, 2H in isomers), 3.62-3.59 (t, J=5.5 Hz, 6H in 2-quinolinyl of isomers), 3.33 (s, 2H in 1H-indene of isomers), 3.10 (s, 3H in 1H-indene of isomers), 3.00-2.85 (m, 6H in 4-quinolinyl of isomers), 2.22-2.00 (m, 14H in 3H-quinolinyl and 2-Me of isomers)

Preparation Example 1-2: Synthesis of Bis(4-(3,4-dihydroquinolin-1(2H)-yl)-2-methyl-1H-inden-1-yl)-dimethyl silane

(7) To a 500 ml Schlenk flask, 1-(2-methyl-1H-inden-4-yl)-1,2,3,4-tetrahydroquinole (15.8 g, 60.5 mmol) was added, and the starting material was dissolved by adding 300 mL of dry diethyl ether, and then n-BuLi (2.5 M in n-Hx) (26.6 mL) was added thereto at −78° C., followed by stirring overnight at room temperature. Then, the mixture was filtered by using a glass frit (G4). The remaining solid on the glass frit was dried under vacuum to obtain a lithiated product (14.4 g, 89% yield) as a while solid. The lithiated product (14.2 g, 53.1 mmol) was put in a 500 mL Schlenk flask in a glove box and 152 mL of dry toluene and 7.6 mL of THF were added thereto for dissolving the same. After lowering the temperature to −30° C., Me.sub.2SiCl.sub.2 (3.2 mL, 26.6 mmol) was added thereto and the mixture was stirred at room temperature for a day. Thereafter, the mixture was stirred for 5 hrs in an oil bath at 140° C. After the mixture was cooled to room temperature, the reaction was terminated by adding 50 ml of deionized water.

(8) After separating an organic layer therefrom, an aqueous layer was extracted twice with 50 mL of dichloromethane (DCM). The organic layer was collected and dried over K.sub.2CO.sub.3 and filtered, distilled, and dried under vacuum at 60° C. overnight to obtain a brownish white solid ligand compound (15.8 g, quantitative yield compared to lithiated product, 89% yield compared to the starting material). As the result of .sup.1H-NMR analysis, the ratio of rac:meso was about 1:1.

(9) .sup.1H-NMR (CDCl.sub.3): δ 7.40 (d, J=7.5 Hz, 2H, 7,7′-H in indenyl of rac-isomer), 7.25 (d, J=7.5 Hz, 2H, 7,7′-H in indenyl of meso-isomer), 7.15 (t, J=7.5 Hz, 2H, 6,6′-H in indenyl of rac-isomer), 7.12 (t, J=8.0 Hz, 2H, 6,6′-H in indenyl of meso-isomer), 7.10 (d, J=7.5 Hz, 2H, 5,5′-H in quinolinyl of rac-isomer), 7.08 (d, J=7.5 Hz, 2H, 5,5′-H in quinolinyl of meso-isomer), 7.02 (dd, J.sub.1=7.0 Hz, J.sub.2=1.0 Hz, 4H, 5,5′-H in indenyl of rac- and meso-isomers), 6.85-6.81 (m, 4H, 7,7′-H in quinolinyl of rac- and meso-isomers), 6.60 (td, J.sub.1=7.5 Hz, J.sub.2=1.0 Hz, 4H, 6,6′-H in quinolinyl of rac- and meso-isomers), 6.46 (s, 4H, 3,3′-H in indenyl of rac- and meso-isomers), 6.26 (d, J=8.0 Hz, 4H, 8,8′-H in quinolinyl of rac- and meso-isomers), 3.81 (s, 2H, 1,1′-H in indenyl of rac-isomer), 3.79 (s, 2H, 1,1′-H in indenyl of meso-isomer), 3.69-3.57 (m, 8H, 2,2′-H in quinolinyl of rac- and meso-isomers), 2.92 (t, J=6.0 Hz, 8H, 4,4′-H in quinolinyl of rac- and meso-isomers), 2.21 (d, J=0.5 Hz, 6H, 2,2′-Me in meso-isomer), 2.13 (d, J=1.0 Hz, 6H, 2,2′-Me in rac-isomer), 2.13-2.08 (m, 8H, 3,3′-H in quinolinyl of rac- and meso-isomers), −0.27 (s, 3H, SiMe of meso-isomer), −0.29 (s, 6H, SiMe.sub.2 of rac-isomer), −0.30 (s, 3H, SiMe′-of meso-isomer)

Preparation Example 1-3: Synthesis of rac-dimethylsilylene-bis(4-(3,4-dihydroquinolin-1(2H)-yl)-2-methyl-indenyl) zirconium dichloride

(10) To a 500 ml Schlenk flask, 10.4 g (18 mmol, rac:meso=1:1) of bis(4-(3,4-dihydroquinolin-1(2H)-yl)-2-methyl-1H-inden-1-yl)-dimethyl silane was added, and the starting material was dissolved by adding 285 mL of dry toluene, and then 14.4 mL of n-BuLi (2.5 M in n-Hx) was added thereto at −78° C., followed by stirring for 5 hrs at room temperature. The mixture was cooled to −78° C., and transferred to a Schlenk flask, in which 4.2 g of ZrCl.sub.4 solution (18 mmol in 60 mL toluene) of −78° C. was put in advance, by using a cannula, followed by stirring at room temperature overnight. After the reaction was terminated, the product was filtered with a glass frit (G4) on which celite spread. The remaining solid on the glass frit was washed three times with about 5 mL of dry toluene. The toluene solution was dried under vacuum to obtain a red colored solid. The remaining solid on the glass frit was dissolved out by using dichloromethane (DCM). A red colored solid was obtained by drying the DCM filtrate under vacuum. As the result of .sup.1H-NMR analysis, both of two solids were Zr complex of rac:meso=1:1. This crude product was collected and stored in the oil bath of 45° C., and 50 mL of dry toluene was added thereto with stirring for dissolving the crude product. The solution was stored in a freezer of −30° C. for 3 days for recrystallization. The obtained red solid was filtered with a glass frit (G4) and washed twice with 5 mL of dry n-hexane, and dried under vacuum to obtain 1.3 g (1.9 mmol, 10.4% yield) of the final product of racemic body.

(11) .sup.1H-NMR (Tol-d.sub.3): δ 7.19 (d, J=8.5 Hz, 2H, 7,7′-H in indenyl), 7.02 (d, J=7.5 Hz, 2H, 5,5′-H in quinolinyl), 6.92 (d, J=7.5 Hz, 2H, 5,5′-H in indenyl), 6.85-6.82 (m, 2H, 7,7′-H in quinolinyl), 6.76 (dd, J.sub.1=8.5 Hz, J.sub.2=7.5 Hz, 2H, 6,6′-H in indenyl), 6.70-6.68 (m, 2H, 6,6′-H in quinolinyl), 6.67 (s, 2H, 3,3′-H in indenyl), 6.54 (d, J=8.5 Hz, 2H, 8,8′-H in quinolinyl), 3.85-3.69 (m, 4H, 2,2′-H in quinolinyl), 2.65-2.54 (m, 4H, 4,4′-H in quinolinyl), 1.95 (s, 6H, 2,2′-Me), 1.90-1.70 (m, 4H, 3,3′-H in quinolinyl), 0.84 (s, 6H, SiMe.sub.2)

Preparation Example 2

Synthesis of rac-dimethylsilylene-bis(4-(3,4-dihydroquinolin-1(2H)-yl)-2-methyl-indenyl)hafnium dichloride

(12) To a 250 ml Schlenk flask, 3 g (5.2 mmol, rac:meso=1:1) of bis(4-(3,4-dihydroquinolin-1(2H)-yl)-2-methyl-1H-inden-1-yl)-dimethyl silane prepared in Preparation Example 1-2 was added, and the starting material was dissolved by adding 85 mL of dry toluene, and then 4.4 mL of n-BuLi (2.5 M in n-Hx) was added thereto at −78° C., followed by stirring for 5 hrs at room temperature. The mixture was cooled to −78° C., and transferred to a Schlenk flask, in which 1.7 g of HfCl.sub.4 solution (5.2 mmol in 20 mL toluene) of −78° C. was put in advance, by using a cannula, followed by stirring at room temperature overnight. After the reaction was terminated, the product was filtered with a glass frit (G4) on which celite spread. The remaining solid on the glass frit was washed three times with about 3 mL of dry toluene. The toluene solution was dried under vacuum to obtain a red colored solid. The remaining solid on the glass frit was dissolved out by using dichloromethane (DCM). A red colored solid was obtained by drying the DCM filtrate under vacuum. As the result of .sup.1H-NMR analysis, both of two solids were Hf complex of rac:meso=1:1. This crude product was collected and stored in the oil bath of 45° C., and 50 mL of dry toluene was added thereto with stirring for dissolving the crude product. The solution was stored in a freezer of −30° C. for 3 days for recrystallization. The obtained red solid was filtered with a glass frit (G4) and washed twice with 3 mL of dry n-hexane, and dried under vacuum to obtain 1.0 g (1.2 mmol, 23% yield) of the final product of racemic body.

(13) .sup.1H-NMR (Tol-d.sub.3): δ 7.23 (d, J=9.0 Hz, 2H, 7,7′-H in indenyl), 6.98 (d, J=7.5 Hz, 2H, 5,5′-H in quinolinyl), 6.90 (d, J=7.0 Hz, 2H, 5,5′-H in indenyl), 6.82-6.79 (m, 2H, 7,7′-H in quinolinyl), 6.72 (dd, J.sub.1=8.5 Hz, J.sub.2=7.5 Hz, 2H, 6,6′-H in indenyl), 6.68-6.65 (m, 2H, 6,6′-H in quinolinyl), 6.57 (s, 2H, 3,3′-H in indenyl), 6.51 (d, J=8.5 Hz, 2H, 8,8′-H in quinolinyl), 3.81-3.66 (m, 4H, 2,2′-H in quinolinyl), 2.63-2.53 (m, 4H, 4,4′-H in quinolinyl), 2.03 (s, 6H, 2,2′-Me), 1.87-1.67 (m, 4H, 3,3′-H in quinolinyl), 0.82 (s, 6H, SiMe.sub.2)

Example: Preparation of Propylene-Based Elastomer

Examples 1 to 7

(14) A hexane solvent (5 kg/h) and ethylene and propylene monomers were continuously fed at a high pressure of 90 to 100 bar to a 1.5 L continuous stirred reactor which was preheated at 80° C., and solution polymerization was carried out at a pressure of 89 bar. 0.025 mM triphenylcarbenium tetrakis(pentafluorophenyl) borate cocatalyst was put in the reactor by providing high pressure argon. The transition metal compound (0.25 mM) of Preparation Example 2 treated with a triisobutylaluminum compound was put in a catalyst storage tank and subsequently put in the reactor by providing high pressure argon. These two components were separately pumped, and the reactor temperature was controlled by controlling the temperature of oil passing through a reactor jacket. The polymer density was controlled by varying a weight ratio of propylene/ethylene.

(15) After polymerization, the polymers were separated from a discharge stream, and unreacted ethylene and propylene were separated from a dilute mixture stream. The polymers thus obtained were dried in a vacuum oven at 80° C. for 12 hrs or longer and then physical properties thereof were measured.

(16) Polymerization conditions for the propylene-based elastomers of Examples 1 to 7 are given in Table 1.

Comparative Examples 1 to 4

(17) Commercially available propylene-based elastomers, Vistamaxx™6120, Vistamaxx™6202, Vistamaxx™3020, and Vistamaxx™3980 of Exxon Corp. were used as Comparative Examples 1 to 4, respectively and physical properties thereof were measured by the following method.

(18) <Measurement Method of Physical Properties of Propylene Elastomer>

(19) Measurement of Triad Tacticity

(20) The copolymers of examples and comparative examples were analyzed by .sup.13C-NMR to calculate peak areas of PPP(mm), PPP(mr) and PPP(rr). Their triad tacticity was calculated, based on the following Mathematical Equation 1. In this regard, a 600 MHz Bruker Avance III HD NMR instrument was used for measurement, and each copolymer was dissolved in a 1,1,2,2,-tetrachloroethane solvent, and analyzed at 120° C.
triad tacticity (%)=PPP(mm)/{PPP(mm)+PPP(mr)+PPP(rr)}*100  [Mathematical Equation 1]

(21) Measurement of Density

(22) Density was measured at 23° C. using METTLER TOLEDO XS104 in accordance with the ASTM D1505 standard, and given in the following Tables 2 and 3.

(23) Measurement of MFR

(24) MFR was measured at 230° C. under a load of 2.16 kg using a Dynisco D4002HV instrument in accordance with the ASTM D1238 standard, and given in the following Tables 2 and 3.

(25) Measurement of Tensile Strength and Elongation

(26) Tensile strength and elongation were measured using an INSTRON 4465 instrument in accordance with the ASTM D638 standard, and given in the following Tables 4 and 5.

(27) Measurement of Hardness

(28) Hardness was measured using Mitutoyo CTS-103 and CTS-104 instruments in accordance with the ASTM D2240 standard, and given in the following Tables 4 and 5.

(29) Measurement of Flexural Strength

(30) Flexural strength was measured using an INSTRON 3365 instrument in accordance with the ASTM D790 standard, and given in the following Tables 4 and 5.

(31) Measurement of Tear Strength

(32) Tear strength was measured using an INSTRON 3365 instrument in accordance with the ASTM D624 standard, and given in the following Tables 4 and 5.

(33) TABLE-US-00001 TABLE 1 Polymerization conditions of examples Polymerization Ethylene/ Catalyst Cocatalyst AlR3 temperature Propylene Ethylene propylene Yield Activity Unit ml/min ml/min ml/mim ° C. kg/h kg/h mol ratio g/h kg/g (catalyst) Example 1 3.00 3.00 1.6 77.8 1.8 0.23 0.192 909 244.6 Example 2 3.25 3.25 5.0 78.8 1.8 0.22 0.183 1027 254.8 Example 3 3.00 3.00 1.6 77.5 1.8 0.18 0.167 865 232.5 Example 4 2.20 2.20 5.0 77.9 1.8 0.20 0.167 871 319.5 Example 5 1.00 1.00 5.0 80.0 1.8 0.18 0.150 1034 834.3 Example 6 1.60 0.80 2.6 75.6 1.8 0.15 0.125 770 388.2 Example 7 3.00 3.00 1.6 77.0 1.8 0.14 0.117 873 234.7

(34) TABLE-US-00002 TABLE 2 Evaluation of physical properties of examples Content of repeating unit Propylene Ethylene (% by (% by Triad tacticity Example weight) weight) Density MFR mm mr rr Example 1 84.0 16.0 0.861 31.0 61.5 32.8 5.7 Example 2 84.6 15.4 0.863 37.2 63.5 31.5 4.9 Example 3 84.9 15.1 0.867 36.8 64.2 30.6 5.1 Example 4 85.3 14.7 0.870 47.6 65.0 30.4 4.6 Example 5 86.4 13.6 0.874 37.8 67.2 28.8 4.0 Example 6 87.4 12.6 0.878 30.2 70.4 26.0 3.6 Example 7 87.9 12.1 0.879 52.7 71.3 24.9 3.8

(35) TABLE-US-00003 TABLE 3 Evaluation of physical properties of comparative examples Content of repeating unit Propylene Ethylene Comparative (% by (% by Den- Triad tacticity Example weight) weight) sity MFR mm mr rr Comparative 83.4 16.6 0.862 3.0 57.8 30.6 11.7 Example 1 Comparative 84.0 16.0 0.863 20 58.5 30.3 11.2 Example 2 Comparative 87.2 12.8 0.874 3.0 67.2 25.8 7.0 Example 3 Comparative 89.1 10.9 0.878 8.0 70.0 23.4 6.6 Example 4

(36) TABLE-US-00004 TABLE 4 Evaluation of physical properties of examples Physical properties ASTM Unit Example 1 Example 2 Example 5 Example 6 Elongation D638 % >1000 >1000 >1000 927.1 Tensile D638 Kgf/cm.sup.2 132.7 137.7 195.1 227.8 strength (at Break) Tensile D638 Kgf/cm.sup.2 16.7 25.0 51.8 63.0 strength (100% strain) Tensile D638 Kgf/cm.sup.2 19.5 29.4 54.9 61.9 strength (200% strain) Tensile D638 Kgf/cm.sup.2 22.7 34.3 59.1 66.3 strength (300% strain) Tensile D638 Kgf/cm.sup.2 37.3 50.2 79.5 106.7 strength (500% strain) Tear strength D624 N/cm 319.6 415.7 738.6 770.3 Flexural D790 Kgf/cm.sup.2 15.5 20.4 29.6 48.8 Strength Flexural D790 Kgf/cm.sup.2 178.1 232.0 440.7 781.9 modulus (1% secant) Hardness D2240 — 61.1 68.9 75.4 87.9 (Shore A) Hardness D2240 — 12.8 16.0 28.0 34.3 (Shore D)

(37) TABLE-US-00005 TABLE 5 Evaluation of physical properties of comparative examples Physical Comparative Comparative Comparative Comparative properties ASTM Unit Example 1 Example 2 Example 3 Example 4 elongation D638 % >1000 >1000 777.1 861.5 Tensile D638 Kgf/cm.sup.2 143.9 99.8 242.8 245.8 strength (at Break) Tensile D638 Kgf/cm.sup.2 17.1 16.2 46.0 61.2 strength (100% strain) Tensile D638 Kgf/cm.sup.2 19.8 18.7 47.5 60.0 strength (200% strain) Tensile D638 Kgf/cm.sup.2 23.2 21.4 52.3 63.9 strength (300% strain) Tensile D638 Kgf/cm.sup.2 35.1 29.5 90.6 100.5 strength (500% strain) Tear strength D624 N/cm 346.0 347.7 650.6 730.7 Flexural D790 Kgf/cm.sup.2 10.6 10.5 32.3 47.3 Strength Flexural D790 Kgf/cm.sup.2 109.2 111.2 372.3 737.2 modulus (1% secant) Hardness D2240 — 57.8 58.0 84.8 91.9 (Shore A) Hardness D2240 — 13.0 11.2 28.4 35.1 (Shore D)

(38) Referring to Tables 2 to 5 and FIG. 1, it was confirmed that ethylene content x and triad tacticity y in the propylene-based copolymers of Examples 1 to 7 satisfy a relationship of y≧−2.27x+97.0, and the copolymers exhibit excellent mechanical properties such as elongation, flexural modulus, tear strength, etc.

(39) In contrast, it was confirmed that ethylene content x and triad tacticity y of the propylene-based copolymers of Comparative Examples 1 to 4 do not satisfy the above relationship, and the copolymers exhibit low values in mechanical properties such as elongation, flexural modulus, tear strength, etc., compared to the propylene-based copolymers of Examples.

(40) Accordingly, it is suggested that the propylene-based copolymers of Examples have high tacticity, considering their ethylene content, and therefore, they are excellent in the mechanical properties such as elongation, flexural modulus, strength, etc., compared to conventional propylene-based copolymers.