Polyolefin
The present invention relates to polyolefin. More specifically, the present invention relate s to polyolefin having excellent dart drop impact strength, and exhibiting improved transparency and satisfying one of the following 1)˜4): 1) when density is 0.9165 g/cm 3 or more and less than 0.9175 g/cm 3 , the content of SCB (Short Chain Branch) is 9.5 to 10.5 wt %, 2) when density is 0.9175 g/cm 3 or more and less than 0.9185 g/cm 3 , the content of SCB (Short Chain Branch) is 9.0 to 10.0 wt %, 3) when density is 0.9185 g/cm 3 or more and less than 0.9195 g/cm 3 , the content of SCB (Short Chain Branch) is 8.5 to 9.5 wt %, 4) when density is 0.9195 g/cm 3 or more and less than 0.9205 g/cm 3 , the content of SCB (Short Chain Branch) is 7.5 to 8.5 wt %, wherein the density is measured according to ASTM D1505.
1. A polyolefin satisfying one of the following 1 to 4:
1) when a density is 0.9165 g/cm 3 or more and less than 0.9175 g/cm 3 , a content of SCB (Short Chain Branch) is 9.5 to 10.5 wt %,
2) when a density is 0.9175 g/cm 3 or more and less than 0.9185 g/cm 3 , a content of SCB (Short Chain Branch) is 9.0 to 10.0 wt %,
3) when a density is 0.9185 g/cm 3 or more and less than 0.9195 g/cm 3 , a content of SCB (Short Chain Branch) is 8.5 to 9.5 wt %,
4) when a density is 0.9195 g/cm 3 or more and less than 0.9205 g/cm 3 , a content of SCB (Short Chain Branch) is 7.5 to 8.5 wt %,
wherein the density is measured according to ASTM D1505,
wherein the content of SCB is measured using 1 H NMR spectroscopy, and
wherein the polyolefin has a melt index (MI 2.16 ) measured under a load of 2.16 kg and a temperature of 190° C. according to ASTM D1238 of 0.5 to 1.5 g/10 min.
2. The polyolefin according to claim 1 , wherein a polyolefin film (BUR 2.3, film thickness 55 to 65 μm), prepared from the polyolefin using a film applicator, has a haze 11% or less, measured according to ISO 13468.
3. The polyolefin according to claim 1 , wherein a polyolefin film (BUR 2.3, film thickness 55 to 65 μm), prepared from the polyolefin using a film applicator, has a dart drop impact strength of 850 g or more, measured according to ASTM D 1709 [Method A].
4. The polyolefin according to claim 1 , wherein the polyolefin is copolymer of ethylene and alpha olefin.
5. The polyolefin according to claim 4 , wherein the alpha olefin includes one or more of propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene, 1-undecene, 1-dodecene, 1-tetradecene, 1-hexadecene, or 1-eicosene.
6. The polyolefin according to claim 1 , wherein the polyolefin is prepared by polymerizing olefin monomers, in the presence of a hybrid supported metallocene catalyst comprising one or more first metallocene compounds selected from a compound represented by Chemical Formula 1; one or more second metallocene compounds selected from a compound represented by Chemical Formula 2; and a carrier supporting the first and second metallocene compounds,
in Chemical Formula 1,
Q 1 and Q 2 are identical to or different from each other, and each independently, halogen, a C1-C20 alkyl group, a C2-C20 alkenyl group, a C2-C20 alkoxyalkyl group, a C6-C20 aryl group, a C7-C20 alkylaryl group, or a C7-C20 arylalkyl group;
T 1 is carbon, silicon or germanium;
M 1 is a Group 4 transition metal;
X 1 and X 2 are identical to or different from each other, and each independently, halogen, a C1-C20 alkyl group, a C2-C20 alkenyl group, a C6-C20 aryl group, a nitro group, an amido group, a C1-C20 alkylsilyl group, a C1-C20 alkoxy group, or a C1-C20 sulfonate group; and
R 1 to R 14 are identical to or different from each other, and each independently, hydrogen, halogen, a C1-C20 alkyl group, a C1-C20 haloalkyl group, a C2-C20 alkenyl group, a C1-C20 alkylsilyl group, a C1-C20 silylalkyl group, a C1-C20 alkoxysilyl group, a C1-C20 alkoxy group, a C6-C20 aryl group, a C7-C20 alkylaryl group, or a C7-C20 arylalkyl group, or two or more neighboring groups of R 1 to R 14 are connected with each other and together with the carbon atoms to which they are attached to form a substituted or unsubstituted aliphatic or aromatic ring;
in Chemical Formula 2,
Q 3 and Q 4 are identical to or different from each other, and each independently, halogen, a C1-C20 alkyl group, a C2-C20 alkenyl group, a C2-C20 alkoxyalkyl group, a C6-C20 aryl group, a C7-C20 alkylaryl group, or a C7-C20 arylalkyl group;
T 2 is carbon, silicon or germanium;
M 2 is a Group 4 transition metal;
X 3 and X 4 are identical to or different from each other, and each independently, halogen, a C1-C20 alkyl group, a C2-C20 alkenyl group, a C6-C20 aryl group, a nitro group, an amido group, a C1-C20 alkylsilyl group, a C1-C20 alkoxy group, or a C1-C20 sulfonate group; and
R 15 to R 28 are identical to or different from each other, and each independently, hydrogen, halogen, a C1-C20 alkyl group, a C1-C20 haloalkyl group, a C2-C20 alkenyl group, a C2-C20 alkoxyalkyl group, a C1-C20 alkylsilyl group, a C1-C20 silylalkyl group, a C1-C20 alkoxysilyl group, a C1-C20 alkoxy group, a C6-C20 aryl group, a C7-C20 alkylaryl group, or a C7-C20 arylalkyl group, provided that R 20 and R 24 are identical to or different from each other, and each independently, a C1 to C20 alkyl group, or two or more neighboring groups of R15 to R 28 are connected with each other and along with the carbon atoms to which they are attached to form a substituted or unsubstituted aliphatic or aromatic ring.
7. The polyolefin according to claim 6 , wherein the compound represented by Chemical Formula 1 is any one of compounds represented by the following structural formulas:
8. The polyolefin according to claim 6 , wherein the compound represented by Chemical Formula 2 is any one of compounds represented by the following structural formulas:
9. The polyolefin according to claim 6 , wherein a mole ratio of the first and second metallocene compounds is 1:1 to 10:1.
10. The polyolefin according to claim 6 , which has an ethylene sequence inhomogeneity(I) calculated by Equation 1 of 1.25 to 1.40, when analyzed by SSA(Successive Self-nucleation and Annealing):
Inhomogeneity (I)= L w /L n [Equation 1]
in the Equation 1,
L w is weighted average (unit:nm) of ESL (Ethylene Sequence Length), and L n is arithmetic mean (unit:nm) of ESL (Ethylene Sequence Length).
11. The polyolefin according to claim 10 , wherein the L n is calculated by Equation 2, and the L w is calculated by Equation 3:
L
n
=
S
1
L
1
+
S
2
L
2
+
S
3
L
3
+
⋯
+
S
i
L
i
S
1
+
S
2
+
S
3
+
⋯
+
S
i
=
∑
f
i
L
i
[
Equation
2
]
L
w
=
S
1
L
1
2
+
S
2
L
2
2
+
S
3
L
3
2
+
⋯
+
S
i
L
i
2
S
1
L
1
+
S
2
L
2
+
S
3
L
3
+
⋯
+
S
i
L
i
=
∑
f
i
L
i
2
∑
f
i
L
i
[
Equation
3
]
in Equations 2 and 3,
S i is an area of each melting peak measured in a SSA thermogram, and
L i is ASL (Average Ethylene Sequence Length) corresponding to each melting peak in the SSA thermogram.
12. The polyolefin according to claim 10 , wherein the SSA thermogram is conducted by heating the polyolefin to a first heating temperature of 120 to 124° C. using differential scanning calorimetry, maintaining for 15 to 30 minutes, and then, cooling to 28 to 32° C., and while decreasing heating temperature by stages with (n+1)th heating temperature being 3 to 7° C. lower than nth heating temperature, repeating heating-annealing-quenching until a final heating temperature becomes 50 to 54° C., and finally, increasing the temperature from 30° C. to 160° C.
13. The polyolefin according to claim 6 , wherein in Chemical Formula 1, R 11 to R 14 are each independently a C1 to C20 alkyl group, R 1 is hydrogen or a C1 to C20 alkyl group, R 2 to R 10 are each hydrogen, Q 1 and Q 2 are each independently a C1 to C20 alkyl group or a C6 to C20 aryl group, X 1 and X 2 are each independently halogen, and M 1 is Ti, Zr or Hf.
14. The polyolefin according to claim 6 , wherein in Chemical Formula 2, R 25 and R 28 are each independently hydrogen, a C1 to C20 alkyl group, or a C2 to C20 alkoxyalkyl group, Q 3 and Q 4 are independently a C1 to C20 alkyl group or a C2 to C20 alkoxyalkyl group, X 3 and X 4 are each independently halogen, and M 2 is Ti, Zr or Hf.