Multimodal polyolefin resin, and molded body manufactured therefrom
Multimodal polyolefin resins for manufacturing films, pipes, hollow molded articles having high melt strength and excellent formability, mechanical strength, processability and appearance are described. The resins have: density is 0.930-0.960 g/cm 3 ; melt flow index is 0.01-10.0 g/10 minutes; ratio Mw/Mn is 10-60; and two or more peaks appear when molecular weight is measured by GPC. In molded pipe, the Mw of polymer collected at position B is 0.1% greater than Mw of polymer collected at position A; polymer having Mw of 10,000 or less among polymers collected at position A is 0.1% greater than the amount of polymer having Mw of 10,000 or less among polymers collected at position B; and the amount of polymer having Mw of 1,000,000 or more among polymers collected at position B is 0.1% greater than the amount of polymer having Mw of 1,000,000 or more among polymers collected at position A.
1. A polyolefin resin satisfying the following requirements (1) to (7):
(1) a density (d) is 0.930 to 0.960 g/cm 2 ;
(2) a melt flow index (MIP, 190° C., 5.0 kg load condition) is 0.01 to 10.0 g/10 minutes;
(3) a ratio (Mw/Mn, molecular weight distribution (MWD)) of weight average molecular weight (Mw) to number average molecular weight (Mn) which is measured by gel permeation chromatography (GPC) is in the range from 10 to 60;
(4) two or more peaks of molecular weight appear when measured by gel permeation chromatography (GPC);
(5) in a molded pipe, a weight average molecular weight (Mw) of the polymer taken at position B of Definition 1 below is 0.1% greater than a weight average molecular weight (Mw) of the polymer taken at position A;
(6) in a molded pipe, content of the polymer having a weight average molecular weight (Mw) of 10,000 or less in polymer taken at position A of Definition 1 below is 0.1% greater than the content of the polymer having a weight average molecular weight (Mw) of 10,000 or less in the polymer taken at position B;
(7) in a molded pipe, content of the polymer having a weight average molecular weight (Mw) of 1,000,000 or greater in the polymer taken at position B of Definition 1 below is 0.1% greater than a content of the polymer having a weight average molecular weight (Mw) of 1,000,000 or greater in the polymer taken at position A;
[Definition 1]
in a molded pipe having an SDR (SDR (Standard Dimension Ratio)=od/en) of 2 to 20,
position
A
=
id
2
+
(
en
×
0.4
)
-
id
2
+
(
en
×
0.6
)
From
pipe
center
position
B
=
id
2
+
(
en
×
0.8
)
-
id
2
+
(
en
×
1.0
)
From
pipe
center
where id is an inner diameter, od is an outside diameter, and en is a wall thickness.
2. The polyolefin resin as claimed in claim 1 , wherein the density (d) is 0.934 to 0.954 g/cm 2 ; the melt flow index (MIP, 190° C., 5.0 kg load condition) is 0.1 to 1 g/10 minutes; the ratio (Mw/Mn, MWD) of weight average molecular weight (Mw) to number average molecular weight (Mn) is 12 to 50 measured by gel permeation chromatography; a weight average molecular weight (Mw) of the polymer taken at position B of Definition 1 is 1% greater than a weight average molecular weight (Mw) of the polymer taken at position A; content of the polymer having a weight average molecular weight (Mw) of 10,000 or less in polymer taken at position A of Definition 1 is 1% greater than the content of the polymer having a weight average molecular weight (Mw) of 10,000 or less in the polymer taken at position B; and the content of the polymer having a weight average molecular weight (Mw) of 1,000,000 or greater in the polymer taken at position B of Definition 1 below is 1% greater than a content of the polymer having a weight average molecular weight (Mw) of 1,000,000 or greater in the polymer taken at position A.
3. The polyolefin resin as claimed in claim 1 , wherein the polyolefin resin has a weight average molecular weight (Mw, measured by gel permeation chromatography) of 100,000 to 400,000.
4. The polyolefin resin as claimed in claim 1 , wherein the olefin resin has a melt flow index ratio (SR) of 10 to 300.
5. The polyolefin resin as claimed in claim 1 , wherein the olefin resin has a relaxation time of 400 seconds or less.
6. The polyolefin resin as claimed in claim 1 , wherein the olefin resin has a Shear Thining Index (STI) of 20 to 100.
7. The polyolefin resin as claimed in claim 1 , wherein the olefin resin has a modulus ratio index (MRI) of 20 to 200.
8. The polyolefin resin as claimed in claim 1 , wherein the olefin resin has a Long Chain Branch Index (LCBI) of 1/1,000 C or less.
9. The polyolefin resin as claimed in claim 1 , further satisfying the following requirements (10) and (11):
(10) in a pipe water pressure test, which measures the time at which a pipe is broken by applying a stress corresponding to a pressure of 5.4 MPa with water at 80° C. in accordance with KS M 3408, the pipe breaking time exceeds 165; and
(11) in a pipe water pressure test, which measures the time at which a pipe is broken by applying a stress corresponding to a pressure of 12.4 Mpa is applied with water at 20° C. in accordance with KS M 3408, the pipe breaking time exceeds 100 hours.
10. The polyolefin resin as claimed in claim 1 , wherein the polyolefin resin is a homopolymer or a copolymer of an olefin monomer selected from the group consisting of ethylene, 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, 1-itocene, norbornene, norbornadiene, ethylidene norbornene, phenyl norbornene, vinyl norbornene, dicyclopentadiene, 1,4-butadiene, 1,5-butadiene, 1,5-pentadiene, 1,6-hexadiene, styrene, α-methylstyrene, divinylbenzene, 3-chloromethylstyrene and mixture thereof.
11. The polyolefin resin as claimed in claim 1 , wherein the polyolefin resin comprises 97 to 99.99% by weight of a main resin selected from ethylene, propylene, and mixtures thereof; and 0.01 to 3% by weight of a constituent unit derived from α-olefin having 4 to 10 carbon atoms.
12. A polyolefin resin satisfying the following requirements (1), (2), (8) and (9):
(1) a density (d) is 0.930 to 0.960 g/cm 2 ;
(2) a melt flow index (MIP, 190° C., 5.0 kg load condition) is 0.01 to 10.0 g/10 minutes;
(8) in a molded pipe, Z average molecular weight (Mz), measured by gel permeation chromatography (GPC), of the polymer taken at position B of Definition 1 below is 0.1% greater than the Z average molecular weight (Mz) of the polymer taken at position A; and
(9) in a molded pipe, Z+1 average molecular weight (Mz+1), measured by gel permeation chromatography (GPC), of the polymer taken at position B of Definition 1 below is 1% greater than the Z+1 average molecular weight (Mz+1) of the polymer taken at position A;
[Definition 1]
in a molded pipe having an SDR (SDR (Standard Dimension Ratio)=od/en) of 2 to 20,
position
A
=
id
2
+
(
en
×
0.4
)
-
id
2
+
(
en
×
0.6
)
From
pipe
center
position
B
=
id
2
+
(
en
×
0.8
)
-
id
2
+
(
en
×
1.0
)
From
pipe
center
where id is an inner diameter, od is an outside diameter, and en is a wall thickness.
13. The polyolefin resin as claimed in claim 12 , wherein the density (d) is 0.934 to 0.954 g/cm 3 ; a melt flow index (MIP, 190° C., 5.0 kg load condition) is 0.1 to 1 g/10 minutes; in a molded pipe, Z average molecular weight (Mz), measured by gel permeation chromatography (GPC), of the polymer taken at position B of Definition 1 below is 1% greater than the Z average molecular weight (Mz) of the polymer taken at position A; and in a molded pipe, Z+1 average molecular weight (Mz+1), measured by gel permeation chromatography (GPC), of the polymer taken at position B of Definition 1 below is 5% greater than the Z+1 average molecular weight (Mz+1) of the polymer taken at position A.
14. The polyolefin resin as claimed in claim 12 , wherein the Z average molecular weight (Mz, measured by gel permeation chromatography (GPC)) is 100,000 to 10,000,000, and the Z+1 average molecular weight (Mz+1, measured by gel permeation chromatography (GPC)) is 1,000,000 to 10,000,000.
15. The polyolefin resin as claimed in claim 12 , wherein the olefin resin has a melt flow index ratio (SR) of 10 to 300.
16. The polyolefin resin as claimed in claim 12 , wherein the olefin resin has a relaxation time of 400 seconds or less.
17. The polyolefin resin as claimed in claim 12 , wherein the olefin resin has a Shear Thining Index (STI) of 20 to 100.
18. The polyolefin resin as claimed in claim 12 , wherein the olefin resin has a modulus ratio index (MRI) of 20 to 200.
19. The polyolefin resin as claimed in claim 12 , wherein the olefin resin has a Long Chain Branch Index (LCBI) of 1/1,000 C or less.
20. The polyolefin resin as claimed in claim 12 , wherein the melt strength measured by a capillary rheological equipment is 1 cN or greater.
21. The polyolefin resin as claimed in claim 12 , wherein the polyolefin resin is a homopolymer or a copolymer of an olefin monomer selected from the group consisting of ethylene, 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, 1-itocene, norbornene, norbornadiene, ethylidene norbornene, phenyl norbornene, vinyl norbornene, dicyclopentadiene, 1,4-butadiene, 1,5-butadiene, 1,5-pentadiene, 1,6-hexadiene, styrene, α-methylstyrene, divinylbenzene, 3-chloromethylstyrene and mixture thereof.
22. The polyolefin resin as claimed in claim 12 , wherein the polyolefin resin comprises 97 to 99.99% by weight of a main resin selected from ethylene, propylene, and mixtures thereof; and 0.01 to 3% by weight of a constituent unit derived from α-olefin having 4 to 10 carbon atoms.