Multilayer film
Multilayer film of at least three layers, one core layer and at least one sealing layer wherein 5 the sealing layer comprises a linear low density polyethylene having a density in the range of 0.915 to 0.925 g/cm3, and the core layer comprises a propylene 1-hexene copolymer, said copolymer has an 1-hexene content in the range of 4.5 to 8.0 wt.-% and a xylene soluble fraction of more than 10.0 wt.-%.
1. A multilayer film comprising at least three layers, one 1 st sealing layer (SL1), one core layer (CL) and one outer layer (OL), the stacking order of the at least three layers is (SL1)/(CL)/(OL),
wherein;
(a) the 1 st sealing layer (SL1) comprises at least 90 wt. %, based on the total weight of the 1 st sealing layer (SL1), of a 1 st base polymer composition (BC1), said 1 st base polymer composition (BC1) comprises at least 70 wt. %, based on the total weight of the 1 st base polymer composition (BC1), of a 1 st linear low density polyethylene (LLDPE1), said 1 st linear low density polyethylene (LLDPE1) has a density measured according to ISO 1183-187 in the range of 0.890 to 0.925 g/cm 3 ;
(b) the core layer (CL) comprises at least 90 wt. %, based on the total weight of the core layer (CL), of a 2 nd base polymer composition (BC2), said 2 nd base polymer composition (BC2) comprises at least 90 wt. %, based on the total weight of the 2 nd base polymer composition (BC2), of a propylene 1-hexene copolymer (PHC); and
(c) the outer layer (OL) comprises at least 90 wt. %, based on the total weight of the outer layer (OL), of a 3 rd base polymer composition (BC3), said 3 rd base polymer composition (BC3) comprises at least 90 wt. %, based on the total weight of the 3 rd base polymer composition (BC3), of a polyolefin;
wherein said propylene 1-hexene copolymer (PHC) of the 2 nd base polymer composition (BC2) has:
(i) a 1-hexene content in the range of 4.5 to 8.0 wt. % based on the total weight of the propylene 1-hexene copolymer (PHC); and
(ii) a xylene soluble fraction (XCS) determined at 25° C. according to ISO 16152 of 18.0 to 35.0 wt. % based on the total weight of the propylene 1-hexene copolymer (PHC), wherein the xylene soluble fraction (XCS) of the propylene 1-hexene copolymer (PHC) has a 1-hexene content in the range of 5.0 to 12.0 wt. %, based on the total weight of the propylene 1-hexene copolymer (PHC), and
wherein the propylene 1-hexene copolymer (PHC) comprises a 1 st propylene 1-hexene copolymer (PHC-1) and a second propylene 1-hexene copolymer (PHC-2), wherein
(a′) said 1 st propylene 1-hexene copolymer (PHC-1) has a 1-hexene content in the range of 0.5 to 3.9 wt. % based on the total weight of the 1 st propylene 1-hexene copolymer (PHC-1), and
(b′) said 2 nd propylene 1-hexene copolymer (PHC-2) has a 1-hexene content in the range of 6.0 to 20.0 wt. % based on the total weight of the 2 nd propylene 1-hexene copolymer (PHC-2).
2. The multilayer film according to claim 1 , wherein the propylene 1-hexene copolymer (PHC) has:
(a) a molecular weight distribution (Mw/Mn) in the range of 3.0 to 4.3; and/or
(b) 2,1 erythro regio defects in the range of 0.40 to 0.55 mol. % determined by 13 C NMR spectroscopy and optionally an isotactic triad concentration of higher than 98% determined by 13 C NMR spectroscopy.
3. The multilayer film according to claim 1 , wherein the propylene 1-hexene copolymer (PHC) has:
(a) a melting temperature in the range of 133 to 140° C.; and/or
(b) a melt flow rate MFR 2 (230° C./2.16 kg) measured according to ISO 1133 in the range of 0.5 to 8.0 g/10 min.
4. The multilayer film according to claim 1 , wherein:
(a) the xylene soluble fraction (XCS) of the propylene 1-hexene copolymer (PHC) has a 1-hexene content in the range of 6.0 to 10.0 wt. %, based on the total weight of the xylene soluble fraction (XCS) of the propylene 1-hexene copolymer (PHC); and/or
(b) the propylene 1-hexene copolymer (PHC) has a xylene soluble fraction (XCS) determined at 25° C. according to ISO 16152 in the range of 21.0 to 30.0 wt. % based on the total weight of the 1-hexene copolymer (PHC).
5. The multilayer film according to claim 1 , wherein the
1 st propylene 1-hexene copolymer (PHC-1) has a 1-hexene content in the range of 0.8 to 3.0 wt. % based on the total weight of the 1 st propylene 1-hexene copolymer (PHC-1).
6. The multilayer film according to claim 1 , wherein the propylene 1-hexene copolymer (PHC):
(a) fulfills the inequation (I):
6.00
≤
C
6
(
P
H
C
)
C
6
(
P
H
C
-
1
)
*
[
P
H
C
-
1
]
[
P
H
C
]
≤
8.50
wherein:
C6 (PHC-1) is the 1-hexene content of the 1 st propylene 1-hexene copolymer (PHC-1) based on the total weight of the 1 st propylene 1-hexene copolymer (PHC-1) [in wt.];
C6 (PHC) is the 1-hexene content of the propylene 1-hexene copolymer (PHC) based on the total weight of the propylene 1-hexene copolymer (PHC) [in wt. %];
[PHC-1]/[PHC] is the weight ratio between the 1 st propylene 1-hexene copolymer (PHC-1) and the propylene 1-hexene copolymer (PHC) [in g/g]; and
(b) the propylene 1-hexene copolymer (PHC) optionally further fulfills the inequation (II):
0.70
≤
C
6
(
P
H
C
-
2
)
*
[
P
H
C
-
2
]
[
P
H
C
]
C
6
(
P
H
C
)
≤
0.95
wherein:
C6 (PHC-2) is the 1-hexene content of the 2 nd propylene 1-hexene copolymer (PHC-2) based on the total weight of the 2 nd propylene 1-hexene copolymer (PHC-2) [in wt. %];
C6 (PHC) is the 1-hexene content of the propylene 1-hexene copolymer (PHC) based on the total weight of the propylene 1-hexene copolymer (PHC) [in wt. %];
[PHC-2]/[PHC] is the weight ratio between the 2 nd propylene 1-hexene copolymer (PHC-2) and the propylene 1-hexene copolymer (PHC) [in g/g].
7. The multilayer film according to claim 1 , wherein:
the total amount of the 1 st propylene 1-hexene copolymer (PHC-1) and the 2 nd propylene 1-hexene copolymer (PHC-2) together is at least 95 wt. % based on the total weight of the propylene 1-hexene copolymer (PHC); or
(b) the propylene 1-hexene copolymer (PHC) consists of the propylene 1-hexene copolymers (PHC-1) and (PHC-2).
8. The multilayer film according to claim 1 , wherein the weight ratio [(PHC-1)/(PHC-2)] between the 1 st propylene 1-hexene copolymer (PHC-1) and the 2 nd propylene 1-hexene copolymer (PHC-2) is in the range of 30/70 to 50/50.
9. The multilayer film according to claim 1 , wherein:
(a) the core layer (CL) comprises at least 90 wt. %, based on the total weight of the core layer (CL), of the 2nd base polymer composition (BC2) and the remaining part up to 100 wt. %, based on the total weight of the core layer (CL), are additives (AD); and
(b) optionally the 1 st sealing layer (SL1) comprises at least 90 wt. %, based on the total weight of the 1 st sealing layer (SL1), of the 1 st base polymer composition (BC1) and the remaining part up to 100 wt. %, based on the total weight of the 1 st sealing layer (SL1), are additives (AD); and
(c) optionally the outer layer (OL) comprises at least 90 wt. %, based on the total weight of the outer layer (OL), of the 3 rd base polymer composition (BC3) and the remaining part up to 100 wt. %, based on the total weight of the outer layer (OL), are additives (AD).
10. The multilayer film according to claim 1 , wherein the 2 nd base polymer composition (BC2) consists of the propylene 1-hexene copolymer (PHC).
11. The multilayer film according to claim 1 , wherein the outer layer (OL) is:
(a) a heat shield layer (HSL), wherein the 3 rd base polymer composition (BC3) is a 3 rd base polymer composition (BC3B), wherein the polyolefin is a polypropylene having a melting temperature of at least 150° C.; or
(b) a 2 nd sealing layer (SL2), wherein the 3 rd base polymer composition (BC3) is a 3 rd base polymer composition (BC3A);
said 3 rd base polymer composition (BC3A) comprises at least 70 wt. %, based on the total weight of the 3 rd base polymer composition (BC3A), of a 2 nd linear low density polyethylene (LLDPE2), said 2 nd linear low density polyethylene (LLDPE2) has a density in the range of 0.890 to 0.925 g/cm 3 .
12. The multilayer film according to claim 11 , wherein the 1 st linear low density polyethylene (LLDPE1) and the 2 nd linear low density polyethylene (LLDPE2) have:
(a) a melt flow rate MFR 2 (190° C./2.16 kg) measured according to ISO 1133 in the range of 0.5 to 8.0 g/10 min; and/or
(b) a comonomer content in the range of 1.5 to 5.0 mol. %, the comonomers are selected from the group consisting of 1-butene, 1-hexene, 1-octene and mixtures thereof.
13. The multilayer film according to claim 1 , wherein:
(a) the 1 st base polymer composition (BC1)
(a1) consists of the 1 st linear low density polyethylene (LLDPE1), or
(a2) comprises 75 to 95 wt. %, based on the total weight of the 1 st base polymer composition (BC1), of the 1 st linear low density polyethylene (LLDPE1); and
5 to 25 wt. %, based on the total weight of the 1 st base polymer composition (BC1), of a 1 st low density polyethylene (LDPE1) having a density measured according to ISO 1183-187 in the range of 0.915 to 0.935 g/cm 3 .
14. The multilayer film according to claim 11 , wherein:
(a) the 1 st linear low density polyethylene (LLDPE1) and the 2 nd linear low density polyethylene (LLDPE2) are identical, or
(b) the 1 st base polymer composition (BC1) and the 3 rd base polymer composition (BC3A) are identical.
15. The multilayer film according to claim 11 , wherein the film is a multilayer blown film, wherein said multilayer blown film consists of:
(a) the 1 st sealing layer (SL1), the core layer (CL) and the 2 nd sealing layer (SL2), the stacking order of the three layers is (SL1)/(CL)/(SL2); or
(b) the 1 st sealing layer (SL1), the core layer (CL) and the heat shield layer (HSL), the stacking order of the three layers is (SL1)/(CL)/(HSL).
16. The multilayer film according to claim 1 , wherein the 2 nd propylene 1-hexene copolymer (PHC-2) has a 1-hexene content in the range of 6.9 to 11.0 wt. % based on the total weight of the 2 nd propylene 1-hexene copolymer (PHC-2).
17. The multilayer film according to claim 9 , wherein the additives (AD) are selected from the group consisting of antioxidants, light stabilizers, acid scavengers, processing aids, anti-blocking aids, nucleating agents, slip agents and mixtures thereof.
18. The multilayer film according to claim 11 , wherein:
(b) the outer layer (OL) is the 2 nd sealing layer (SL2), wherein further the 3 rd base polymer composition (BC3A):
(b1) consists of the 2 nd linear low density polyethylene (LLDPE2), or
(b2) comprises 75 to 85 wt. %, based on the total weight of the 3 rd base polymer composition (B3CA), of the 2 nd linear low density polyethylene (LLDPE2); and
5 to 25 wt. %, based on the weight of the total weight of the 3 rd base polymer composition (BC3A) of a 1 st low density polyethylene (LDPE1) having a density measured according to ISO 1183-187 in the range of 0.915 to 0.935 g/cm 3 .