Film layer

Patent metadata

Field	Value
Publication number	US-10494465-B2
Application number	US-201515528020-A
Country	US
Kind code	B2
Filing date	Nov 18, 2015
Priority date	Nov 26, 2014
Publication date	Dec 3, 2019
Grant date	Dec 3, 2019

Abstract

The present invention relates to a film comprising at least one layer which comprises a polymer composition comprising (a) a multimodal polymer of ethylene.

First claim

The invention claimed is:

1. A film comprising at least one layer which comprises a polymer composition comprising a multimodal polymer of ethylene with at least two different comonomers selected from alpha-olefins having from 4 to 10 carbon atoms, which multimodal polymer of ethylene has a density of 910 to 935 kg/m 3 ,
wherein the polymer composition has:
hot tack temperature, i.e. lowest temperature to get maximum hot tack force, of less than 112° C., when determined according to ASTM F 1921-98 (2004), method B, and measured from a film sample (40 μm thickness) consisting of the polymer composition, and
maximum hot tack force, of 1.95 N or more, when determined according to ASTM F 1921-98 (2004), method B, and measured from a film sample (40 μm thickness) consisting of the polymer composition;
wherein the multimodal polymer of ethylene has a MFR 21 /MFR 2 of 13 to 35 (MFR 21 at 190° C. under 21.6 kg load).

2. The film according to claim 1 , wherein the polymer composition has one or two of the following features:
the hot tack temperature is 80° C. or more to less than 112° C., and/or
the hot tack is up to 5.0 N.

3. The film according to claim 1 , wherein the multimodal polymer of ethylene has one or more, in any order:
a) MFR 2 of 0.5 to 10 g/10 min (according to ISO 1133 at 190° C. under 2.16 kg load), and/or
b) MWD of 5 or less.

4. The film according to claim 1 , wherein the multimodal polymer of ethylene comprises at least:
an ethylene polymer component (A) and
an ethylene polymer component (B),
wherein the MFR 2 of the ethylene polymer component (A) is different from the MFR 2 of the ethylene polymer component (B).

5. The film according to claim 4 , wherein a MFR 2 of ethylene polymer component (A) is higher than a MFR 2 of ethylene polymer component (B).

6. The film according to claim 4 , wherein a ratio of [an amount (mol %) of comonomers selected from alpha-olefins having from 4 to 10 carbon atoms present in ethylene polymer component (A)] to [an amount (mol %) of at least two comonomers selected from alpha-olefins having from 4 to 10 carbon atoms of the multimodal polymer of ethylene] is 0.2 to 0.6.

7. The film according to claim 4 , wherein an amount (mol %) of comonomers selected from alpha-olefins having from 4 to 10 carbon atoms present in the ethylene polymer component (A) is 0.03 to 5.0 mol %.

8. The film according to claim 4 , wherein a density of the ethylene polymer component (A) is 925 to 950 kg/m 3 .

9. The film according claim 1 , wherein the at least two comonomers selected from alpha-olefins having from 4 to 10 carbon atoms are 1-butene and 1-hexene.

10. The film according to claim 1 , wherein the multimodal polymer of ethylene is further multimodal with respect to comonomer type and/or comonomer content.

11. The film according to claim 1 , wherein the multimodal polymer of ethylene is further multimodal with respect to density.

12. The film according to claim 1 , wherein density of the multimodal polymer of ethylene is 915 to 930, kg/m 3 .

13. The film according to claim 1 , wherein the multimodal polymer of ethylene has MFR 21 /MFR 2 of 13 to 30.

14. The film according to claim 1 , wherein the multimodal polymer of ethylene is multimodal with respect to MFR, type of the comonomer, comonomer content and density.

15. The film according to claim 1 , wherein the polymer composition has a tensile modulus in machine direction (MD) of 200 to 350 MPa, when determined according to ISO 527-1 and ISO 527-3 and measured from a film sample (40 μm thickness) consisting of the polymer composition.

16. The film according to claim 1 , wherein polymer composition has a shear thinning value SHI 2.7/210 of 1.5 to 7.

17. The film according to claim 1 , wherein the multimodal polymer of ethylene is produced using a single site catalyst.

Assignees

• Borealis Ag

Inventors

• Kela Jarmo
• Niedersuss Peter
• Aarila Jari
• Vahteri Markku
• Prades Floran
• Jamieson John
• Wever Willem

Classifications

• B32B2250/05

  5 or more layers · CPC title

• C08J5/18 Primary

  Manufacture of films or sheets · CPC title

• B32B2307/54

  Yield strength; Tensile strength · CPC title

• C08F10/02

  Ethene · CPC title

• C08F2500/18

  Bulk density · CPC title