Title of Invention

“POLYETHYLENE BLEND COMPONENT AND BLENDS CONTAINING THE SAME”

Abstract

According to one aspect, the present invention relates to a low-density polyethylene having a melt index MFR2 of 2.5 to 10.0 g/10 min, a density of 910 to 935 kg/m3, and a dynamic viscosity ?o.o5 at a shear rate of 0.05 rad/s and a dynamic viscosity ?300 at a shear rate of 300 rad/s which satisfy the following relationship: ?300 = 108*Pas + 0.0253*?o.o5. According to a second aspect, the present invention relates to a low-density polyethylene having a melt index MFR2 of 2.5 to 10.0 g/10 min, a density of 910 to 935 kg/m3, and a phase shift d0.5 at a frequency of 0.5 rad/s and a phase shift d300 at a frequency of 300 rad/s, which satisfy the following relationship:tan d300 = 0.45 + 0.164*tan d0.5.

Full Text

The present invention deals with polyethylene blends to be used in extrusion coating. In extrusion coating a thin film of polymer melt is extruded through a falt die and pressed onto a moving substrate. Extrusion coating is discussed, ............ We Claim: 1. A low-density polyethylene, having - a melt index MFR2 of 2.5 to 10.0 g/10 min, - a density of 910 to 935 kg/m3, - a dynamic viscosity  at a shear rate of 0.05 rad/s and a dynamic viscosity 300 at a shear rate of 300 rad/s which satisfy the following relationship: (Formula Removed) wherein the dynamic viscosity 0.05 at a shear rate of 0.05 rad/s is within the range of 1000 to 10000 Pa*s, and - a phase shift δ0.5 at a frequency of 0.5 rad/s and a phase shift δ300 at a frequency of 300 rad/s, which satisfy the following relationship (Formula Removed) 2. The low-density polyethylene as claimed in claim 1, wherein the melt index MFR2 is within the range of 2.5 to 6.5 g/10 min. 3. The low-density polyethylene as claimed in one of the preceding claims, wherein tan δ0.5 at a frequency of 0.5 rad/s is within the range of 1.5 to 3.0. 4. The low-density polyethylene as claimed in one of the preceding claims, wherein tan δ300 at a frequency of 300 rad/s is within the range of 0.8 to 1.0. 5. The low-density polyethylene as claimed in one of the preceding claims, having a shear thinning index SHI1/100 of 20 to 60. 6. The low-density polyethylene as claimed in one of the preceding claims, having a number average molecular weight Mn of 8000 to 30000 g/mol. 7. The low-density polyethylene as claimed in one of the preceding claims, having a weight average molecular weight Mw of 400000 to 600000 g/mol. 8. The low-density polyethylene as claimed in one of the preceding claims, having a z-average molecular weight Mz of 2000000 to 4000000 g/mol. 9. The low-density polyethylene as claimed in one of the preceding claims, having a molecular weight distribution Mw/Mn of 20 to 50. 10. The low-density polyethylene as claimed in one of the preceding claims, having a storage modulus G'(5 kPa), measured at a loss modulus G" of 5 kPa, within the range of 3000 to 3600 Pa. 11. A polymer blend, comprising - 5 to 60 wt% of a low-density polyethylene as claimed in claims 1 to 10, and - 40 to 95 wt% of a multimodal linear low density polyethylene prepared in the presence of a single-site catalyst and which comprises a) 30 to 70 wt%, based on the total multimodal linear low density ethylene polymer, of a low molecular component having a density of from 930 to 950 kg/m3, and b) 70 to 30 wt%, based on the multimodal linear low density ethylene polymer, of a high molecular weight component having a density of from 880 to 915 kg/m3. 12. The polymer blend as claimed in claim 11, wherein the multimodal linear low density polyethylene has a melt index MFR2 of from 3 to 40 g/10 min. 13. The polymer blend as claimed in claim 11 or 12, wherein the multimodal linear low density polyethylene has a density from 900 to 935 kg/m3. 14. The polymer blend as claimed in claims 11 to 13, wherein the multimodal linear low density ethylene polymer has been produced by polymerising ethylene and at least one alpha-olefin comonomer having from 4 to 10 carbon atoms. 15. The polymer blend as claimed in claims 11 to 14, wherein the blend has a value of the dynamic viscosities 300 and 5 meeting the following condition: 300 ≤ 0.233 • .5 + 50. 16. The polymer blend as claimed in claims 11 to 15, wherein the blend has a value of tan δ 0.5 of about 10 or less. 17. The polymer blend as claimed in claims 11 to 16, wherein the blend has a value of tan 8300 of about 2.0 or less. 18. The polymer blend as claimed in claims 11 to 17, wherein the blend has a density within the range from 900 kg/m3 to 965 kg/m3. 19. The polymer blend as claimed in claims 11 to 18, wherein the density, p, and the melting temperature, Tm, of the blend satisfy the following relationship: Tm ≥ 1.6  - 1360 20. The polymer blend, as claimed in claim 11, wherein the blend has a density within the range from 900 kg/m3 to 965 kg/m3, an MFR2 of from 2 to 50 g/10min, and a value of the dynamic viscosities 300 and 0.5 meeting the following condition: 300 ≤ 0.233 • 0.5 + 50. 21. A process for the preparation of the low-density polyethylene as claimed in claims 1 to 10, wherein polymerization is carried out in a high pressure process, wherein the polymerization reactor comprises at least two reaction zones and one or more initiators selected from peroxides are separately fed to at least two of these reaction zones, wherein 50 to 80 wt% of the initiator(s) are fed into a first reaction zone and 50 to 20 wt% of the initiator(s) are fed into a second reaction zone which is located downstream the first reaction zone. 22. A polymer blend as claimed in claims 11 to 20 for using in extrusion coating.

Documents:

2432-DELNP-2008-Claims-(22-11-2011).pdf

2432-DELNP-2008-Correspondence Others-(22-11-2011).pdf

2432-DELNP-2008-Drawings-(22-11-2011).pdf

2432-DELNP-2008-Form-3-(22-11-2011).pdf

2432-DELNP-2008-GPA-(24-09-2008).pdf

Drawings.pdf

Form-1.pdf

Form-3.pdf

Form-5.pdf