Low haze polyethylene polymer compositions

Patent metadata

Field	Value
Publication number	US-9828495-B2
Application number	US-201414576576-A
Country	US
Kind code	B2
Filing date	Dec 19, 2014
Priority date	Dec 19, 2014
Publication date	Nov 28, 2017
Grant date	Nov 28, 2017

Abstract

Embodiments of a polyethylene polymer blend having a melt index (I 2 )<2 g/10 min are provided, wherein the polyethylene polymer blend comprises at least about 50% by wt. of at least one high density polyethylene resin (HDPE) having a density ≧0.950 g/cm3, a melt index (I 2 )<4 g/10 min; a melt flow ratio (I 10 /I 2 )≦9, and a molecular weight distribution (MWD) of about 2 to about 5; and further comprises about 1% to about 20% by wt. of at least one low density polyethylene resin (LDPE) having a density ≦0.930 g/cm3, a melt index (I 2 ) of about 0.1 to about 10 g/min, and an MWD>3.

First claim

What is claimed is:

1. A polyethylene polymer blend having a melt index (I 2 )<2 g/10 min, wherein I 2 is measured according to ASTM D1238 at 190° C. and 2.16 kg load, wherein the polyethylene polymer blend comprises:
at least about 50% by wt. of at least one high density polyethylene resin (HDPE) having
a density ≧0.950 g/cm 3 , when measured according to ASTM D792;
a melt index (I 2 )<4 g/10 min;
a melt flow ratio (I 10 /I 2 )≦9, where I 10 is measured according to ASTM D1238 at 190° C. and 10 kg load; and
a molecular weight distribution (MWD) of about 2.0 to about 5, wherein MWD is defined as Mw/Mn with Mw being a weight average molecular weight and Mn being a number average molecular weight; and

about 1% to about 20% by wt. of at least one low density polyethylene resin (LDPE) having a density ≦0.930 g/cm 3 , a melt index (I 2 ) of about 0.1 to about 10 g/min, and a MWD>3.

2. The polyethylene polymer blend of claim 1 wherein the polyethylene polymer blend comprises about 2% to about 15% by wt. LDPE.

3. The polyethylene polymer blend of claim 1 wherein the polyethylene polymer blend comprises about 60% to about 98% by wt. HDPE.

4. The polyethylene polymer blend of claim 1 wherein the density of the polyethylene polymer blend ≧0.950 g/cm 3 and the melt flow ratio (I 10 /I 2 ) of the polyethylene polymer blend ≦9.

5. The polyethylene polymer blend of claim 1 wherein the melt index (I 2 ) of the polyethylene polymer blend is from about 0.5 to about 1.5 g/10 min.

6. The polyethylene polymer blend of claim 1 wherein the density of the HDPE is from about 0.955 to about 0.970 g/cm 3 and the MWD of the HDPE is from about 2.5 to about 4.

7. The polyethylene polymer blend of claim 1 wherein the melt index (I 2 ) of the HDPE is from about 0.5 to about 2 g/10 min and the melt flow ratio (I 10 /I 2 ) of the HDPE is from about 6 to about 8.

8. The polyethylene polymer blend of claim 1 wherein the density of the LDPE is from about 0.915 to about 0.930 g/cm 3 , and the MWD of the LDPE is from about 4 to about 10.

9. The polyethylene polymer blend of claim 1 wherein the melt index (I 2 ) of the LDPE is from about 0.5 to about 7 g/10 min.

10. An article comprising a polyethylene polymer blend, wherein the polyethylene blend has a melt index (I 2 )<2 g/10 min, wherein I 2 is measured according to ASTM D1238 at 190° C. and 2.16 kg load, wherein the polyethylene polymer blend comprises:
at least about 50% by wt. of at least one high density polyethylene resin (HDPE) having
a density ≧0.950 g/cm 3 , when measured according to ASTM D792;
a melt index (I 2 )<4 g/10 min;
a melt flow ratio (I 10 /I 2 )≦9, where I 10 is measured according to ASTM D1238 at 190° C. and 10 kg load; and
a molecular weight distribution (MWD) of about 2.0 to about 5, wherein MWD is defined as Mw/Mn with Mw being a weight average molecular weight and Mn being a number average molecular weight; and

about 1% to about 20% by wt. of at least one low density polyethylene resin (LDPE) having a density ≦0.930 g/cm 3 , a melt index (I 2 ) of about 0.1 to about 10 g/min, and a MWD>3, and
wherein the article has a haze value ≦30% when measured according to ASTM-D-1003.

11. The article of claim 10 wherein the article has a 2% secant modulus greater than 90,000 psi in the machine direction in accordance with ASTM D882-12.

12. The article of claim 10 wherein the article has an MD tear of less than 35 g in the machine direction in accordance with ASTM D882-12.

13. The article of claim 10 wherein the article is a blown monolayer film having a thickness of about 0.5 to about 1.5 mils and the haze value ≦25%.

14. The article of claim 13 wherein the haze value ≦20%.

15. The article of claim 10 wherein the polyethylene polymer blend comprises about 2% to about 15% by wt. LDPE, and about 60% to about 98% by wt. HDPE.

16. The article of claim 10 wherein the density of the polyethylene polymer blend ≧0.950 g/cm 3 , the melt flow ratio (I 10 /I 2 ) of the polyethylene polymer blend ≦9, and the melt index (I 2 ) is from about 0.5 to about 1.5 g/10 min.

17. The article of claim 10 wherein the density of the HDPE is from about 0.955 to about 0.970 g/cm 3 and the MWD of the HDPE is from about 2.5 to about 4.

18. The article of claim 10 wherein the melt index (I 2 ) of the HDPE is from about 0.5 to about 2 g/10 min and the melt flow ratio (I 10 /I 2 ) of the HDPE is from about 6 to about 8.

19. The article of claim 10 wherein the density of the LDPE is from about 0.915 to about 0.930 g/cm 3 , the MWD of the LDPE is from about 4 to about 10, and the melt index (I 2 ) of the LDPE is from about 0.5 to about 7 g/10 min.

Assignees

• Dow Global Technologies Llc

Inventors

• Demirors Mehmet
• Bilgen Mustafa
• Lin Yijian

Classifications

• C08L23/06 Primary

  Polyethylene · CPC title

• C08L2203/16

  used for films · CPC title

• C08L2207/068

  Ultra high molecular weight polyethylene · CPC title

• C08L2207/066

  LDPE (radical process) · CPC title

• C08L2205/025

  containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure · CPC title