Cyclic-diene additives in polyethylene films and enhanced film orientation balance in production thereof

Patent metadata

Field	Value
Publication number	US-10124528-B2
Application number	US-201515303788-A
Country	US
Kind code	B2
Filing date	May 14, 2015
Priority date	May 29, 2014
Publication date	Nov 13, 2018
Grant date	Nov 13, 2018

Abstract

A method of forming a blown film comprising extruding a molten composition through a die opening to form a film; wherein the molten composition comprises at least one polyethylene and within the range from 0.10 wt % to 10 wt % of a cyclic-diene terpolymer by weight of the composition; causing the film to progress in a direction away from the die opening; cooling the film at a distance from the die opening, the distance adjusted to effect the properties of the film; and isolating a blown film therefrom.

First claim

The invention claimed is:

1. A blown film having an MD Tensile Strength within a range from 6,000 psi (41 MPa) to 16,000 psi (110 MPa) comprising:
a composition comprising at least one polyethylene and within the range from 0.10 wt % to 10 wt % of a cyclic-diene terpolymer (CDTP); wherein the CDTP comprises ethylene-derived units, within a range from 0.01 wt % to 10.0 wt % cyclic diene-derived units, and 0 wt % to 20 wt % of C 4 to C 10 α-olefin derived units based on the weight of the CDTP, wherein the CDTP has:
a) a g′ vis of less than 0.80;
b) an M w(MALLS) within a range of from 200,000 g/mol to 1,000,000 g/mol;
c) an M w(MALLS) /M n(DRI) within the range of from 5.0 to 30.0; and
d) an M z(MALLS) /M n(DRI) of greater than 50.0;

wherein the blown film follows the relationship:
20,676 (psi)<ASC-44094· f LAM <24,676 (psi);

wherein f LAM is the Orientation of lamellae stacks to MD in MD-TD plane [-], and ASC is the 1% Average Secant Flexural Modulus [psi].

2. The blown film of claim 1 , achieved at a Maximum Die Rate of greater than 13 lb/in-hr (0.73 kg/mm-hr).

3. The blown film of claim 1 , wherein the cyclic diene-derived units are selected from the group consisting of dicyclopentadiene (DCPD), norbornadiene (NBD), 5-vinyl-2-norbornene (VNB), ethylidene norbornene (ENB), derivatives thereof, and combinations thereof.

4. The blown film of claim 1 , wherein the polyethylene has a melt index (ASTM D 1238 190° C., 2.16 kg) within the range from 0.20 g/10 min to 10 g/10 min.

5. The blown film of claim 1 , wherein the polyethylene has a g′ vis of greater than 0.90.

6. The blown film of claim 1 , wherein the blown film follows the relationship:
667 (g/mil)<DI+27.8· f c ·100<1,067 (g/mil);

wherein f c is Orientation of c-axis of crystal [-], and DI is Dart Impact [g/mil].

Assignees

• Exxonmobil Chemical Patents Inc

Inventors

• Ravishankar Periagaram S
• Cheng Jianya
• Silva Adriana S
• Li Wen
• Sahnoune Abdelhadi
• Leyva Arturo
• Norman Alexander I

Classifications

• C08J5/18

  Manufacture of films or sheets · CPC title

• B29K2023/06

  PE, i.e. polyethylene · CPC title

• B29K2995/0077

  Yield strength; Tensile strength · CPC title

• B29K2995/0063

  Density · CPC title

• B29C55/28

  of blown tubular films, e.g. by inflation {(extrusion moulding of tubular films B29C48/03)} · CPC title