Process for increasing the melt strength of a polyethylene resin, a masterbatch composition and a polymeric composition

Patent metadata

Field	Value
Publication number	US-9714326-B2
Application number	US-201415023673-A
Country	US
Kind code	B2
Filing date	Sep 18, 2014
Priority date	Sep 30, 2013
Publication date	Jul 25, 2017
Grant date	Jul 25, 2017

Abstract

A process for increasing the melt strength of a polyethylene resin comprising a) selecting a polyethylene resin having i) a density, as determined according to ASTM D792, in the range of from 0.865 g/cm 3 to 0.97 g/cm 3 , and ii) a melt index, I 2 , as determined according to ASTM D1238 (2.16 kg, 190° C.), in the range of from 0.01 g/10 min to 100 g/10 min; b) reacting from 10 ppm to 1000 ppm of at least one peroxide having a 1 hour half-life decomposition temperature from 160° C. to 250° C. with the polyethylene resin under conditions sufficient to increase the melt strength of the polyethylene resin is provided. Also provided are a masterbatch composition and a polymeric composition.

First claim

We claim:

1. A method for increasing the melt strength of a polyethylene resin comprising:
a) selecting up to 99 percent by weight of a polyethylene resin having
i) a density, as determined according to ASTM D792, in the range of from 0.865 g/cm 3 to 0.97 g/cm 3 , and
ii) a melt index, I 2 , as determined according to ASTM D1238 (2.16 kg, 190° C.), in the range of from 0.01 g/10 min to 100 g/10 min;

b) reacting from 10 ppm to 75 ppm of at least one peroxide having a 1 hour half-life decomposition temperature from 160° C. to 250° C. with the polyethylene resin,
wherein the peroxide is added to the polyethylene resin as from 1 to 5 percent by weight of a masterbatch comprising the peroxide along with a carrier resin, and wherein the carrier resin is selected from polyethylenes having a vinyl concentration from 0.07 to 0.7 per 1,000 carbons in the backbone of the polymer, and wherein said at least one peroxide is 3,3,5,7,7-pentamethyl-1,2,4 trioxepane, and wherein the polymeric resin exhibits an increase in melt strength at 100 mm/sec which is at least 20% greater than the melt strength of the polyethylene resin in the absence of the masterbatch.

2. The method according to claim 1 , wherein the ratio of I 2 of the polyethylene resin to the I 2 of the carrier resin is from 0.2 to 5.

3. The method according to claim 1 , wherein the peroxide is present in amounts from 14 to 20 ppm.

4. A polymeric composition comprising:
from 1 to 5 wt % of a masterbatch comprising a carrier resin and from 1000 ppm to 10000 ppm of at least one peroxide having a 1 hr. half-life decomposition temperature from 160° C. to 250° C.;
up to 99 wt % polyethylene resin having
a density, as determined according to ASTM D792, in the range of from 0.865 g/cm 3 to 0.97 g/cm 3 , and
a melt index, I 2 , as determined according to ASTM D1238 (2.16 kg, 190° C.), in the range of from 0.01 g/10 min to 100 g/10 min; and
a vinyl concentration from 0.07 to 0.7 per 1,000; and

wherein the polymeric composition comprises from 10 to 75 ppm said at least one peroxide, wherein said at least one peroxide is 3,3,5,7,7-pentamethyl-1,2,4 trioxepane; wherein the polymeric composition exhibits an increase in melt strength at 100 mm/sec which is at least 20% greater than the melt strength of the polyethylene resin in the absence of the masterbatch.

Assignees

• Dow Global Technologies Llc

Inventors

• Demirors Mehmet
• Ewart Sean W
• Karjala Teresa P
• Pollard Maria

Classifications

• C08K5/14 Primary

  Peroxides · CPC title

• C08K5/0025

  Crosslinking or vulcanising agents; including accelerators · CPC title

• C08L23/04

  Homopolymers or copolymers of ethene · CPC title

• C08J2323/06

  Polyethene · CPC title

• C08L23/06

  Polyethylene · CPC title