Oxygen scavenger system in a polyolefin matrix
View Patent ↗An oxygen scavenging polyolefin composition and methods of making thereof are described herein. In one approach, the composition includes a continuous non-polar polyolefin matrix having oxygen scavenging domains dispersed therein. The oxygen scavenging domains include an oxidizable polymer, a transition metal catalyst or salt thereof, and a catalytic promoter effective to bind with oxygen passing through the continuous non-polar polyolefin matrix. The oxygen scavenging domains forming a discrete polar region within the continuous non-polar polyolefin matrix. The composition further includes a polymeric compatibilizer having a polar moiety and a non-polar moiety and in amounts effective to uniformly disperse the polar oxygen scavenging domains in the continuous non-polar polyolefin matrix.
1. An oxygen scavenging polymer composition comprising:
a continuous non-polar polymer composition including a polyolefin;
oxygen scavenging domains dispersed in the continuous non-polar polymer composition, the oxygen scavenging domains including an oxidizable polymer, a transition metal catalyst or salt thereof, and a source of N-oxyl radicals effective to bind with oxygen passing through the continuous non-polar polymer composition, the oxygen scavenging domains containing polar regions within the continuous non-polar polymer composition; and
a polymeric compatibilizer in the continuous non-polar polymer composition, the polymeric compatibilizer having a polar moiety and a non-polar moiety and in amounts effective to uniformly disperse the polar oxygen scavenging domains in the continuous non-polar polymer composition.
2. The oxygen scavenging polymer composition of claim 1 , wherein the amount of the polymeric compatibilizer is effective to form the oxygen scavenging domains of about 15 nm to about 10 microns in size.
3. The oxygen scavenging polymer composition of claim 1 , wherein the amount of polymeric compatibilizer is effective to form about 100 to about 400 oxygen scavenging domains per about 500 to about 1000 square microns of the continuous non-polar polymer composition.
4. The oxygen scavenging polymer composition of claim 1 , wherein the polymeric compatibilizer has about 0.1 to about 6 percent of a polar moiety grafted on a non-polar polymeric backbone.
5. The oxygen scavenging polymer composition of claim 1 , wherein the polymeric compatibilizer has a non-polar polyolefin backbone and a grafted carboxylic acid group thereon forming the polar moiety.
6. The oxygen scavenging polymer composition of claim 1 , wherein the polymeric compatibilizer is maleic anhydride grafted polyolefin.
7. The oxygen scavenging polymer composition of claim 6 , wherein the maleic anhydride grafted polyolefin includes about 0.2 to about 2 percent maleic anhydride.
8. The oxygen scavenging polymer composition of claim 1 , wherein the oxidizable polymer is a base polymer with repeating alkyl groups substituted with a cyclic amide.
9. The oxygen scavenging polymer composition of claim 8 , wherein the oxidizable polymer is polyvinylpyrrolidone.
10. The oxygen scavenging polymer composition of claim 1 , wherein the transition metal catalyst or salt thereof is cobalt neodecanoate.
11. The oxygen scavenging polymer composition of claim 1 , wherein the source of N-oxyl radicals is a hydroxyimide compound.
12. The oxygen scavenging polymer composition of claim 1 , wherein the source of N-oxyl radicals is n-hydroxyphthalimide.
13. The oxygen scavenging polymer composition of claim 1 , wherein the source of N-oxyl radicals is an ester of a hydroxyimide effective to withstand temperatures of up to about 230° C.
14. The oxygen scavenging polymer composition of claim 1 , wherein the source of N-oxyl radicals is an ester of hydroxyimide including an acetoxy derivative of n-hydroxyphthalimide.
15. The oxygen scavenging polymer composition of claim 14 , wherein the ester of hydroxyimide includes n-hydroxyphthalimide acetate.