Colored oxygen scavenging polymers
View Patent ↗The present invention relates to a melt blend of a base polymer, an oxidizable organic polymer, a transition metal salt catalyst and a colorant that does not completely deactivate the catalyzed oxidation. A preferred colorant, yields in an article made from the polymer melt blend a Catalyst Deactivation Factor (CDF) of less than about 0.25, preferably less than 0.15, more preferably less than 0.1, and most preferred less than 0.05. The present invention also comprises a colored monolayer article having the described CDF, such as a film, thermoformed tray, or blow molded container, that has active oxygen scavenging properties. The colorant, after melt blending a base polymer, an oxidizable organic polymer, a transition metal catalyst, does not increase the binding energy of the transition metal catalyst ion by more than 1 eV.
1. A melt blended resin for packaging articles comprising: a base polymer, oxidizable organic polymer, transition metal catalyst, and a colorant, such that an article made from said melt blended resin has a catalyst deactivation factor of less than 0.25, and further wherein said base polymer is selected from the group consisting of polyethylene, polyester, polyvinyl chloride, polyvinylidene chloride, ethylene copolymers, and blends thereof.
2. The melt blended resin of claim 1 , wherein said colorant does not increase the binding energy of the transition metal catalyst ion by more than 1 eV.
3. The melt blended resin of claim 1 , wherein said base polymer is polyester.
4. The melt blended resin of claim 3 , wherein said polyester is a copolyester of polyethylene terephthalate.
5. The melt blended resin of claim 1 , wherein said oxidixable organic polymer is a partially aromatic polyamide.
6. The melt blended resin of claim 5 , wherein said partially aromatic polyamide is MXD6.
7. The melt blended resin of claim 1 , wherein said oxidizable organic polymer is polybutadiene.
8. The melt blended resin of claim 1 , wherein said transition metal catalyst is a cobalt salt.
9. The melt blended resin of claim 8 , wherein said cobalt salt is cobalt stearate.
10. The melt blended resin of claim 1 , wherein said resin contains an ionic compatibilizer, wherein the ionic compatiblizer reduces the haze of the packaging articles.
11. The melt blended resin of claim 10 , wherein said compatibilizer is a copolyester containing a metal sulfonate salt.
12. The melt blended resin of claim 11 , wherein said metal sulfonate salt is 5-sodiumsulfoisophthalic acid.
13. A monolayer film, having an oxygen permeation rate of less than 0.01 (cc(stp)·cm)/(m2·atm·day), said film formed from a melt blend of a base polymer, oxidizable organic polymer, transition metal catalyst, and a colorant, wherein said base polymer is selected from the group consisting of polyethylene, polyester, polyvinyl chloride, polyvinylidene chloride, ethylene copolymers, and blends thereof.
14. A polymer blend for packaging articles comprising: a melt blend of a base polymer, oxidizable organic polymer, transition metal catalyst, and a colorant, such that said blend does not increase the binding energy of the transition metal catalyst ion by more than 1 eV, and further wherein said base polymer is selected from the group consisting of polyethylene, polyester, polyvinyl chloride, polyvinylidene chloride, ethylene copolymers, and blends thereof.
15. The polymer blend of claim 14 , wherein said blend has a catalyst deactivation factor of less than about 0.25.