Oxygen-scavenging materials and articles formed therefrom
View Patent ↗An oxygen-scavenging composition is provided that includes an oxygen-scavenging component and a catalyst. The oxygen-scavenging component, which in preferred embodiments is suitable for use in packaging articles, includes two or more oxygen-scavenging groups having different scavenging properties. In one embodiment, one of the oxygen-scavenging groups is an unsaturated bicyclic group.
1. A composition comprising:
an oxygen-scavenging component including:
a polyamide polymer having a polyamide oxygen-scavenging group, and
a polyester polymer having a condensation backbone and a bicyclic oxygen-scavenging group having at least one double bond located between atoms of a ring,
wherein the polyamide polymer constitutes from about 0.5 to about 5 wt-% of the composition, and the polyester polymer constitutes from about 0.25 to about 2 wt-% of the composition; and
an oxidation catalyst.
2. The composition of claim 1 , wherein the polyamide oxygen-scavenging group and the bicyclic oxygen-scavenging group are present on different polymers.
3. The composition of claim 1 , wherein the bicyclic group comprises a structure represented by the nomenclature expression:
bicyclo[x,y,z]alkene;
wherein:
x is 2 or more, and
y and z are each at least 1.
4. The composition of claim 3 , wherein:
x is 2 or 3, and
y and z are independently 1 or 2.
5. The composition of claim 1 , wherein the bicyclic group comprises bicyclo[2.1.1]hexene, bicyclo [2.2.1]heptene, bicyclo[2.2.1]heptadiene, bicyclo [2.2.2]octene, bicyclo[2.2.2]octadiene, or a mixture thereof.
6. The composition of claim 1 , wherein the concentration of the polyamide polymer in the composition is greater than the concentration of the polyester polymer.
7. The composition of claim 1 , wherein the polyester polymer comprises polyethylene terephthalate.
8. The composition of claim 1 , wherein the bicyclic group comprises a pendant group attached to the condensation backbone.
9. The composition of claim 8 , wherein the pendant group is a reaction product of ingredients including an unsaturated fatty acid.
10. The composition of claim 1 , wherein the polyamide group comprises a structural unit represented by the below structural formula (I):
-arylene-C(HR 1 )—N(R 2 )—(C═O)—,
wherein R 1 and R 2 independently denote one of a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted alkenyl or cycloalkenyl group.
11. The composition of claim 1 , wherein the composition comprises at least about 25 parts per million of the oxidation catalyst.
12. The composition of claim 11 , wherein the oxidation catalyst comprises one or more transition metals, transition metal complexes, or mixtures thereof.
13. The composition of claim 1 , wherein the oxidation catalyst comprises a cobalt catalyst.
14. A packaging article, comprising the composition of claim 1 .
15. The packaging article of claim 14 , wherein the article comprises a single-layer packaging article.
16. The packaging article of claim 14 , wherein the packaging article comprises a multi-layer packaging article.
17. The packaging article of claim 14 , wherein the article comprises about 15 wt-% or less of the oxygen-scavenging component.
18. A method, comprising:
providing:
a conjugated diene component, and
an unsaturated component;
forming a first oxygen-scavenging polyester having a condensation backbone and that includes a bicyclic group that is a Diels-Alder reaction product of the above components, wherein the bicyclic group includes at least one ring having a double bond located between atoms of the ring; and
forming an oxygen-scavenging composition that comprises:
(i) the first oxygen-scavenging polyester;
(ii) a second oxygen-scavenging polymer having at least one of:
(a) a structural unit represented by the below structural formula (I):
-arylene-C(HR 1 )—N(R 2 )—(C═O)—,
wherein R 1 and R 2 independently denote one of a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted alkenyl or cycloalkenyl group; or
(b) an unsaturated oxygen-scavenging group that includes at least one carbon-carbon double bond with a heat of hydrogenation of less than or equal to that of cyclohexene; and
(iii) an oxidation catalyst;
wherein the first oxygen-scavenging polyester constitutes from about 0.25 to about 2 wt-% of the oxygen-scavenging composition, and the second oxygen-scavenging polymer constitutes from about 0.5 to about 5 wt-% of the oxygen-scavenging composition.
19. A composition comprising:
an oxygen-scavenging component that includes:
a first oxygen-scavenging polyester having a condensation backbone and comprising a cyclic or bicyclic oxygen-scavenging group having at least one carbon-carbon double bond located between atoms of a ring, wherein:
the carbon-carbon double bond has a heat of hydrogenation of at least 33 kcal/mole, and
a second oxygen-scavenging polymer comprising:
(i) one or more of a structural unit represented by the formula:
-arylene-C(HR 1 )—N(R 2 )—(C═O)—,
wherein R 1 and R 2 independently denote one of a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted alkenyl or cycloalkenyl group, or
(ii) an unsaturated oxygen-scavenging group that includes at least one carbon-carbon double bond with a heat of hydrogenation of 32 kcal/mole or less; and
an oxidation catalyst;
wherein the first oxygen-scavenging polyester constitutes from about 0.25 to about 2 wt-% of the oxygen-scavenging composition, and the second oxygen-scavenging polymer constitutes from about 0.5 to about 5 wt-% of the oxygen-scavenging composition.
20. The composition of claim 19 , wherein the second oxygen-scavenging polymer comprises one or more of the structural unit represented by the formula -arylene-C(HR 1 )—N(R 2 )—(C═O)—.