Packaging materials
The use of a palladium-doped zeolite for the adsorption of volatile organic compounds is described wherein the zeolite has a CHA framework type and is polymer-bound. Such zeolites have been found to have particular utility as packaging materials for the adsorption of volatile organic compounds, such as those originating from organic matter.
1. A packaging material for the adsorption of volatile organic compounds, the material comprising a polymer film with a coating on the surface of the polymer film, wherein the coating comprises particles of a palladium-doped zeolite and a polymeric binder, wherein the zeolite has a chabazite framework type.
2. The packaging material according to claim 1 , wherein the polymer film is selected from an ethylene vinyl acetate film, a low-density polyethylene film, a high-density polypropylene film, a polypropylene film, or a high impact polystyrene film.
3. The packaging material according to claim 1 wherein the zeolite comprises 0.2 to 2 wt % palladium based on the total weight of doped zeolite.
4. The packaging material according to claim 1 wherein the zeolite has a silica to alumina molar ratio (SAR) of less than or equal to 100:1.
5. A packaging material according to claim 1 , wherein the packaging material comprises a single polymer film layer which has the coating applied on one surface of the film.
6. A packaging material according to claim 1 , wherein the packaging material comprises a single polymer film layer which has the coating applied on both surfaces of the film.
7. A packaging structure comprising a packaging material according to claim 1 .
8. The packaging material according to claim 1 wherein the palladium-doped zeolite is in the hydrogen form.
9. An ink for application to a packaging material, the ink comprising palladium-doped zeolite particles and a polymeric binder, wherein the zeolite has a chabazite framework type.
10. An ink according to claim 9 , wherein said polymeric binder is water-soluble and a weight ratio of palladium-doped zeolite to water-soluble binder is 3:1 to 19:1.
11. A method of adsorbing volatile organic compounds using a palladium-doped zeolite, wherein the zeolite has a chabazite framework type and is polymer-bound.
12. The method according to claim 11 wherein the volatile organic compounds originate from organic matter.
13. The method according to claim 11 wherein particles of the palladium-doped zeolite are dispersed within a polymeric packaging material.
14. The method according to claim 11 wherein particles of the palladium-doped zeolite are incorporated in a coating on a surface of a polymeric packaging material, the coating comprising a polymeric binder and the palladium-doped zeolite particles.
15. The method according to claim 11 wherein the volatile organic compound is ethylene.