Oxygen-scavenging articles devoid of visual spots upon oxidation and related methods

Abstract

A transparent article comprises a thermoplastic polymer matrix and a plurality of domains, dispersed in the thermoplastic polymer matrix and having dimensions in an axial plane of the article, each domain encompassing an oxidizable inorganic composition, wherein the shortest dimension of each domain in the axial plane of the article is up to about 45 microns, so as to substantially preclude visibility of the domains to a naked eye resulting from oxidation of the inorganic composition within the domain as well as oxidation of the inorganic composition that exceeds the domain but does not exceed up to about 45 microns. A method of production of the article is also provided.

What is claimed is:  
     
         1 . A transparent article comprising 
 a thermoplastic polymer matrix; and    a plurality of domains dispersed in the thermoplastic polymer matrix and having dimensions in an axial plane of the article, each domain encompassing an oxidizable inorganic composition, wherein the shortest dimension of each domain in the axial plane of the article is up to about 45 microns, so as to substantially preclude visibility of said domains to a naked eye resulting from oxidation of the inorganic composition within said domain as well as oxidation of the inorganic composition that exceeds the domain but does not exceed up to about 45 microns.    
     
     
         2 . The transparent article of  claim 1 , wherein the transparent article is stretched.  
     
     
         3 . The transparent article of  claim 1 , wherein the transparent article is a plastic bottle.  
     
     
         4 . The transparent article of  claim 1 , wherein the thermoplastic polymer matrix is selected from the group consisting of linear polyesters, branched polyesters, polyamides, polystyrenes, polycarbonates, polyvinylchlorides, polyvinylidene dichlorides, polyacrylamides, polyacrylonitrites, polyvinylacetate, poly acid, polyvinyl methyl ether, ethylene vinyl acetate copolymer, ethylene methyl acrylate copolymer, low molecular weight polyolefins having 2 to 8 carbon atoms, and copolymers and terpolymers thereof, and blends thereof.  
     
     
         5 . The transparent article of  claim 4 , wherein said thermoplastic polymer matrix is a linear polyester matrix selected from the group consisting of polyethylene terephthalate, polyethylene naphthalate, and polybutylene terephthalate, polytrimethylene terephthalate, and copolymers and terpolymers thereof.  
     
     
         6 . The transparent article of  claim 1 , wherein the thermoplastic polymer is polyethylene terephthalate.  
     
     
         7 . The transparent article of  claim 1 , wherein the inorganic oxidizable composition includes an oxidizable metal.  
     
     
         8 . The transparent article of  claim 1 , wherein the inorganic oxidizable composition includes iron.  
     
     
         9 . The transparent article of  claim 1 , wherein the inorganic oxidizable composition includes an oxygen scavenging particle.  
     
     
         10 . The transparent article of  claim 1 , wherein the shortest dimension of each domain is up to about 38 microns.  
     
     
         11 . The transparent article of  claim 1 , wherein the shortest dimension of each domain is up to about 32 microns.  
     
     
         12 . A method for the production of a transparent article including a thermoplastic polymer matrix having an inorganic oxidizable composition dispersed therein, comprising: 
 adding an effective amount of the inorganic oxidizable composition into the polymer matrix to scavenge oxygen passing through the polymer matrix;    forming an article of desired size and shape, wherein domains are created around the inorganic oxidizable composition upon formation of the article, the domains having dimensions in the axial plane of the article, and wherein the shortest dimension of each domain is up to about 45 microns so as to substantially preclude visibility of said domains to the named eye resulting from oxidation of the inorganic composition within said domain as well as oxidation of the inorganic composition that exceeds the domain but does not exceed up to about 45 microns.    
     
     
         13 . The method of  claim 12 , wherein said transparent article is stretched.  
     
     
         14 . The method of  claim 12 , wherein the transparent article is a plastic bottle.  
     
     
         15 . The method of  claim 12 , wherein the inorganic oxidizable composition includes an oxidizable metal.  
     
     
         16 . The method of  claim 12 , wherein the inorganic oxidizable composition includes an iron.  
     
     
         17 . The method of  claim 12 , wherein the step of forming includes blow-molding a container of desired size and shape.  
     
     
         18 . The method of  claim 12 , wherein the thermoplastic polymer matrix is selected from the group consisting of linear polyesters, branched polyesters, polyamides, polystyrenes, polycarbonates, polyvinylchlorides, polyvinylidene dichlorides, polyacrylamides, polyacrylonitrites, polyvinylacetate, poly acid, polyvinyl methyl ether, ethylene vinyl acetate copolymer, ethylene methyl acrylate copolymer, low molecular weight polyolefins having 2 to 8 carbon atoms, and copolymers and terpolymers thereof, and blends thereof.