INVESTIGATION OF THE OXYGEN DEPLETION PROPERTIES OF ETHYLENE VINYL ACETATE RESINS FILLED WITH NOVEL OXYGEN SCAVENGERS

The tensile and oxygen depletion properties of EVA resins blended with varying compositions of iron (Fe), modified iron (MFe) and/or ascorbic acid (Vc) oxygen scavengers were systematically investigated. Oxygen depletion experiments clearly suggest that the oxygen depletion rates of modified iron powders filled E MFe series samples are much faster than those of E vc and E Fe series samples filled with the same weight loadings of ascorbic acid and pure iron powders, respectively. After blending Vc together with MFe oxygen scavenger compounds in the EVA resins, a "synergistic" effect on the oxygen depletion properties of the E VcMFe samples was observed when the weight ratios of Vc to MFe oxygen scavengers are between 3/7 to 5/5. Further tensile experiments show that, E Fe and E MFe series samples always exhibit significantly higher of and e f values than E vc series samples filled with the same oxygen scavenger contents. In fact, the σ f and e f values of the E VcMFe series samples increase significantly as their Vc loadings present in oxygen scavenger compounds reduce. In order to understand these interesting oxygen depletion and tensile properties of E Vc , E Fe , E MFe and E VcMFe series samples, SEM and EDX analysis of the compositions on the surfaces of E VcMFe series samples were performed. Possible mechanisms accounting for these interesting oxygen depletion and tensile properties of E Vc , E Fe , E MFe and E VcMFe series samples are proposed.