Improving the Gas-Fading Performance of Polyethylene Film Resins by Addressing the Over-Oxidation of Phenolic Antioxidants, 2005 PLACE Conference
Discoloration of polyethylene due to “gas-fading” is an ongoing nuisance in the film packaging industry and can result in significant product claims and potential loss of business. It is well known that gas-fading can be attributed to the over-oxidation of phenolic antioxidants. There is a correlation between the changes in color that can occur during processing and the subsequent discoloration due to gas-fading. NOVA Chemicals has recently introduced gas-fade resistant polyethylene film resins into the marketplace. Data comparing the melt flow and color stability, physical property performance, long-term thermal stability and improved gas-fading resistance of these resins to conventionally stabilized formulations are presented. The new resins have been designed to tolerate the addition of moderate levels of phenolic antioxidant (from blending with other film resins) without a significant effect on color performance.