This study evaluates thermoformed trays as used in the food service industry. The resin used in fabricating trays is a blend of Acrylonitrile Butadiene Styrene (ABS) and Polycarbonate (PC). The life of the trays is presently between 1 to 3 years. The trays are used in correctional facilities and hospitals. The handling of the tray is not abusive. The trays are pulled out of service once they exhibit stress cracking. To further understand the unpredictable life of the thermoformed trays an understanding of the behavior of the plastics is required and the method of comparing one resin from another, as used in industry. The actual process used in manufacturing the trays will also indicate where potential problems could cause failure in the trays. Most importantly, the environment, such as, exposure to solvents and boiling water is studied. The most significant element that curtails the life of the trays is the solvent or rinsing agent used in the automatic dishwashers for cleaning the trays. Recycling of the ABS/PC blend could also cause premature failure in the trays.
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