This study addresses a specific problem faced by a company in the food industry, although all food companies face similar issues. In an effort to reduce costs, the pursuit to down-gauge packaging materials is constant. In the case of this study, the primary package of a dairy product is being considered for reduction from the current 57 mil thickness to 52 mils. In the past, as the material was down-gauged from 62 mils, a loss in material strength and an increase in damage were observed. Initial research into the issue by line personnel found that the increase in damage was occurring when the forming equipment stopped running and material was held in the hydrogen peroxide (H202) and heating tunnels for extended amounts of time. Further investigation confirmed that extended durations of the material submerged in the H202 sterilization tank caused the material to embrittle. Therefore, this study was constructed to determine the effects of H202 on two materials, polystyrene and polypropylene, and at two thickness', 57 and 52 mils, and 55 and 50 mils, respectively. The materials were exposed to increasing durations of H202, 0 time, 20 seconds, 60 seconds, 120 seconds, 300 seconds, 600 seconds, 1200 seconds, and subsequently tested for tensile strength, elongation, and modulus of elasticity. It was expected that these properties would decrease as the exposure was increased, but the results did not demonstrate that. The polystyrene based material exhibited very little, or no, change in mechanical properties that could be attributed to H202. Indications were that any variations in mechanical properties were based more on other factors, such as materials impurities or variations in the extrusion process, than the exposure to H202. The polypropylene based material did exhibit some relation between material properties and exposure to H202. Although these changes were very small and left significant doubt as to their negative impact in the aseptic process.
Library of Congress Subject Headings
Plastics in packaging--Research; Food|xPackaging--Research; Polymers--Mechanical properties--Research; Polypropylene; Polystyrene; Hydrogen peroxide
Department, Program, or Center
Manufacturing and Mechanical Engineering Technology (CAST)
Torres, John, "Mechanical properties of polystyrene and polypropylene based materials after exposure to hydrogen peroxide" (1999). Thesis. Rochester Institute of Technology. Accessed from
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