Study on The Gas Permeability Characteristics of Plastic Film for Packaging of Fresh Produce

Abstract

Currel?t attempts of understanding and nzodeling of the cfvnanzic process in a filn~ plastic packaging nre hantpered by a lack of data in sonre cases. il.foOd~at ta on .filin pernieability have been generated at a single temperature. Current informarion suggests that temperature has an effect on gns pernteability of plastic )film. Furthernzore, perntenbilitv of plastic Jil171to tliferelzt gases changes &J qfSerent amouizts in response to tentperature changes. The m~nilabilin;o f gas permeabilitv data qf plastic film at several temperatures will help the researcher to design t/7e storage of .fie& produce. Likewise, it will help to make any mathenratical model more accurate. A steady state concentration increase method ~rjast ?evelopedf or the measurenzenF of pernrenbilih, of plastic fifilnz to ovgen, carbon dioxide, and nitrogen simuitnneorr.s(v. T17e apparatus con.rist.~o f a pernzeability cell with three chatnbers separated by the rest j5ln1, gas qiinders, pressure regulators, toggle valves, needle valves, solenoid valves, inassflo~tm~e ter, relqv ERB-24, PIO-12 itztet-face cart/, IRiM PC, and gas chror?rntograph with TCD detector. A plasficjlm of JSR RB-820 with 20 ,unz thickne.ss made by Japan 'Svnthetic Rubber Co., was tested using this instrument. The perineabilities of plastic film to carbon dioxide, oxygen, and nitrogen were measured at 5, 15, 25, and 35 "C. The results show that the temperature has a sign!ficarzt eflect on perineabilities of all gases tested. The tentperature effect on gas permeahilitv can be expressed by an Arrhenius equation as follolvs : Oxygei? pernzeabili9 P = 1.76 Exp (-4090/T) R = 0.995 Carbo~zdioxidep ermeability P = 1.17 lo9E xp (-4038/T) R = 0.992 Nitrogen pernzeability P = 8.75 1 0 % ~(-2~67 017) R = 0.94 1