Analysis of volatile radiolysis products in gamma-irradiated LDPE and polypropylene films by thermal desorption–gas chromatography–mass spectrometry

Antioxidants and their migration into food simulants on irradiated LLDPE film

“…The migration levels of the Irganox 1076 into distilled water, acetic acid (4 ml/100 ml distilled water) or ethanol (20 ml/100 ml distilled water) were decreased with increasing g-irradiation, respectively. After migrating from the LLDPE into food simulants, the migrated compounds decompose into a number of unknown products (Buchalla, Boess, & Bo¨gl, 2000). It is assumed that the decomposition of antioxidants in aqueous food simulants was enhanced by degradation besides by radiolysis.…”

Effect of ionizing radiation on physicochemical and mechanical properties of commercial monolayer and multilayer semirigid plastics packaging materials

“…Antioxidants were incorporated into polyolefins diminish the rate of oxidation, but as irradiation proceeds the antioxidants degrade because of partial radiolysis (Bourges et al, 1992;Buchalla et al, 2000). The extent of degradation of antioxidants depends on the nature of both the antioxidant and the polymer, the radiation dose and dose rate, and the crystallinity of the polymer (Wilski, 1987;Allen et al, 1991;Bourges et al, 1992Bourges et al, , 1993Dole, 1991;Buchalla et al, 1997Buchalla et al, , 2000Marque et al, 1998). The lower the polymer crystallinity, the higher the oxidation potential, since oxygen cannot penetrate the crystalline regions of polymers (Dole, 1991;Kashiwabara et al, 1991;Jahan et al, 2001).…”

Radiation treatment for sterilization of packaging materials

“…Packaging materials in contact with the product should be compatible with irradiation and the product (e.g. should not undergo significant alteration of their functional properties as a result of irradiation at the doses required, nor yield toxic materials which can transfer to the dried products) (Buchalla et al, 2000). Polyethylene, polypropylene, biaxially oriented polypropylene (BOPP), or other clear flexible materials of similar qualities may be used for packaging.…”

“…The low-molecular-weight radiolysis products are retained for considerable times in LDPE films and they are retained in PP films much longer than had been expected. Besides product identification, the following are important topics to be addressed: effects of the absorbed dose and the desorption temperature; comparison of several commercial (proprietary) films; high-temperature thermal desorption (TDS); the question whether TDS analyzes radiation-induced artifacts rather than genuine products; the possible existence of cyclic radiolysis products; the possibility of identifying an LDPE as irradiated after a dose of only 1 kGy; and a typical trace fragment of antioxidants (Buchalla et al, 2000). Thompson et al (1997) investigated such migration into four standard product simulates: acetic acid, ethanol, olive oil, and deionized water.…”