Impact of γ-irradiation, ageing and their interactions on multilayer films followed by AComDim

Abstract

To highlight the main factors involved in the degradation of polymers in multilayer films under γ-irradiation, the ANOVA Common Dimensions (AComDim, Analysis of Variance in Common Dimensions) method is applied on spectra recorded with ATR-FTIR (Attenuated Total Reflection-Fourier Transform Infrared). The present study focuses on the stability of γ-irradiated polymers used in single-use plastic bags made of multilayer films for the biopharmaceutical and biotechnological industries. The samples are irradiated at several γ-doses, up to 270 kGy, and compared with a non-irradiated sample used as reference. It shows that the γ-dose, the natural ageing up to six months and the γ-dose × ageing interaction are the most influential factors.

Infrared spectroscopy as a useful tool to predict land use depending on Mediterranean contrasted climate conditions: A case study on soils from olive-orchards and forests

“…By examining the calculated saliences, it is possible to determine which CC is related to which factor or interaction In order to estimate the effect of the factor, it is possible to plot the sample scores on the informative CCs vs. CC1. Loadings show spectral bands discriminating samples for a CC and are used to understand sample projections on the score graphs (Gaston et al, 2017). All the spectral bands were assigned according to Socrates (2007).…”

Monitoring of the discoloration on γ‐irradiated PE and EVA films to evaluate antioxidant stability

“…Infra-red Samples were directly deposited onto the Bruker "Golden Gate" attenuated total reflectance (ATR) accessory provided with a diamond crystal. The spectra for each film sample were recorded from 4000 to 650 cm 21 , with 4 cm 21 resolution and 64 scans, on a Thermo Nicolet Avatar spectrometer equipped with a MCT/A detector, an Ever-Glo source, and a KBr/germanium beam splitter. The spectrometer was placed in an airconditioned room at 21 8C.…”

“…The spectroscopic study ( Figure 5) shows there is no difference between non-irradiated and irradiated AOs indicating that the quantity of transformed molecules is weak and below the sensitivity of this spectroscopic method (<2%). In the Fourier transform infrared (FTIR) spectra, there is no apparition or no evolution of the carbonyl band at 1730-1760 cm 21 , which is a key moiety in the colored molecules (Supporting Information Figures 1 and 2). The number of colored molecules formed and thereof the corresponding number of radicals at the origin of their formation is weak in accordance with the ESR signal.…”

“…Previous studies have likewise shown that plastic film which is the main part constituting the single use devices can undergo oxidation leading to the creation of carboxylic acids, ketones, and other oxygenated species without structural damage. [19][20][21] This oxidation and the color change are inherent to polymers under g-irradiation and cannot be avoided, whatever the stabilization package incorporated into the polymers. It is thereof crucial to identify the phenomena responsible of the discoloration and to apprehend the Additional Supporting Information may be found in the online version of this article.…”

Reconciliation of pH, conductivity, total organic carbon with carboxylic acids detected by ion chromatography in solution after contact with multilayer films after γ-irradiation

“…In this study, γ-irradiation doses investigated are up to 270 kGy in order to emphasize the γ-irradiation effect and to better investigate the modifications of commercial PE(Polyethylene)/EVOH(Ethylene Vinyl Alcohol)/PE-film and commercial EVA(Ethylene Vinyl Acetate)/ EVOH/EVA film from three different batches, respectively. This study is a part of a global investigation on γ-irradiation on multilayer films (Audran et al, 2015;Gaston et al, 2016a;Gaston et al, 2016b;Gaston et al, 2017). Non-specific (TOC, pH, conductivity) or specific (e.g.…”