On the Mechanism of Electron Beam Radiation-Induced Modification of Poly(lactic acid) for Applications in Biodegradable Food Packaging

Eleanor C. Grosvenor; Justin C. Hughes; Cade W. Stanfield; Robert L. Blanchard; Andrea C. Fox; Olivia L. Mihok; Kristen Lee; Jonathan R. Brodsky; Ann Hoy; Ananya Uniyal; Sydney M. Whitaker; Chris Acha; Kalina Gibson; Lilly Ding; Catherine A. Lewis; Lorelis González López; Charlotte M. Wentz; Lawrence R. Sita; Mohamad Al-Sheikhly

doi:10.3390/app12041819

Applied Sciences (Feb 2022)

On the Mechanism of Electron Beam Radiation-Induced Modification of Poly(lactic acid) for Applications in Biodegradable Food Packaging

Eleanor C. Grosvenor,
Justin C. Hughes,
Cade W. Stanfield,
Robert L. Blanchard,
Andrea C. Fox,
Olivia L. Mihok,
Kristen Lee,
Jonathan R. Brodsky,
Ann Hoy,
Ananya Uniyal,
Sydney M. Whitaker,
Chris Acha,
Kalina Gibson,
Lilly Ding,
Catherine A. Lewis,
Lorelis González López,
Charlotte M. Wentz,
Lawrence R. Sita,
Mohamad Al-Sheikhly

Affiliations

Eleanor C. Grosvenor: Gemstone Honors Program, University of Maryland, College Park, MD 20742, USA
Justin C. Hughes: Gemstone Honors Program, University of Maryland, College Park, MD 20742, USA
Cade W. Stanfield: Gemstone Honors Program, University of Maryland, College Park, MD 20742, USA
Robert L. Blanchard: Gemstone Honors Program, University of Maryland, College Park, MD 20742, USA
Andrea C. Fox: Gemstone Honors Program, University of Maryland, College Park, MD 20742, USA
Olivia L. Mihok: Gemstone Honors Program, University of Maryland, College Park, MD 20742, USA
Kristen Lee: Gemstone Honors Program, University of Maryland, College Park, MD 20742, USA
Jonathan R. Brodsky: Gemstone Honors Program, University of Maryland, College Park, MD 20742, USA
Ann Hoy: Gemstone Honors Program, University of Maryland, College Park, MD 20742, USA
Ananya Uniyal: Gemstone Honors Program, University of Maryland, College Park, MD 20742, USA
Sydney M. Whitaker: Gemstone Honors Program, University of Maryland, College Park, MD 20742, USA
Chris Acha: Gemstone Honors Program, University of Maryland, College Park, MD 20742, USA
Kalina Gibson: Gemstone Honors Program, University of Maryland, College Park, MD 20742, USA
Lilly Ding: Gemstone Honors Program, University of Maryland, College Park, MD 20742, USA
Catherine A. Lewis: Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA
Lorelis González López: Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA
Charlotte M. Wentz: Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA
Lawrence R. Sita: Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA
Mohamad Al-Sheikhly: Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA

DOI: https://doi.org/10.3390/app12041819
Journal volume & issue: Vol. 12, no. 4
p. 1819

Abstract

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Poly(lactic acid) (PLA) is a biodegradable polymer used for food packaging. The effects of electron beam radiation on the chemical and physical properties of amorphous PLA were studied. In this study, amorphous, racemic PLA was irradiated at doses of 5, 10, 15, and 20 kGy in the absence of oxygen. Utilizing electron paramagnetic resonance spectrometry, it was found that alkoxyl radicals are initially formed as a result of C-O-C bond scissions on the backbone of the PLA. The dominant radiation mechanism was determined to be H-abstraction by alkoxyl radicals to form C-centered radicals. The C-centered radicals undergo a subsequent peroxidation reaction with oxygen. The gel permeation chromatography (GPC) results indicate reduction in polymer molecular mass. The differential scanning calorimetry and X-ray diffraction results showed a subtle increase in crystallinity of the irradiated PLA. Water vapor transmission rates were unaffected by irradiation. In conclusion, these results support that irradiated PLA is a suitable material for applications in irradiation of food packaging, including food sterilization and biodegradation.

Published in Applied Sciences

ISSN: 2076-3417 (Online)
Publisher: MDPI AG
Country of publisher: Switzerland
LCC subjects: Technology: Engineering (General). Civil engineering (General); Science: Biology (General); Science: Physics; Science: Chemistry
Website: http://www.mdpi.com/journal/applsci

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