Degradation of pullulan irradiated in hydro-methanolic blends: Influence of cinnamyl alcohol at low absorbed dose of radiation

Dhriti Khandal; Xavier Coqueret

doi:10.1016/j.carbpol.2020.116808

Degradation of pullulan irradiated in hydro-methanolic blends: Influence of cinnamyl alcohol at low absorbed dose of radiation

Carbohydr Polym. 2020 Nov 15:248:116808. doi: 10.1016/j.carbpol.2020.116808. Epub 2020 Jul 25.

Authors

Dhriti Khandal¹, Xavier Coqueret²

Affiliations

¹ Institut de Chimie Moléculaire de Reims, CNRS UMR 7312, Université de Reims Champagne Ardenne, 51687 Reims, France.
² Institut de Chimie Moléculaire de Reims, CNRS UMR 7312, Université de Reims Champagne Ardenne, 51687 Reims, France. Electronic address: xavier.coqueret@univ-reims.fr.

PMID: 32919541
DOI: 10.1016/j.carbpol.2020.116808

Abstract

This study reports on the effects of electron beam radiation on pullulan in both the dry state and hydro-methanolic blends containing cinnamyl alcohol (CA). The radiation chemical yields of scission (G(S)) and crosslinking (G(X)) were determined using Saito's formalism applied to the evolution of molecular weight (MW) with increasing absorbed dose of radiation. To satisfy the requirements of the statistical treatment, commercially available pullulan was fractionated to obtain a monomodal MW distribution with a dispersity close to 2. The changes in MW profiles were monitored by SEC with differential refractive index and UV detection. The introduction of small quantities of CA in the pullulan blends led to a significant decrease in G(S) and G(X), protecting pullulan against radiation-induced effects likely via energy and electron transfer. In presence of larger amounts of CA, irradiation at higher dose induced an increase in molecular mass with concomitant grafting of the aromatic additive.

Keywords: Cinnamyl alcohol; Crosslinking; Pullulan; Radiation protection; Radiolytic yields; Scission.