Comparison of gamma radiation crosslinking and chemical crosslinking on properties of methylcellulose

Abstract

This research aims to modify properties, particularly biodegradability, of methylcellulose (MC), by utilizing two crosslinking methods. The first method is gamma irradiation treatment to form insoluble MC gel by intermolecular crosslinking. The second one is the use of a glutaraldehyde (GA) crosslinker to promote hemi-acetal linkages between MC polymer chains. In comparison of the rendered MC films from the two crosslinking methods, some important characterizations such as moisture adsorption, thermal properties, gel content, degree of swelling, and composting degradation were determined. MCs prepared from both crosslinking techniques show negligible effects on thermal properties such as T[subscript g] and T[subscript d]. In the swelling behavior, the radiation crosslinked MC films show higher polarity than chemically crosslinked MC films. From the visual observation of water-swelled crosslinked MC films, the radiation crosslinked MC films were observed to render heterogeneous gel structure whereas the chemically crosslinked MC films were found to provide homogeneous gel structure. The chemically crosslinked films at 0.3% and 0.5% by weight of a GA crosslinker can prolong the biodegradation time of the MC specimens.