Corona discharge treatment route for the grafting of modified β-cyclodextrin molecules onto cellulose

Corona discharge treatment (CDT) was implemented to attempt to graft a modified β-cyclodextrin (β-CD) onto cellulose. The occurrence of grafting was indirectly proven by gravimetric analyses, X-ray Photoelectron Spectroscopy (XPS) and Scanning Electron Microscopy (SEM). Besides, the effect of CDT onto cellulosic substrate was studied using SEM and XPS. It appeared that surface roughness increased with the treatment time as a consequence of an etching effect and that surface oxidation took place as evidenced by the creation of hydroxyl and carboxyl groups. These functional groups are not responsible for chemical link between modified β-CD and substrate. It was assumed that the grafting results from the reaction of double-bonds of modified β-CD and radicals formed on treated surface, these ones being evidenced by DPPH radical trapping. Moreover the inclusion of a guest molecule is still possible in grafted modified β-CD giving a new proof of grafting.