Crosslinked cellulose developed by CuAAC, a route to new materials

Abstract

This work deals with a novel and simple approach of cellulose reticulation using the Huisgen 1,3-dipolar cycloaddition, also known as a 'click chemistry' reaction, catalysed by copper and developed by Sharpless. This reaction is carried out by the addition of a true alkyne and an azide to form a triazole ring connecting the two polysaccharide chains. The addition of two different functions will allow us to control the crosslinking reaction, to avoid intra-chain reactions and thus to promote the creation of an enhanced three-dimensional network. Azidodeoxycellulose was obtained with a DS of 1.5 from tosyl cellulose. The propargylation reaction in aqueous media leading to propargylcellulose with a DS of 1.3. CuAAC reaction was performed between azidodeoxycellulose and propargylcellulose in a DMSO/H(2)O system using CuSO(4), 5H(2)O/sodium ascorbate as catalytic system. The modified cellulose products were analysed by infrared, NMR and X-ray photoelectron spectroscopies and resulting material was analysed using scanning electron microscopy (SEM).