Heterogeneous chemical modification of cellulose for composite materials

Two different cellulosic substrates in the form of powders and regenerated fibers were surface modified with different isocyanates in a heterogeneous organic medium. Two of these isocyanates also bore alkenyl functions which were used as a means of copolymerization in subsequent reactions involving common monomers. The third isocyanate bore instead a non reactive C18 linear aliphatic chain. The fibers modified by either the latter single reaction or the former double procedure were introduced into macromolecular matrices in order to elaborate composite materials and study their properties. All the envisaged reactions were shown to occur and the application of the fragmentation test to the corresponding composite materials provided quantitative evidence of the improvement of fiber-matrix adhesion associated with the different modifications.