Modified cellulose fibers as reinforcing fillers for macromolecular matrices

Various cellulose substrates were submitted to different surface OH chemical modifications in non-swelling media and then fully characterised by FTIR, XPS, contact angle measurements and elemental analysis. The alternative procedures adopted were: (i) simple grafting with monomeric or oligomeric agents which bore one or several reactive functions, either as a single terminal moiety or as numerous moieties placed along the chain; (ii) grafting with polymerisable molecules, which involved the use of reagents of small molecular size, but bearing two functions, one able of reacting with the surface cellulose OH groups and the other used as a source of subsequent covalent linkage with the matrix; (iii) the use of planar stiff molecular configurations bearing two identical reactive functions, calling upon the working hypothesis that only one function will react with a cellulose OH group, whereas the other will be left to copolymerise with the matrix; (iv) coupling with siloxanes using the same strategy as in (ii), except for the fact that this specific approach involves molecules already commonly used in glass fibres treatment; (v) grafting with organometallics such as triethyl aluminium following the same working hypothesis as in (iii) but with a second reaction involving monomeric or polymeric alcohols or amines.