Phenyl carbamates of celluloses from different sources, including bacterial cellu­lose, have been prepared in BMIMCl as solvent by homogeneous conversion with the corresponding isocyanate [14, 15]. No byproducts are formed during this reaction and the DS could be tuned over the whole range, up to a maximum of 3.0, by adjusting reaction time and the amount of derivatization reagent. ‘Carbanilation’ proceeds with only minor chain degradation and yields organosoluble derivatives. Consequently it is an important tool for determination of the molecular weight of cellulose by size exclusion chromatography [74]. More­over, cellulose carbamates can be utilized as chiral stationary phase for the chro­matographic separation of enantiomers [59].

ILs have been exploited successfully for the homogeneous preparation of several cellulose-gra/f-copolymers. Grafting of poly-L-lactide and poly(e-caprolactone) chains onto the cellulose backbone has been achieved by ring opening polymeri­zation with DMAP or stannous octanoate as catalyst [43—45, 47]. Depending on the amount of monomer used, different DS values in the range of 0.1-2.7 could be achieved; the average number of repeating units was rather low («1-5). Thermo­plastic mixed derivatives containing acetyl moieties and grafted poly (L-lactide) chains have been obtained as well in a combined ‘one-pot’ reaction [46]. Cellulose — graff-poly(acrylamide) and — poly(accrylate) have also been prepared in ILs, by radical polymerization, induced by y-ray irradiation or persulfate initiation [48, 49]. In the latter case, the reaction was performed under microwave heating and a certain amount of bivalent cross linker was present, i. e., a heterogeneous polymer gel was obtained. Also the grafting of copolymers onto cellulose via ATRP has

been studied in ILs but no advantages over common molecular solvents in terms of the conversion rate could be observed [26]. Thus, it is important to decide if ILs can be beneficial in this process. At DS values >0.6, the macro initiators required in the first step dissolves, e. g., in DMF, dioxane, or butanone, i. e., ILs or other cellulose solvents are not required [23]. However, if low grafting densities are desired, ILs might prove to be useful as reaction media for homogeneous grafting of polymers onto cellulose via ATRP.