Cellulose fibers have been successfully grafted with poly(methyl acrylate) using atom transfer radical polymerization, mediated by Me6-TREN and Cu(I)Br at ambient temperature. The initially hydrophilic cellulose was first modified by reacting the hydrozyl groups with 2-bromoisobutyryl bromide whereupon methyl acrylate was grafted from the surface. The resulting polymer-grafted papers were extremely hydrophobic, thetaa = 133 degrees . FT-IR analysis indicates that the amount of grafted polymer can be controlled by adding sacrificial initiator to the polymerizing system. Size exclusion chromatography of the bulk polymer revealed narrow polydispersities and a molecular weight corresponding to the ratio [M]:[I].

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In this study, ring-opening polymerization (ROP) of epsilon-caprolactone (epsilon-CL) and L-lactide (L-LA) has been performed from cellulose fibers. The hydroxyl groups on cellulose act as initiators in the polymerization, and the polymers are covalently bonded to the cellulose fiber. As an attempt to introduce more available hydroxyl groups on the surface, and thereby obtain higher grafting efficiency in the ROP of epsilon-CL and L-LA, unmodified paper was modified with xyloglucan-bis(methylol)-2-methylpropanamide (XG-bis-MPA) and 2,2-bis(methylol)propionic acid (bis-MPA), respectively. The grafted substrates were characterized via Fourier transform infrared spectroscopy (FTIR), contact angle measurement, atomic force microscopy, and enzymatic degradation. The results showed a successful grafting of poly(epsilon-caprolactone) (PCL) and poly(L-lactic acid) (PLLA) from the cellulose fiber surfaces. Furthermore, the results showed an improved grafting efficiency after activation of the cellulose surface with bis-MPA, and showed that the amount of grafted polymer could be controlled by the ratio of added free initiator to monomer.