Novos nanocompósitos de celulose bacteriana preparados por polimerização in situ
authors Ana Rita Parente Figueiredo
supervisors Armando Jorge Domingues Silvestre; Carmen Sofia da Rocha Freire Barros
thesis type Mestrado
abstract Cellulose is the most abundant polysaccharide in Nature being the main structural component in plants, and having a high economic importance, namely in paper and textile industries. Besides plants, cellulose is also produced by some bacteria, the so called bacterial cellulose (BC). BC has unique properties such as high water holding ability, mechanical strength, biodegradability and biocompatibility; that attracted its attention towards several fields. One of the BC applications is the development of nanocomposite materials, with applications ranging from biomedical field, as tissue scaffolds, to more technical fields such as packaging materials. So, the aim of this work was to prepare bacterial cellulose-poly(2-aminoethyl methacrylate) (PAEM) nanocomposites by in situ radical polymerization, using variable amounts of N,N-methylenebis(acrylamide) (MBA) as crosslinker agent. Several nanocomposite films were prepared, showing to be significantly more transparent than BC, with improved mechanical properties and thermal stability, in comparison with the pristine polymers. Furthermore, the nanocomposite materials show high swelling ability in water after drying as well as decreased crystallinity, in comparison with pure BC, as a result of the incorporation of amorphous polymer. The antibacterial activity of the nanocomposites prepared was also assessed towards bioluminescent E. coli from which only the non-crosslinked nanocomposite (BC/PAEM) showed to have antibacterial activity.
year published 2013