Biodegradation of silver functionalised cellulose fibres

The efficiency of different chemical forms of silver in protecting cellulose fibres against biodegradation was studied using a soil burial test. Cotton samples were finished using nanopowder of elemental silver with a particle size of 30 nm (Ag-1), dispersion of AgCl (Ag-2), and colloidal silver (Ag-3) of different concentrations. The degree of biodegradation was determined by SEM, colour measurements, tensile strength, degree of polymerization and FT-IR spectroscopy. The results showed that a strong agglomeration of Ag-1 led to its insufficient antimicrobial activity, since it was restricted only to Ag+ released from the surface of elemental silver by reduction. Despite the agglomeration, a concentration of Ag+ released by the dissociation of AgCl of the finish Ag-2 in the presence of moisture was high enough to provide excellent protection against fibre biodegradation. The high protective properties of Ag-3 were probably caused by the synergistic action of Ag nanoparticles and Ag+ cations. (c) 2009 Elsevier Ltd. All rights reserved.