Enhanced thermal and mechanical properties of

Enhanced thermal and mechanical properties of
chitosan membrane by silver nanoparticles
Chih-Wei Chou1, Yung-Hsiu Chen1, Ko-Shao Chen2
1Department of Cosmeceutic, China Medical University, Taiwan,
2Department of Materials Engineering, Tatung University, Taiwan
In this study, we have prepared the nanocomposites of chitosan incorporated
with two type silver (Ag) nanoparticles (Ag 1, 25 nm and Ag 2, 45 nm). The
nanoparticle size, dispersion, thermal stability, mechanical properties, surface
morphology, and free radical scavenging ability of nanocomposites were
characterized in vitro. The Ag 1 and Ag 2 exhibited a homogeneous dispersion in
chitosan matrix. A significant increase in the thermostability and mechanical
properties of the polymer was demonstrated in the nanocomposite chitosan films,
which was believed a result of induced crystallization in the presence of Ag
nanoparticles. The better free radical scavenging effect was associated with the
surface morphological change in the presence of Ag. The nanocomposite containing
30 ppm of Ag 1 or 60 ppm of Ag 2 was found to possess optimal free radical
scavenging ability, and much increased biocompatibility in vitro.