Effect of SiO nanoparticle on the physical and chemical properties of eco-friendly agar/sodium alginate nanocomposite film.

Agar/sodium alginate (AG/SA) nanocomposite films were prepared using solution casting method in presence of various concentrations of nano-SiO (2.5, 5, 7.5, and 10 wt%). The effect of nano-SiO concentration on the nanocomposite film was investigated. The result of Fourier transform infrared (FTIR) illustrated the formation of hydrogen bonding between nano-SiO and polysaccharide. As nano-SiO concentration rose from 0 to 10 wt%, the tensile strength and elongation at break all increased up to maximum, respectively. The tensile strength and elongation at break of film containing 10 wt% nano-SiO increased by 65.29% and 60.38% respectively when compared to those of film prepared without nano-SiO. The reason for enhancing in tensile strength might be related to the formation of molecular interaction. The film containing 2.5 wt% nano-SiO had maximum water contact angle and minimum water vapor permeability among those of all films prepared in this work. However, the film containing 10 wt% nano-SiO had minimum swelling degree and water solubility, further demonstrating the formation of strong interaction. The addition of nano-SiO improved the properties of film against UV light and thermal stability. Overall, the addition of nano-SiO enhanced the mechanical properties, water resistance and thermal stability of polysaccharide film.