A Benign Route for the Production of Polymer Nanocomposite Films Based on Poly(vinyl alcohol) and SiO2–Folic Acid Nanoparticles

The synthesis of polymer/inorganic nanocomposites (NCs) has attracted much attention. Thiscomes from the combination of the advantageous properties of inorganic nanoparticles (NPs)and polymers. SiO2 NPs are used widely due to their properties such as high refractive index,high thermal stability, non-toxicity, environmental compatibility, and relatively inexpensiveprices [1]. To solve the problem of agglomeration of SiO2 NPs, surface modification is thebest method [1]. Poly(vinyl alcohol) (PVA) is a water-soluble polymer which has been studiedas a host matrix for a large number of nano-fillers, due to its excellent properties. It is biodegradable,biocompatible and nontoxic [2]. In this paper, to prevent the agglomeration ofSiO2 NPs, their surface was modified by folic acid (FA). Then, modified NPs was placed in aPVA matrix and SiO2-FA/PVA NC films with 2, 5, and 8 wt% were produced by castingmethod under ultrasonic radiation as a green and low-cost method (Fig. 1A). Transmissionelectron microscopy (TEM) showed that the size of SiO2-FA NPs in the PVA matrix was between12-18 nm (Fig. 1B). With the insertion of SiO2-FA in PVA matrix, the thermal resistance,flexibility, and wettability properties were increased.