Investigation of optical, mechanical, thermal, wettability, and antibacterial activity of polyvinyl alcohol mixed with clay nanoparticles

In this research, polyvinyl alcohol (PVA) was mixed with clay nanoparticles with weight ratios of 1, 3, or 5 wt% to form PVA/clay composites using the solvent casting method for food packaging uses. Chemical bonds and function groups were identified using Fourier transform infrared spectroscopy, while mechanical parameters e.g. tensile strength (Ts), elongation (Eb), and Young modulus (Ym) of the synthesized PVA/clay film were examined. Other characteristics were studied and discussed such as water uptake (swelling and porosity), contact angle, optical qualities (transmission, brightness), barrier properties i.e. water vapor transfer rate, and antimicrobial performance. The addition of clay nanoparticles raised Ym from 1.3 MPa to 2.9 MPa, while decreasing Ts and Eb from 77 MPa and 3.8 % to 59 MPa and 3.6 %, respectively. Also, incorporating clay nanoparticles reduces water absorption, moisture level, transmission, and brightness while improving the thermal conductivity and water vapor transport rates of PVA. Furthermore, the incorporation of clay nanoparticles improves thermal, mechanical, optical, and antibacterial performance, which could be beneficial for food packaging applications.