Investigation of Tensile Strength and Thermal Properties of Chitosan/PVA Blend Prepared at Different Ratios

In this study, chitosan/polyvinyl alcohol (CS/PVA) films were prepared with different weight ratios (98:2, 96:4, 94:6, 92:8, and 90:10%) using the solution casting method to study the structural, thermal, and tensile strength properties of the composites. The Fourier transform infrared (FTIR) spectroscopy of CS/PVA samples showed some differences, such as changes in the strength, location, and intensity of the CO and CH₂ stretching bands. The differential scanning calorimetry (DSC) results showed the highest thermal elongation at 2%, reaching 289. DSC analysis shows a significant effect on the thermal stability of the composite by increasing its melting point. The thermogravimetric analysis (TGA) showed greater thermal stability in the samples. The decomposition point was shifted to higher energy, with less mass loss in the decomposition region. Approximately 40% by mass was lost at temperatures ranging from 250 to 400 °C. The CS/PVA (98/2) wt% blend showed the best thermal stability compared to the other ratios. The film showed good mechanical properties with a tensile strength of 54.94 MPa at 2%, elongation of 3.93, and Young's modulus of 1.48 at this ratio. Scanning electron microscopy (SEM) showed that the CS/PVA blend at 2% PVA was homogeneously distributed within the chitosan matrix, or the core polymer, which explains the higher tensile strength and greater flexibility.