Effect of Glycerol as plasticizing agent on the mechanical properties of Polyvinyl Alcohol/Banana peel powder blended film

Nowadays, plastic pollution becomes more serious due to the abundance of petroleum-based plastic bags. Hence, economical viable biodegradable plastic is seen as a viable solution. Polyvinyl alcohol (PVA) can blend with banana peel powder (BPP) to form biodegradable film that can be degraded easily. Different compositions of glycerol (0–2.0 ml) were added to the blend to investigate the mechanical properties of the PVA/BPP blended films. PVA/BPP blended films prepared using the solution casting method were analyzed using attenuated total reflectance spectroscopy (ATR), thermogravimetric analysis (TGA), and biodegradability test. Besides, the mechanical properties of PVA/BPP blended films were analyzed using the tensile test to determine their tensile strength, elongation at break, and elastic modulus. The increment in the glycerol composition was found to decrease both tensile strength and elastic modulus of the blended films. However, the elongation at break increases as the composition of glycerol increases. The tensile strength and elastic modulus of PVA/BPP blended film without glycerol (6.65 MPa, 81.9 MPa) are higher than the PVA/BPP blended films with glycerol (4.318 MPa to 3.616 MPa, 49.99 MPa to 30.14 MPa). Moreover, the elongation at break of the PVA/BPP blended films that contain glycerol (34.27% to 48.31%) is higher than the blended film without glycerol (32.72%). After two weeks of biodegradability test, the PVA/BPP blended films that contain 2 ml of added glycerol have the highest biodegradability (11.55%) among all PVA/BPP blended films. As compared to the tested commercial plastic bag film, the BPP/PVA blended films show better biodegradable performance.