Enhanced flexibility and thermal characteristics of poly(lactic acid) based biocomposites with poly(ethylene glycol) and montmorillonite clay by solvent casting method

Abstract

Poly(lactic acid) is one of the most widely used bioplastics. PLA is derived from lactic acid monomer which is produced by fermentation using microorganisms. It is renewable, biodegradable, biocompatible, and lowcost aliphatic thermoplastic bioplastic. However, it displays low barrier properties to use packaging applications compared with conventional polymers. PLA has brittle, low toughness, and low thermal resistance properties. To improve the weak properties of PLA, copolymers of lactic acid are synthesized or blends of PLA with other synthetic and biodegradable polymers are prepared. PLA has been used as mulching films, biomedical devices, packaging, and membrane materials. In this study, PLA films were prepared by solution casting method using a high shear mixer for 90 sec. PLA films were blended with different concentrations of poly(ethylene glycol) (PEG) and Montmorillonite (MMT). Properties of mechanical, thermal, and optic of biodegradable films were determined using mechanical testing machine Zwick Z 1.0 kN, thermogravimetric analysis, differential scanning calorimetry (DSC), and optical microscopy, respectively.