Synthesis and characterisation of poly (lactic acid)/halloysite bionanocomposite films

Abstract

Poly (lactic acid) (PLA)/natural halloysite nanotubes (HNTs) films were prepared by solution casting method to investigate their properties for packaging applications. Tensile test results revealed that the maximum tensile elastic modulus (1.40 ± 0.05 GPa) and tensile strength (52.75 ± 1.80 MPa) were achieved at 5 w/w % of HNTs (in a range of 0–10 w/w % HNT concentrations). A nanoindentation test was performed to confirm the reinforcing effect of HNTs. Analysis of electron micrographs of the fracture surfaces suggested that the reinforcing mechanism was subjected to the interfacial interaction between HNTs and PLA. Infrared spectra revealed that the end hydroxyl groups of PLA chemically interacted with HNTs’ outer surface siloxane groups via hydrogen bonding. In addition, the contact angle test and thermogravimetric analysis were used to investigate the surface wettability and thermal stability of the PLA/HNT films, respectively.