Mechanical strength properties of Chitin/Polylactic Acid biocomposite film

Abstract

Polylactic acid (PLA) is a biodegradable polyester that can be used for many applications such as packaging, medicine and agriculture. However, several disadvantages including brittleness, poor water vapour barrier properties and high cost production limits its application. Hence, this study focuses on developing PLA by introducing commercial chitin into PLA with the purpose of obtaining chitin/PLA biocomposite film characteristics. The chitin/ PLA film was prepared at various commercial chitin contents (1, 2, 3, and 4 phr) by solution casting method to investigate the effect of commercial chitin content on its mechanical strength properties. Tensile test and Atomic Force Microscopy (AFM) analysis were carried out to study the properties of chitin/PLA composites. The results showed that the tensile strength and elongation at break of PLA decreased with the addition of chitin. The elastic modulus of the biocomposite films increased upon addition of chitin into PLA. From mechanical properties revealed that chitin and PLA blends were incompatible and supported with the results of Fourier Transform Infrared (FTIR) analysis that showed the absence of specific interaction between chitin and PLA. Likewise, AFM showed the surface morphology of PLA was changed upon addition of chitin, with increased tendency for agglomeration of chitin at high loading which indicated poor filler dispersion in the matrix.