Preparation and characterization of chitosan grafted poly(lactic acid) films for biomedical composites

Abstract

AbstractPolymer composites offer a great advantage in biomedical field over the traditional materials used like, metal, ceramics, or polymer alone. Polymer composites provide tailor-made facilities to design required physiological and mechanical properties in biomedical products. Poly(lactic acid) (PLA) is a popular aliphatic polyester used in various biomedical products because they have a renewable source and after resorption they enter well into the Krebs cycle of the human body. However, PLA suffers from hydrolysis and subsequent weight loss in aqueous environment. To improve the hydrolytic properties of hydrophobic PLA and to incorporate the biocompatibility from chitosan (CS) into it, in this study CS has been grafted onto PLA film. CS with 78% of degree of deacetylation and viscosity average molecular weight of about 8,31,760 Da was grafted onto hydrolyzed PLA film surface. Kjeldahl analysis confirmed the attachment of CS onto the PLA films. From thermal stability analysis, it was observed that percentage of weight retention at 600°C of the CS-g-PLA was around 15% higher than that of pure PLA. The mechanical properties of final CS-grafted-PLA composites showed more resistance to hydrolytic degradation than that of pure PLA film.