Chemical structure and compatibility of chitosan and nylon - 6 blends

Abstract

Nowadays, polymer blending is one of the most effective ways of providing a new and desirable polymers materials. Modification of chitosan by blending with another polymer can be explored further due to its functional groups. In this study, solution blending technique is used to blend chitosan and nylon-6 which also contains suitable functional group that can promote compatibility between these polymers. Film composed of nylon-6, chitosan and its chitosan/nylon-6 blends are employed to investigate the interaction between those two polymers. FT-IR results show the displacement of carbonyl band amide group of chitosan to the smaller wavelength. It implies that there is existence of strong hydrogen bonding between these two polymers which can promote towards the compatibility of chitosan and nylon-6 blend. DSC analysis of the blend also showed a reduction of melting point (Tm) and heat of enthalpy (AHm) due to the formation of new hydrogen bonds between polymer molecules. While, SEM analysis showed that the smoothness surfaces of pure chitosan gradually disappear and the flat dense surface became undulating. Due to the immiscibility between chitosan and nylon-6, its blend also have scattered round plaque like structure. All the results shown that increasing in DD of chitosan will increase the compatibility between chitosan and nylon-6 blend.