Thermal and Morphological Properties of Chitosan Filled Epoxy

This paper investigates the effects of polysaccharide additive agent on the morphological and thermal properties of thermosetting polymer. The weight percentage (wt%) of Diglycidyl Ether of Bisphenol A (DGEBA) epoxy resin to Hexamethylenediamine (HMDA) hardener were kept constant while a varying wt% of chitosan, ranging from 0 to 10 wt% was introduced. The chitosan filled epoxy hardener mixture was allowed to cure at 40°C for a period of 12 hours. Dynamic Scanning Calorimetry (DSC) and Thermal Gravimetric Analysis (TGA) were conducted on the specimens to analyse the effects of chitosan loading on thermal stability and transition temperature while Atomic Force Microscopy (AFM) was used to investigate the changes to its morphological property. At chitosan loading of 2.5 wt% and below, good dispersion of the additive was observed. Apparent agglomeration and phase separation were formed when chitosan content increases above 7.5 wt%. The formation of bulky chitosan agglomeration was found capable of enhancing the thermal stability of the thermoset polymer. The diamine acted as the co-reactants with DGEBA as well as spacer which decrease the effect of material brittleness due to addition of chitosan.