INVESTIGATION ON THE THERMODYNAMICAL PROPERTIES OF SOME NATURAL SILK FIBERS WITH VARIOUS PHYSICAL METHODS

Thermodynamical properties : such as enthalpy, heat of reaction etc. causes for thermal reaction of natural silk fibres- Muga, Eri and, Pat, endemic to North East India, have been investigated by Differential Scanning Calorimetry (DSC), Differential Thermal Analysis (DTA), Differential Thermogravimetry (DTG) and Thermogravimetry (TG) methods. The experiments have been carried out in the temperature range from 298K to 693K. The thermograms of the samples have shown two thermal reaction steps on the temperature ranges 333-405K and 560-675K. The first transition peak has been revealed the dehydration of the water molecules from the semi-crystalline hosts. The second peak has confirmed the irreversible dissociation of the crystallites. The heat of reaction, activation energy, reaction order, Arrhenious frequency factor at the dehydration and the decomposition steps for the samples have been computed. Significances of these observations for suitability of such fibres in the technological applications have been discussed.