Measurement of Fiber Saturation Point of Wood Using Differential Scanning Calorimetry: Measurement Fundamentals and Experimental Results

In this research, the measurement fundamentals of fiber saturation point (FSP) using differential scanning calorimetry (DSC) method were explained. This method is based on the assumption that free water is frozen but bound water remains unfrozen in low temperatures. Thus, the FSP can be calculated by measuring the enthalpy of melting of frozen wet samples. This method measures the amount of energy absorbed or released by a sample when it is heated or cooled. Results showed that the DSC method may yield a higher FSP value compared to the widely accepted value of 30%, depending on the wood species. Both thermal and chemical (acetylation) modification methods reduced the FSP but in the acetylation method, there was no linear correlation between the weight gain percentage (WPG) and FSP.