INTRINSIC THERMAL-CONDUCTIVITY OF GELATIN ESTIMATED INDEPENDENTLY OF HEAT-CONDUCTION MODELS

The effective thermal conductivity of a two-phase mixture of solid gelatin and an aqueous 2-propanol solution was measured by the steady heat flow method with varying 2-propanol concentration. From this result, the intrinsic thermal conductivity of gelatin (lambda-p) was estimated to be 0.28-0.30 W/mK at 20-degrees-C by interpolating to a point where the effective thermal conductivity was equal to the thermal conductivity of the 2-propanol solution used as the liquid phase. The value of lambda-p was independent of temperature between 20-degrees-C and 50-degrees-C when water was not contained in the liquid phase, although it depended slightly on temperature in the presence of water. Using the estimated value of lambda-p at 20-degrees-C, the effective thermal conductivity of the gelatin gel was best described by the series heat conduction model.