Correlation of differential thermal analysis data with the shrinkage temperature of collagen and leather

Shrinkage temperature data obtained on suspended specimens of raw hide substance and a variety of commercial leathers are compared with values obtained by measuring the thermodynamic changes using differential thermal analysis. In every instance the correlation between the data of these two methods was statistically highly significant, and it is concluded that they measure the same basic phenomenon. It is suggested that the absolute values for the phase transition measured by DTA be used as the reference for the thermal behavior of collagen and its products. Use of suspended specimens offers a simplified procedure, which could be defined as a method for the measurement of shrinkage temperatures. The use of pressurized equipment permitted the extension of the temperature range to include products shrinkage above the boiling point of water (100°C).