Reexamination of the equilibrium melting temperature of natural rubber crystals

The equilibrium melting temperature (T-m(0)) of natural rubber crystals was reexamined by the Hoffman-Weeks plot and the Gibbs-Thomson plot using the lamellar thickness obtained from the same sample as the one used for the measurement of melting temperature. The sample was prepared from deproteinized latex. As a result, the T-m(0) of NR was estimated to be 61 degrees C. At the same time, the fold-surface free energy was estimated to be 0.046 Jm(-2). These values should be more reliable than the previously assumed values.