DSC studies are given for polytetrahydrofurans with molecular masses equal to 650, 1400, and 2900, for their blends, and for
their cured samples. The samples were stored, annealed, and quenched to obtain the samples with different thermal histories.
Two or more endothermic peaks appear in the DSC curves for the stored samples, even for the non-blended samples. A hyperbolic
curve forced the plot of the highest melting temperature vs. the molecular mass to asymptote to about 50C. The relationship
between the highest melting temperature and the composition for the blended samples is suitable to linear or Fox’s relation.
A peak and a shoulder appear in the DSC curves of the cured samples. As the samples are cooled at the faster rates in the
thermal treatment, the shoulder appears at the lower temperatures.