A Study on the First Order Phase Transitions in Hydrocarbon Crystals

A polarization hot stage microscopy study was made on the phase transitions in n-octacosane and n-hexatriacontane hydrocarbon crystals. Advancement rates of transition fronts of high temperature phase in low temperature phase were measured. Transition in the interior layers was detected. In order to explain the observations, we propose a model, which involves intrachain defects in the extended chain configuration. This model is an advanced stage of the model proposed by STROBL, basing on the SAXS results.