Crystalline melting point, molecular structure, dependence

The crystalline melting point and the glass transition temperature of a polymer, in themselves, provide a rough characterization of the polymer properties they also provide reference points for the various regimes within which the quantitative evaluation of properties must be made. How do Tjij and Tg depend on molecular structure ... 

Fluoropolymers are semicrystalline polymers most do not exhibit glass transition in the conventional sense during which all crystalline structures are converted to the amorphous. The glass transitions of fluoroplastics have been described as molecular relaxation (conformational disorder) that takes place in the amorphous phase of the polymer. These temperatures are also called second order transitions their value depends on the technique and the frequency of energy addition to the polymer sample. Table 3.61 presents these temperatures and melting points of perfluorinated and partially fluorinated fluoroplastics. 

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