Semicrystalline polymer-containing

Perfectly crystalline polymers are, however, rarely seen in practice and real polymers may instead contain varying proportions of ordered and disordered regions in the sample. These semicrystalline polymers usually exhibit both Tg and T i (not r, ) corresponding to the disordered and ordered regions, respectively, and follow curves similar to E-H-D-A. Tm is lower than and more often represents a melting range, because the semicrystalline polymer contains crystallites of various sizes with many defects which act to depress the melting temperature. 

The solubility S of a semicrystalline polymer containing a crystalline volume fraction of a. and with an amorphous phase solubility is given by ... 

Polymers can exhibit a hierarchical organization of structure at four successive levels, the molecular, nano-, micro-, and macrolevel [33, 34], On the scale of tens of microns, semicrystalline polymers contain spherulites, the spherulites have a lamellar texture, and the molecules within the lamellae are organized in crystals and amorphous domains. Amorphous polymers are structured on the molecular and macroscopic scale only [34]. Thermoplastic SMPs are usually phase-segregated materials, i.e., they consist of at least two different domains, which are related to different thermal transition temperatures (Tinms)- Therein hard domains have a TJrans (glass transition temperature Tg or melting temperature 7]n) usually much higher than room temperature and determine the permanent shape, while switching domains show a lower thermal transition (Tg or 7]n). SMP networks contain chemical crosslinks instead of hard domains to fix the permanent shape. 

Semicrystalline polymers contain liquid-like amorphous and ordered crystalline phases. When solidified from the pure melt, these polymers show a spherulitic structure in which crystalline lamellae composed of folded chain crystallites radiate from the center of the spherulite in such a way that a constant long period or crystallinity is apvproximately maintained. The amorphous regions reside in the interlamellar regions in the form of tie chains, whose ends are attached to adjacent lamellae loop chains, whose ends are attached to the same lamella cilia chains with only one end attached to a lamella (or dangling chain ends), and floating chains which are not attached to any lamellae. This hierarchical structure is illustrated in Figure 1. 

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