Characterization of Neat Elastomeric Polypropylene

In this section, we present the morphology development of neat elastomeric polypropylene as well as its blend with POE by means of optical microscopy and atomic force microscopy. ePP is essentially atactic polypropylene, which is amorphous in character, but contains some level of isotacticity (26). The incorporation of crystal-lizable iPP blocks provides the physical junctions to these amorphous ePP to possess elastomeric properties like a network in the solid state, but these crystal junctions can be removed upon melting, and thus affords melt processability like thermoplastics. 

2 Melting Transitions and Morphology Phase Diagrams of ePP/POE Blends 

The investigations of neat ePP under isothermal crystallization by means of OM and AFM revealed that ePP shows two types of crystalline morphologies, that is, splayed 

As shown in the top left of Fig. 7.22, the melting temperature versus composition phase diagram of the blends of ePP/POE shows virtually no depression of melting transition in both ePP and POE crystals. Moreover, the lack of identifiable hquid-liquid phase separation implies that POE acts like a theta solvent to ePP crystals. 

More importantly in these AFM images, for example, the 70/30 ePP/POE blend crystalhzed at 130 and 110°C, the interrupted edges (lameUar-like texture) might be 

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