Copolymers versus Blends of PLLA and PCL

Muller et and Castillo et al have studied in detail double 

The PLLA block within PLLA-A-PE does not form sphemlites at any examined temperature, as expected for a strongly segregated system, since 

It is noteworthy that in weakly segregated diblock copolymers like PPDX-6-PCL, the rubbery PCL block has a dramatic effect depressing PPDX crystallization rate by at least one order of magnitude.  

Castillo et al demonstrated by SAXS that the crystallization of the PE block within PLLA-Z -PE and PDLA-Z)-PE is strictly confined within the preexisting lamellar microdomains in the melt regardless of whether Tc pe Tg PLDA.PLLA (soft confinement) or PE 7 g plda,plla (hard confinement). 

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