Linear PS--PCL versus Miktoarm PS2 -- PCL2 Block Copolymers

1 Linear PS-fr-PCL versus Miktoarm (PS2)-6-(PCL2) Block Copolymers 

The (PS)2-fe-(PCL)2 miktoarm star copolymers were synthesized in two steps, using high-vacuum techniques and a heterofunctional initiator derived from pentaerythritol with two free and two protected -OH groups. The linear PS- -PCL block 

The molecular characteristics of the materials evaluated in this paper are provided in Table 11.5. In the notation here employed, the subscript numbers denote the mass fraction in weight percent and the superscripts give the number-averaged molecular weight M in Kg/mol of the entire copolymer. 

Both linear and miktoarm star copolymers were found to undergo microphase segregation (see details in Refs [65,92]). 

The (PS)2-( -(PCL)2 miktoarm star copolymers were found to display more compact morphologies for equivalent compositions than linear PS-ft-PCL diblock copolymers. As a consequence, the crystallization of the PCL component always experiences much higher confinement in the miktoarm stars case than in the linear diblock copolymer case [65]. 

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