Symmetric star architectures

The term star-block copolymer is used for a star architecture in which each arm is a diblock. The influence of chain topology on mechanical and morphological properties was investigated for copolymers composed of PS and PB with a constant styrene content of = 0.74 by Michler s group (Fig. 32) [101,102], While hexagonally packed cylinders of PB in a PS matrix were observed in a symmetric PS-fo-PB-fr-PS triblock copolymer, an L phase... 

Asymmetric star polymers are megamolecules [1] emanating from a central core. In contrast to the symmetric stars very little was known, until recently, about the properties of the asymmetric stars. This was due to the difficulties associated with the synthesis of well-defined architectures of this class of polymeric materials. The synthesis, solution and bulk properties, experimental and theoretical, of the following categories of asymmetric stars will be considered in this review ... 

The influence of the architecture on the phase behaviour of symmetric miktoarm stars AnBn (Fig. 34c) was investigated by Grayer et al. [119]. Symmetric miktoarm-star copolymers PS-arm-P2VP having a mean func-... 

The success of the slip link model for symmetric and asymmetric star polymers inspires its application to more complex architectures, such as H polymers. The mechanisms of relaxation and branch point motion were established in studies of symmetric and asymmetric star polymers, as were the parameters (Mf,, and Tg) that allow the simulations to be compared... 

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