Block copolymers nonlinear

Rheometers are currently under development that will enable the anisotropic stress tensor of anisotropic complex fluids such as block copolymer melts and solutions to be probed, even during large amplitude shear. Here, a small amplitude probe waveform is applied orthogonal to the primary large amplitude shear flow. This could provide the linear dynamic modulus of an anisotropic system under nonlinear flow. 

The synthesis and bulk and solution properties of block copolymers having nonlinear architectures are reviewed. These materials include star-block copolymers, graft copolymers, mik-toarm star copolymers, and complex architectures such as umbrella polymers and certain dendritic macromolecules. Emphasis is placed on the synthesis of well-defined, well-characterized materials. Such polymers serve as model materials for understanding the effects of architecture on block copolymer self-assembly, in bulk and in solution. 

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