Hybrid dendritic-linear macromolecule

Figure 7.1 Types of hybrid dendritic-linear macromolecules...

This chapter will not attempt to present encyclopedic coverage of the field, but it will only provide representative examples of the processes used to access each of the main types of hybrid block architectures, then it will take a somewhat closer look at specific families of amphiphilic or electroactive hybrid dendritic-linear macromolecules with broad potential for practical applications. 

It is also possible to introduce polymerizable groups at the focal point of dendritic macromolecules and a number of authors have demonstrated the synthesis of novel hybrid dendritic-linear block copolymers by this methodology [69-73]. Initial experiments in the use of the dendritic macromonomers involved the preparation of a series of polyether dendrimers, such as the third generation derivative, 37, which contains a single styrene at its focal point [74]. Copolymerization of 37 with styrene then affords a hybrid block copolymer, 38, in which... 

T., Hult, A., and Malkoch, M. (2013) Multifunctional Poly(ethylene glycol) synthesis, characterization, and potential applications of dendritic-linear-dendritic block copolymer hybrids. Macromolecules, 46 (10), 3726-3736. 

It is clear that the combination of different architectures and the precise localization of functionalities within a single macromolecule provide unique opportunities for the control of molecular shape as well as molecular, optical, and electronic properties. A significant hurdle that still remains today is the relatively demanding multistep process used to prepare dendrons and hybrids. This, in turn, translates into limited availability but, as high added-value applications emerge, it is clear that current, as well as yet-to-be-developed, syntheses will be used to prepare specialty materials that benefit from the unique properties derived from the combination of dendritic and linear architectures. 

Gitsov 1, Frechet JMJ. Solution and solid-state properties of hybrid linear-dendritic block copolymers. Macromolecules 1993 26 6536-6546. 

Gitsov 1. Hybrid linear dendritic macromolecules from synthesis to applications. J Polym... 

Figure 28 Synthesis of 7-oxanorbornene macromonomer derived from two (G = 1)dendronsfoiiowedby ROMP polymerization into a linear dendritic hybrid architecture. (Courtesy of Macromolecules, 39(19) 5786, 1997. Copyright 1997 American Chemical Society.)...

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