![]() Presently, there are collectively over 27 000 scientific reports and 37 000 patents or patent applications dealing with dendritic structures. ![]() The first full-embodied successful synthesis of regularly branched polymers with monodisperse configurations, later denoted as dendrimers, was reported by Tomalia and coworkers 10 at Dow in the early 1980s in parallel with Newkome's ‘arborol’ systems. 8 that describes these architectures and later the first successful synthesis of lower generation dendron-like architectures by Vögtle et al., 9 the research on these architectures has been expanding with unprecedented pace. 6,7 Since the first theoretical report by Flory et al. In contrast to linear polymers with random coil conformation, highly branched dendritic polymers are condensed frameworks that lack entanglements and therefore display intriguing solution viscosity behaviour with increasing molecular weights. The field of dendritic materials encompasses various subclasses, defined by their structure, such as monodisperse dendrimers and dendrons, as well as polydisperse hyperbranched polymers, dendrigraft polymers, dendronized polymers and linear–dendritic block copolymers ( Figure 1.1). These structures belong to the newest addition in the field of polymers and are a result of taking advanced organic chemistry to a macromolecular level. 4,5 A direct response to the increased demand for sophisticated macromolecules is found in highly branched dendritic polymers – a subcategory within polymer architectures. (i) sequence-controlled insertion of the monomers within the main chain, 1–3 (ii) introduction of functional groups in a controlled matter and (iii) polymers that react to external stimuli with great efficiency. In polymer chemistry, precision polymers with well-defined structural control are now proposed with greater pace, e.g. ![]() Consequently, the progression and advances in structural diversity of polymeric architecture are important steps towards future high-performance materials. Independent of area of use, the inherent structure of a polymer has a substantial impact on the material properties in which the polymer is imbedded. This is strongly evident in all scientific communities including the field of polymer science in which the synthetic machineries of polymers have been altered. It is evident that today's high demand for cutting-edge materials is evermore increasing at a rapid pace. More in-depth synthetic description and their related references for structurally specific architectures can be found in the later chapters in this book. A rationale on how to synthetically approach dendrimers is provided, from choice of monomers, growth route and pitfalls that accompany their construction. Consequently, a large part of this chapter describes previous and recent synthetic approaches to dendrimers that have successfully been accomplished, such as traditional and accelerated growth strategies, as well as their pros and cons. As monodisperse dendrimers are the pinnacle of dendritic polymers that are synthesized via a cascade of successful reactions steps, it is pivotal that chemists utilize reactions known for their robustness and simple purification. From a researcher point of view, a major drawback to exploiting this class of polymers is strongly related to their accessibility, especially synthetically challenging and flawless dendritic scaffolds. Its content will give the reader interested in venturing into the field of dendritic polymers, the general synthetic options with respect to choice of scaffolds. ![]() These include monodisperse dendrons and dendrimers as well as polydisperse hyperbranched polymers, linear–dendritic copolymer hybrids, dendronized polymers and dendrigrafts. This chapter will provide a descriptive overview of the different classes that define dendritic polymers and their subcategories.
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