Staudinger’s macromolecular concept

From purely empirical optimisation of materials to molecular material design — this, in a nutshell, is the most tangible progress that has been made thanks to Staudinger s macromolecular concept and that is highlighted when tribute is paid to Staudinger s historical achievements. His concept [...] that was revolutionary at the time paved the way for the molecular design of functional and decorative polymer materials, the property profiles of which are customised for specific applications via the molecular architectures [24, p. 1072]. 

Crystallinity in polymers was first observed by X-Ray Diffraction even before these materials were understood to be polymers. Prominent examples were polysaccharides, especially cellulose (Herzog et al. 1920) and stretched natural rubber (Katz 1925). This was before Staudinger s macromolecular concept was widely accepted (Morawetz 1995). By the time synthetic crystalline polymers such as polyethylene (in 1933) and nylons (in 1935) were developed, it was generally acknowledged that the unit cell of a polymer crystal was based on repeating monomer units, rather than on the whole molecules. 

Staudinger s historical merits for our knowledge of diazoalkanes, based on his work between 1911 and 1921, became somewhat overshadowed by his later and clearly more fundamental and pioneering ideas about the formation and structure of macromolecules (Nobel Prize 1953). It should be emphasized, however, that his development of the concept of polymerization was, at least in part, based on his observations of the formation of polymethylene in the dediazoniation of diazomethane. Macromolecular chemistry, therefore, appears to be a child of early diazo chemistry ... 

Other investigators in the nineteenth century including Emil Fischer, reported unusually high molecular weights for natural polymers. Nevertheless, confusion between concepts of colloids, the association theory and that of macromolecules continued to retard progress until Nobel Laureate Hermann Staudinger championed the true macromolecular concept in the early 1920 s. 

By the end of the 1920 s Staudinger s efforts to prove the macromolecular concept by chemical reactions with polymers and by improved x-ray stodies on < llulose, silk rubber and chitin, by systematic measurements with the ultracentrihige and, perhaps most of all by the brilliant synthetic work of W.H. Carothers in the laboratories of the DuPont company, he succeeded in preparing polyesters and polyamides in the macromolecular range and determined their molecular weight by exact and reprodudble end group analysis. 

Staudinger s self-confident predictions proved to be correct the macromolecular concept stimulated material research and really did lead to an industrial boom soon afterwards ... 

Macromolecules that contain two or more topologically distinct components are complex architectures that can lead to emergent properties or behaviors that are different to those of either of the individual molecular architectures. Dendronized polymers [16-19] are examples of such complex molecular architectures and are composed of a linear polymer backbone and perfectly branched dendritic side chains on each repeat unit (Scheme 1). The molar masses of such polymers emphasize the shift in thinking brought about by Staudinger s concept of macromolecules [1,2]. Individual dendronized polymers are nanoscopic objects [20-25] whose organization in bulk is determined by hierarchical processes that occur on a different set of length scales compared to conventional polymers [16,26]. By virtue of the size and shape of dendronized polymers, interest in this complex macromolecular architecture has moved toward how to extract functionality from these nanoscale molecular objects. 

---