Staudinger, macromolecules

Figure 4. Professor Herman Mark and models of flexible (Mark) and rigid (Staudinger) macromolecules. The photograph was taken in Brooklyn on October...

Priesner, C. (1980). H, Staudinger, H, Mark und K, H, Meyer - Thesen zur Grofie und Struktur der Makromolekiile [H, Staudinger, H, Mark and K, H, Meyer — Theories about the Size and Structure of Macromolecules], Weinheim Verlag Chemie. 

Staudinger relentlessly championed the molecular, or primary valence, viewpoint in the years which followed. He supported his original contentions with the observation that hydrogenation of rubber, as well as its conversion to other derivatives, does not destroy its colloidal properties. In contrast to association colloids, high polymers (or macromolecules as he chose to call them ) exhibit colloidal properties in all solvents in which they dissolve. Polyoxymethylenes were ex-... 

To answer Staudinger s critics, Carothers knew he had to resolve three issues. First, he would have to build one of Staudinger s macromolecules. Next, he would have to confirm that they were indeed long-chained molecules, not merely aggregates of smaller molecules, as others claimed. Finally, he would have to prove that the forces holding the chains together were ordinary valence bonds, rather than a mysterious weak force. 

Carothers had already settled the controversy between Staudinger and his opponents. He had built Staudinger s macromolecules, and the properties of his macromolecules were identical to those of natural polymers. Even more, his path breaking technique of condensation polymerization had demonstrated that his macromolecules consisted of long chains held together by ordinary valence bonds. 

German scientist Staudinger in 1920 stated that colloidal properties of organic materials are because of the large size of individual molecules. He also stated that macromolecules contain only primary covalent bonds. 

Hermann Staudinger received the Nobel Prize in Chemistry in 1953 for his work on macromolecules. The award not only acknowledged the contributions of the man who first proposed use of the name "macromolecules" (57), but recognized the field of macromolecular chemistry. In his address to Staudinger for the award of the Nobel Prize, A. Fredga said ... 

A glimpse of the stormy events of 1925 to 1930 was seen on the occasion of Staudinger s farewell address to the Zurich Chemical Society. Staudinger lectured at the meeting on the existence of thread-like macromolecules consisting of a long series of "Kekule" or covalent bonds. Since his model was in... 

Staudinger was probably the first to recognize this, for in 1928 he proposed that synthetic macromolecules were poly-disperse and their molecular weights would have to be expressed as average values (93). He also recognized the dependence of physical properties on molecular weight, and pursued this dependence as a measure of molecular weight determination. The result was his application of solution viscosity. 

Fredga, A. "Les Prix Nobel en 1953" Stockholm, 1954 p. 27 (cited in Staudinger, H. "From Organic Chemistry to Macromolecules Wiley-Interscience New York, 1970 p. 7.). ... 

In 1926 Staudinger was totally involved in defending his ideas regarding the macromolecule. On the other hand, Mark, at the Fiber Research Institute in Dahlem, was riding the crest of acclaim as an outstanding crystallographer and expert in molecular structure. The two were requested to present papers by R. Willstaetter at a special symposium of the "Gesellschaft Deutscher Naturforscher und Arzte". 

Their model is a compromise between the association theory and Staudinger s macromolecules. 

I do not believe that the introduction of primary valence chains, instead of macromolecules, solves any problem." Staudinger also stated these views publicly (29). 

Mark responded to Staudinger on November 2, 1928. Among other things he wrote, "I am sorry to see from your letter that you feel annoyed by the statements of Professor Meyer. I am convinced that it was the last thing Professor Meyer intended to do. I have, in our joint research and especially in my Hamburg lecture, emphasized the importance of your beautiful work. Introduction of the term, primary valence chain, is very purposeful since it refers to structures which are not identical. . . rather average lengths. If we add this fact to your macromolecules, then both concepts become identical. 

In deriving his equation, Staudinger assumed the macromolecules were straight, rigid rods. This assumption is, with hindsight, wrong. Its accuracy because of inaccuracies is ironically good. 

The acceptance of macromolecules was still hotly debated even though the work of Hermann Staudinger in the 1910 s and the 1920 s showed, at least to some, that macromolecules did indeed exist. 

Staudinger, H. From Organic Chemistry to Macromolecules, A Scientific Autobiography, John Wiley Sons, New York, (1961). 

Carothers and his research group synthesised many polyesters, nearly all of them aliphatic. His basic patent was filed on July 3, 1931 [23], This work, together with his work on condensation polymers in general, proved influential in convincing the scientific community that polymers were indeed macromolecules, as maintained by Staudinger, and not assemblies of small molecules in a special state of association. Staudinger himself was initially reluctant to accept that the polyesters were polymers, since he had defined polymers in such a way as to refer solely to products of addition reactions. He thus excluded products of condensation reactions, where small molecules were eliminated as co-products of the reaction [24],... 

This recognition of proteins as macromolecules was staunchly advocated by Staudinger (1920 et seq.) in spite of vociferous opposition Organic molecules with more than forty C atoms do not exist. Purify your products. . . they will prove to be lower molecular weight substances. Even as late as 1938, Gorter maintained All of the reactions and interactions which we call life take place in colloidal systems. ... 

By 1953 the complete primary sequence of insulin was known. Sanger could thus conclude that proteins like insulin had unique structures and were, as Staudinger had postulated, defined macromolecules. The primary sequence of other proteins soon followed. 

The viscosity of the solution is significantly increased when macromolecules are dissolved in a solvent. The specific viscosity of a solution t sp=(ri-r o)lr o expected to increase proportionally to the concentration c. The reduced viscosity rjgp/c still increases with increasing concentration. The data, however, can be extrapolated to zero concentration and results in the intrinsic viscosity, or the viscosity number [77], sometimes also called the Staudinger index... 

Staudinger realized that for macromolecules [77] depends characteristically on the molar mass which can be expressed by the Kuhn-Mark-Houwink-Sakurada (KMHS) relationship... 

Hermann Staudinger studied the polymerization of isoprene as early as 1910. Intrigued by the difference between this synthetic material and NR, he began to focus more of his studies on such materials. His turn towards these questionable materials, of interest to industry but surely not academically important, was viewed unkindly by his fellow academics. He was told by one of his fellow scientists Dear Colleague, leave the concept of large molecules well alone There can be no such thing as a macromolecule. ... 

A macromolecule is defined according to Staudinger 4) as a molecule of more than 1000 atoms... 

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