outwardly between macromolecules and micelles to make more distinctions in the
theory of high-polymer materials and, if necessary, to correct Staudinger. Meyer
and Mark insisted in particular that the significance of secondary valences should
not be underestimated:
• Meyer [28] writes: “Staudinger assumes that association to form molecular
groups or micelles has only been determined with soaps, that hold a special
position because of their salt character. We would like to draw attention to the
fact that they can be detected in all higher-molecular compounds [. . .]” (quoted
by [15], p. 96).
• Meyer [29] writes: “In contrast to Staudinger, [. . .] we observe the structure of
the [. . .] high polymers in solution, when Staudinger says [. . .] that they have no
micellar character. We, however, are convinced that cluster or micelle formation
plays a key role in the high-polymer materials in solution too” (quoted in [15],
p. 108).
• Priesner et al. [15], p. 337) comment: “Whereas to Staudinger there was a clear
distinction between primary and secondary valences and no attempt was made to
obtain information about the nature of the individual types of bond, the physical
chemistry approach demanded stronger distinction. [. . .] The strength of both
primary and secondary valences was not observed to be constant; instead of this,
it varied according to the structure of the molecules. As far as size was
concerned, a strong secondary valence could therefore very definitely correspond to a weak primary valence.”
On the basis of what we know now, Mark and Meyer were in actual fact “not
completely wrong” [11, p. 48], because it is true that macromolecules can “definitely in suitable conditions form micelles in their solutions too ([11], p. 48; cf. [18],
p. 233). “More or less highly aggregated groups of molecules are also solvated in
colloidal solutions alongside individual molecules, depending on the solvent concentration. Micelles are just as real as individual macromolecules” [15, p. 115],
although the term is nowadays reserved exclusively for “aggregates of small
molecules” [15, p. 82]. Minssen and Walgenbach [20, p. 99] go even further:
“The concept of chemical primary valence with its defined bonding relationships
does not explain all the characteristics of a substance.” Denaturation of enzymes
could, for example, be described best by saying that the primary valence bonds
were maintained, whereas the secondary valence bonds were broken. Minssen and
Walgenbach [20, pp. 60–61] go on: “In the case of what are known as biological
macromolecules, e.g. nucleic acids and ‘proteins’, particularly enzyme proteins, the
sensitivity to heat [. . .] cannot be explained any more via a molecular structure
involving primary valences. [. . .] Staudinger is wrong when he says that the reason
for the instability when exposed to heat is because the molecules ‘disintegrate’ due
to the elimination of primary valences (1926). The introduction of secondary
valences accordingly allows [. . .] the description of more complicated structures
and behavioural patterns than is the case when the theory is reduced to standard
valences.” Staudinger’s concept needed “to be abandoned as too limiting. To this
extent, his opponents are celebrating a belated triumph.”
Courageous Questioning of Established Thinking: The Life and Work of Hermann. . .
103
theory of high-polymer materials and, if necessary, to correct Staudinger. Meyer
and Mark insisted in particular that the significance of secondary valences should
not be underestimated:
• Meyer [28] writes: “Staudinger assumes that association to form molecular
groups or micelles has only been determined with soaps, that hold a special
position because of their salt character. We would like to draw attention to the
fact that they can be detected in all higher-molecular compounds [. . .]” (quoted
by [15], p. 96).
• Meyer [29] writes: “In contrast to Staudinger, [. . .] we observe the structure of
the [. . .] high polymers in solution, when Staudinger says [. . .] that they have no
micellar character. We, however, are convinced that cluster or micelle formation
plays a key role in the high-polymer materials in solution too” (quoted in [15],
p. 108).
• Priesner et al. [15], p. 337) comment: “Whereas to Staudinger there was a clear
distinction between primary and secondary valences and no attempt was made to
obtain information about the nature of the individual types of bond, the physical
chemistry approach demanded stronger distinction. [. . .] The strength of both
primary and secondary valences was not observed to be constant; instead of this,
it varied according to the structure of the molecules. As far as size was
concerned, a strong secondary valence could therefore very definitely correspond to a weak primary valence.”
On the basis of what we know now, Mark and Meyer were in actual fact “not
completely wrong” [11, p. 48], because it is true that macromolecules can “definitely in suitable conditions form micelles in their solutions too ([11], p. 48; cf. [18],
p. 233). “More or less highly aggregated groups of molecules are also solvated in
colloidal solutions alongside individual molecules, depending on the solvent concentration. Micelles are just as real as individual macromolecules” [15, p. 115],
although the term is nowadays reserved exclusively for “aggregates of small
molecules” [15, p. 82]. Minssen and Walgenbach [20, p. 99] go even further:
“The concept of chemical primary valence with its defined bonding relationships
does not explain all the characteristics of a substance.” Denaturation of enzymes
could, for example, be described best by saying that the primary valence bonds
were maintained, whereas the secondary valence bonds were broken. Minssen and
Walgenbach [20, pp. 60–61] go on: “In the case of what are known as biological
macromolecules, e.g. nucleic acids and ‘proteins’, particularly enzyme proteins, the
sensitivity to heat [. . .] cannot be explained any more via a molecular structure
involving primary valences. [. . .] Staudinger is wrong when he says that the reason
for the instability when exposed to heat is because the molecules ‘disintegrate’ due
to the elimination of primary valences (1926). The introduction of secondary
valences accordingly allows [. . .] the description of more complicated structures
and behavioural patterns than is the case when the theory is reduced to standard
valences.” Staudinger’s concept needed “to be abandoned as too limiting. To this
extent, his opponents are celebrating a belated triumph.”
Courageous Questioning of Established Thinking: The Life and Work of Hermann. . .
103