To address this topic and further investigate all the reaction pathways that blocked isocyanates could be subjected to (Figure 4, (8)), in addition to simple thermal deblocking, the impact of catalysts, chain extenders with different nucleophilicity
(e.g., polyols and amines) or their combination were investigated.
The accelerated aging occurs because the reactivity of the amine depends upon the nucleophilicity
of the amino group .
They address electronic structure principles, such as the electronegativity equalization principle, harness equalization principle, electrophilicity equalization principle, nucleophilicity
equalization principle, and studies based on these electronic structure principles.
This reflects the high eletrophilicity of PBTCA and high nucleophilicity
Orth, "The importance of methyl positioning and tautomeric equilibria for imidazole nucleophilicity
," Chemistry-A European Journal, vol.
The maximum values of relative nucleophilicity
index ([s.sup.+.sub.k]/[s.sup.-.sub.k]) and relative electrophilicity index ([s.sup.-.sub.k]/[s.sup.+.sub.k]) are used to define, respectively, the probable sites of nucleophilic and electrophilic attacks.
Jamart-Gregoire, "A conceptual DFT Study of hydrazino peptides: assessment of the nucleophilicity
of the nitrogen atoms by means of the dual descriptor [DELTA]f(r)," Journal of Molecular Structure, vol.
In MEP analysis, electrophilicity and nucleophilicity
is explained on the basis of different color codes, red color indicates nucleophilic and blue color reflects electrophilic site .
The global reactivity indices (electronic chemical potential [mu], chemical hardness [eta], global electrophilicity [omega], global nucleophilicity
N) were estimated according to the equations recommended by Parr [15, 16] and Domingo [17, 18].
The thermal stability of ionic liquids is influenced by anion nucleophilicity
. For imidazolium salts with a [Cl.sup.-] anion, the first step of decomposition is reported to occur between 250 and 300 [degrees]C (Fig.