Oligomer length

Because of the role of precursor structure on film processing behavior (consolidation, densification, crystallization behavior), the reaction pathways are typically biased through the use of the catalyst, which is simply an acid or a base. This steers the reaction toward an electrophilic or nucleophilic attack of the M—OR bond.1,63 Hydrolysis sensitivity of singly or multiply hydrolyzed silicon alkoxides is also influenced by the catalyst, which contributes to the observed variations in oligomer length and structure. Figure 2.3b illustrates... 

Coarse-grained model of Nafion with 20-unit oligomer (length 30 nm). 

The presence of a folded state was evaluated by studying the spectroscopic properties of 1-9 in both chloroform and acetonitrile, which are good and bad solvents, respectively [23,25,26]. The molar absorptivity of 1-9 in chloroform increased in a linear fashion with respect to oligomer length (Fig. 2). However, when UV spectra were taken in acetonitrile two linear trends were identified. Oligomers 1-5 displayed a slope similar to that observed in chloroform, while 4-9 displayed a much smaller slope. The decrease in slope is... 

Fig. 20 Plot of log against oligomer length. The binding affinity of 40 reaches a maximum value with the 20-mer (41) and 22-mer (42)...

Fig. 22 Plot of log values (solid squares and circles) and modeled heat of association (open squares and circles) against oligomer length for ligands 40 (circles) and 44 (squares). Experimental values for 40 are taken from ref. [58] for direct comparison to 44...

Figure 8. Comparison of Number of Bonds per Bead for a) Original Wyodak Coal (initial crosslinks = 290, initial extract yield = 7.4%, oligomer length = 10 and hard bonds = 200) and c) Modified Wyodak Coal (initial crosslinks = 600, initial extract yield = 21.5%, oligomer length = 4 and hard bonds = 0). b and d Compare the Fluid Fraction and Extract Yield for Original Wyodak Coal and Modified Wyodak Coal, Respectively.

In polyionic complexes, formed by polymeric amines and sodium oligophosphates, an sigmoid dependence of the effective constant of binding on oligomer length is observed (Fig. 24). The critical degree of polymerization of is equal to 792 for the system sodium polyphosphate-poly(dimethylaminoethyl methacrylate). It should be... 

Figure 70. Plot of AG (CI I CN) vs oligomer length for 23 (n= 12) through 23 (n = 18). The linear equation used to fit the data is given by AGICTLCN) = 5.1—0.68/j (kcahmol-1).

Figure 88. Plot of log Kn versus oligomer length n. The binding affinity of 39 reaches a maximum value with 23 (n = 20 and 22). All measurements were recorded in a mixed solvent of 40% H2O in CH3CN (by volume) at 294 1 K. [39] = 4.2 fiM.

These subunits were combined in the synthesis of several compounds of varying oligomer length (43, 44, 45 R = Me, n-Hex). 

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