Stacking oligo

As with the bicyclo[4.4.1]undecane-scaffolded oligothiophenes, the stacked oligo(phenylene ethynylene)s exhibit two one-electron oxidations, both at lower potential than the corresponding unstacked oligomer, as shown in Fig. 43. 

Since the first preparation of triple-decker complexes, the possibility of constructing oligo-decker and poly-decker species [quadruple-decker (95), multiple-decked stacked compounds (55)] has received attention. At this time, few published data are available. 

In a physicochemical study of oligo- or polynucleotides, it has been reported that Hypochromicity, depends on the degree of polymerization [61]. The value of native DNA is about 60%, which corresponds to the Hypochromicity, of the absorption of its mononucleotides [60]. The present result indicates that the purine rings may intramolecularly stack by themselves in an aqueous solution... 

The folding of oligo(/n-phenyleneethynylene)s (Figure 4) into helical stacks driven by solvophobic effects was reported by Moore and co-workers.46 These... 

Ray et al. [42] had successfully prepared PLA/MMT nanocomposites by simple melt extrusion of PLA wherein the silicate layers of the MMT were intercalated and randomly distributed in the matrix. They also showed that the incorporation of very small amounts of oligo( -caprolactone) (o-PCL) as compatibUizer in PLA led to a better parallel stacking of the silicate layers and also much stronger flocculation due to the hydroxylated edge-edge interaction of the silicate layers. The PLA/MMT nanocomposites also exhibited remarkable improvement of materials properties in both solid and melt states compared to the matrix without MMT. 

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