Aggregation behavior in solution

High molecular weight polysiloxanes modified with mono-, di- or oligosaccharides showed different aggregation behavior in solution, depending on the detailed chemical structure of the carbohydrate moiety and its stereochemistry [88],... 

The complexes exhibited different behavior in solution. The gold-thallium derivative showed a shift of the emission to 536 nm when the measurement was carried out in frozen solution. This was explained by a higher aggregation of [Aull(MTP)2] units in the solid state compared to the situation in solution. In the case of the Au-Pb compound, the emission spectrum showed a strong dependence on the aggregation state and temperature. Thus, the emission band in TH F solution, which appeared at 555 nm (298 K) (x = 57 ns), was shifted to 480 nm in frozen solution (x = 2.3 ps) or appeared at 752 nm in solid state (x = 22 ns). As with the thallium complex, the shift to high energy in solution may have been related to the polymeric structure of the complex in the solid state that was not reproduced in solution. 

Benzylalkali metal compounds exist as aggregate structures in most solutions. NMR and UV-visible spectrophotometry are useful techniques for elucidating these solution-phase structures. Benzyllithium is dimeric in benzene solution the carbanion charge is probably more delocalized in THE solution. NMR studies of a THE solution of a-(dimethylamino)benzyllithium reveals a dynamic equilibrium between the and -structures (18) and (19). The monohapto isomer (18) is preferred thermodynamically.The effects of various donor ligands on this type of dynamic behavior in solution is continually being studied. ... 

Guoyong, W. Zhiping, D. Qiuxiao, L. Wei, Z., Carbohydrate-Modified Silox-ane Surfactants and Their Adsorption and Aggregation Behavior in Aqueous Solution. J. Phys. Chem. C 2010,114, 6872-6877. 

Matsumoto, K., Kubota, M., Matsuoka, H., and Yamaoka, H. (1999) Water-soluble fluorine-containing amphiphihc block copolymer Synthesis and aggregation behavior in aqueous solution. Macromolecules, 32,7122-7127. 

Du Z, Li E, Cao Y, Li X, Wang G (2014) Synthesis of trisUoxane-taUed surface active ionic liquids and their aggregation behavior in aqueous solution. CoUoids Surf A Physicochem Eng Asp 441 744-751. doi 10.1016/j.colsurfa.2013.10.004... 

A new block type of dendritic polymer has been prepared by Meijer and co-workers [54,55]. Polystyrene-Z>/ocA -dendron (PS-dendr-(COOH) ) was prepared by a divergent dendrimer synthetic methodology using an amine-functionalized polystyrene of well-defined structure as the core for the synthesis of a poly(propylene imine) dendrimer. A representation of the structure is shown in Figure 2. It was reported that the amphiphilic dendrimer exhibited a remarkable generation-dependent aggregation behavior in a variety of salt solutions regardless of pH. 

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