Aggregates self-assembly

Li H, Bazan GC (2009) Conjugated oligoelectrolyte/ssDNA aggregates self-assembled multicomponent chromophores for protein discrimination. Adv Mater 21 964-967... 

Simard, M., Su, D., and Wuest, J. D., Use of hydrogen bonds to control molecular aggregation. Self-assembly of three-dimensional networks with large chambers, J. Am. Chem. Soc. 113, 4696-4698(1991). 

The vCH2 temperature dependence has been used in determining the melting point of a wide range of LB films [503, 515-519] and SAMs [370, 520]. The vCH2 molecular area dependences have been used to study the mesophase transformations in L monolayers [508, 521-524], while the VCH2 time dependences have been helpful in studies of the kinetics of aggregation (self-assembly)... 

For small molecular aggregates, self-assembled aggregates are usually in stable thermodynamic equilibrium, and can be discussed mostly from the viewpoint of static intermolecular interactions. However, as it is shown in... 

Solvent cast films of PS-fc-P4VP/polyimide complex aggregates self-assembled into microporous films are shown in Figure 14.13. 

Maointosh F C, Safran S A and Pinous P A 1990 Self-assembly of linear aggregates the effeot of eleotrostatios on growth Europhys. Lett. 12 697-702... 

Manne S 1997 Visualizing self-assembly Force microscopy of ionic surfactant aggregates at solid-liquid interfaces Prog. Colloid Polym. Sol. 103 226-33... 

In systems of LP the dynamic response to a temperature quench is characterized by a different mechanism, namely monomer-mediated equilibrium polymerization (MMEP) in which only single monomers may participate in the mass exchange. For this no analytic solution, even in terms of MFA, seems to exist yet [70]. Monomer-mediated equilibrium polymerization (MMEP) is typical of systems like poly(a-methylstyrene) [5-7] in which a reaction proceeds by the addition or removal of a single monomer at the active end of a polymer chain after a radical initiator has been added to the system so as to start the polymerization. The attachment/detachment of single monomers at chain ends is believed to be the mechanism of equilibrium polymerization also for certain liquid sulphur systems [8] as well as for self-assembled aggregates of certain dyes [9] where chain ends are thermally activated radicals with no initiators needed. 

The reasons for self-assembly and the mechanisms necessary conditions for the aggregation into micelles, mono- or bilayers, structure of aggregates, distribution of aggregation numbers, etc. 

Some of the more remarkable examples of this form of topologically controlled radical polymerization were reported by Percec et cii.231 234 Dendron maeromonomers were observed to self-assemble at a concentration above 0.20 mol/L in benzene to form spherical micellar aggregates where the polymerizable double bonds are concentrated inside. The polymerization of the aggregates initiated by AIBN showed some living characteristics. Diversities were narrow and molecular weights were dictated by the size of the aggregate. The shape of the resultant macroniolecules, as observed by atomic force microscopy (ATM), was found to depend on Xn. With A, <20, the polymer remained spherical. On the other hand, with X>20, the polymer became cylindrical.231,232... 

AB diblock copolymers in the presence of a selective surface can form an adsorbed layer, which is a planar form of aggregation or self-assembly. This is very useful in the manipulation of the surface properties of solid surfaces, especially those that are employed in liquid media. Several situations have been studied both theoretically and experimentally, among them the case of a selective surface but a nonselective solvent [75] which results in swelling of both the anchor and the buoy layers. However, we concentrate on the situation most closely related to the micelle conditions just discussed, namely, adsorption from a selective solvent. Our theoretical discussion is adapted and abbreviated from that of Marques et al. [76], who considered many features not discussed here. They began their analysis from the grand canonical free energy of a block copolymer layer in equilibrium with a reservoir containing soluble block copolymer at chemical potential peK. They also considered the possible effects of micellization in solution on the adsorption process [61]. We assume in this presentation that the anchor layer is in a solvent-free, melt state above Tg. The anchor layer is assumed to be thin and smooth, with a sharp interface between it and the solvent swollen buoy layer. 

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