Properties of Dendrimers

In solution, dendrimers form close-packed, globular, or spherical shapes when the molecular weight is high enough, unlike the expanded flexible coil structures of linear polymers. This has a significant effect on the rheological properties, e.g., the 

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Also, from the dendrimer point of view, the introduction of mechanical bonds to dendrimers has an enormous potential to alter the properties of dendrimers in a controlled way. For example, in the synthesis of a Type II rotaxane dendrimers, the wheel components are introduced to the terminal groups of the dendrimers. This can improve the solubility of dendrimer in organic and/or aqueous media due to the formation of complexes soluble in such solvents. 

An important property of dendrimers is the presence of internal cavities in which ions or neutral molecules can be hosted [68]. Such a property can potentially be exploited for a variety of purposes, which include catalysis and drug delivery. 

Chiroptical Properties of Dendrimers with Chiral End Groups. .. 91... 

McGrath et al. have also thoroughly studied the chiroptical properties of dendrimers such as 40. They compared the optical activities of the series of 1st-, 2nd- and 3rd-generation compounds of type 40, considering the molar rotation per chiral unit ([ ]D/n) [75]. A big difference of the values was found between the generations which could possibly indicate chiral conformations inside the dendrimers, that enhance the optical rotation values per unit when... 

Optical properties of dendrimers bearing eight chromophores have been examined by single molecule spectroscopy techniques. It is especially exciting that variations in the spectra are recorded if one of these dendrimers is observed for a period of time under continuous irradiation.1481 The fluorescence intensity of the dendrimer nanoparticle also jumps between discrete emissive levels. All these findings suggest the existence of strong electronic interactions between several perylene imide chromophores within one dendrimer and provide new... 

Frechet, J. M. J., Hawker, C. J., Synthesis and properties of dendrimers and hyperbranched polymers, in Aggarwal, S. L. and Russo, S. (eds), Comprehensive Polymer Science, Second Supplement, Elsevier Science, Oxford 1996, pp. 71-133. 

Dendritically branched molecules have shapes and interactions that are radically different from traditional linear polymers. SANS, SAXS and TEM have been used to measure the properties of dendrimers and a generic understanding of their properties has emerged. Five technologically important questions on the nature of dendrimers have been posed and generalized observations can be made. 

Compared to dilute solution viscometry and to some extent to bulk rheology, the flow properties of dendrimers in concentrated solutions have been the least investigated area of dendrimer rheology. In fact, with the notable exception of some recent data on generation 4 PPI in water [22] the only [32] reported... 

PHOTO-LUMINESCENCE PROPERTIES OF DENDRIMER METAL NANOCOMPOSITES... 

Very recently, highly regular, highly controlled, dense branching has been developed. The resulting dendrimers often have a spherical shape with special interior and surface properties. The synthesis and properties of dendrimers has been reviewed (see e.g. G.R. Newkome et al. Dendritic Molecules , VCH, 1996). In this series, a chapter deals with the molecular dimensions of dendrimers and with dendrimer-polymer hybrids. One possible development of such materials may be in the fields of biochemistry and biomaterials. The less perfect hyper-branched polymers synthesized from A2B-type monomers offer a real hope for large scale commercialization. A review of the present status of research on hyperbranched polymers is included. 

In this chapter we discuss an aspect of dendrimers that has yielded a rich body of fundamental information about the properties of dendrimers as well as... 

By manipulating the chemical properties of dendrimer functional groups, hydrophilic guest molecules can be dissolved in nonpolar solvents and hydro-phobic molecules can be dissolved in polar solution. This is possible because, independent of an encapsulated guest, dendrimers terminated in hydropho-... 

The physical properties of dendrimers such as solubility, arising from their hyperbranched globular shapes and the peripheral groups, can be modified by end-group modification. In core-functionalized dendrimers, the immiscibility of the wedges with a solvent enables precipitation and subsequent separation by filtration. 

Suek NW, Lamm MH. Effect of terminal group modification on the solution properties of dendrimers a molecular dynamics simulation study. Macromolecules 2006 39 4247-4255. 

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