Colloidal model

The remainder of this contribution is organized as follows. In section C2.6.2, some well studied colloidal model systems are introduced. Methods for characterizing colloidal suspensions are presented in section C2.6.3. An essential starting point for understanding the behaviour of colloids is a description of the interactions between particles. Various factors contributing to these are discussed in section C2.6.4. Following on from this, theories of colloid stability and of the kinetics of aggregation are presented in section C2.6.5. Finally, section C2.6.6 is devoted to the phase behaviour of concentrated suspensions. 

An important step in tire progress of colloid science was tire development of monodisperse polymer latex suspensions in tire 1950s. These are prepared by emulsion polymerization, which is nowadays also carried out industrially on a large scale for many different polymers. Perhaps tire best-studied colloidal model system is tliat of polystyrene (PS) latex [9]. This is prepared with a hydrophilic group (such as sulphate) at tire end of each molecule. In water tliis produces well defined spheres witli a number of end groups at tire surface, which (partly) ionize to... 

Figure 4. Asphaltene particle peptization effected by adsorbed resin molecules. This physical model is the basis of our asphaltene Thermodynamic-Colloidal Model.

A. Yetrihaj and A. Van Blaaderen A Colloidal Model System with an Interaction Tunable from Hard Sphere to Soft and Dipolar. Nature (2003). 

A.J.G. Blesa, M.A. (1988) The dissolution of magnetite by nitrilotriacetatoferrate(II). J. Chem. Soc. Earaday Trans. I. 84 9-18 Delgado, A. Torrent, J. (2000) Phosphorus forms and desorption patterns in heavily fertilized calcareous and limed acid soils. Soil Sci. Soc. Am. J. 64 2031-2037 Delgado, A.V. Gonzalez-Caballero, F. (1998) Inorganic particles as colloidal models. Effects of size and shape on the electrokinetics of hematite (a-Fe203). Croatica Chemica Acta 71 1087-1104... 

An interesting implication of a colloidal model as suggested by Pratt for UF resins lies in the possible structures that may result from the hardened coalesced material. If colloidal particles do form oligomeric UF condensates, the process of coalescing should be ordered in a systematic way. 

Delgado, A.V., and Gonzalez-Cahallero, E, Inorganic particles as colloidal models. Effects of size and shaj c on the electrokinetics of hematite (0. -Ee2OLj), Croat. Chem. Acta, 71, 1087, 1998. 

Synthesis and Characterization of Colloidal Model Particles Made from Organoalkoxysilanes... 

In this section, experimental results obtained with several different experimental techniques and measured on several different colloidal silica dispersions are described and discussed. The ultimate goal of the investigations is the ability to synthesize stable, monodisperse colloidal model spheres from organoalkoxysilanes with different chemical compositions and surface properties (47-52). 

Inverse-suspension, inverse-emulsion and inverse-microemulsion polymerizations should be developed independently as has been the precedent for oil-inwater polymerizations. This includes explicitly considering the unique chemistry of various emulsifiers, organic phases, monomers and initiators. Furthermore, the chemical and colloidal models for each of the three water-in-oil polymerizations will be specific to a given type of organic phase and a restricted family of emulsifiers. 

The above studies have demonstrated that various photosensitizers, in conjunction with many available experimental techniques, can be used to probe different regions of the colloidal model membranes systems. Careful choice of sensitizers is important in determining different regions of the micelles, reverse micelles, or liposomes, and their different dynamic and structural features. 

R. O. James, P. J. Stiglich, and T. W. Healy, The Ti02/aqueous electrolyte system Applications of colloid models and model colloids, in P. H. Tewari, op. cit. °... 

Fig.1 Colloidal model of magnetic nanoparticles and schematic representation of an elastic collision between particles (a) water-based ferrofluid, (b) oil-based ferrofluid...

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