| Abstract
| - After briefly discussing the particularity of the adsorption process of PMMA aggregates in terms ofaggregative adsorption, the patterns formed by poly(methyl methacrylate) (PMMA) stereocomplexes atthe surface of silicon wafers, glass, and mica were investigated by tapping mode atomic force microscopy.The effects of the solvent nature, PMMA concentration, i/s-ratio, and surface nature on the morphologyof the stereocomplex layer at a surface were addressed. The aggregation phenomena are well describedby the diffusion-limited cluster−cluster aggregation model (DLA) and the fractal exponent D calculated.Solvent was shown to play a major role on the structure of the polymer assembly observed on silicon. Thei/s-ratio strongly influences the fractal exponent D, since slow or fast aggregation can be involved. Dilutepolymer solutions were used and the concentrations were varied from 0.1 to 1 g/L in acetone to reach a2D network of connecting aggregates. The size of the aggregates increases with the PMMA concentrationand is always higher than the size of the aggregates in solution measured by light scattering. This is theresult of an enhanced surface aggregation of the polymer assembly indicated by the difference in size ofthe aggregates observed on different substrates of varying surface energy.
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