Studies on Novel Surfactant-Free Polystyrene Nanoparticles Formed in Microphase Inversion
نویسندگان
چکیده
Randomly carboxylated polystyrene ionomers are insoluble in water. However, we found that when their tetrahydrofuran (THF) solutions are added into an excess of water or vice versa, the ionomer chains can undergo a microphase inversion to form surfactant-free colloidal nanoparticles stable in water. In this study, a combination of static and dynamic laser light scattering (LLS) was used to study the influence of various experiment conditions, such as the initial ionomer concentration in THF, the degree of carboxylation, the type of counterion, the composition of the THF/water mixture, and the order of mixing the ionomer THF solution with water, on the formation and size distribution of the
منابع مشابه
Formation of novel polymeric nanoparticles.
We have found that not only block copolymers but also ionomers can self-assemble in a selective solvent to form surfactant-free nanoparticles. The self-assembly can be induced by chemical reaction, polymer-polymer complexation, and microphase inversion in addition to the temperature. A recently developed microwave method for the preparation of uniform surfactant-free polymeric nanoparticles is ...
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