Papers by Keyword: Polymer Surface

Abstract: The coating of polymer surfaces with ceramics up to now is basically only accomplishable by vacuum-based technologies such as sputtering, because the thermal load is low compared to other methods such as sol-gel processing. Since the investment costs for the equipment required are considerably high and the coating is limited to line-of sight deposition, simple and cost-effective processing routes are sought. In all higher organisms inorganic materials are synthesized at ambient temperatures under physiological conditions. Therefore the study of biomineralization processes has gained considerable academic attention in the last decades. One of the key features of inorganic material deposition in vito is the interaction between supersaturated solutions and specifically modified surfaces. Following this paradigm so-called bio-inspired approaches can be developed which go beyond the current limitations of synthetic techniques. One example is the mineralization of planar polymer surfaces with TiO2 at 50oC. Using polystyrene latex particles as templates, all four stages commonly found in natural biomineralization can be emulated in a completely artificial system.

Abstract: The determination of electrokinetic properties such as the zeta-potential of polymer samples with classical methods is laborious and time-consuming. For this reasons, a reliable, fast, and easy to use measurement system based on streaming potential measurement was developed. In this novel measurement system, streaming potential is created by an oscillating flow of a small amount of electrolyte solution through the sample media. In addition, this setup allows direct titration and therefore time-resolved monitoring of changes in zeta-potential in a seconds timescale. With this instrument, the concentration- as well as the time-dependent adsorption behaviour of various non-ionic, anionic and cationic surfactants on a novel, regenerated cellulosic polymer was investigated. This new cellulose-based, fibrous textile polymer is permanently cationised, not only at the surface but throughout the whole fibre. The results show that even very low concentrations of surfactant, due to its charge and chemical composition, highly influence the surface charge of the polymer in a large range. Furthermore, the results for this new textile material are compared with other textile fibres, e. g. wool.