We measure Young's modulus of a free polyelectrolyte multilayer film by studying osmotically induced swelling of polyelectrolyte multilayer microcapsules filled with the polyelectrolyte solution. Different filling techniques and core templates were used for the capsule preparation. Varying the concentration of the polyelectrolyte inside the capsule, its radius and the shell thickness yielded an estimate of an upper limit for Young's modulus of the order of 100 MPa. This corresponds to an elastomer and reflects strong interactions between polyanions and polycations in the multilayer.

By using a combination of atomic force and confocal microscopy, we explore the effect of molecular weight and aging on the mechanical properties of polyelectrolyte multilayer microcapsules. Within the variability of experimental data, the force vs relative deformation curves and images from confocal scanning of the deformed capsules were found to be the same for all molecular weights used. The freshly prepared polyelectrolyte microcapsules were found to be stiffer than the aged ones. This time softening or aging was shown to be due to faster drainage of the inner solution. Such a rapid drainage is probably caused by an enhanced fragility (or a decrease in the rupture strength) of the multilayer and is observed despite a detected reduction of nanopore size and number. These results are consistent with the concept of a rubbery (elastomeric) state of the multilayer.

A series of technically and economically important element chlorides-such as SiCl4, BCl3, AlCl3, FeCl2, PCl3 and TiCl4-was synthesized through reactions between hydrogen chloride and the corresponding element oxides in the presence of different carbon sources with microwave assistance. This process route was optimized for demonstration purposes for tetrachlorosilane formation and successfully demonstrates the broad applicability of various silicon oxide-containing minerals and materials for carbohydrochlorination. The chlorination reaction occurs at lower temperatures than with conventional heating in a tubular oven, with substantially shorter reaction times and in better yields: quantitatively in the case of tetrachlorosilane, based on the silicon content of the starting material. The experimental procedure is very simple and provides basic information about the suitability of element compounds, especially element oxides, for carbohydrochlorination. According to the general reaction sequence element oxide-->element-->element chloride used in today's technology, this one-step carbohydrochlorination with hydrogen chloride is considerably more efficient, particularly in terms of energy input and reaction times, avoiding the isolation of the pure elements required for chlorination to give the element chlorides with use of the more corrosive and toxic chlorine gas.

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