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In this work, PEO17−OPV3, a light-emitting amphiphilic molecule, was served as a structure-directing agent to fabricate the nano-hollow rods and microspheres through self-assembling with titania precursors. FT-IR and EDX were employed to examine the composition of these hybrid materials. In the beginning, the microspheres of ∼1 μm composed of bundles of nanorods were observed by SEM. By grinding the microspheres, isolated hollow rods of ∼100 nm in diameter were observed and investigated by TEM and AFM. Two sets of crystalline planes, rutile (110) and (101), in the skin of hollow rods were resolved. As we stained the OPV3 packing domains of hollow rods with RuO4, the rutile layer of the skin was ripped off, and the stained inner layer of ∼20 nm diameter was clearly identified. On the basis of the experimental evidence, we proposed a cylinder with a core−shell skin model to explain the formation of nano-hollow rods.

In semidilute polyelectrolyte solutions, reduced viscosity (ηr) versus concentration (cp) plots follow the relation ηr ∼ cpn, where n is dependent on the chain conformations. Using de Gennes' scaling arguments, we show that the average end-to-end distance of a polyelectrolyte chain, R = Nνa (N is the number of mers in a chain and a is the length per mer), can be estimated by ν = (n + 2)/3(n + 1). The new scaling relation was employed to estimate the chain conformations of poly(xylylene tetrahydrothiophenium chloride) (PXT) in salt-free and salt-containing aqueous and methanol solutions.

The conductivity of sodium poly(styrenesulfonate) solution was found to increase during dialysis against water as indicated by the in-situ conductivity measurements at a concentration of c = 0.1 g/L, which is in the dilute/semidilute region. To interpret this unexpected phenomenon, the domains of polyion chains and their aggregates are assumed to have a uniformly charged density. Although the aggregation resulted from the higher attractive forces rather than the repulsion between the polyion chains, their size was determined by the counterbalance of ionic osmotic forces due to the fact that the interior of aggregated domains has more counterions than the exterior. When the polyelectrolyte solution was dialyzed against water, extra osmotic forces acted on the solution due to Donnan's effects. On the basis of the mean field theory and above arguments, the increase of conductivity during dialysis was interpreted in terms of the aggregation of polyions in the aqueous solution.