We present neutron spin echo experiments that address the much debated topic of dynamic phenomena in polymer melts that are induced by interacting with a confining surface. We find an anchored surface layer that internally is highly mobile and not glassy as heavily promoted in the literature. The polymer dynamics in confinement is, rather, determined by two phases, one fully equal to the bulk polymer and another that is partly anchored at the surface. By strong topological interaction, this phase confines further chains with no direct contact to the surface. These form the often invoked interphase, where the full chain relaxation is impeded through the interaction with the anchored chains.

Polymer nanotechnology allows manipulating materials microstructure, morphology and compositional variation on the nanometer scale. Thus, it is able to provide materials for many cutting edge applications, from photonics to medical devices to sensors. This article summarizes recent work on template-based fabrication and on the basic properties of one-dimensional polymeric nanostructures and their inherent advantages over their conventional counterparts. The chemistry and physics relevant for the design of these nanostructured materials are discussed and recent advances emphasized. In particular, highlighting the effects of nanoconfinement on material behavior and putting somewhat greater emphasis on molecular motions. Some examples of one-dimensional-based polymeric nanostructures with promising applications for example in the field of tissue engineering are also presented as well as some aspects concerning recyclability of the used templates

Neutron spin echo has revealed the single chain dynamic structure factor of entangled polymer chains confined in cylindrical nanopores with chain dimensions either much larger or smaller than the lateral pore sizes. In both situations, a slowing down of the dynamics with respect to the bulk behavior is only observed at intermediate times. The results at long times provide a direct microscopic measurement of the entanglement distance under confinement. They constitute the first experimental microscopic evidence of the dilution of the total entanglement density in a polymer melt under strong confinement, a phenomenon that so far was hypothesized on the basis of various macroscopic observations.

In this work, we measure the thermal and thermoelectric properties of large-area Si_0.8Ge_0.2 nano-meshed films fabricated by DC sputtering of Si_0.8Ge_0.2 on highly ordered porous alumina matrices. The Si_0.8Ge_0.2 film replicated the porous alumina structure resulting in nano-meshed films. Very good control of the nanomesh geometrical features (pore diameter, pitch, neck) was achieved through the alumina template, with pore diameters ranging from 294 ± 5nm down to 31 ± 4 nm. The method we developed is able to provide large areas of nano-meshes in a simple and reproducible way, being easily scalable for industrial applications. Most importantly, the thermal conductivity of the films was reduced as the diameter of the porous became smaller to values that varied from κ = 1.54 ± 0.27 W K⁻¹m⁻¹, down to the ultra-low κ = 0.55 ± 0.10 W K⁻¹m⁻¹ value. The latter is well below the amorphous limit, while the Seebeck coefficient and electrical conductivity of the material were retained. These properties, together with our large area fabrication approach, can provide an important route towards achieving high conversion efficiency, large area, and high scalable thermoelectric materials.