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Abstract: Bitumen, the residue of oil distillation and applied e.g. as binder in asphalt pavements displays a rich microstructure at the bitumen surface-to-air surface with several clearly distinguishable phases. However, uncertainty still remains whether this micro-structure is just present at free surfaces or a similar structure exists in the bulk of the material. Two new experimental techniques in bitumen research (i) one based on Atomic Force Microscopy (AFM) on a freeze–fracture surface and (ii) one technique employing a Scanning Acoustic Microscope (SAM) offer the required spatial resolution and show the presence of two phases in the bulk showing similarities with the known surface structures in bitumen. [Copyright &y& Elsevier]

Novel phenyl benzoate-based and biphenyl-based liquid crystalline thiol-ene monomers were synthesized and their properties investigated. By varying the bridging unit and spacer length, the type of mesophase can be tuned from the low ordered nematic and smectic A phase in the case of the phenyl benzoate-based monomers, to the highly ordered crystal E phase for the biphenyl-based monomers and their corresponding bromo precursors. We investigated the degree of order of the phenyl benzoate-based materials using the Haller method. Possible premature polymerization of these monomers was examined by size exclusion chromatography. The materials exhibit low transition temperatures and a high stability at typical handling times and temperatures. Consequently, these monomers are useful for in situ polymerization with anisotropic inert solvents, which could potentially lead to new architectures and enhanced electro-optical properties of devices. The use of the biphenyl-based monomers appears to be of limited use for polymerizations in anisotropic solution. However, as a result of their intrinsic high degree of molecular order, these monomers form a particularly interesting class of reactive materials that can be bulk polymerized to give main chain polymers with highly defined mechanical and optical or electro-optical properties. [ABSTRACT FROM AUTHOR]

Comments on the potential applications of the NiTinol nickel-titanium compound in the field of shape memory and superelastic technologies (SMST). Characteristics of the compound similar to a binary alloy which can change between two crystal structures with only very little limits; Change between the phases of the compound which gives the material innovative possibilities for all kinds of applications.