Keywords: Crosslinking / Cyclization / Dendrimers / IsomerizationIn addition to the model compounds 4a and 4b, the dendrimers 11 and 14 with trans-stilbene chromophores in the core and on the periphery of the dendrons were prepared and their photochemistry was studied in solution and in neat films. Due to the flexibility of the arms, intramolecular and intermolecular CC bonds are formed on irradiation. Thus, the generation of nanoparticles, which represent small oligo-

Thermophysical and thermomechanical properties of UV-cured Norland Optical Adhesives (NOA65) and low molecular weight Liquid Crystal E7 systems were investigated. Thin films of Polymer Dispersed Liquid Crystal were prepared by Polymerization Induced Phase Separation and UV-curing. Phase diagrams were established using Polarized Optical Microscopy and DSC to determine the lines of nematic to isotropic phase transition as well as the glass transition temperature changes with the system composition. Mechanical measurements were performed in the static and dynamic modes to determine the moduli in terms of the curing time, the temperature and the amount of low molecular weight liquid crystal molecules. Thermomechanical measurements were found to overestimate the glass transition temperature as compared to calorimetric data. Variations of the Young's modulus and the molecular weight defining the mesh size of the network were analyzed in terms of the curing time and liquid crystal concentration.

The knowledge of temperature profiles in space and time throughout tumored tissues is a crucial step in designing efficient hyper thermal therapies for cancer. The present work is a contribution in modeling these profiles based on distributions of nanospheres and pointlike particles. Heat diffusion equations are solved under different conditions to rationalize the effects of boundary conditions and size of heating particles. The case of pointlike heating sources is found to be much simpler and more convenient to trace back the effects of metabolism and blood perfusion.

The thermophysical properties and phase behavior of polymer/liquid crystal systems are reviewed. These systems, often called polymer-dispersed liquid crystals (PDLCs), have a variety of applications encompassing electrically activated windows with controlled light transmission, display panels, fiber optics, and multiplexing devices for telecommunication systems. Most applications rely on specific electro-optical responses that in turn depend on the phase behavior and thermophysical properties in addition to the morphology and dimensions of the LC domains. This is why a detailed study of thermophysical properties is necessary to better comprehend the performance under practical conditions in applications. This paper reviews the theories used to understand these properties and gives some experimental examples used as tests for the theory. A biased selection of experimental studies already reported in the literature has been chosen as a basis for discussing the main features of the properties of polymer/liquid crystal composites and assessing the applicability of the models. These examples use a variety of polymers with different architectures, including acrylates, siloxanes, and thiolene monomers, together with LCs exhibiting different kinds of order. † Part of the "Josef M. G. Barthel Festschrift".

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