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International audienceA new experimental procedure, named " Polymer High Cooling - Optics " and whose performance has been improved, is presented. It allows us to monitor on-line the quiescent crystallization of a polymer film under high and constant cooling rates. With such a set-up, two cooling control modes are available resulting into a range of relatively moderate (from 30 to 500°C/min) and a range of high (from 500 to 1600°C/min) constant cooling rates. The crystallization experiments are observed by polarized light microscopy. Preliminary results are presented. They are obtained on the α-modification of one industrial grade of isotactic polypropylene, under relatively moderate constant cooling rates. Two relevant crystallization parameters are captured, the temperature of crystallization together with the spherulitic growth kinetics versus cooling rate. Accurate data are obtained. As well, they are in good agreement with comparable literature results compiled by Janeschitz-Kriegl [Macromolecules, 2006]. The obtained results seem to match the Hoffman and Lauritzen theory. These discussions validate our " Polymer High Cooling - Optics " set-up in relatively moderate constant cooling rates. Next step is to demonstrate the suitability of this first generation set-up for higher constant cooling rates

The aim of the present work was to investigate the high temperature reaction between Si- C-O fibres and Cl2, and to correlate the carbon layer growth kinetics with their initial composition and structure. Large disparities have been observed between the various materials reaction rates. If a large amount of mixed silicon atom environments increases the reactivity of Si-O-C materials with Cl2, this sole feature does not explain all the experimental results. Traces of heteroelements (Ti, Zr, Al…) or percolated free carbon both appear to bear on the reaction rate. For a better understanding of the fibres reaction behaviour, this study was extended to other model materials (oxycarbide glasses, oxygen-free Si-C fibres, SiC).