Jean-Jacques Becker historien. Pour comprendre le XXe siècle européen

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La politique et la guerre. Pour comprendre le XXe siècle européen. Hommage à Jean-Jacques Becker

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Catalyzed ring opening of epoxides: Application to bioplasticizers synthesis

International audienceThe ring opening of mono, di or tri-substituted epoxides by acetic anhydride to corresponding diacetates is catalyzed by weak bases such as hydrotalcite in the carbonated form. This reaction is performed at 423 K without solvent and the solid catalyst is reused after simple regeneration for 4 runs with constant conversion. Ring-opening of methyl oleate epoxide leads to the formation of useful diacetate methyl oleate. Starting from vegetable oils, polyacetate derivatives are prepared in three catalytic steps (methanolysis, epoxidation then ring opening). Plastisol was prepared by mixing these products with PVC and their rheological properties were evaluated. The recorded data show that they can act as bioplasticizer with similar behaviour as phthalate reference. (c) 2010 Elsevier B.V. All rights reserved

Le musée d’histoire en France entre traditions nationales et soucis identitaires

The museums of history have known some spectacular changes in contemporary\ud France for two decades. New buildings have been constructed, and a lot of old ones have\ud been renovated. The study of some specific cases, for example the museums devoted to the\ud history of World War II, or to the history of migrations, demonstrates how museology is\ud nowadays far from the pure illustration of erudite knowledge. The ideal museum of french\ud history is today a museum very concerned by the present state of affairs, the political agenda\ud or the social agency. Its aims are linked to the consciousness of « heritage » in the contemporary\ud society. One difficulty is not to becoming a commercial product, a kind of entertainment, or of\ud « edutainment » for kids. The challenge is to play the role of a place of memory, or even to\ud figure a tool for collective thinking about the new stakes of national identity