Alcatel Alsthom Compagnie Generale D'electricite

Alcatel

Nexans

Francoise Ducatel

Claudette Audry

Madeleine Prigent

Gerard Duperray

Jose-Marie Lopez-Cuesta

Aziza Gouchi

Agnes Durin-France

Grard Duperray

Laurent Ferry

Carlo Triboulet

The present invention provides a composition possessing high resistance to fire propagation, the composition comprising a base polymer and a fireproofing additive containing a metal hydroxide. In the composition, said fireproofing additive further contains a compound based on a carbonate of a metal from group IA of the periodic table of elements coated in a metal salt, said compound constituting at least 10% by weight of fireproofing additive.

Composition presenting high resistance to the propagation of fire

A process for dereticulating a cross-linked polymeric material, such as cross-linked polyethylene from scraps of electric cable coatings or from unused cable coatings through a mechanical mixing cycle, wherein the cross-linked material is subjected to a specific power per mass unit such as to induce shear stresses in the material itself and temperatures higher than pre-established minimum levels. At the end of this cycle the material goes back to a thermoplastic state that may be substantially regarded as thermoplastic; then, following granulation, cooling, drying and sacking, the material will be ready for re-use, either alone or mixed with virgin polymers, according to usual operating technologies for thermoplastic materials. Eventually, the mechanical mixing cycle may be preceeded by a preliminary crushing cycle of the cross-linked polymeric materials to be treated. Preferably, the mixing cycle is carried out in a twin-screw extruder with special screw and temperature profiles.

Recycling process of a cross-linked polymeric material, in particular

A method of preparing a powder of YBaCuO [phase 123] suitable for forming by drawing-lamination, which includes:

Method of preparing YBa.sub.2 Cu.sub.3 O.sub.7 powder for forming by

A process for obtaining precursors for high critical temperature superconductor ceramics by precipitating salts which are insoluble in water comprises the following stages: A starting solution of soluble salts is prepared in which the cations are in the stoichiometric proportions of the required superconductor phase. A first full precipitation is carried out of a first series of cations at a first value of pH. The first precipitates obtained is filtered out and washed and the filtrate is retained. The pH of the filtrate is changed to a second value and the residual cations are precipitated. The second precipitate is filtered. The first and second precipitates are homogenized. The product obtained is dried, calcined, and ground.

Process for obtaining precursors for high critical temperature

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Bonnelles, France

Francoise Ducatel