Rhone-poulenc Chimie

Centre National De La Recherche Scientifique

Universitë De Bordeaux

Societe Nationale D'etude Et De Construction De Moteurs D'aviation-snecma

L'etat Francais, Represente Par Le Delegue General Pour L'armement

Commissariat &#xc0; L'&#xc9;nergie Atomique Et Aux &#xc9;nergies Alternatives

Marc Birot

Jacques Dunogues

Jean-Paul Pillot

Francoise Duboudin

Pierre Olry

Rene Pailler

Roger Naslain

Yves Laurent

Eric Pasquinet

Xavier Bourrat

Ren&eacute; Pailler

Odile Babot

Paul L'Haridon

Herve Deleuze

Raphael Bodet

Laurence Bois

Olivier Manfe

Patrick Pujol

Claire Forgacz

Fabrice Audouin

Olivier Besnard

An interconnected microcellular material, a method for preparing said material using low-value waste from the paper industry, such as industrial lignin, and the use thereof for the production of items such as catalysts, filters or absorbent elements.

Interconnected microcellular material made of industrial lignin and method for preparing same

Preparation of mesophasic polyborazylene mesophasic polyborazylene and use as a BN precursor

A boron and silicon oxynitride obtained by preparing a polyborosiloxane precursor, conducting nitriding pyrolysis of the precursor to obtain an amorphous boron and silicon oxynitride, and optionally conducting additional pyrolysis to obtain a crystallized boron and silicon oxynitride. The polyborosiloxane precursor is prepared by condensation, in the presence of a catalyst, of (2) a polychlorosilane represented by the formula R,R,SiCl,in which the substituents R,and R,are identical or different and each represents a hydrogen atom, a chlorine atom, a linear or branched alkyl or alkenyl or alkynyl radical having 5 or less carbon atoms, or an aryl or aralkyl radical having 6 to 18 carbon atoms, with (2) an alkyl borate represented by the formula (R,O),B in which R,represents a linear or branched alkyl radical having 1 to 5 carbon atoms.

Method of preparing silicon and boron oxynitrides

Silicon carbonitride ceramic materials are produced by (a) hardening a fusible polycarbosilane containing at least two .tbd.SiH groups per molecule by intimately contacting such fusible polycarbosilane with an effective hardening amount of the vapors of sulfur, next (b) heat treating the infusible polycarbosilane which results under an ammonia atmosphere to such extent as to introduce nitrogen into the infusible polycarbosilane without completely removing the carbon therefrom, and then (c) heat treating the nitrogenated polycarbosilane in a vacuum or in an inert atmosphere to such extent as to essentially completely convert it into a ceramic silicon carbonitride.

Conversion of polycarbosilanes into silicon carbonitride ceramics

Silicon nitride ceramic materials are produced by (a) hardening a fusible polycarbosilane containing at least two .dbd.SiH groups per molecule by intimately contacting such fusible polycarbosilane with an effective hardening amount of the vapors of sulfur, and then (b) pyrolyzing the infusible polycarbosilane which results under an ammonia atmosphere.

Conversion of polycarbosilanes into silicon nitride ceramics

Extrudable pre-ceramic polycarbosilanes are prepared by intimately contacting a crude polycarbosilane containing a fraction of high molecular weight polymers (e.g., molecular weights greater than about 25,000) with ethyl acetate, whereby selectively dissolving desired extrudable polycarbosilane essentially devoid of such fraction of high molecular weight polymers in the ethyl acetate, and then recovering such dissolved polycarbosilane from the ethyl acetate solvent.

Extrudable pre-ceramic polycarbosilanes

Growing community of inventors

Talence, France

Marc Birot