Introduction

The invention relates to a method for producing silicon oxycarbide fibers by pyrolysis of preceramic precursors. Said method comprises the following steps: spinning of a composition comprising a silicone polymer and a reticulating agent, chemical reticulation of the fibers and pyrolysis at a temperature between 800 and 1400° C in non-oxidizing atmosphere.

Technical features

The new technology relates to a method for producing silicon oxycarbide fibers by pyrolysis of preceramic precursors. Silicon oxycarbides have a structure derived from silica glass in which some of the bridging silicon atoms are replaced by tetracoordinated C atoms. Such substitution leads to improved mechanical properties, higher viscosity and allows to use SiOC at higher temperature compared to the starting silica glass. The method comprises the spinning of a composition comprising a silicone polymer and a reticulating agent, chemical reticulation of the fibers and pyrolysis in non-oxidizing atmosphere. Said method is characterized by the use of a polyorganohydrosiloxane as silicone polymer and by a reticulating agent that carries out reticulation by reacting with Si-H bonds of polyorganohydrosiloxane.

Possible Applications

• Structural materials;
• Performance materials;
• High temperature and aggressive environments.

Advantages

• SiOC fibers with low cost production;
• SiOC fibers with high temperature stability;
• SiOC fibers with high elastic modulus;
• Alkali-resistant SiOC fibers;
• Robust process.