Polydimethylsiloxane coated carbon fibres for the production of carbon-fibre reinforced carbon

✍ Scribed by K.J. Hüttinger; G. Krekel

• Publisher: Elsevier Science
• Year: 1991
• Tongue: English
• Weight: 750 KB
• Volume: 29
• Category: Article
• ISSN: 0008-6223
• DOI: 10.1016/0008-6223(91)90022-b

✦ Synopsis

HT-fibres (Grafil XAS12K) were coated with thin layers of polydimethylsiloxane in order to prevent or diminish the adhesion of the phenolic resin to the fibre surfaces. The physical and chemical changes of the polydimethylsiloxane layer at various stages of curing and thermal treatment were studied using contact angle measurements, scanning electron microscopy, infrared spectroscopy, and ESCA. It is shown by the various methods that the adhesion can, in fact, be prevented up to 600°C or 700°C. Beyond this temperature the polydimethylsiloxane layer is decomposed to silica, which effects a very strong adhesion of the carbonized matrix. This is reflected by an interlaminar shear strength that is 60% higher than that of composites with non-coated fibres.

Kev Words-Carbon-fibre reinforced carbon, adhesion, polydimethylsiloxane coating, interlaminar she"ar strength.