Characterisation of the pyrolysis process of boron-containing ormosils by FT-IR analysis

✍ Scribed by R. Peña Alonso; F. Rubio; J. Rubio; J.L. Oteo

• Book ID: 104019203
• Publisher: Elsevier Science
• Year: 2004
• Tongue: English
• Weight: 304 KB
• Volume: 71
• Category: Article
• ISSN: 0165-2370
• DOI: 10.1016/j.jaap.2003.11.002

✦ Synopsis

The sol-gel method was used to prepare four different silicon-boron containing gels to obtain monolithic Ormoborosil (organically modified borosilicate) materials. These Ormoborosils were treated under flowing nitrogen at different temperatures from 200 to 1100 • C to produce mixed vitreous oxycarbides of silicon and boron. Fourier transform-infrared spectroscopy (FT-IR) was used to study the structural changes that take place at every studied temperature. Results have shown that boron atoms are bonded preferentially to silicon atoms in the PDMS units. The increase of the boron content in the Ormoborosil network produces a decrease of the mineralisation temperature. Moreover, it has been observed that boron promotes the formation of oxycarbide structures and avoids the formation of a free carbon phase in the oxycarbide network.