Studies on evolution of nano SiC ceramics from allylborosiloxane. Issue 1 (January 2016)

• Record Type: Journal Article
• Authors: Sasikala, T.S.; Thomas, Deepthi; Devapal, Deepa
• Is Part Of: Ceramics international. Volume 42:Issue 1:Part B(2016)
• Page Start: 1618
• Page End: 1626
• Publication Date: 2016-01
• Subjects: Spectroscopy B -- Sintering A -- X-ray methods B -- Ceramics; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2015.09.113
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: Allylborosiloxane preceramic oligomers with ceramic residue in the range 75–84% (at 900 °C) were synthesized through the condensation of phenyl boronic acid (PBA) with allyltriethoxysilane (ALTEOS) in three different monomer feed ratios. The oligomers were characterized by GPC, IR, viscosity, TGA and TG–MS techniques. There is an increase in ceramic residue with increase in ALTEOS and maximum residue of 84% was obtained for the oligomer synthesized from PBA and ALTEOS in 1:2 ratio. The oligomers were pyrolysed at 900 °C followed by heat treatment at 1500 °C and 1650 °C in inert atmosphere and were characterized by spectroscopic techniques. Even though SiC formation is observed at 1500 °C, conversion of SiBOC/SiOC to SiC is not complete at 1500 °C and the presence of silica and carbon phases are found in the ceramics. Spectral studies reveals that β-SiC with trace amount of α-SiC is formed when oligomers are heated at 1650 °C in argon atmosphere.