Organic-Inorganic Hybrid Aerogel Monoliths – Structural optimization toward improved resilience
by
Kazuki Nakanishi
Institute of Materials and Systems for Sustainability, Nagoya Univ., Japan
Aerogels have a long history and will be familiar to most sol-gel research-ers. Although their peculiar properties such as high visible-light transmit-tance and superb thermal insulation are well recognized, the fragile na-ture arising from their low-density tenuous network is yet to be improved. In 2007, monolithic aerogels that can be fabricated through ambient pres-sure (evaporation) drying were invented using a polymethylsilsesquiox-ane composition where a trifunctional alkoxysilane was used as a precur-sor in the co-presence of surfactant. The resultant aerogel monolith, how-ever, was flexible only against compressive stress, and further improve-ment was required to make them suitable for practical uses such as win-dow applications. Since then, various efforts have been made to improve mechanical strength, especially against bending and tensile stresses. A wide variety of tri- and hexa-functional alkoxysilane precursors were adopted to introduce surface-functionality which allows additional modifi-cation of the nano-sized network, or to enhance flexibility by further re-ducing the effective crosslinking density in the network. “Double cross-links”, comprising the mixed crosslinking of siloxane and hydrocarbon chains, has been shown to be effective in achieving good bending strength and appreciable transmittance/thermal insulation properties .
It is our pleasure to invite you to join the first ISGS eSeminar for 2022 on Tuesday 1 February, which will be delivered by Professor Kazuki Nakanishi.
Professor Nakanishi was the recipient of the ISGS Life Achievement Award in 2021, which will be celebrated at Sol-Gel 2022 in Lyon.
Date: Tuesday 1 February 2022
Format:
- ZOOM (eSeminar link), Meeting ID: 307 291 6432 Passcode: a3*Aqnr@
Time:
- 08:00 – USA, East Coast
- 10:00 – Brazil (São Paulo) and Argentina
- 13:00 – UTC
- 13:00 – UK, Portugal
- 14:00 – Central Europe, Sweden, Norway
- 15:00 – Romania, Israel, Eastern Europe, Ukraine
- 16:00 – Russia (Moscow, St Petersburg)
- 21:00 – China, Singapore, Malaysia
- 22:00 – Japan
- 23:00 – Australia (East Coast)
