Improving Thermal Stability and Hydrophobicity of Rutile-TiO 2 Nanoparticles for Oil-Impregnated Paper Application

Mohammed Mahmood Katun, Rudo Kadzutu-Sithole, Nosipho Moloto, Cuthbert Nyamupangedengu and Chandima Gomes
Additional contact information
Mohammed Mahmood Katun: School of Electrical and Information Engineering (EIE), Faculty of Engineering and the Built Environment(EBE), University of the Witwatersrand, Private Bag 3, Johannesburg 2050, South Africa
Rudo Kadzutu-Sithole: Molecular Science Institute, School of Chemistry, University of the Witwatersrand, Private Bag 3, Johannesburg 2050, South Africa
Nosipho Moloto: Molecular Science Institute, School of Chemistry, University of the Witwatersrand, Private Bag 3, Johannesburg 2050, South Africa
Cuthbert Nyamupangedengu: School of Electrical and Information Engineering (EIE), Faculty of Engineering and the Built Environment(EBE), University of the Witwatersrand, Private Bag 3, Johannesburg 2050, South Africa
Chandima Gomes: School of Electrical and Information Engineering (EIE), Faculty of Engineering and the Built Environment(EBE), University of the Witwatersrand, Private Bag 3, Johannesburg 2050, South Africa

Energies, 2021, vol. 14, issue 23, 1-16

Abstract: Thermal stress and moisture absorption can cause a synergetic negative impact on kraft paper. Among various approaches for improving the dielectric properties of kraft paper, nanotechnology has had promising results. However, the hydrophilicity of most metal oxide nanoparticles renders nanomodified kraft paper more vulnerable to thermal stress and moisture, thereby inducing degradation. In nanomodified kraft paper research, the use of TiO 2 nanoparticles has yielded the most promising results. The major shortfall, however, is the hydrophilicity of TiO 2 . This work investigated surface modifications of rutile-TiO 2 nanoparticles (NPs) for improved hydrophobicity and thermal stability. Rutile-TiO 2 NPs is a nontoxic metal oxide that can withstand high temperature and is stable in chemical reactions. Two cases of surfactants were used—alkyl ketene dimer (AKD) and alkenyl succinic anhydride (ASA). The intention was to increase heat resistance and reduce the surface free energy of the rutile-TiO 2 NPs. The impacts of the surface modifiers on the rutile-TiO 2 NPs were characterised using FT-IR, muffle furnace, analytical weight balance, and TGA. It was discovered that new functional groups were formed on the modified NPs examined through FT-IR spectra. This indicates new chemical bonds, introduced through the surface modification. The unmodified rutile-TiO 2 NPs absorbed moisture, increasing their mass by 3.88%, compared with the modified nanoparticles, which released moisture instead. TGA analysis revealed that AKD- and ASA-modified rutile-TiO 2 needed higher temperatures than the unmodified rutile-TiO 2 to markedly decompose. AKD, however, gave better performance than ASA in that regard. As an example, those modified with 5% AKD sustained a 45% higher temperature than the pure TiO 2 nanoparticles. Furthermore, in both cases of the surfactants, the higher the percent of surfactant content was, the more thermally stable the nanoparticles became. This work demonstrates the possibility of fabricating rutile-TiO 2 NPs to give improved hydrophobicity and thermal stability for possible dielectric applications such as in kraft paper for power transformer insulation.

Keywords: transformer; cellulose; kraft paper; dielectric properties; thermal stability; moisture absorption; hydrophilic; nanoparticles; AKD; ASA; rutile-TiO 2 (search for similar items in EconPapers)
JEL-codes: Q Q0 Q4 Q40 Q41 Q42 Q43 Q47 Q48 Q49 (search for similar items in EconPapers)
Date: 2021
References: View references in EconPapers View complete reference list from CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/1996-1073/14/23/7964/pdf (application/pdf)
https://www.mdpi.com/1996-1073/14/23/7964/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jeners:v:14:y:2021:i:23:p:7964-:d:690501

Access Statistics for this article

Energies is currently edited by Ms. Agatha Cao

More articles in Energies from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().