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Item Green covalent surface functionalization of carbon nanofillers and hybridization to improve the thermal and electrical properties of RTV SR nanocomposites(Elsevier Ltd, 2025) Chandrashekar, A.; Hegde, M.; Siya; Karthik Reddy, B.; Jineesh, J.A.; Ravichandran, V.; Eswaraiah, E.; Prabhu, T.N.In this work, graphene (GP) and multiwalled carbon nanotubes (MWCNT) are covalently surface functionalized via a green method using clove extract. The clove–modified carbon hybrid silicone rubber (SR) nanocomposites are fabricated by incorporating clove –modified GP (CGP) and MWCNT (CMWCNT) in various weight ratios with a total filler loading of 10 wt%. Our study investigated the effect of green covalent surface modification and the use of hybrid filler on the thermal and electrical properties of the silicone rubber. The nanocomposite with 9:1 hybrid ratio showed the highest thermal conductivity of about 0.406 W m?1 K?1, 103 % enhancement and thermal effusivity of about 766.2 Ws1/2 m?2 K?1, 29.64 % enhancement with respect to pure SR. Thermal management performance was evaluated by applying thermal compounds as thermal interface material on a 1 W light emitting diode (LED) bulb for testing. It was found that during heating, the hybrid composite with 9:1 ratio showed 2.3 °C reduction in the surface temperature of the LED bulb (under ON condition) and reduced the surface temperature by 1.8 ? within 20 s and reached almost room temperature in 100 s (under OFF condition). In addition, nanocomposite with 9:1 hybrid ratio showed excellent thermal stability, enhanced electrical resistivity which presents a promising strategy for designing thermally conductive polymer nanocomposites based thermal interface materials in managing excess heat for thermal management applications. © 2025Item Enhancement of thermal conductivity in silicone rubber nanocomposites via low loading of polydopamine-coated copper nanowires(Elsevier Ltd, 2025) Hegde, M.; Chandrashekar, A.; Reddy B, K.; Jineesh, J.A.; Ajeya, K.P.; Prabhu, T.N.In recent years, thermally conductive polymer nanocomposites have garnered significant interest due to their wide application in the electronic industry. In the present work, we report thermally conductive silicone rubber-based nanocomposites at lower filler loading of polydopamine-coated copper nanowires (PDA@CuNW). First, copper nanowires (CuNW) are synthesized by the liquid phase reduction method and modified with polydopamine (PDA) by in-situ polymerization. The synthesized CuNW and PDA@CuNW are incorporated into Silicone rubber (SR) varying from 1 to 5 wt% via solution casting. The incorporation of 5 wt% PDA@CuNW resulted in a 62 % improvement in the thermal conductivity of SR. In addition, the nanocomposite showed the highest thermal effusivity of 735 Ws1/2m?2 K?1 even at 5 wt% loading. These results can be attributed to the better adhesion of PDA to the SR matrix confirmed by Field Emission-Scanning Electron Microscopy (FE-SEM). Thermogravimetric analysis showed that the modification of copper nanowires improved the thermal stability of SR. The electrical resistivity of SR increased with the addition of PDA@CuNW. The tensile stress-strain studies reveal that the strength of the SR/PDA@CuNW was improved compared to neat SR and SR/CuNW composites. Moreover, the elongation at break reached up to 972 % which is a 395 % improvement with respect to plain SR. In this work, simultaneous improvement in thermal conductivity and electrical resistivity is achieved while preserving the mechanical properties of the SR nanocomposites. Flexible nanocomposites with improved thermal and electrical properties and minimal filler loading have great significance in high-performance thermal management materials. © 2025 Elsevier LtdItem Synergistic enhancement in thermal conductivity of RTV silicone rubber via non-covalently surface-modified graphene and MWCNT hybrid fillers(Springer, 2025) Chandrashekar, A.; Hegde, M.; Siya Shetty; Reddy, B.K.; Jineesh, J.A.; Varrla, E.; Prabhu, T.N.Effective thermal management is critical for advanced electronic devices, yet conventional polymer-based thermal interface materials (TIMs) often exhibit low thermal conductivity, poor filler dispersion, and high interfacial resistance. This study addresses these limitations by enhancing filler–matrix interactions and exploiting synergistic effects between dual-dimensional carbon nanofillers. Graphene (GPs) and multiwalled carbon nanotubes (MWCNTs) were non-covalently surface modified using phenyl glycidyl ether (PGE) via ultrasonication in THF, improving dispersion and compatibility with room temperature vulcanizing silicone rubber (RTV SR). The surface-functionalized fillers (PGE@GP, PGE@MWCNT) were characterized using FTIR, Raman spectroscopy, FESEM, and TGA to confirm successful modification. Composite films were fabricated by incorporating PGE-modified fillers into RTV SR at three different hybrid ratios (PGE@GP:PGE@MWCNT = 9:1, 8:2, and 7:3) with a total filler content of 10 wt%. The composite with a 9:1 ratio achieved the highest thermal conductivity of 0.459 ± 0.001 Wm?1 K?1, representing a 129.5% enhancement over pure RTV SR. The observed 48.06% synergistic improvement highlights the effectiveness of combining dual-dimensional fillers. Additionally, the composite retained electrical insulation, a critical property for TIM applications. Application tests using a 1 W LED bulb demonstrated the composite’s ability to dissipate heat efficiently, confirming its potential as a high performance, electrically insulating thermal interface material for modern electronic systems. © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2025.