Improving the thermal stability and dielectric properties of epoxy/phenolic resin type (novolac) composites by incorporating carbon nanofibers (CNFs)

Elsammani Ali Shokralla

doi:10.46481/jnsps.2025.2154

Authors

Elsammani Ali Shokralla
[email protected]
Department of Physics, Faculty of Science, Al-Baha University, Saudi Arabia, Aqiq, Saudi Arabia.

Keywords:

Dielectric Constant, Dielectric Relaxation, Dissipation Factor, Relaxation Time, Thermal stability.

Abstract

This study aims to enhance the thermal stability and dielectric properties of an epoxy/phenolic resin-type novolac blend by incorporating carbon nanofibers (CNFs). The EP/novolac-CNF composite was created by dispersing a 10% weight fraction of CNFs into the EP/novolac blend. Various analyses were conducted to assess the improvements brought by the addition of CNFs. Differential Thermal Analysis (DTA) and Dielectric Measurements (DM) were employed to determine the T_gvalues. Thermogravimetric Analysis (TG) and Differential Thermogravimetric Analysis (DTG) were used to evaluate the thermal stability. Results indicated that the inclusion of carbon nanofibers enhanced the thermal stability of the composite, as evidenced by the increased char yield at temperatures exceeding 700 ^oC, reaching 27.08% compared to 8.4% for the EP/novolac blend. Dielectric measurements were conducted across a frequency range of 10²-10⁷Hz and a temperature range of 293-463 K. The results revealed a wide dielectric dispersion in all samples, indicating the presence of Debye relaxation and a broad distribution of relaxation times. Eyring’s relaxation rate equation was applied to determine the thermodynamic parameters, such as the Gibbs free energy of activation (\Delta G) and entropy (\Delta S). The results indicated strong intermolecular interactions in all tested samples. The incorporation of carbon nanofibers into the EP/novolac blend led to improvements in thermal stability and dielectric properties. The analysis of various parameters suggests enhanced performance and potential applications of the EP/novolac-CNF composite in relevant fields.

Dimensions

REFERENCES

G. M. Luz, L. G. Mano, “Mineralized structures in nature: Examples and inspirations for the design of new composite materials and biomaterials”, Composites Science and Technology 70 (2010) 1777. .http://doi.org/10.3390/ma6062543.

K. Song, Y. Zhang, J. Meng, E. Green, N. Tajaddod, H. Li & M. Minus, “Structural polymer-based carbon nanotube composite fibers understanding the processing structure performance relationship”, Materials 6 (2013) 2543. http://doi.org/10.3390/ma6062543.

S. Belloa, J. Agunsoyeb, S. Hassana, M. Zebase, I.Kana & M. Raheem, “Epoxy resin based composites, mechanical and Tribological properties: A review”, Tribology in Industry 37 (2015) 500. https://doi.org/10.1007/978-981-15-6267-916.

N. Phong, M. Gabr, L. Anh, V. Duc, A. Betti, K. Okubo, B. Chuong & T. Fujii, “Improved fracture toughness and fatigue life of carbon fiber reinforced epoxy composite due incorporation of rubber nanoparticles”, Journal of Material Science 48 (2013) 6039. https://doi.org/10.1007/s10853-013-7400-z.

S. Rathinavel, V. Priyadharshini & D. Panda, “A review on carbon nanotube: An overview of synthesis, properties, functionalization, characterization, and the application”, Materials Science and Engineering B 268 (2021) 115095. https://doi.org/10.1016/j.mseb.2021.115095.

M. Kooti. A. Sedeh, K. Gheisari & A. Figuerola, “Synthesis, characterization, and performance of nanocomposites containing reduced graphene oxide, polyaniline, and cobalt ferrite”, Physica B: Condensed Matter 612 (2021) 412974. https://doi.org/10.1016/j.physb.2021.412974.

M. Shettar, C. Kowshik, M. Manjunath & P. Hiremath, “Experimental investigation on mechanical and wear properties of nanoclay epoxy composites”, Journal of Materials Research and Technology 9 (2020) 9108. https://doi.org/10.1016/j.jmrt.2020.06.058

M. Jawaid, S. Chee, M. Asim, N. Saba & S. Kalia, “Sustainable kenaf/bamboo fibers/clay hybrid nanocomposites: Properties, environmental aspects and applications”, Journal of Cleaner Production 330 (2022) 129938. https://doi.org/10.1016/j.jclepro.2021.12993.

S. Moharana & B. Sahu, Synthesis and properties of epoxy-based composites, IntechOpen Limited, London, United Kingdom, (2022) pp. 1-28. https://doi.org/10.5772/intechopen.104119.

Y. Baghdadi, L. Youssef, K. Bouhadir, M. Harb, S. Mustapha, D. Patra & A. Riza, “Thermal and mechanical properties of epoxy resin reinforced with modified iron oxide nanoparticles”, Journal of Applied Polymer Science 138 (2021) 50533. https://doi.org/10.1002/app.49330.

M. Seong & D. Kim, ”Effects of facile amine-functionalization on the physical properties of epoxy/graphene Nano platelets nanocomposites”, Journal of Applied Polymer Science 132 (2015) 42269.https://doi.org/10.1002/app.42269.

D. Yadav, F. Amini & A. Ehrmann, “Recent advances in carbon nanofibers and their applications: a review”, European Polymer Journal 138 (2020) 109963. https://doi.org/10.1016/j.eurpolymj.2020.109963.

X. Yang, Y. Chen, C. Zhang, G. Duan & S. Jiang, “Electrospun carbon nanofibers and their reinforced composites: Preparation, modification, applications, and perspectives”, Composites Part B Engineering 249 (2023) 110386. https://doi.org/10.1016/j.compositesb.2022.110386.

M. Hao, X. Qian, Y. Zhang, J. Yang, C. Li, H. Gong, X. Wang, P. Wang, L. Liu & Y. Huang, “Thermal conductivity enhancement of carbon fiber/epoxy composites via constructing three-dimensionally aligned hybrid thermal conductive structures on fiber surfaces”, Composites Science and Technology 231 (2023) 109800.https://doi.org/10.1016/j.compscitech.2022.109800.

D. Jeon, S. H. Kim, W. Choi & C. Byon, “An experimental study on the thermal performance of cellulose-graphene-based thermal interface materials”, International Journal Heat Mass Transfer 132 (2019) 944. https://doi.org/10.14447/jnmes.v17i2.433.

J. Khan., S. Momin, & M. Mariatti, “Review on advanced carbon-based thermal interface materials for electronic devices”, Carbon 168 (2020) 65. https://doi.org/10.1016/j.carbon.2020.06.012.

N. Greef, L. Zhang, A. Magrez, L. Forro, J. Locquet, L. Verpoest & J. Seo, “Direct growth of carbon nanotubes on carbon fibers: Effect of the CVD parameters on the degradation of mechanical properties of carbon fibers”, Diamond Related Mater 51 (2015) 39. https://doi.org/10.1016/j.diamond.2014.11.002

J. Costard, M. Ender, M. Weiss, & E. Tiffee, “Three-electrode setups for lithium-ion batteries II. experimental study of different reference electrode designs and their implications for half-cell impedance spectra”, Journal of The Electrochemical Society 164 (2017) 80. http://doi.org/10.1149/2.0241702jes.

W. Hong & N. Tai, “Investigations on the thermal conductivity of composite reinforced with carbon nanotubes”. Diamond Related Matter 17 (2008) 1577. https://doi.org/10.1016/j.diamond.2008.03.037.

A. Shimamura, Y. Hotta, H.i Hyuga, M. Hotta & K. Hirao,“Improving the thermal conductivity of epoxy composites using a combustionsynthesized -Si3N4 filler with randomly oriented grains”, Scientific Reports 10 (2020) 14926.https://doi.org/10.1038/s41598-020-71745-w.

M. Haruki, “Thermal Conductivity for Polymer Composite Materials”, Journal of Chemical Engineering of Japan 54 (2021) 186. https://doi.org/ 10.1252/jcej.20we136.

S. A. Shokralla & N. S. Al-Muaikel, “Thermal properties of Epoxy (DGEBA) /Phenolic resin (Novolac) Blends”, The Arabian Journal for Science and Engineering B 35 (2010) 7.https://www.researchgate.net/profile/Nayef-Al-Muaikel/publication/267564344_Thermal_properties_of_epoxy_DGEBAphenolic_resin_NOVOLAC_blends/links/5517bc820cf2f7d80a3b8fa6/Thermal-properties-of-epoxy-DGEBA-phenolic-resin-NOVOLAC-blends.pdf

M.Lila, G.Saini, M. Kannan & I. Singh, “Effect of Fiber Type on Thermal and Mechanical Behavior of Epoxy Based Composites”, Fibers and Polymers 18 (2017) 806. https://doi.org/10.1007/s12221-017-1147-0.

V. Chinnasamy, S.Subramani , S. Palaniappan, B. Mylsamy & K. Aruchamy, “Characterization on thermal properties of glass fiber and kevlar fiber with modified epoxy hybrid composites”, Journal of Mater Research Technology 9 (2020) 3158.https://doi.org/10.1016/j.jmrt.2020. 01.061.

J. Zhang, M. Ma, Y. Bi , Z. Liao, Y. Ma, W. Huang, P. Lyu & C. Feng, “A review of epoxy-based composite materials: Synthesis, structure and application for electromagnetic wave absorption”, Journal of Alloys and Compounds 922 20 (2022) 166096. https://doi.org/10.1016/j.jallcom. 2022.166096.

E. A. Shokralla, “Dielectric relaxation, electric conductivity and thermodynamic studies on epoxy polyurethane blend and their composites”, International journal of Materials Science and Applications 13 (2024) 6.https://doi.org/10.11648/ijmsa.20241301.12.

Z. Wang, M. Yang, Y. Cheng, J. Liu, G. Wu & H. Wu, “Dielectric properties and thermal conductivity of epoxy composites using quantum-sized silver decorated core/shell structured alumina/polydopamine”, Composites Part A: Applied Science and Manufacturing 118 (2019) 302. https://doi.org/10.1016/j.compositesa.2018.12.022.

Z. M. Elimat, M. S. Hamideen, K. I. Schulte, H. Wittich, A. de la Vega, M. Wichmann & S. Buschhorn, “Dielectric properties of epoxy/short carbon fiber composites”, Journal of Materials Science 45 (2010) 5196.https://doi.org/10.1007/s10853-010-4557-6.

A. A. Kareem, “Enhanced thermal and electrical properties of epoxy/carbon fiber silicon carbide composites”, Advanced Composites Letter 19 (2020) 1. https://doi.org/10.1177/2633366X1989459.

H. Prashanth, P. Shanmugasundram, E. Jayamani & K. Heng, “A comprehensive review on dielectric composites: Classification of dielectric composites”, Renewable and Sustainable Energy Reviews 157 (2022) 112075. https://doi.org/10.1016/j.rser.2022.112075.

V. Kumar , S. Ramakrishna , S. Rajendran & S. Surendran, “Enhancing the material properties of carbon fiber epoxy composite by incorporating electrospun polyacrylonitrile nanofibers”, Materials Today Proceedings 67 (2022) 1. https://doi.org/10.1016/j.matpr.2022.04.818.