[article]
Titre : |
Microwave absorbing coating based on epoxy/ionic liquid system : A review |
Type de document : |
texte imprimé |
Auteurs : |
Uday D. Patil, Auteur |
Année de publication : |
2023 |
Article en page(s) : |
p. 64-74 |
Note générale : |
Bibliogr. |
Langues : |
Anglais (eng) |
Catégories : |
Diélectriques Epoxydes Liquides ioniques Micro-ondes -- Absorption Réticulants Revêtements organiques
|
Index. décimale : |
667.9 Revêtements et enduits |
Résumé : |
This is the review on Microwave absorbing coating based on Epoxy/lonic Liquids (ILs) which is used alone and in combination with Hardeners MTHPA and MCDEA. lonic Liquid is used as a curative for Epoxy resin in this review paper but it has many more advantageous benefits over conventional curing systems e.g. used in Solvent recovery, as a Lubricant, as a Plasticizer, and as a Catalyst. Microwave radiation is a more crucial topic for today's life and getting rid of it is a challenge. So here cornes a solution lonic Liquid-based Microwave radiation absorbing coating. lonic Liquid (IL) is changing the future of the epoxy system and is also based on green chemistry which can be helpful to reduce environmental stress. Neat bmim.BF4 was able to cure epoxy resin, giving rise to networks with outstanding thermal stability compared with the systems cured with an anhydride or aromatic amine. The epoxy networks were cured with bmim.BF4 atone or in combination with an anhydride or aromatic amine were transparent and presented considerable microwave absorbing properties in the X- band frequency range (8-12 GHz), being the best performance observed for the systems cured with bmim.BF4/anhydride curing system, with reflection loss value around —16 dB at 11.3 Ghz.
In another part, the microwave-absorbing properties of 1-ethyl-3-methylimidazolium and 1- buty/-3 methylimidazolium ([E and BMlm] +- based) room-temperature ionic liquids (ILs) with different anions were systematically investigated by Fulong Yang et al. measuring dielectric properties in the 1-14 GHz microwave-frequency range. The results showed that the real part of permittivity' values decreased from 13 to 4 and the values of loss tangent decreased from 5.91 to 0.24, meaning that ILs displayed high dielectric-loss characteristics at microwave-frequency ranges. Furthermore, it was found that the conductivity loss was dominant for dielectric loss in the low-frequency band, and the polarization loss played a major role in high-frequency bands. For the same anion ILs with different cations, the permittivity became higher as the length of the alkyl chain decreased. The absorption properties of [E and BMlm] +- based ILs could be obtained based on their dielectric properties and found the ILs absorption bands were mainly concentrated in the C band and X band. It was noted that the maximum reflection loss (RL) of [BMIrn][NTf2] with a thickness of 4 mm reached — 27.6 dB at 8.73 GHz, and the bandwidth of an RL less than 10 dB could be up to 4.3 GHz. The absorption peak frequency of the ILs gradually shifted to lower frequencies with increasing temperature and coating thickness, which might be caused by the change in impedance matching. |
Note de contenu : |
- Types of ionic liquids
- Application of ionic liquid : Ionic liquids as catalytic agents - Ionic liquids as ionic conducting agents
- Ionic liquids as lubricants
- Ionic liquid with microwave absorbing coating
- Materials
- Used
- Dielectric properties
- Microwave-absorption properties
- Table 1 : General overview of ionic liquid influence on epoxy resins
- Table 2 : Change in maximum reflection losses values of RLM (dB) and peak frequency (FP of [BMIm] +- based ILs with different temperatures
- Table 3 : Details of maximum reflection losses values of RLM (dB) and peak frequency (FP) of [BMlm] +- based ILs |
En ligne : |
https://drive.google.com/file/d/1CaE6b9g0EOPyRpiHoe_XSWnbBBjCgu3K/view?usp=drive [...] |
Format de la ressource électronique : |
Pdf |
Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=40398 |
in PAINTINDIA > Vol. LXXIII, N° 9 (09/2023) . - p. 64-74
[article]
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