The conducting polymer poly(2-(1H-pyrrole-1-yl)ethyl methacrylate (PPEMA) was synthesized by conventional atom transfer radical polymerization for the first time from free as well as surface-bonded alkyl bromide initiator. When grafted from the surface of carbonyl iron (CI) a substantial conducting shell on the magnetic core was obtained. Synthesis of the monomer as well as its polymer was confirmed using proton spectrum nuclear magnetic resonance (1H NMR). Polymers with various molar masses and low dispersity showed the variability of this approach, providing a system with a tailorable structure and brush-like morphology. Successful grafting from the CI surface was elucidate by transmission electron microscopy and Fourier-transform infrared spectroscopy. Very importantly, thanks to the targeted nanometer-scale shell thickness of the PPEMA coating, the magnetization properties of the particles were negligibly affected, as confirmed using vibration sample magnetometry. Smart elastomers (SE) consisting of bare CI or CI grafted with PPEMA chains (CI-PPEMA) and silicone elastomer were prepared and dynamic mechanical properties as well as interference shielding ones were investigated. It was found that short polymer chains grafted to the CI particles exhibited the plasticizing effect, which might be interesting from the magnetorheological point of view, and more interestingly, in comparison to the neat CI-based sample, it provided enhanced electromagnetic shielding of nearly 30 dB in thickness of 500 μm. Thus, SE containing the newly synthesized CI-PPEMA hybrid particles also exhibited considerably enhanced damping factor and proper mechanical performance, which make the material highly promising from various practical application points of view.

Center for Advanced Materials Qatar University Doha P O Box 2713 Qatar

Centre for Advanced Material Application Slovak Academy of Sciences Dubravska Cesta 9 845 11 Bratislava Slovakia

Centre of Polymer Systems University Institute Tomas Bata University in Zlin Trida T Bati 5678 760 01 Zlin Czech Republic

Department of Physics and Materials Engineering Faculty of Technology Tomas Bata University in Zlin Vavřečkova 275 760 01 Zlin Czech Republic

Department of Production Engineering Faculty of Technology Tomas Bata University in Zlin Vavřečkova 275 760 01 Zlin Czech Republic

Polymer Institute Slovak Academy of Sciences Dubravska Cesta 9 845 41 Bratislava Slovakia

See more in PubMed

Ge L., Gong X.L., Wang Y., Xuan S.H. The conductive three dimensional topological structure enhanced magnetorheological elastomer towards a strain sensor. Compos. Sci. Technol. 2016;135:92–99. doi: 10.1016/j.compscitech.2016.09.015. DOI

Yang J., Sun S.S., Du H., Li W.H., Alici G., Deng H.X. A novel magnetorheological elastomer isolator with negative changing stiffness for vibration reduction. Smart Mater. Struct. 2014;23:11. doi: 10.1088/0964-1726/23/10/105023. DOI

Zhao L.J., Yu M., Fu J., Zhu M., Li B.S. A miniature MRE isolator for lateral vibration suppression of bridge monitoring equipment: Design and verification. Smart Mater. Struct. 2017;26:16. doi: 10.1088/1361-665X/aa5d97. DOI

Mietta J.L., Jorge G., Negri R.M. A flexible strain gauge exhibiting reversible piezoresistivity based on an anisotropic magnetorheological polymer. Smart Mater. Struct. 2014;23:12. doi: 10.1088/0964-1726/23/8/085026. DOI

Perales-Martinez I.A., Palacios-Pineda L.M., Lozano-Sanchez L.M., Martinez-Romero O., Puente-Cordova J.G., Elias-Zuniga A. Enhancement of a magnetorheological PDMS elastomer with carbonyl iron particles. Polym. Test. 2017;57:78–86. doi: 10.1016/j.polymertesting.2016.10.029. PubMed DOI PMC

Karl C.W., McIntyre J., Alshuth T., Kluppel M. Magneto-Rheological Elastomers with switchable mechanical Properties. KGK-Kautsch. Gummi Kunstst. 2013;66:46–53.

Lokander M., Stenberg B. Performance of isotropic magnetorheological rubber materials. Polym. Test. 2003;22:245–251. doi: 10.1016/S0142-9418(02)00043-0. DOI

Goshkoderia A., Rudykh S. Stability of magnetoactive composites with periodic microstructures undergoing finite strains in the presence of a magnetic field. Compos. Pt. B-Eng. 2017;128:19–29. doi: 10.1016/j.compositesb.2017.06.014. DOI

Sedlacik M., Mrlik M., Babayan V., Pavlinek V. Magnetorheological elastomers with efficient electromagnetic shielding. Compos. Struct. 2016;135:199–204. doi: 10.1016/j.compstruct.2015.09.037. DOI

Cvek M., Mrlik M., Ilcikova M., Mosnacek J., Munster L., Pavlinek V. Synthesis of Silicone Elastomers Containing Silyl-Based Polymer Grafted Carbonyl Iron Particles: An Efficient Way to Improve Magnetorheological, Damping, and Sensing Performances. Macromolecules. 2017;50:2189–2200. doi: 10.1021/acs.macromol.6b02041. DOI

Sykora R., Babayan V., Usakova M., Kruzelak J., Hudec I. Rubber Composite Materials with the Effects of Electromagnetic Shielding. Polym. Compos. 2016;37:2933–2939. doi: 10.1002/pc.23490. DOI

Darwish M.S.A., Mostafa M.H., Al-Harbi L.M. Polymeric Nanocomposites for Environmental and Industrial Applications. Int. J. Mol. Sci. 2022;23:1023. doi: 10.3390/ijms23031023. PubMed DOI PMC

Darwish M.S.A., Bakry A., Al-Harbi L.M., Khowdiary M.M., El-Henawy A.A., Yoon J. Core/shell PA6 @ Fe3O4 nanofibers: Magnetic and shielding behavior. J. Dispers. Sci. Technol. 2020;41:1711–1719. doi: 10.1080/01932691.2019.1635025. DOI

Joseph N., Sebastian M.T. Electromagnetic interference shielding nature of PVDF-carbonyl iron composites. Mater. Lett. 2013;90:64–67. doi: 10.1016/j.matlet.2012.09.014. DOI

Osicka J., Ilcikova M., Mrlik M., Minarik A., Pavlinek V., Mosnacek J. The Impact of Polymer Grafting from a Graphene Oxide Surface on Its Compatibility with a PDMS Matrix and the Light-Induced Actuation of the Composites. Polymers. 2017;9:264. doi: 10.3390/polym9070264. PubMed DOI PMC

Babayan V., Kazantseva N.E., Moucka R., Stejskal J. Electromagnetic shielding of polypyrrole-sawdust composites: Polypyrrole globules and nanotubes. Cellulose. 2017;24:3445–3451. doi: 10.1007/s10570-017-1357-z. DOI

Kashi S., Gupta R.K., Baum T., Kao N., Bhattacharya S.N. Morphology, electromagnetic properties and electromagnetic interference shielding performance of poly lactide/graphene nanoplatelet nanocomposites. Mater. Des. 2016;95:119–126. doi: 10.1016/j.matdes.2016.01.086. DOI

Moucka R., Mravcakova M., Vilcakova J., Omastova M., Saha P. Electromagnetic absorption efficiency of polypropylene/montmorillonite/polypyrrole nanocomposites. Mater. Des. 2011;32:2006–2011. doi: 10.1016/j.matdes.2010.11.064. DOI

Yuan X.Y., Cheng L.F., Zhang Y.J., Guo S.W., Zhang L.T. Fe-doped SiC/SiO2 composites with ordered inter-filled structure for effective high-temperature microwave attenuation. Mater. Des. 2016;92:563–570. doi: 10.1016/j.matdes.2015.12.090. DOI

Liu X.F., Zhang L.T., Yin X.W., Ye F., Liu Y.S., Cheng L.F. Flexible thin SiC fiber fabrics using carbon nanotube modification for improving electromagnetic shielding properties. Mater. Des. 2016;104:68–75. doi: 10.1016/j.matdes.2016.05.005. DOI

Babayan V., Kazantseva N.E., Sapurina I., Moucka R., Stejskal J., Saha P. Increasing the high-frequency magnetic permeability of MnZn ferrite in polyaniline composites by incorporating silver. J. Magn. Magn. Mater. 2013;333:30–38. doi: 10.1016/j.jmmm.2012.12.045. DOI

Singh A.P., Mishra M., Sambyal P., Gupta B.K., Singh B.P., Chandra A., Dhawan S.K. Encapsulation of γ-Fe2O3 decorated reduced graphene oxide in polyaniline core-shell tubes as an exceptional tracker for electromagnetic environmental pollution. J. Mater. Chem. A. 2014;2:3581–3593. doi: 10.1039/C3TA14212D. DOI

Ohlan A., Singh K., Chandra A., Dhawan S.K. Microwave Absorption Behavior of Core-Shell Structured Poly (3,4-Ethylenedioxy Thiophene)-Barium Ferrite Nanocomposites. ACS Appl. Mater. Interfaces. 2010;2:927–933. doi: 10.1021/am900893d. PubMed DOI

Azadmanjiri J., Hojati-Talemi P., Simon G.P., Suzuki K., Selomulya C. Synthesis and Electromagnetic Interference Shielding Properties of Iron Oxide/Polypyrrole Nanocomposites. Polym. Eng. Sci. 2011;51:247–253. doi: 10.1002/pen.21813. DOI

Vu Q.T., Duong N.T., Duong N.H. Polypyrrole/Al2O3 nanocomposites: Preparation, characterisation and electromagnetic shielding properties. J. Exp. Nanosci. 2009;4:213–219. doi: 10.1080/17458080903115361. DOI

Zhao H., Hou L., Lu Y.X. Electromagnetic interference shielding of layered linen fabric/polypyrrole/nickel (LF/PPy/Ni) composites. Mater. Des. 2016;95:97–106. doi: 10.1016/j.matdes.2016.01.088. DOI

Cagnolati R., Lucchesi M., Rolla P.A., Castelvetro V., Ciardelli F., Colligiani A. DC electrical transport in a new conducting polymer—Oxidized poly(n-vinylpyrrole) Synth. Met. 1992;46:127–131. doi: 10.1016/0379-6779(92)90325-D. DOI

Ruggeri G., Bianchi M., Puncioni G., Ciardelli F. Molecular control of electric conductivity and structural properties of polymers of pyrrole derivatives. Pure Appl. Chem. 1997;69:143–149. doi: 10.1351/pac199769010143. DOI

Radtke M., Ignaszak A. Carbon allotropes grafted with poly(pyrrole) derivatives via living radical polymerizations: Electrochemical analysis of nano-composites for energy storage. RSC Adv. 2017;7:35060–35074. doi: 10.1039/C7RA06981B. DOI

Yoon J.T., Lee S.C., Jeong Y.G. Effects of grafted chain length on mechanical and electrical properties of nanocomposites containing polylactide-grafted carbon nanotubes. Compos. Sci. Technol. 2010;70:776–782. doi: 10.1016/j.compscitech.2010.01.011. DOI

Cheng Q.L., He Y., Pavlinek V., Li C.Z., Saha P. Surfactant-assisted polypyrrole/titanate composite nanofibers: Morphology, structure and electrical properties. Synth. Met. 2008;158:953–957. doi: 10.1016/j.synthmet.2008.06.022. DOI

Cvek M., Mrlik M., Ilcikova M., Mosnacek J., Babayan V., Kucekova Z., Humpolicek P., Pavlinek V. The chemical stability and cytotoxicity of carbonyl iron particles grafted with poly(glycidyl methacrylate) and the magnetorheological activity of their suspensions. RSC Adv. 2015;5:72816–72824. doi: 10.1039/C5RA11968E. DOI

Mrlik M., Pavlinek V. Magnetorheological suspensions based on modified carbonyl iron particles with an extremely thin poly(n-butyl acrylate) layer and their enhanced stability properties. Smart Mater. Struct. 2016;25:085011. doi: 10.1088/0964-1726/25/8/085011. DOI

Cvek M., Kollar J., Mrlik M., Masar M., Suly P., Urbanek M., Mosnacek J. Surface-initiated mechano-ATRP as a convenient tool for tuning of bidisperse magnetorheological suspensions toward extreme kinetic stability. Polym. Chem. 2021;12:5093–5105. doi: 10.1039/D1PY00930C. DOI

Mrlik M., Ilcikova M., Pavlinek V., Mosnacek J., Peer P., Filip P. Improved thermooxidation and sedimentation stability of covalently-coated carbonyl iron particles with cholesteryl groups and their influence on magnetorheology. J. Colloid Interface Sci. 2013;396:146–151. doi: 10.1016/j.jcis.2013.01.027. PubMed DOI

Mrlik M., Ilcikova M., Cvek M., Pavlinek V., Zahoranova A., Kronekova Z., Kasak P. Carbonyl iron coated with a sulfobetaine moiety as a biocompatible system and the magnetorheological performance of its silicone oil suspensions. RSC Adv. 2016;6:32823–32830. doi: 10.1039/C6RA03919G. DOI

Stejskal J., Omastova M., Fedorova S., Prokes J., Trchova M. Polyaniline and polypyrrole prepared in the presence of surfactants: A comparative conductivity study. Polymer. 2003;44:1353–1358. doi: 10.1016/S0032-3861(02)00906-0. DOI

Cvek M., Mrlik M., Sevcik J., Sedlacik M. Tailoring Performance, Damping, and Surface Properties of Magnetorheological Elastomers via Particle-Grafting Technology. Polymers. 2018;10:1411. doi: 10.3390/polym10121411. PubMed DOI PMC

Ilcikova M., Mrlik M., Sedlacek T., Doroshenko M., Koynov K., Danko M., Mosnacek J. Tailoring of viscoelastic properties and light-induced actuation performance of triblock copolymer composites through surface modification of carbon nanotubes. Polymer. 2015;72:368–377. doi: 10.1016/j.polymer.2015.03.060. DOI

Ilcikova M., Mrlik M., Sedlacek T., Slouf M., Zhigunov A., Koynov K., Mosnacek J. Synthesis of Photoactuating Acrylic Thermoplastic Elastomers Containing Diblock Copolymer-Grafted Carbon Nanotubes. ACS Macro Lett. 2014;3:999–1003. doi: 10.1021/mz500444m. PubMed DOI

Possinger T., Bolzmacher C., Bodelot L., Triantafyllidis N. Interfacial adhesion between the iron fillers and the silicone matrix in magneto-rheological elastomers at high deformations. In: Schmid U., Aldavero J., Leester Schaedel M., editors. Smart Sensors, Actuators, and Mems Vi. Volume 8763 SPIE-Int. Soc. Optical Engineering; Bellingham, WA, USA: 2013.

Yao F., Wu Q.L., Lei Y., Xu Y.J. Rice straw fiber-reinforced high-density polyethylene composite: Effect of fiber type and loading. Ind. Crops Prod. 2008;28:63–72. doi: 10.1016/j.indcrop.2008.01.007. DOI

Kirchberg S., Ziegmann G. Thermogravimetry and Dynamic Mechanical Analysis of Iron Silicon Particle filled Polypropylene. J. Compos. Mater. 2009;43:1323–1334. doi: 10.1177/0021998308105288. DOI

Lakshmi N.V., Tambe P., Panda B. Surface modified iron oxide (Fe3O4) nanosheets reinforced PVDF nanocomposites: Influence on morphology, thermal and magnetic properties. Plast. Rubber Compos. 2022;51:205–216. doi: 10.1080/14658011.2021.1966248. DOI

Anju R.S., Yadav R.S., Potschke P., Pionteck J., Krause B., Kuritka I., Vilcakova J., Skoda D., Urbanek P., Machovsky M., et al. CuxCo1-xFe2O4 (x = 0.33, 0.67, 1) Spinel Ferrite Nanoparticles Based Thermoplastic Polyurethane Nanocomposites with Reduced Graphene Oxide for Highly Efficient Electromagnetic Interference Shielding. Int. J. Mol. Sci. 2022;23:2610. doi: 10.3390/ijms23052610. PubMed DOI PMC

Gupta S., Chang C., Lai C.H., Tai N.H. Hybrid composite mats composed of amorphous carbon, zinc oxide nanorods and nickel zinc ferrite for tunable electromagnetic interference shielding. Compos. Pt. B-Eng. 2019;164:447–457. doi: 10.1016/j.compositesb.2019.01.060. DOI

Kumar A., Singh A.K., Tomar M., Gupta V., Kumar P., Singh K. Electromagnetic interference shielding performance of lightweight NiFe2O4/rGO nanocomposite in X- band frequency range. Ceram. Int. 2020;46:15473–15481. doi: 10.1016/j.ceramint.2020.03.092. DOI

Li X.H., Shu R.W., Wu Y., Zhang J.B., Wan Z.L. Fabrication of nitrogen-doped reduced graphene oxide/cobalt ferrite hybrid nanocomposites as broadband electromagnetic wave absorbers in both X and Ku bands. Synth. Met. 2021;271:116621. doi: 10.1016/j.synthmet.2020.116621. DOI

Lopatin A.V., Kazantsev Y.N., Kazantseva N.E., Apletalin V.N., Mal’tsev V.P., Shatrov A.D., Saha P. Radio absorbers based on magnetic polymer composites and frequency-selective surfaces. J. Commun. Technol. Electron. 2008;53:1114–1122. doi: 10.1134/S1064226908090131. DOI

In-Situ Coating of Iron with a Conducting Polymer, Polypyrrole, as a Promise for Corrosion Protection