Energy harvesting by dielectric elastomer generators Project Number: IZERZO_142215/1; 10/RO-CH/RSRP/01.01.2013 Partners: EMPA- Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Functional Polymers, Dübendorf, Switzerland ICMPP- ”Petru Poni” Institute of Macromolecular Chemistry, Iasi, Romania

Summary The search for new reliable green sources of energy increased significantly in the last years. Nature offers a number of sources of “unlimited” energy, ocean wave’s energy being one of them. Dielectric elastomer generators are a relatively new technology that can convert mechanical energy (e.g. wave energy) into more useful electrical energy. It is the aim of this project to develop new materials for Dielectric elastomer generators. New silicone based elastomeric materials with increased permittivity, low dielectric losses, low conductivity, and good mechanical properties will be prepared. In order to increase permittivity, polar groups will be attached to the silicone chains. Copolymers containing different amounts of dipoles at random position on the chain as well as copolymers where the position of the dipole is precisely controlled will be made. The newly prepared materials will be investigated regarding their mechanical and electrical properties as well as regarding their feasibility to convert mechanical energy into electrical energy. At the end of the project, not only should a good material for dielectric elastomer generators be achieved but also the understanding on structure property relationship would be greatly improved.

Keywords: permittivity, polar silicones synthesis, elastomers, actuators, dielectric elastomer generators Start/End: 01.01.2013 - 31.12.2015 Principal investigators: Dr. Dorina Maria Opris –EMPA Dr. Carmen Racles -ICMPP

Approved budget in CHF SNSF contribution UEFISCDI CH team RO team Total 178516 141310 56440 376266

RESULTS Patent: High permittivity polymers based on functionalized silicones, D. Opris, S. Dunki, C. Racles, A. Bele , M. Cazacu - Brevet international nr. WO 2015/135086 A1 Publications: 1) „Synthesis and characterization of silicones containing cyanopropyl groups and their use in dielectric elastomer actuators”, C. Racles, M. Cazacu, B. Fischer, D.M. Opris, Smart Mater. Struct. 2013, 22, 104004. 2) „Chemical modification of polysiloxanes with polar pendant groups by co hydrosilylation”, C. Racles, M. Alexandru, A. Bele, V. Musteata, M. Cazacu, D.M. Opris, RSC Adv., 2014, 4(71), 37620-37628. 3) „Tailoring the dielectric properties of silicones by chemical modification”, C. Racles, M. Alexandru, A. Bele, V. Musteata, M. Cazacu, D. Opris, in: "Research Developments in Polymer Science" Volume 12(2014), p. 17-36, Editor: S.G. Pandalai; ISBN: 978-81-7895-611-4, Research Signpost, Transworld Research Network. 4) “Polar–nonpolar interconnected elastic networks with increased permittivity and high breakdown fields for dielectric elastomer transducers”, C. Racles, A. Bele, M. Dascalu, V.E. Musteata, C.D. Varganici, D. Ionita, S. Vlad, M. Cazacu, S.J. Dunki, D.M. Opris, RSC Adv., 2015, 5, 58428- 58438.

5) “Fine-tuning of the dielectric properties of polysiloxanes by chemical modification” S.J. Dünki, M. Tress, F. Kremer, S.Y. Ko, F.A. Nüesch, C.D. Varganici, C. Racles, D.M. Opris, RSC Adv. 2015, 5, 50054-50062. 6) “Full silicone interpenetrating bi-networks with different organic groups attached to the silicon atoms” C. Tugui, M. Cazacu, L. Sacarescu, A. Bele, G. Stiubianu, C. Ursu, C. Racles, Polymer, 2015, 77, 312-322. 7) “Tuning the electromechanical properties of silicones by crosslinking agent” A. Bele, M. Cazacu, C. Racles, D.M. Opris, G. Stiubianu, D. Ovezea, M. Ignat,, Adv. Eng. Mater, 2015, 17(9), 1302–1312. 8) “Highly stretchable composites from pdms and polyazomethine fine particles” C. Racles, V.E. Musteata, A. Bele, M. Alexandru, C. Tugui, A. Matricala, RSC Adv., 2015, 5, 102599- 102609. 9) “Dielectric Materials, Design and Realization”, D.M. Opris, J.E.Q. Quinsaat, S. Dunki, Y.S. Ko, M. Alexandru, C. Racles F.A. Nuesch in: ELECTROACTIVE POLYMER ACTUATORS AND DEVICES (EAPAD) 2015, Proceedings of SPIE, Edited by BarCohen, Y, Volume: 9430, Article Number: 94300A, DOI: 10.1117/12.2086134

Communications and posters:  1. D.M. Opris, S. Grimm, F. Nüesch, M. Molberg, G. Kovacs, C. Racles, M. Cazacu, J. Quinsaat, H. Hofmann, "Self-reparable Dielectric Elastomer Actuators"; Makromolekulares Kolloquium Freiburg, February 23 - 25, 2012, Freiburg, Germany. (oral communication) 2. D.M. Opris, S. Dünki, F. Nüesch, J.E.Q. Quinsaat, Y. Song Ko, S. Michel, C. Racles, M. Cazacu, "Dielectric elastomers put to work", SCS Fall Meeting 2013, September 6, 2013, Lausanne, Switzerland. (oral communication) 3. D.M. Opris, J.E.Q. Quinsaat, Fr. Nüesch, H. Hofmann, C. Racles, M. Cazacu, "Dielectric elastomer actuators", Makromolekulares Kolloquium Freiburg, 24-26 February, 2013, Freiburg, Germany. (poster) C. Racles, M. Cazacu, D. Opris, “Silicone elastomers for actuation” EuroEAP 2011: First international conference on Electromechanically Active Polymer (EAP) transducers & artificial muscles, Pisa, 8-9 June 2011. (poster) C. Racles, M. Cazacu, B. Fischer, D.M. Opris, “Synthesis and characterization of silicones containing cyanopropyl groups and their use in dielectric elastomer actuators”; EuroEAP 2013: International conference on Electromechanically Active Polymer (EAP) transducers & artificial muscles, Dübendorf, 25-26 June 2013. (poster)

6. C. Racles, M. Cazacu, M. Alexandru, A. Bele, V. Musteata, D 6. C. Racles, M. Cazacu, M. Alexandru, A. Bele, V. Musteata, D. Ionita, S. Vlad, C. Varganici, F. Doroftei, “Polimeri siliconici cu grupe polare pentru actuatie”, Zile Academice Iesene, 2- 5 oct. 2013, Iasi. (poster) 7. C. Racles, M. Alexandru, V. Musteata, A. Bele, M. Cazacu, “Tailoring the dielectric properties of silicones by chemical modification”, The 13th International Balkan Workshop on Applied Physics, Constanta, 4-6 July 2013. (poster) 8. C. Racles, M. Alexandru, A. Bele, V. Musteata, M. Cazacu, S. Dunki, D.M. Opris, “New insights into tailoring dielectric properties of silicones by chemical modification”, EuroEAP 2014, Linköping, Sweden, 10-11 June 2014. (poster) 9. A. Bele, M. Cazacu, M. Alexandru, V. Musteata, D.M. Opris, C. Racles, “A dual strategy for improving the electromechanical properties of silicones”, EuroEAP 2014, Linköping, Sweden, 10-11 June 2014. (poster) C. Racles, M. Cazacu, M. Alexandru, A. Bele, V. Musteata, F. Doroftei, “Composites from incompatible polymer pairs: silicone elastomers as disperse phase or matrix”, ICCE-22, Malta, July 13-19, 2014. (oral communication) 11. V.E. Musteata, C. Racles, M. Cazacu, M. Alexandru, A. Bele, D.M. Opris, “Polysiloxanes for dielectric actuators and their molecular dynamics, 8th International Symposium “Molecular Order and Mobility in Polymer Systems”, St. Petersburg, June 2-6, 2014. (poster)

12. S. Dünki, M. Alexandru, A. Bele, M. Cazacu, F. Nüesch, D. Opris, C 12. S. Dünki, M. Alexandru, A. Bele, M. Cazacu, F. Nüesch, D. Opris, C. Racles, “Influence of Polar Groups on the Dielectric Constant of Silicones”, Macromolecular Colloquium, 26- 28.02.2014, Freiburg, Germany. (poster) 13. C. Racles, M. Alexandru, M. Cazacu, A. Bele, S. Dünki, D.M. Opris, “Polysiloxanes with g- cyanopropyl groups: considerations on(co)-hydrosilylation reactions and applications for dielectric elastomer transducers”, PolyColl 2014 Annual Meeting of the Division of Polymers, Colloids and Interfaces, 20 June 2014, Dubendorf, Switzerland. (poster) 14. M. Dascalu, A. Bele, V.E. Musteata, M. Cazacu, D. M. Opris, C. Racles, “Elastic silicone networks with increased permittivity and high breakdown fields for dielectric elastomer transducers”, The 3nd CEEPN Workshop on Polymer Science, “Petru Poni” Institute of Macromolecular Chemistry, September 23-26, 2015, Iasi (oral communication) 15. C. Racles, M. Dascalu, A. Bele, V. Musteata, M. Cazacu, D.M. Opris, “Polar silicones for electro-mechanical transduction”, Seventh Cristofor I. Simionescu Symposium, 4-6 iunie 2015, Iasi (poster) 16. M. Dascalu, A. Bele, V. Musteata, M. Cazacu, Si. Duenki, D. Opris, C. Racles, “Polar-nonpolar interconnected elastic networks with increased permittivity and high breakdown fields for dielectric elastomer transducers”, 5th International conference on Electromechanically Active Polymer (EAP) transducers & artificial muscles, June 9-10, 2015, Tallinn, Estonia (poster)

17. M. Dascalu, A. Bele, M. Cazacu, D. Opris, C 17. M. Dascalu, A. Bele, M. Cazacu, D. Opris, C. Racles, “Transduction performance of polar-nonpolar silicone materials: interconnection versus blending”, 5th international conference on Electromechanically Active Polymer (EAP) transducers & artificial muscles, June 9-10, 2015, Tallinn, Estonia (poster) 18. A. Bele, C. Racles, M. Dascalu, E. Perju, D. Opris, M. Cazacu, “Dielectric silicone elastomers filled with in situ generated polar silsesquioxane”, 5th International conference on Electromechanically Active Polymer (EAP) transducers & artificial muscles, June 9-10, 2015, Tallinn, Estonia (poster)

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