Self-Healing Polymers

The current trend in the development of self-healing materials  focuses on polymeric materials, including thermoplasts, thermosets and elastomers, although concepts have been developed for metallic alloys, ceramics as well as their composites. A broad variety of different self-healing approaches have been published over the last years, primarily concerning four distinctly different approaches: (a) the microcapsule approach, (b) supramolecular self-assembly (c) ionomeric systems and (d) reversible covalent bond formation

In either case, a healable polymer must possess the ability to form multiple new bonding interactions in and around the damage-zone. Elastomeric materials exhibit enormous extensibility up to several hundred percent, and have a wide range of commercial applications. The development of technically relevant elastomers with the ability of intrinsic and repeatable self-repairing is one of the most popular desires of modern material sciences. Dealing with this challenge, we are part of the project: „Design and Generic Principles of Self-healing Materials” (SPP 1568) founded by the German Science Foundation (DFG).

Activation of Self-Healing Processes in Ionomeric Elastomers by Local Heating (DFG-SPP 1568typo3/#_msocom_1 )

An elegant way to restore the materials structural integrity proceeds by the selective heating of damaged areas to support polymeric chain movement, diffusion and particularly the new or re-formation of non-covalent chemical bonds. Especially reversible ionic interactions in ionomers along with clustering and the formation of multiplets are favoured. Goal of the present proposal will be the development and testing of elastomeric polymers modified with "nano-hotspots" that can selectively be heated.  

1) "New attitude in polymers - self-healing", A. Nellesen, A. M. Schmidt, J. Bertling, M. von Tapavicza in: Design and nature V. Comparing design in nature with science and engineering, C. A. Brebbia (ed,), WIT press Southhampton, ISBN 978-1-84565-454-3,  (2010).
2) "Self-Healing in plants as a model for self-repairing elastomer materials", A. Nellesen, M. v. Tapavicza, J. Betling, A. M. Schmidt, G. Bauer, T. Speck, Polym. Renew. Resources 2(4), 149-156, (2011).
3) "Biomimetik Self-Healing Elastomers", A. Nellesen, M. v. Tapavicza, J. Bertling, A. M. Schmidt, G. Bauer, T. Speck, GAK Gummi Fasern Kunststoffe 64(8), 472-475, (2011).
4) "Self-Healing in plants as a model for self-repairing elastomer materials", A. Nellesen, M. v. Tapavicza, J. Bertling, A. M. Schmidt, G. Bauer, T. Speck, Intern. Polym. Sci. Technol. 38(9), 1-4, (2011).
5) "Bio-inspired self-healing materials", T. Speck, M. von Tapavicza, A. Nellesen, A. M. Schmidt, R. Müllhaupt, at al. in: Materials design inspired by Nature: Function through inner Architecture, P. Fratzl, J. W. C. Dunlop, R. Weinkammer (eds.), RSC Publishing, (Feb 2013), ISBN: 978-1-84973-553-7
6) “Self Healing Ionomers”, N. Hohlbein, M. von Tapavicza, A. Nellesen, A. M. Schmidt, in: Self-Healing Polymers: from Principles to Applications, W. H. Binder (ed.),  Wiley-VCH Verlag GmbH,  (June 2013), ISBN-10: 3527334394