Iron oxide nanoparticles for magnetically-triggered healing of bituminous materials
2016 (English)In: Construction and Building Materials, ISSN 0950-0618, E-ISSN 1879-0526, Vol. 112, 497-505 p.Article in journal (Refereed) PublishedText
Healing of micro-cracks is crucial for recovering the mechanical properties and extending the service time of bituminous materials. However, crack closure is often challenged by the efficiency and repeatability of the healing process or its technical and economic feasibility for large-scale applications. Here, we propose an innovative method to close micro-cracks in bituminous materials by using magnetically-triggered iron oxide nanoparticles as heating agents. Heating is generated through the so-called hyperthermia effect upon exposure of the nanoparticles to an external oscillating magnetic field. When mixed in a low volume fraction of 1% within bitumen, the nanoparticles generate enough heat to decrease the viscosity of the surrounding material and thus promote crack closure. Oleic acid is used to coat the iron oxide nanoparticles and enable their homogeneous distribution in the bitumen. Because of high hysteresis losses, γ-Fe2O3 nanoparticles with a mean crystallite size of 50 nm exhibited specific absorption rates (SAR) as high as 285 W/g when subjected to a magnetic field of 30 mT at 285 kHz. In contrast to the relatively slow heating of electrically-conductive additives, we find that iron oxide nanoparticles pre-embedded in bitumen allows for crack closure in a few seconds when subjected to similar magnetic field conditions. This represents a new efficient way to heal damage in thermoplastic road pavements in the presence of mineral aggregates.
Place, publisher, year, edition, pages
Elsevier, 2016. Vol. 112, 497-505 p.
Bitumen, Bituminous materials, Crack healing, Dynamic polymers, Magnetic field, Magnetic nanoparticles, Crack closure, Cracks, Crystallite size, Iron, Magnetic fields, Magnetism, Metal nanoparticles, Nanomagnetics, Nanoparticles, Crack-healing, Electrically conductive, Homogeneous distribution, Large-scale applications, Magnetic nano-particles, Oscillating magnetic fields, Specific absorption rate, Iron oxides
IdentifiersURN: urn:nbn:se:kth:diva-186941DOI: 10.1016/j.conbuildmat.2016.02.159ISI: 000375166900049ScopusID: 2-s2.0-84960154981OAI: oai:DiVA.org:kth-186941DiVA: diva2:929430
Funding Details: 200021-144269/1, SNSF, Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung
QC 201605182016-05-182016-05-162016-05-20Bibliographically approved