An emulsion-based route to generate magnetic capsules for concrete applications
The deterioration of reinforced concrete structures due to corrosion of the reinforcement bars has a major ecological and economical impact worldwide. Increased corrosion inhibition shall be allowed by placing polyurea capsules containing water soluble chemicals that protect the steel such as calcium nitrite. The capsules are modified with iron oxide nanoparticles to generate a magnetic susceptibility of the capsules. The iron oxide particles are introduced to the process in the preliminary step of emulsification of the water phase. The magnetic property can be possibly used to attract the capsules by running current through the steel wires which induces a magnetic field around them. The corrosion inhibiting property emerges when necessary after cracks in the concrete matrix penetrate to the steel bars which facilitates water with dissolved salts to reach the metal surface. The cracks cause the polymer wall of the capsules to break and release the chemicals stored inside. The work presents the route to produce the magnetically modified capsules containing calcium nitrite as corrosion inhibiting compound and gives an outlook on future work. Increased corrosion inhibition in reinforcement bars leading to an extended service life of concrete structures is expected to be highly beneficial for worldwide industry.^
Engineering, Chemical|Nanotechnology|Engineering, Materials Science
Lennart Max Kleinfeldt,
"An emulsion-based route to generate magnetic capsules for concrete applications"
Dissertations and Master's Theses (Campus Access).