Main feature of the technology is the deliberate control of the orientation of reinforcing elements in polymer-based advanced composites.
Image: 3D-oriented reinforcing platelets
The technology relies on the use of magnetic nanoparticles to enable the orientation of non-magnetic reinforcing particles (e.g. platelets, fiber, rods) in a fluid, followed by the consolidation of the aligned structure.
Composite materials with reinforcing particles embedded in a matrix material are extensively used in construction, aerospace, automobile and medical industries. These composites employ continuous or discontinuous fibres to reinforce polymeric matrices. Though this reinforcement enhances the mechanical strength and stiffness of the matrix, it is limited to one specific direction. 3-D reinforcement remains challenging due to the limited control of particles in the out-of-plane direction. Recent attempts to solve this issue involve synthetic procedures that show nominal improvements.
Small quantities of magnetic nanoparticles (below 0.01% by volume) are temporarily attached to the reinforcement particle of interest. The reinforcing particle is then combined with the polymer precursor material that is subsequently cross-linked or solidified. The application of a low magnetic field is required to orient the reinforcing particles (see: Image). The surprisingly low magnetic fields required to achieve orientation allow for the use of conventional, cheap magnets to achieve platelet alignment. After the matrix is consolidated, the magnetic nanoparticles can be removed without effect on the reinforced composites.
Advantages of this technology are the highly improved material properties expressed in a 10-fold increase in compression stiffness perpendicular to the film surface, the possibility to deploy coatings with 10-fold smaller out-of-plane thickness, the low magnetic fields required for alignment and low magnetic nanoparticles content required and the enhanced options in component design by the control to locally reinforce regions of high stress concentration.
We are looking for industrial partners interested in exploiting our technology via new products i.e., new product design. Stefan Lux and Marjan Kraak of ETH transfer will be present at the TechConnect Emerging Technology Showcase in Boston June 14 and 15.
IP Background:
Organization: Swiss Federal Institute of Technology (ETH Zurich)
Inventors: André Studart, Randal Erb, Rafael Libanori
Primary markets: Advanced Materials, Biomedical engineering, Dental restoration, Power engineering.
Technology Contact: Stefan Lux, ETH transfer, ETH Zurich, Switzerland
