However, a new approach to creating the fastenings and tabs for such devices based on the shape-memory effect in plastics could mean that disassembling such devices at end of life could be automated.
The approach would allow valuable components and metals to be recovered more efficiently from the millions of devices discarded every year, according to research to be published in the International Journal of Product Development.
Habib Hussein and David Harrison of the School of Engineering and Design at Brunel University, UK, explain that Europe's WEEE regulations, the Waste Electrical and Electronic Equipment directive, are aimed at tackling the growing stream of waste electrical and electronic goods in order to reduce landfill usage and waste that is incinerated. The regulations mean that there are now incentives to design equipment that is more recyclable.
"Product disassembly offers one method for reducing the landfill and enabling compliance with legislative targets by optimising the recovery of hazardous and valuable components during the recycling process. However, manual disassembly is a time-consuming and thus costly process, in terms of either financial or social impact," the researchers say.
They have now investigated the possibility of Active Disassembly using Smart Materials (ADSM). ADSM uses materials that can act as fasteners within a product, which at product end of life, can be undone simply by direct heating. This releases the fasteners causing the device case to fall apart without screws having to be undone or stiff clasps opened manually. This is one important design feature that might make recycling electronic devices with plastic cases much easier.
Their concept relies on the so-called shape memory effect in engineering plastics, or polymers. Plastics can be fabricated in one shape - the unfastened state - and then moulded a second time into a new shape - the fastened state. When the fastened state version is heated, the plastic will revert to its original, unfastened state, as it retains a molecular memory of the form in which it was originally produced.
The researchers have developed a case-fastening device based on one such shape memory polymer. Their tests demonstrated that lowering the device at end of life into hot water, leads to the fasteners reverting to their unfastened state and the case falling apart, on agitation. They have also shown that the fasteners retain their integrity for at least two years without disassembling spontaneously.
"Standard-engineering polymers may be used to produce reliable long-term shape memory effect fastening devices to enable the efficient end of life treatment of WEEE," the researchers conclude.
Albert Ang | alfa
Upcycling of PET Bottles: New Ideas for Resource Cycles in Germany
25.06.2018 | Fraunhofer-Institut für Betriebsfestigkeit und Systemzuverlässigkeit LBF
Dry landscapes can increase disease transmission
20.06.2018 | Forschungsverbund Berlin e.V.
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
19.07.2018 | Earth Sciences
19.07.2018 | Power and Electrical Engineering
19.07.2018 | Materials Sciences