Researchers at the University of Sussex have developed a glue which can unstick when placed in a magnetic field and reduce landfill waste. The adhesive works with plastic, wood, glass and metal and in terms of strength, is comparable to those currently used in industry.
Currently, items like mobile phones, microwaves and car dashboards are assembled using adhesives. It is a quick and relatively cheap way to make products but, due to problems dismantling the various materials for different recycling methods, most of these products will be destined for landfill.
However, Dr Barnaby Greenland, Lecturer in Medicinal Chemistry, working in conjunction with Stanelco RF Technologies Ltd and Prof Wayne Hayes at the University of Reading, have found a solution.
New Adhesive Containing Tiny Metal Particles
In a new research paper, published by the European Polymer Journal, Dr Greenland and the team describe a new type of adhesive which contains tiny particles of metal. When passed through an alternating electromagnetic field, the glue melts and products simply fall apart.
Dr Greenland said, “
In as little as 30 seconds, we can unstick items using a relatively weak magnetic field.”
A power source connected to an inductor creates the electro-magnetic field which produces heat in the metal particles within the glue and effectively melts it so that the various materials that were previously held together are separated.
“
There’s little glue residue left over – although this wouldn’t be a problem for metal objects which are melted down for recycling anyway. Using these specific levels of magnetic field to heat is also incredibly safe. The energy only heats the metal specks in the glue, so we could place our bare hands in the field and feel absolutely no heat at all” added Dr Greenland.
Thermal Adhesive Friendly Formula
In principle, the formula could be applied to any thermal adhesive making it an innovation which could be incorporated into industry relatively easily.
Dr Greenland said, “
In essence, we could have a big conveyor belt of products going through a magnetic field where they enter fully assembled and come out the other end completely dismantled.”
The glue has provided a simple and green solution to quite a large problem. Currently glued products can often only be dismantled using chemicals. The new adhesive will save items from going to landfill and also reduce the use of potentially harmful substances.
The team have also demonstrated that this heating technique can be used to stick items together and will focus on investigating the process further.
Source: University of Sussex