Model will enable development of plastics with specific uses

Researchers at Leeds University and Durham University claim they have solved a long-standing problem that could change the way plastics are made.

The breakthrough, based on new mathematical models, will allow experts to create plastics with specific uses and properties. The plastics will also be easier to recycle than current versions.

‘Normally, people make a plastic and then see if it works. We have come up with a model that predicts how the stiffening will turn out,’ Dr Chinmay Das, a researcher at the School of Physics and Astronomy at Leeds University, told The Engineer.

‘If you want a particular kind of behaviour, normally people use trial and error to see which polymer works best. This is costly and bad for the environment.’

Another researcher on the project, Dr Daniel Read, from the School of Mathematics at Leeds University, said: ‘Up until now, nobody has been able to make a continuous link from the chemistry of plastics to the flow properties they possess by considering the individual molecules involved.

‘This new method could save the manufacturing industry time, energy and money. Up until now, the industry has developed plastics and then found a use for them,’ he continued.

‘Biopolymers are an area that our new methodology could be applied to, as companies continue to look beyond fossil fuels when making plastics. We hope that the code we’ve developed will enable scientists to home in on particular chemistries to develop these biopolymers,’ Read explained.

Peter Tillin, the engineering manager at Plastribution, added: ‘In theory, if you plot a recipe book and you say you want this plastic to possess these properties, then it would make life a lot easier. The thing is, I’d say in the main, there’s nearly every plastic available already.

‘If somebody comes to us and gives us a list of properties that they need, more often than not there’s already a plastic on the market to meet their criteria,’ he explained. 

The mathematical models developed by the researchers combine two pieces of computer code, which predict how the polymers will flow and the shape they will adopt when they are created.

The paper’s authors form part of the Microscale Polymer Processing project, a collaboration of academics and industry experts, which has spent 10 years exploring how to build better giant ‘macromolecules’. These long, tangled molecules are the basic components of plastics and dictate their properties during the melting, flowing and forming processes in plastics production.