Improving surface interactions of waste plastics as grain substitutes within concrete

The cement industry is one of the biggest CO2 emitters on the planet and concurrently, we are facing a global crisis in plastic waste and how to repurpose, reuse or recycle it rather than disposing of it in landfill/incineration.

This multi-sector project aims to tackle both issues through the use and optimisation of polymeric waste streams as organic binders for high performance concrete composites. Whilst not a new idea, the inclusion of waste polymers in concrete has been found to degrade the mechanical properties of concrete compared to standard concrete.

We therefore seek to address these limitations by applying a ‘bottom-up’ approach to aggregate-inorganic oxide surface interactions and material performance. Specifically, this research will study the chemistry of interactions between calcium oxide and functional groups present in waste polymeric materials to allow correlation and insight on these interactions and optimise the final polymer-concrete composite. The project will develop improvements in the strength of these polymer-metal oxide interactions through modification of the surface functionality of the polymer waste. The success of this project will allow concrete to be ‘dematerialised’ by using less raw material, reduce costs through the use of ‘zero/negative-value’ polymer waste streams in concrete whilst also improving mechanical properties of the final polymer-concrete composite.

James Railton

Northumbria University