Industry is seeking new or modified materials to reduce embodied carbon/energy footprint and improve resource efficiency to meet targets [1-4] and reduce landfill costs, while maintaining functional requirements of applications. A solution that is gaining interest due to its potential for circular economy business models is the use of municipal waste streams to produce recyclable plastics. These waste streams are an underutilized resource because of the challenges that result from the batch-to-batch variability of the material feedstock and its conversion to a reliable material supply with desirable properties and performance. Designers and engineers need to manage the variability and explore applications appropriate for a recycled plastic with highly variable properties.

To support the management of property variability of recycled polymers for the design of engineering applications, the PRISM project [5] enabled solutions for: 1) a novel recycling process resulting in the commercialisation of municipal waste streams for plastics [6]; and, 2) simulation pathways to test the optimal use of a material with highly variable properties in design. Specifically, a combination of four software components (Ansys Granta MI, Space Claim, optiSLang, and LS Dyna) were used in optimisation workflows to handle the uncertainty of material properties alongside the ability to screen geometries for applications to replace virgin materials with higher embodied CO2/energy.

This work will share the strategy of the partners to establish an iterative workflow of material development linked with product requirements, that relies on digitalization of materials information and simulation to achieve a dramatic reduction in physical testing. Enabling redesign to fit the performance capabilities of the recycled plastic tested our preconceptions of how and where to use recycled materials for new applications. The simulation strategy considers first the material property behaviour by virtual coupon testing, followed by part simulation coupled with an optimization strategy to challenge geometry and material suitability. Both approaches can be used during the concept design phase and facilitate the definition of target properties for the material supplier of recycled content. The material and part design process from material screening through to the optimized design considers technical performance, cost and environmental sustainability, including regulatory compliance [7]. 

[1] End of Life Vehicle (ELV), EU Directive 2000/53/EC

[2] Waste Framework Directive, EU Directive 2008/98/EC

[3] A new Circular Economy Action Plan For a Cleaner and more Competitive Europe, COM/2020/98 [4] EU Green Deal, Communication March 2022

[5] PRISM (Plastics Recycling In Stochastic Modelling) funded by InnovateUK (May-21 to Aug-22), involving Impact Recycling Ltd, (Coordinator), Far-UK Ltd, Ansys UK Ltd (formerly Granta Design Ltd), Impact Laboratories Ltd.

[6] IMPACT Recycling, BOSS Technologies

[7] REACH Directive (EC 1907/2006)