Abstract Mechanical recycling of engineering polymers is frequently constrained by property degradation and uncertainty regarding their suitability for demanding applications. In this study, the degradation and recovery potential of post‐consumer acrylonitrile–butadiene–styrene (ABS) recovered from real service conditions was evaluated using an application‐informed material assessment framework. Virgin and end‐of‐life ABS were characterised in terms of rheological, thermal, and mechanical behaviour. The recycled material exhibited a pronounced increase in melt flow index (around 20%) together with reductions in stiffness and strength of 10–15%, consistent with molecular weight reduction, stabiliser depletion, and feedstock heterogeneity associated with post‐consumer use. Property recovery was subsequently investigated through controlled blending of post‐consumer ABS with virgin material at defined weight fractions. Blends were prepared by direct mixing during injection moulding to preserve industrial relevance and minimise additional thermomechanical degradation. Rheological behaviour and stiffness‐related mechanical properties exhibited a near‐linear dependence on virgin content, with coefficients of determination exceeding 0.9, enabling predictable interpolation consistent with mixture‐based behaviour. The recovered formulations were benchmarked against functional and processing requirements derived from an existing injection‐moulded ABS component, a command plate used in a toilet flush cistern, subjected primarily to quasi‐static loading and requiring dimensional stability and reliable mould filling. Within this functional context, flexural modulus and melt flow index were selected as application‐relevant acceptance parameters. All investigated formulations satisfied the specified requirements, while blends containing moderate virgin content exhibited reduced variability and improved robustness compared with fully recycled material. Overall, this work demonstrates a practical and predictive route for the valorisation of post‐consumer ABS through blending strategies that link degradation assessment, controlled property recovery, and functionally justified application benchmarking, supporting its reintegration into circular manufacturing systems. © 2026 Society of Chemical Industry.
Pereira et al. (Thu,) studied this question.