Sustainable polypropylene chair: A life cycle assessment and cost analysis of industrial production

Due to their multiple properties, including flexibility, lightness, and strength, thermoplastics are an essential material in the development of processes at both industrial and domestic levels. However, thermoplastics are often derived from polymers synthesized using non-renewable petroleum resources. This has environmental consequences. The following research is proposed as the first environmental and economic impact evaluation of the extrusion and molding process of polypropylene (PP) generated by an industrial site for monobloc plastic chair production, through a Life Cycle Assessment (LCA) and Cost Analysis (CA) methodology. The analysis was conducted using SimaPro v10.1 software, Ecoinvent v3.10 database, and ReCiPe 2016 v1.07 impact assessment method. This study proposes multiple mitigative scenarios applicable to reduce the business-as-usual impact. Primary data was collected in 2024. The results show a significant environmental impact reduction caused by the substitution of the virgin PP with the recycled PP (-39%), a lower one generated by the substitution of the Italian country energy mix with the adoption of renewable energy sources (-12%), and a global added reduction obtained summarizing the two alternatives (-55%). The economic impacts are, instead, slightly influenced by the change in input raw materials, due to similar market costs. However, the cost reductions associated with the change in energetic source can be considered not negligible, excluding the plant design and commissioning costs. This research provides decision-makers with valuable guidance for implementing PP production plants, promoting sustainability and a circular economy. Advancing these prerogatives supports the achievement of Sustainable Development Goals, particularly SDGs 3, 11, and 13.