Lifecycle analysis of nanotechnology-enhanced soft materials in the circular economy

Nanotechnology-enhanced soft materials, ranging from polymers and gels to bio-based composites, offer improved functionality and durability across diverse sectors. As their use grows, assessing their environmental sustainability within the circular economy framework is critical. This study applies life cycle assessment (LCA) to evaluate the environmental impacts of these materials across production, use, and end-of-life stages. Findings reveal that while nanomaterials often incur high production impacts, especially in energy use and toxicity, their enhanced performance can offset these burdens during use. Green synthesis, renewable energy, and design-for-environment strategies show promise in reducing lifecycle impacts. This is the first conceptual review that systematically maps nanomaterial design features, such as synthesis routes, surface properties, and morphologies, to environmental performance metrics including energy use, toxicity, and end-of-life behavior. This study uniquely integrates a keyword co-occurrence analysis using the PRISMA methodology to identify thematic research clusters and underexplored intersections between nanotechnology, life cycle analysis, and circular economy. The network and density visualization maps provide further critical insights into the existing knowledge paving the path towards identification of underexplored keywords. By combining bibliometric analysis with design-performance mapping, this work pioneers a novel framework to guide future interdisciplinary research and sustainability assessments in the field. However, methodological gaps in LCA, such as the lack of nano-specific data and characterization factors, hinder comprehensive assessment. The study emphasizes the need for improved LCA models, stakeholder collaboration, and innovation management to support the sustainable integration of nanotechnology in circular value chains.