The sustainability challenges across the plastic value chain, ranging from raw material extraction to end-of-life management, remain a critical barrier to circular economy advancement. While Life Cycle Assessment (LCA) has been widely adopted to quantify environmental impacts, it often falls short in addressing the dynamic, multi-actor, and multi-dimensional nature of decision-making. The current thesis addresses this gap by developing an integrated methodological framework that combines LCA with complementary analytical tools to support context-specific sustainability decisions. The framework is structured around the key stages of the plastic value chain, i.e., raw material production, product manufacturing, consumption and use, and end-of-life (EOL) treatment.
For raw material production stage, a systematic literature review and meta-analysis of 130 peer-reviewed LCA studies is conducted to identify performance trade-offs of bioplastics compared to fossil-based plastics. The product manufacturing stage is examined using a system dynamics model that simulates temporal feedback among material flows, environmental impacts, and product strategy interventions. Consumer engagement is addressed through a Stackelberg game-theoretic model that explores the interaction between regulators and consumers under different incentive schemes. In the EOL phase, a cooperative game-theoretic approach is applied to allocate environmental burdens more fairly among stakeholders in the plastic waste management system to increase their contribution for plastic recycling. A social impact assessment is conducted across the entire value chain, and a holistic sustainability evaluation is developed by integrating environmental, economic, and social dimensions to support balanced decision-making.
The findings highlight the substantial variation in the environmental performance of bioplastics, driven by differences in feedstock types and methodological choices; the non-linear impact of product strategy interventions on long-term material transitions; the critical role of incentive alignment in reducing plastic leakage and fostering sustainable consumption; and the importance of accepted burden allocation mechanisms in supporting long-term collaboration among stakeholders in plastic recycling. The social impact assessment further identifies stakeholder-specific vulnerabilities, while the integrated sustainability evaluation enables a clearer understanding of trade-offs and synergies across environmental, economic, and social dimensions.
This thesis contributes to both theoretical and practical advancements by integrating LCA with dynamic and strategic modelling tools, offering a transferable framework for tackling complex sustainability issues in material systems. The insights aim to support researchers, policymakers, and industry stakeholders in developing more adaptive and inclusive strategies for sustainable plastic governance and beyond.