This review explores the potential of mechanochemistry in sustainable polymer degradation, focusing on both de novo developed designer polymers and existing waste streams. It highlights the historical development of polymer mechanochemistry and recent advancements in mechanochemically induced polymer degradation. The review also discusses theoretical and computational frameworks that can aid in the discovery and understanding of new mechanochemical reactions. Additionally, it examines the convergence of polymer and trituration mechanochemistry, emphasizing the need for interdisciplinary research to overcome challenges in scalability and application. The article covers the use of mechanophores for accelerated polymer degradation, ceiling temperature engineering, and the challenges and opportunities in computational elucidation of mechanochemical reactivity. It also discusses macroscopic models for mechanochemical bond scission and the mechanochemical recycling of bulk polymers to small molecules, addressing key issues such as selectivity, degradation rate, and thermodynamic driving forces. The review concludes by discussing the advantages of mechanochemical approaches over other chemical recycling strategies and the importance of spectroscopic analysis for understanding reaction mechanisms during ball milling.This review explores the potential of mechanochemistry in sustainable polymer degradation, focusing on both de novo developed designer polymers and existing waste streams. It highlights the historical development of polymer mechanochemistry and recent advancements in mechanochemically induced polymer degradation. The review also discusses theoretical and computational frameworks that can aid in the discovery and understanding of new mechanochemical reactions. Additionally, it examines the convergence of polymer and trituration mechanochemistry, emphasizing the need for interdisciplinary research to overcome challenges in scalability and application. The article covers the use of mechanophores for accelerated polymer degradation, ceiling temperature engineering, and the challenges and opportunities in computational elucidation of mechanochemical reactivity. It also discusses macroscopic models for mechanochemical bond scission and the mechanochemical recycling of bulk polymers to small molecules, addressing key issues such as selectivity, degradation rate, and thermodynamic driving forces. The review concludes by discussing the advantages of mechanochemical approaches over other chemical recycling strategies and the importance of spectroscopic analysis for understanding reaction mechanisms during ball milling.