Filling the Gaps: Tracing 12 Types of Non-commodity Plastics in China's Plastic Socioeconomic Metabolism.

Recent plastic flow research has largely focused on commodity plastics (PE, PP, PVC, PS, ABS), yet a sizable share of other polymer types remains understudied. These non-commodity plastics suffer from inconsistent definitions, complex classifications, and data gaps, which hinder accurate assessment of their production, use, and end-of-life management. This study develops dynamic material flow analysis to investigate 12 key "non-commodity" plastics in China─including PET, PU, seven engineering plastics, and three thermosetting plastics─and addresses these knowledge gaps.