Turbine-to-Textile: Upcycling Wind Turbine Blade Waste into High-Performance PAN Composite Fibers

Recycling wind turbine blades (WTBs) is challenging due to their thermoset glass fiber-reinforced plastics (GFRPs), which resist chemical and thermal processing. Current methods yield low-value byproducts, underscoring the urgent need for scalable, high-value upcycling technologies. This study explores the reinforcement of polyacrylonitrile (PAN) matrix fibers using glass fibers (GFs) recovered from WTB, aiming to develop high-performance, sustainable composite materials. A systematic investigation was conducted to assess the influence of both GF concentration and layer number on the crystallinity and mechanical properties of PAN fibers. Structural evolution was characterized using differential scanning calorimetry (DSC), X-ray diffraction (XRD), and dynamic mechanical analysis (DMA), while mechanical behavior was evaluated through tensile testing. For the 256-layered fibers, the incorporation of GF increases the activation energy for cyclization by 17.75%, rising from 114.36 kJ/mol in pure PAN fibers to 134.56 kJ/mol in PAN-GF composites. XRD analysis also revealed a significant increase in crystallinity from 46.33% in PAN to 68.56% in PAN-GF. A corresponding increase in crystallite size was observed, suggesting that GF serves as a structural template, promoting PAN chain alignment and enhanced microstructural ordering. This integrated approach demonstrates the effectiveness of incorporating GF, thereby providing valuable insights into the relationship between fiber architecture and interfacial engineering while highlighting a promising pathway for upcycling end-of-life WTB components into advanced functional materials.