Utilization of surface modified UHMWPE nonwoven fiber surfaces as interlayers to improve the fracture toughness in carbon-fiber reinforced polymer composites
ENGINEERING FRACTURE MECHANICS, cilt.346, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 346
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.engfracmech.2026.112605
- Dergi Adı: ENGINEERING FRACTURE MECHANICS
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Applied Science & Technology Source, Compendex, INSPEC, Academic Search Ultimate (EBSCO), Engineering Source (EBSCO)
- Bursa Uludağ Üniversitesi Adresli: Evet
Özet
This study presents the first systematic investigation of the effect of ultra-high-molecular-weight polyethylene (UHMWPE) nonwoven fibers on the fracture toughness of carbon/epoxy composites. UHMWPE nonwovens were surface-modified by ozone and ultraviolet-C (UV-C) treatments to improve fibre-matrix adhesion. Ozonation was performed at gas flow rates of 5 and 15 L/min for 60 and 120 min corresponding to ozone concentrations of 10 and 7.5 g/h, respectively. UV-C treatment was carried out at 254 nm using 18 lamps with a total power of 470 W for 20 min with both sides of the nonwoven exposed to irradiation. Surface modified UHMWPE nonwoven interlayers are proposed as a novel, scalable, and effective toughening strategy to improve interlaminar damage resistance. The inherently inert UHMWPE surfaces were activated by ozone and UV treatments, and the resulting chemical and morphological changes were characterized by Xray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Ozone treatment increased the concentration of oxygen-containing functional groups, reducing carbon-carbon and carbon-hydrogen bond content from 96.4% to 72.4%, while UV treatment increased surface hydroxyl group content to 4.6%. Incorporation of an untreated UHMWPE interlayer increased impact strength by approximately 15%, whereas ozone- and UV-treated interlayers resulted in improvements of 25-35%. Mode I interlaminar fracture toughness (GIc) increased significantly after surface modification, with ozone-treated interlayers showing the greatest enhancement due to improved fiber-matrix adhesion and effective fiber bridging. In contrast, UV-treated interlayers provided superior mode II fracture toughness (GIIc), attributed to enhanced surface fibrillation and energy dissipation. Fractographic SEM analysis confirmed crack deflection, interlayer bridging, and fiber pull-out as the dominant toughening mechanisms. Overall, the findings demonstrate efficient mode-dependent toughening in carbon fiber reinforced polymer (CFRP) laminates. Keywords: Carbon fiber reinforced composites, fracture toughness, UHMWPE fiber, surface treatment.