相分离浸润剂对玻璃纤维环氧树脂复合材料界面的增强增韧研究OA

Glass fiber reinforced epoxies(GREs)are widely used in aerospace,wind power,and other fields,where the interface is a critical factor determining overall mechanical performance.Modifying glass fibers by sizing a-gents with phase separation structures to construct phase separation structures at interface can enhance both interfacial strength and toughness,resolving the inherent strength-toughness trade-off.However,the high-temperature curing required for GREs preparation disrupts intermolecular hydrogen bonds in sizing agents and destroys their phase separa-tion structures.To address this challenge,we developed a novel polyurea(PU40)as sizing agent with phase separa-tion structures for glass fiber modification and proposed a"room-temperature/high-temperature synergistic curing"strategy for GREs fabrication.During room-temperature curing,PU40 reacts with epoxy to form interpenetrating poly-mer networks(IPNs),locking the phase separation structures.In the subsequent high-temperature curing,hydrogen bonds weaken,but the IPNs maintain structural integrity.This successfully constructs the phase separation structures at interface.GREs prepared with PU40-modified glass fibers using this synergistic strategy achieved an interfacial shear strength(IFSS)of 30.2 MPa and interfacial fracture toughness of 59.7 J·m-2.Compared with both unmodified systems and those cured solely at high temperature,interfacial performance is significantly enhanced.This work pro-vides a new pathway for developing high-performance GREs.