γ‐ <scp>AlOOH</scp> ‐Assisted Immobilization of Antioxidants on Glass Fabric to Enhance Mechanical Properties and Durability of Composites in Alkaline Environments

ABSTRACT Enhancing the durability of ultraviolet‐cured‐in‐place pipe (UV‐CIPP) in alkaline environments remains challenging due to its long‐term exposure to concrete pore solution from the original pipe. Herein, a novel strategy that γ‐AlOOH coating assists to immobilize Irganox 1010 onto glass fibric (GF) was proposed for simultaneously improving alkaline corrosion resistance and mechanical properties of UV‐CIPP. Through the beneficial bridging of γ‐AlOOH with the coupling agent, Irganox 1010 was immobilized on the GF (GF‐Al‐g‐1010) surface through hydrogen bonding and covalent bonding. The leaching of Si 2+ from the GF backbone of unsaturated polyester resin (UP)/GF‐Al‐g‐1010 composite was reduced by 40.60% and the hydrolyzed alcohol products decreased by 47.1%. Meanwhile, the mechanical properties of UP/GF‐Al‐g‐1010 remained well preserved. The flexural and tensile modulus retained at 99.0% and 96.3%, respectively. The immobilization of Irganox 1010 at the UP/GF interface formed a protective hydrophobic layer and stabilized free radicals, which together inhibited resin degradation and reduced interface debonding. Moreover, the flexural strength and modulus of composites increased by 36.5% and 38.4%, respectively. The chemical bonding between GF‐Al‐g‐1010 and UP chains enhanced interfacial adhesion. In summary, this work will facilitate the design of UV/thermal dual‐cured composites with high strength and alkaline corrosion resistance for pipeline rehabilitation.