Photon-powered composite fabrication: Advancing fiber-reinforced composites with light-induced systems

Abstract

Fiber-reinforced composites (FRCs) are advanced materials combining fibers (e.g., glass, carbon, aramid) with a polymer matrix to provide high strength, stiffness, durability, and lightweight properties. Traditional FRC manufacturing methods rely on thermal curing, which involves high energy consumption (often exceeding 100 °C for several hours) and long processing times, increasing production costs and limiting sustainability. To address these limitations, light-induced polymerization has emerged as a promising alternative. Light-induced polymerization, a process in which monomers are transformed into polymers through photoinitiators, offers spatial and temporal control, significantly reducing curing times to minutes while minimizing energy consumption. Unlike thermal curing, this method enables precise polymerization using various wavelengths of light, from UV to visible range, while reducing the need for toxic chemicals or solvents. Studies have demonstrated that UV-cured FRCs can achieve mechanical properties comparable to thermally cured composites, depending on the fiber content and resin formulation. Recent advancements, such as stepwise UV curing and radical-induced cationic frontal polymerization (RICFP), have improved light penetration, enabling uniform polymerization even in thick laminates (up to 20 mm). However, challenges such as limited light penetration due to fiber absorption and optical interference remain key barriers to widespread adoption. This review uniquely consolidates recent advancements in light-induced polymerization for FRC fabrication and critically evaluates strategies to overcome these challenges, including photoinitiator selection, diluent optimization, and wavelength tuning. By systematically discussing the role of photoinitiators, fiber types, fillers, and irradiation wavelengths, this work provides novel insights into the chemistry, processing strategies, and future directions of this emerging technology.