Multifunctional Transparent Glass Fiber‐Reinforced Thermoplastic Composites With Self‐Cleaning Performance, Enhanced Durability, and Damage Self‐Reporting Capability

Abstract

Transparent glass fiber‐reinforced polymer composites (tGFRPs) are promising for photovoltaic and architectural applications, but surface contamination, poor self‐cleaning capability, and limited durability hinder their practical use. In this study, highly transparent PETG‐based tGFRP laminates were fabricated through hot‐pressing optimization, yielding a maximum transmittance of 80.9% and a haze of 11.6%. Two transparent organic–inorganic hybrid hydrophobic coatings with different organosilane compositions were then prepared via a sol–gel process. Both coatings formed dense surface layers, reduced surface roughness, and improved optical performance, with transmittance increasing to 81.8% and 83.1% and haze decreasing to 10.9% and 10.1%, respectively. Meanwhile, the coatings transformed the laminate surface from hydrophilic to hydrophobic, with water contact angles of 110.3° and 129.7° and sliding angles of 12.3° and 8.5°, respectively. The octyl‐containing coating showed better self‐cleaning and anti‐fouling performance, whereas the methyl‐functional coating exhibited superior mechanical and chemical durability. In addition, tGFRP showed damage self‐reporting capability through transparency attenuation during tensile loading, and the local transparency variation correlated well with the DIC strain distribution. These findings provide a feasible strategy for developing multifunctional transparent composites with combined surface functionality and damage self‐reporting capability.