Fabrication of transparent glass fabric‐reinforced thermoplastic composite based on tow‐spreading technique

Abstract Highly transparent and mechanically robust thermoplastic composites have been developed by hot‐pressing PETG with E‐glass fabrics. The tow‐spreading technique facilitates the reduction of internal defects and fiber crimp angle in the composites, thereby significantly improving their optical and mechanical properties. The optimized composite containing 55.1 vol% glass fibers and 0.4 mm thickness has a high transmittance of 86.1%@616 nm and a low overall haze of 7.2%. Moreover, the 1 mm thick composites exhibit tensile strength of up to 340 MPa and impact strength of up to 86.3 kJ/m². After 28 days of hygrothermal or UV aging, the composites show minimal changes in their glass transition temperature and thermal degradation temperature. The chemical structure also remains unchanged, with no observed crystallization. In comparison to UV aging, the composites demonstrate better resistance against hygrothermal aging. Specifically, the hygrothermal aged sample displayed a light transmittance retention rate of 93.5% and a bending strength retention rate of 94.3%, while these values were reduced to 73.3% and 90.5%, respectively, in the UV aged sample. The opto‐mechanical properties enhanced mechanism and aging degradation mechanism have been identified by microscopic morphological observation. This work provides an innovative and straightforward approach to fabricate transparent, recyclable, high‐strength thermoplastic composites. Highlights Highly transparent, mechanically robust, recyclable glass‐fabric reinforced thermoplastic composites are fabricated. Composites with spread‐tow fabrics exhibits improved transparency. The fabrication route is scalable and cost‐effective. The mechanism for opto‐mechanical properties enhancement are proposed.