Interlaminar fracture toughness, thermal conductivity and electromagnetic wave absorption of CF/EP composites with SiCnw‐loaded polypropylene nonwoven fabrics interleaves

Abstract The synergistic improvement of interlaminar toughness, thermal conductivity, and electromagnetic wave absorption of carbon fiber/epoxy (CF/EP) composites is a far‐reaching and challenging research work. In this study, CF/EP composites with SiC nanowires (SiCnw) loaded polypropylene nonwoven fabrics (PPNWF) interleaves were prepared by mold pressing process. The effect of SiCnw‐loaded PPNWF on the mechanical properties, thermal properties, DMA, and reflection loss of CF/EP composites was investigated. The results showed that the G_IIC and thermal conductivity of SiCnw/PPNWF/CF/EP composites with PPNWF surface density of 10 g/cm² were 1285.4 J/m² and 0.75 W·m⁻¹·K⁻¹, respectively, which were 65.6% and 92.3% higher than those of CF/EP composite, respectively. The impact strength of PPNWF/CF/EP composites reached 253.4 kJ/m² with a PPNWF face density of 20 g/cm², which was 29.9% higher than that of CF/EP composites. The reflection loss of SiCnw/CF/EP composite reached −17.57 dB at 1.96 GHz with a thickness of 7.5 mm, which was 258% lower than that of CF/EP composite. DMA tests showed that the T_g of SiCnw‐loaded PPNWF modified CF/EP composites was higher than that of CF/EP composites. This work was of great significance to broaden the high‐end applications of composite materials. Highlights SiCnw‐loaded polypropylene nonwoven fabrics were used as interleaves. SiCnw‐loaded PPNWF synergistically improved the properties of CF/EP composites. Improvement of integration of structure and function of CF/EP composite.