C/C–SiC composites derived from single‐source poly(silylene–acetylene) precursors

Abstract

Carbon-fiber-reinforced carbon-silicon carbide (C/C-SiC) composites were prepared by impregnating carbon fibers with ethynylphenyl-terminated poly(silylene-acetylene) (EPTSA) as a single-source precursor with subsequent hot pressing and pyrolysis. The structural evolution, crystallization behavior, and graphitization of bulk C-SiC ceramics, as well as their mechanical properties and ablation behavior, were investigated. The EPTSA precursor starts to transform into inorganic SiC ceramic materials at 800 • C, which is characterized by an amorphous structure with weight loss, shrinkage, and densification between 800 and 1000 • C. The formation of SiC crystals inhibited the growth of the graphitic structure between 1000 and 1200 • C. As the temperature was raised, both graphite and SiC crystals continued to grow, and the crystalline forms became more complete. The carbon-fiber cloth (T300CF)-reinforced C-SiC composite (T300CF/C-SiC) prepared using polymer infiltration and pyrolysis (PIP) exhibited excellent mechanical properties. After five PIP cycles, the flexural strength, flexural modulus, and interlaminar shear strength of the T300CF/C-SiC composite reached 169 MPa, 32.5 GPa, and 9.38 MPa, respectively. In addition, the chopped-carbon-fiber-reinforced C-SiC composite fabricated using the PIP process demonstrated good oxyacetylene-torch ablation properties.

Heat-Resistant Dendritic Poly(methylsilane arylacetylene) with Attractive Mechanical Properties Enhanced Via Higher Curing Temperature

“…1−4 Moreover, cured PSA resins appear to have excellent and stable dielectric properties in wide temperature and frequency ranges, 5 and they can be further pyrolyzed, forming β-SiC ceramics over 1000 °C. 6 Hence, PSA resins can be used as ablation-resistant, heat-proof, wave-transmitting, and high-temperature insulating materials. However, the poor mechanical properties of cured PSA resins limit their application.…”

“…Poly­(silylene arylacetylene) (PSA) resins composed of [−Si–CC–Ar–CC−] units have attracted much attention because of their excellent thermal stability. − Moreover, cured PSA resins appear to have excellent and stable dielectric properties in wide temperature and frequency ranges, and they can be further pyrolyzed, forming β-SiC ceramics over 1000 °C . Hence, PSA resins can be used as ablation-resistant, heat-proof, wave-transmitting, and high-temperature insulating materials.…”