Publication Date:
2018
Description:
Silicon carbide (SiC) monoliths with β‐SiC nanocrystals, good mechanical integrity, large SSA, and hierarchical pores were successfully fabricated via a sequence of procedures including the catalyst‐free hydrosilylation reaction‐induced phase separation, ambient‐pressure drying, calcination, and HF etching.
Abstract
Hierarchically porous silicon carbide (SiC) monoliths were fabricated based on polycarbosilane (PCS), divinyl benzene (DVB), and decalin, by a sequence of procedures including catalyst‐free hydrosilylation reaction‐induced phase separation, ambient‐pressure drying, calcination, and HF etching. The influences of ratios of each component on the phase separation were systematically studied. It was found that isotactic polypropylene added as a nonreactive additive could effectively tailor the microstructure and improve the mechanical properties of SiC monoliths. The resultant SiC monoliths mainly consisted of β‐SiC nanocrystals, and possessed low bulk density (0.7 g/cm3), high porosity (78%), large specific area (100.6 m2/g), high compressive strength (13.5 ± 1.6 MPa), and hierarchical pores (macropores around 350 nm, mesopores around 4 and 20 nm). These properties make SiC monoliths promising materials for catalyst/catalyst support, gas separator, and the reinforcement of high‐temperature composites.
Print ISSN:
0002-7820
Electronic ISSN:
1551-2916
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
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