Fabrication of hierarchically porous silicon carbonitride monolith using branched polysilazane and freeze casting method without crosslinking step: Effect of polymer additive to aligned macropore structure

A hierarchically porous SiCN monolith with aligned macropores was prepared using a branch‐structured polysilazane, silsesquiazane (SSQZ), as a precursor and polymer additive, through the freeze casting method. As polymer additives, polystyrene (PS) and poly(methyl methacrylate), which have different...

Full description

Saved in:
Bibliographic Details
Published in:Journal of the American Ceramic Society 2022-12, Vol.105 (12), p.7785-7794
Main Authors: Huh, Tae‐Hwan, Lee, Taek Seung, Kwark, Young‐Je
Format: Article
Language:English
Subjects:
Additives
Crosslinking
Dimensional stability
freeze casting
hierarchically porous structure
Molecular weight
polymer additive
Polymers
Polymethyl methacrylate
Polysilazane
Polystyrene resins
Pore formation
Pore size
Porous silicon
Prepolymers
Silicon carbonitride
silsesquiazane
Structural stability
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:A hierarchically porous SiCN monolith with aligned macropores was prepared using a branch‐structured polysilazane, silsesquiazane (SSQZ), as a precursor and polymer additive, through the freeze casting method. As polymer additives, polystyrene (PS) and poly(methyl methacrylate), which have different compatibilities with SSQZ, were used to confirm the effect on the pore formation. In addition, the pore formability according to the molecular weight was investigated using PSs with different molecular weights. When the SSQZ and high‐molecular‐weight PS (HPS) were used, a porous SiCN with micro/meso/macropore structure could be fabricated because of the structural stability of the SSQZ and high molecular weight of HPS. The hierarchically porous SiCN monolith was successfully manufactured using SSQZ and HPS with 639 m2/g of specific surface area, 0.36 cm3/g of pore volume, and 2.1 nm of average pore size. The hierarchically porous SiCN monolith with high HPS content has improved dimensional stability to show its compressive fracture energy.
ISSN:0002-7820
1551-2916
DOI:10.1111/jace.18714