POS3-0309
Support-Polymer Tg as a Design Parameter for Pore Stabilization in Electrospun Preceramic Fibers
When and Where
Nov 30, -0001
12:00am - 12:00am
Presenter(s)
Seung-O Choi (Soongsil University)
Co-Author(s)
Abstract
Preceramic polymer-derived ceramic fibers are promising platforms for catalysis and adsorption owing to their tunable composition and retained polymer processability. We previously demonstrated that (phenyl)silsesquiazane (PSSQZ) can be electrospun using poly(ethylene oxide) (PEO) as an auxiliary polymer, and that nonsolvent-induced phase separation (NIPS) via a CHCl₃/decane solvent/nonsolvent system enabled the formation of porous fiber structures. However, the low Tg of PEO led to pore collapse during annealing and pyrolysis, preventing stable retention of the NIPS-derived pore network.
Herein, we investigated the role of support-polymer Tg as a design parameter for pore stabilization in electrospun PSSQZ fibers. PSSQZ was blended with support polymers of varying Tg at a 9:1 (w/w) ratio and electrospun under the same NIPS conditions, followed by humid annealing and pyrolysis at 700 °C under N₂.
We found that low-Tg support polymers promoted segmental mobility during annealing, allowing NIPS-derived pores to collapse prior to ceramic fixation — consistent with the behavior previously observed for PEO. In contrast, high-Tg support polymers suppressed pore-wall rearrangement, preserving an open and interconnected pore network through pyrolysis. Additionally, the incorporation of nickelocene promoted turbostratic carbon formation and lowered the ceramization barrier, contributing to earlier structural fixation and further pore stabilization.
This work establishes support-polymer Tg as a rational design parameter for pore preservation, providing a practical route to porous PSSQZ-derived ceramic fibers with well-defined interconnected pore networks for catalyst-support and adsorption applications.
Herein, we investigated the role of support-polymer Tg as a design parameter for pore stabilization in electrospun PSSQZ fibers. PSSQZ was blended with support polymers of varying Tg at a 9:1 (w/w) ratio and electrospun under the same NIPS conditions, followed by humid annealing and pyrolysis at 700 °C under N₂.
We found that low-Tg support polymers promoted segmental mobility during annealing, allowing NIPS-derived pores to collapse prior to ceramic fixation — consistent with the behavior previously observed for PEO. In contrast, high-Tg support polymers suppressed pore-wall rearrangement, preserving an open and interconnected pore network through pyrolysis. Additionally, the incorporation of nickelocene promoted turbostratic carbon formation and lowered the ceramization barrier, contributing to earlier structural fixation and further pore stabilization.
This work establishes support-polymer Tg as a rational design parameter for pore preservation, providing a practical route to porous PSSQZ-derived ceramic fibers with well-defined interconnected pore networks for catalyst-support and adsorption applications.
