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Melt-spinning and the thermal decomposition of mixed polymers containing polysilsesquioxane and polycarbosilane

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Ken’ichiro Kita
Ken’ichiro Kita
Ken’ichiro Kita
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Manabu Fukushima at National Institute of Advanced Industrial Science and Technology
Manabu Fukushima
Mikinori Hotta
Mikinori Hotta
Mikinori Hotta
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Abstract and Figures

We attempted melt-spinning and investigated the compatibility and thermal decomposition of a mixture comprising polysilsesquioxane and polycarbosilane for the purpose of manufacturing low grade silicon carbide (SiC) fibers or silicon oxycarbide fibers. The fabrication approach was selected to reinforce the strength of the as-spun fibers, as well as increase the yield of long SiC fibers. Although the addition of polysilsesquioxane increased the viscosity of the mixed polymer, the mixed polymer could be melt-spun by incorporating a softener during the fabrication process. Cross-linking between polysilsesquioxane and polycarbosilane was successfully accomplished by heating them to 600 °C. Consequently, the mixed polymer demonstrated a higher yield in comparison to pure polycarbosilane. The as-spun fibers derived from the mixed polymer had a tensile strength approximately 10 times that of the fibers derived from pure PCS using an identical approach. Thus, we were able to confirm that blending polysilsesquioxane effectively reinforced the tensile strength of the as-spun fibers to generate long SiC fibers.
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POLYMERS & BIOPOLYMERS
Melt-spinning and the thermal decomposition of mixed
polymers containing polysilsesquioxane
and polycarbosilane
Ken’ichiro Kita
1,
* , Manabu Fukushima
1
, and Mikinori Hotta
1
1
National Institute of Advanced Industrial Science and Technology (AIST), 2266-98 Shimo-shidami, Moriyama-ku,
Nagoya 463-8560, Japan
Received: 27 December 2021
Accepted: 11 March 2022
Published online:
1 April 2022
ÓThe Author(s), under
exclusive licence to Springer
Science+Business Media, LLC,
part of Springer Nature 2022
ABSTRACT
We attempted melt-spinning and investigated the compatibility and thermal
decomposition of a mixture comprising polysilsesquioxane and polycarbosilane
for the purpose of manufacturing low grade silicon carbide (SiC) fibers or silicon
oxycarbide fibers. The fabrication approach was selected to reinforce the
strength of the as-spun fibers, as well as increase the yield of long SiC fibers.
Although the addition of polysilsesquioxane increased the viscosity of the
mixed polymer, the mixed polymer could be melt-spun by incorporating a
softener during the fabrication process. Cross-linking between
polysilsesquioxane and polycarbosilane was successfully accomplished by
heating them to 600 °C. Consequently, the mixed polymer demonstrated a
higher yield in comparison to pure polycarbosilane. The as-spun fibers derived
from the mixed polymer had a tensile strength approximately 10 times that of
the fibers derived from pure PCS using an identical approach. Thus, we were
able to confirm that blending polysilsesquioxane effectively reinforced the ten-
sile strength of the as-spun fibers to generate long SiC fibers.
Introduction
Silicon carbide (SiC) fibers offer significant promise
for the fabrication of lightweight ceramic matrix
composites (CMCs) that are highly resilient to phys-
ical stress and exhibit high thermal resistance [1–4].
Recently, considerable research has been conducted
on CMCs made of fibers [5]. Additionally, CMCs
have found propound use in a wide variety of
applications, including next-generation airplane
engines [5,6].
Following the successful production of SiC fibers
using polycarbosilane (PCS) as a precursor [7,8],
numerous studies have been conducted to improve
the fibers’ properties. In this regard, several studies
have focused on blending polymers with PCS.
Handling Editor: Gregory Rutledge.
Address correspondence to E-mail: kita.kennichiro@aist.go.jp
https://doi.org/10.1007/s10853-022-07103-0
J Mater Sci (2022) 57:7416–7421
Polymers & biopolymers
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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