Large-scale spinning of high-performance SiO2 porous
nanofibers remains a pivotal challenge in facilitating their utilization
for flexible thermal insulation purposes. Herein, massive spinning
of SiO2 porous nanofibers was achieved through the solution
blow spinning (SBS) process utilizing microemulsion polysiloxane solutions.
Using MK siloxane polymer as the Si source, a solution characterized
by high purity and excellent uniformity was obtained. Multicomponent
spinnable microemulsion precursor was prepared by incorporating paraffin
as the sacrificial phase, Span 80 and Tween 80 as surfactants, and
polyvinylpyrrolidone as the spinning aid. Through optimization of
the spinnable solution composition and SBS process parameters, high-speed
spinning of paraffin/MK precursor nanofibers was accomplished with
a rate of 20 mL·h–1. Subsequent high-temperature
pyrolysis facilitated the conversion of organic paraffin/MK nanofibers
into SiO2 nanofibers with controllable pores structure.
Porous SiO2 nanofiber sponges fabricated using the microemulsion
SBS technique exhibit distinctive lightweight and thermal insulation
properties [0.037 W·(m·K)−1]. These properties
promise to facilitate massive spinning of high-performance inorganic
fiber sponges for applications in high-temperature thermal management.