Green
and sustainable photothermal fibers are gaining significant
attention for their role as high-performance thermal insulators in
personal thermal management applications. Conventional photothermal
fibers, such as carbon and zirconium carbide, are limited by their
black or dark gray appearance, which restricts their aesthetics and
fashion in textile design. To address this limitation, the present
study employs eco-friendly poly(lactic acid) (PLA) as the biopolymer
matrix and integrates cesium tungsten bronze (Cs
x
WO3), known for its excellent visible light transmittance
and significant near-infrared shielding capabilities, as the functional
component for photothermal conversion. Leveraging melt spinning technology,
this research explores for producing PLA fibers with high photothermal
conversion efficiency and dyeability. The impacts of the Cs
x
WO3 content on the rheological behavior,
crystallization, mechanical characteristics, dyeability, and photothermal
conversion performance of PLA were explored with the goal of providing
a scientific foundation for the development of color-diversified photothermal
conversion fibers. The findings show that incorporating Cs
x
WO3 at levels below 0.8 wt % does not
compromise the thermal stability of the PLA melt. Moreover, the addition
of Cs
x
WO3 notably promotes
the perfection of the PLA crystalline structure, which is beneficial
for maintaining the excellent mechanical properties of the PLA/Cs
x
WO3 fibers. The fibers exhibit
a tensile tenacity of about 4.3 cN/dtex and an elongation at break
of around 26%, aligning with the performance criteria for modern textile
processing. Additionally, the PLA/Cs
x
WO3 fibers demonstrate remarkable photothermal conversion capabilities.
At a Cs
x
WO3 concentration of
0.4 wt %, the fabric temperature increases by 20 °C under an
irradiance of 600 W/m2 after a mere 10 min of irradiation,
surpassing the temperature rise of the pure PLA fabric by 9.9 °C.
The dyeing performance of these fibers rivals that of pure PLA, enabling
a wide range of vibrant color applications.