Characterization of Thermal Conductivity of Cellulose Acetate/Nano-SiO2 Electrospun Nanofiber Composites for Energy-Saving Using an Oxygen-Enriched Method

Abstract

Herein, the SiO₂ nanoparticles were applied to decrease the thermal conductivity of cellulose acetate (CA) nanofibers via electrospinning and the oxygen-enriched method. Hence, solutions of CA and CA/SiO₂ were made by acetone/dimethylacetamide (2 : 1) with oxygen enriching and Helium gas. The nanofiber’s morphology and chemical structures were studied by SEM and FTIR, respectively. Finally, the media’s thermal conductivities were calculated using the two-plate Togmeter device test method based on BS 4745:2005, and the media’s tensile strength features were evaluated under the ASTM D638-10 standard. According to SEM images, SiO₂ nanoparticles incredibly covered the whole surfaces of CA nanofibers in the CA/SiO₂ medium in a cloud shape. FTIR vibration spectrums confirmed the siloxane bands vibrated at 475/75 cm^–1 in the CA/SiO₂ mat. Moreover, the thermal conductivity of the CA and CA/SiO₂ sheets were 0.1 W/(m K) with 0.225 ± 0.005 mm thickness and 0.044 W/(m K) with 0.461 ± 2.88 mm thickness, respectively. Additionally, the CA medium had 0.5 ± 0.28 MPa tensile stress at 2.57 ± 1.25% tensile strain and the CA/SiO₂ membrane had 0.561 ± 0.057 MPa at 1.81 ± 0.939%. Hence, the CA/SiO₂ nanocomposite medium has a super low thermal conductivity with good mechanical properties. Therefore, the characterization of the thermal conductivity of cellulose Acetate/nano-SiO₂ electrospun nanofiber composites for energy-saving, using an Oxygen-enriched method was completely successful.