Core-sheath Electrospinning of Shea Butter and Cellulose Acetate to Enhance Heat Transfer in Protective Clothing

Abstract

Protective clothing for health workers requires heat transfer in hot and humid environments. To study the thermal conduction of phase-change materials and protect them from leakage, we selected skin-friendly shea-butter due to its suitable melting temperature, and the electrospinning processibility of biocompatible cellulose acetate. The shea-butter as a phase-change material was encapsulated in electrospun cellulose acetate fibres within a core/sheath structure, which was stabilised by two concentric Taylor cones during coaxial electrospinning. Transmission and scanning electron microscopy revealed a blood-in-tube vessel-like morphology. Next, differential scanning calorimetry and thermogravimetric analyses confirmed the heat capacity of shea-butter (latent heat of fusion: 42.73 J/g; thermal conductivity: 1.407 W/m∙K). The flow rate of the core was proportional to the heat capacity of the shea-butter/cellulose acetate fibres. This was consistent with the finding that the electrospun fibres of the highest-ratio shea-butter (16.19%) had the highest thermal conductivity (0.421 J/g∙K). The shea-butter:cellulose acetate ratio was approximately 15:80. The efficacy of heat transfer for the core/sheath fibres in human clothing was assessed by measuring skin temperatures at 13 sites in six males aged 25 to 35 under two conditions: wearing a mask and hood with attached cellulose acetate fibres in the presence and absence of shea-butter. The mean difference in skin temperatures (0.5 ℃) between the two conditions was significant. Coaxial electrospinning of shea-butter/cellulose acetate fibres is therefore promising for protective clothing with efficient heat-transfer in the use of a large area.

Electrospinning of Poly (Acrylamide), Poly (Acrylic Acid) and Poly (Vinyl Alcohol) Nanofibers: Characterization and Optimization Study on the Effect of Different Parameters on Mean Diameter Using Taguchi Design of Experiment Method

“…Electrospinning has received increasing attention in the scientific community and industry over the past two decades, and is now seen as a critical research and commercial initiative with global economic benefits [ 1 ]. Nanocatalysis [ 2 ], tissue scaffolds [ 3 ], protective clothing [ 4 ], optical electronics [ 5 ], filtration [ 6 ], composites [ 7 ], energy storage [ 8 ] and sound absorption [ 9 ] are some of the applications of electrospun fiber mats. The electrospinning process is relatively simple.…”