A Study on Thermal Insulation Performance of Electrospun Fiber Mat Laden with Nano/Micro Particles

Abstract

As the worldwide interest is focusing on the energy efficiency, the<br/> insulation material and techniques which can reduce energy loss<br/> become rising. One of the effective method is using super insulation<br/> material.<br/> Super insulation material is an insulation material whose thermal<br/> conductivity is less than the air`s thermal conductivity (26mw/m∙K).<br/> The aerogel panel and vacuum insulation panel are the most popular<br/> super insulation material. Both materials have low thermal<br/> conductivity, but they are too expensive and the manufacturing<br/> process is complicate. Also the mechanical strength of materials is<br/> bad for in daily life. To substitute the existing super insulation<br/> material, we invested the new method for super insulation material<br/> and manufacturing process.<br/> ii<br/> New material is made with electrospinning method which can make<br/> micro-nano fiber with polymer. Using this polymer fiber as a bonding<br/> material, we tried to make micro-nano particle based super<br/> insulation material. The particles were glass hollow beads and silica<br/> aerogel. Both particles have low density and thermal conductivity, so<br/> they are used in many areas for insulation. The thermal conductivity<br/> of made with the glass hollow bead was about 31 mw/m∙K, but the<br/> silica aerogel had 22 mw/m∙K thermal conductivity.and, we tried<br/> thinner fiber which made with NaCl, and the fiber mat without<br/> particles had the 31 mw/m∙K.<br/> As the new super insulation material is made with polymer, so it is<br/> easy to burn. Therefore, the fire retardant used to protect the fibers<br/> from the flame. The thermal conductivity of the film was influenced<br/> little but when the fiber had the pores on the surface, the thermal<br/> conductivity was decreased than before. Also the resultant of TGA<br/> was increased.<br/> The mechanical property was tested with tensile stress. As the mat<br/> was made with fibers, so the all-round samples` tensile stress was<br/> pretty low. In the case of NaCl added the value was increased, on the<br/> other hand, when fire retardant added, the value was decreased<br/> drastically.<br/> Keywords : Electrospinning, micro-nano particle, Silica aerogel, PLA,<br/> Thermal conductivity, fire retardant