Fabrication and Thermal Insulation Characterization of Melt-Blown Polypropylene/Silica Aerogel Nonwoven Fabrics

To develop heat insulation fabrics with lightweight, low volume and excellent thermal insulation properties, in this study, a binder-free polypropylene/silica aerogel nonwoven fabric with an area density of ${\sim}79.7g/m^2$ was fabricated via a facile melt-blowing process, and its structure, thermal conductivity and thermal insulation properties were investigated. For comparison, a polyester hollow fiber nonwoven having a similar area density of ${\sim}84.6g/m^2$ was prepared by needle-punching. Additionally, a series of composite nonwoven fabrics was prepared by layering the melt-blown polypropylene/silica aerogel nonwoven and the polyester hollow fiber nonwoven in various combinations, and their thermal insulation properties and thermal conductivity were analyzed. Scanning electron microscopic analyses revealed that 5 wt% silica aerogel added during the melt-blown process was adhered well to polypropylene fiber surfaces of the nonwoven fabric. As a result, the melt-blown polypropylene/silica aerogel nonwoven fabric exhibited a low thermal conductivity of $43mW/m{\cdot}K$ and relatively high level of thermal insulation performance, although its thickness (~1.5 mm) was lower than that (~2.2 mm) of needle-punched polyester hollow fiber nonwoven with a similar area density. The thermal conductivity was lowered and thermal insulation performance was improved, as the melt-blown polypropylene/silica aerogel nonwoven fabric was layered. It was also found that increasing the number of melt-blown polypropylene/silica aerogel nonwoven fabric layers in the composite nonwoven fabrics layered in various combinations decreased the thermal conductivity and improved the thermal insulating properties.

멜트블로운 폴리프로필렌/실리카 에어로겔 부직포의 제조와 단열 특성 분석