Influence of Punch Density and Fiber Blends on Thermal Conductivity on Nonwoven

Abstract

One of the major applications for nonwoven fibrous system is as thermal insulation materials. Many factors may affect thermal properties. This research attempts to study the effects of punch density and fiber blends on heat transfer in nonwoven. For this purpose the samples, whose properties are analyzed by using static methods for measuring their thermal conductivity, were constructed in blends of polyester with polypropylene. The blend ratios are 100% PET, 80/20, 60/40, 40/60, 20/80, and 100% PP. Six samples were produced from each blend by changing the primary needle punch density to115, 135, 155, 175, and 195 punches per cm2. The secondary needle punch density was held constant at 120 punches per cm2. The temperature of the hot plate, i.e. the applied temperature, was 40°C. Experimental results show that with increasing punch density and pressure, heat transfer decreases. Moreover, the results indicate that the blending of fiber types causes a reduction in fabric heat transfer.