IMPROVED THERMAL-RADIATION EXTINCTION IN METAL-COATED POLYPROPYLENE MICROFIBERS

If polypropylen microfibers with 2-3 mum diameters are coated with aluminum the infrared extinction increases by a factor of 20 as compared to the non-coated fibers. This has been shown by Mie scattering calculations and infrared optical transmission and reflection measurements using an integrating sphere. Large infrared extinction is important for the reduction of thermal radiative heat transfer in low density insulations. Insulation systems with Al-coated polypropylen microfiber fleeces can be expected to provide the same excellent insulation performance as natural downs.