Egg shell powder added rigid polyurethane foams: The investigation of their thermal conductivity, compressive strength and fire behaviors [Yumurta Kabuğu Tozu Katkılanmış Sert Poliüretan Köpükler: Termal İletkenlik, Basma Mukavemeti ve Yanma Davranışlarının İncelenmesi]

Abstract

In this study, rigid polyurethane foam composites (SPKK's) containing egg shell powder (YKT) with different ratio were synthesized. YKT was characterized by using X-ray difractometer (XRD), X-ray fluorescence spectrometer (XRF) and Fourier transform infrared spectrophotometer (FTIR). The surface morphology, closed cell ratio and density, thermal conductivity, and compressive strength of the foams were examined/measured/determined by scanning electron microscope (SEM), gas displacement pycnometer, heat flow meter, and universal test machine, respectively. Limiting oxygen index (LOI) and cone calorimetry were used to evaluate the fire performance of the foams. The effects of YKT amount on the average cell size, closed cell ratio, thermal conductivity, density, compressive strength and fire behavior of the foams were investigated. When compared with rigid polyurethane foam without additive (SPK), while the mean cell size and thermal conductivity values of the obtained SPKKs showed a decrease, closed cell content and density values of them increased. With SPKK containing 7% YKT, the thermal conductivity was reduced by about 8%. The compressive strength values for the SPKKs at low YKT ratios were higher than that of SPK, and the strength decreased with the further increase in the amount of additives. LOI values were improved slightly with the addition of YKT. When YKT loading was %25, the LOI value of SPKK, which is %19.7 for SPK, increased to %20.4. Cone calorimetry results showed that fire performance index values of composites are better than that of SPK