and added to the mixture and stirred for 2 mins at 80?C by the mechanical stirrer under the purge of N2. The synthesized PU elastomer samples were immediately casted in the iron moulds to form sheet and disc shape for testing. Then , the moulded samples were cured in an oven at various tempartures (90,120,130 ?C). The coating samples were also prepared by applying the synthetised PU elastomers on the steel surface which were inserted in silicon mould. Attenuated Total Reflectance fourier transform infrared spectroscopy (ATR-FTIR) and swelling ratio measurements of the cured samples showed that a reaction occurred between isocyanate end groups of pre polymer and hydroxyl groups of O-MMT (closite 30B). Also it was shown that adding nano particles to polyurethane matrix reduced cross link density. X-ray diffraction pattern showed that in 1 and 3 wt% nano particles polyurethane chains were penetrated in the O-MMT layers and was formed intercalated structure but, in 0.5 wt% nano particles the semi exfoliated structure was obtained. Tensile results indicated that elongation at break of the samples containing nano particles increased 2-3 times more than the refrence sample. by adding 0.5wt% of nano particles to the polymeric matrix ultimate tensile strength (UTS) of the samples was 2 times higher than the refrence sample. More then 1wt% organic modified montmorillonite to the polymer matrix, remarkable decrease in the ultimate tensile strength was observed. Therefore, the samples containing 0.5 wt% nano particles showed the highest ultimate tensile strength. Hardness test measurment indicated that hardness of the samples was decrased by increasing the nano particles concentration in the polymer matrix. Abrasion resistance measurments showed 16 Vol% decrease in the amount of the sample?s voulumes for CPU05 sample compared with the reference sample. Increase in the nano particle concentration led to decrease in the abrasion resistance of the samples. Adhesion test data showed that the abrasion resistance of the samples containing nano particles (CPU05,CPU1,CPU3 and CPU5). Adhesion strength of the CPU1 and CPU3 samples was lower than the CPU05 sample but, the CPU5 sample showed the lowest adhesion strength which even is lower than the refrence sample. Adhesion strength of the CPU05 was 2.2 times more than the refrence sample. The presence of nano particles in the samples decreased their cross link density. Thermogravimetric analysis (TGA) results showed that degration starting temperatures of the samples containing 1 and 3 wt% of nano particle , 47 and 40?C respectively. Weight precent of the residul nano particles (CPU05,CPU1 and CPU3) was increased compared to sample without nano particle. .
