Nano alumina (Al2O3) was prepared by gel combustion method. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to characterize the nano alumina. The results show that the prepared alumina was in nano meter range. It was added as reinforcing filler in styrene butadiene rubber(SBR). Mechanical property improvements were achieved by the addition of low amounts of nano alumina along with maleic anhydride as compatabilizer. Method of preparing an emulsfier useable in emulsion polymerization processes, comprising the steps of subjecting rosin, polyunsaturated fatty acid or mixture thereof to disproportionation reaction, in the presence of a catalyst of iron iodide, and then neutralizing with alkali, and use of such emulsifier in emulsion polymerization processes.