ABSTRACT The very fast developments in technology of composite materials have lead to newer and wider applications of such promising materials. Composite materials offer a number of potential advantages in the aerospace field, particularly in safety-critical structures such as primary and secondary aircraft components. In order to improve the various mechanical properties and to reduce the cost of composites several methods have been adopted. Modifications or blending of resins is one of these avenues. The polymer blends are formed by combining two or more polymers. In the present project the epoxy is blended with unsaturated polyester in different proportions. The resulting polymers blend systems often exhibit properties that are superior to any one of the component polymer alone.