The polymer composites developed in the present investigation are expected to have adequate potential for a wide variety of applications, particularly in microelectronic industries. With elevated mechanical properties like tensile strength, flexural strength, compressive strength and hardness also with enhanced thermal conductivity, improved glass transition temperature, reduced thermal expansion coefficient and modified dielectric characteristics, the polyester-based composites with appropriate proportions of fillers can be used in microelectronic applications like electronic packaging, encapsulations, printed circuit board substrates etc.