In recent years, a growing number of engineering applications of light weight and energy efficient plastics can be found in high quality parts vital to the func tioning of entire equipments and structures. Improved mechanical properties, especially balance of stiffness and toughness, are among the most frequently desired features of the new materials. In addition, reduced flammability is con sidered the single most important requirement for further expansion of plastics into large volume and demanding markets such as construction and mass trans port. Production of power cables also requires flame retardant cable jacketing plastics to replace or at least to reduce consumption of environmentally unsound PVC. The two principal ways to achieve the goals mentioned above include the development of completely new thermoplastic polymers and various modifica tions of the existing ones.Development and commercialization of a new ther moplastic require mobilization of large human and financial resources, the lat ter being within the range from $100 million to $10 billion, in comparison to $100 thousand to $10 million needed to develop and commercialize polymeric mate rial with prescribed end use properties using physical or chemical modification of an existing plastic. In addition, the various markets utilizing thermoplastics demand large flexibility in material properties with only moderate volumes, at the best.