Concept and Overview of Rigid Rod Molecular Composites

Abstract

Recently, the concept of rigid rod molecular composites, originally demonstrated in the Air Force Materials Laboratory, has attracted wide spread attention in the global research community in the hope of creating a new generation of materials for structural and electronic applications in extreme environments. As originally conceived, a molecular composite is a homogeneous, synergistic composite of molecularly dispersed rigid rod polymer molecules (single molecules or small bundles of molecules with a lateral dimension of less than 50 Å) with high aspect ratios in a matrix material. The enhanced and desirable properties, such as superior chemical and environmental resistance, enhanced thermal and thermoxidative stability, toughness, and dimensional stability, resulting from the synergism between the reinforcing rigid rods and the matrix can only be realized in a true molecular composite. Without the development of true rigid rod molecular composite technology, the fundamental detrimental interfacial problems (adhesion, different thermal expansion coefficients, etc.) encountered in conventional fiber composites can not be averted. A truly revolutionary material technology can be developed only if one adheres to the original concept.