Abstract
During the last decade, proofs have been given to the theoretical anticipation in that organic materials, viz.linear polymers, can be as strong as metals and inorganic materials if molecules are arranged parallel in a highly crystalline state. They include highly oriented fibres of aromatic polyamides and polyethylene, the whisker-type single-crystal of polyoxymethylene, etc. which enjoys the Young's modulus of >100 GPa. In this article, discussion is made firstly on the theoretical Young's modulus of polymers with respect to their conformation and secondly on the super-molecular structure emphasizing the importance of the latter for the bulk properties. Then, various approaches to the development of high-strength materials are reviewed with reference to the recent progress, covering the su-per-drawing of flexible polymers, the liquid-crystal spinning of aromatic polymers, the direct synthesis of polymer crystals from monomers, etc.
