Mitsuru Tanahashi

Development of Fabrication Methods of Filler/Polymer Nanocomposites: With Focus on Simple Melt-Compounding- Based Approach without Surface Modification of Nanofillers

Many attempts have been made to fabricate various types of inorganic nanoparticle-filled polymers (filler/polymer nanocomposites) by a mechanical or chemical approach. However, these approaches require modification of the nanofiller surfaces and/or complicated polymerization reactions, making them unsuitable for industrial-scale production of the nanocomposites. The author and coworkers have proposed a simple melt-compounding method for the fabrication of silica/polymer nanocomposites, wherein silica nanoparticles without surface modification were dispersed through the breakdown of loose agglomerates of colloidal nano-silica spheres in a kneaded polymer melt. This review aims to discuss experimental techniques of the proposed method and its advantages over other developed methods.

Self-repairing mechanism of plastics

Abstract The protection mechanism of a living body and man-made materials can be classified into two categories. One is a passive protection by which the body and materials are guarded by simple chemicals such as light absorbents, and the other is anactive protection that repairs with metabolic reactions the internal injury suffered by many kinds of deterioration factors from the outside. Polyphenylene–ether was selected as a man-made material in which the metabolic reaction can be achieved in the atmosphere (21% of oxygen) and at room temperature (20–40 8C). The polymer introduces oxygen as an energy source,transports it with copper-complex and repairs the scission point of the chain. Such active protections were attempted for several polymers and some advantages and problems were elucidated. In this paper, the mechanisms of active protections in some plastics are reviewed and are also compared with protection systems of a living body, which provide us with very useful information on the development of advanced materials.

Advances in nature-guided materials processing

Abstract The center of excellence (COE) titled ‘The Creation of Nature-Guided Materials Processing’ has been established in Nagoya University as the 21st Century COE Program supported by Ministry of Education, Culture, Sports, Science and Technology. In the Nature COE, various activities on the education and research are being performed through learning the laws of nature, namely, methods of attaining ‘appearance of the maximum function under the minimum substance and energy consumption’, which the nature and living organisms have acquired through their evolution in long period. Together with such educational programs for PhD students as research incentive, oversea training, and external evaluation programs, an ‘Open-Cluster Program’ was originated for promoting researches proposed by research groups consisting of young researchers in and out of the university and also for fostering them. The researches are being advanced on materials used for living bodies, mimicking structures which nature or living bodies are forming, and producing materials by mimicking processes to form the structures observed in the nature or the living bodies. In this COE, these researches are conducted by four groups to extend the processes observed in the natural world to a new type of processing, that is, thoroughly examined and rationalized by plunging a scalpel of engineering and to establish a new academic field of materials science and engineering.