Abstract:
The free volume is related to a lot of physical properties of polymers. For instance, it is the thermal expansion, the gas permeation, the viscosity and the mechanical properties, etc. However, the free volume is conceptually defined in many cases by each theory and the strict meaning is different according to the theory even if a word same, free volume is used. Therefore, it complicates the free volume. Since the free volume relates to a lot of physical properties, we should clarify the relationship between each theory and use it to explain the physical properties of polymer. 
Here, some ideas of a free volume are shown, and the relation between a measurement of the free volume hole size by the positron annihilation lifetime spectroscopy and its various physical properties is described. For instance, the contribution of free volume concerning the volume change of polymer, the relationship between the free volume and gas barrier properties, and the physical properties of polymer thin film explained by the free volume behavior

Affiliation:
Department of Chemistry and Materials Science,
Graduate School of Science and Engineering,
Tokyo Institute of Technology
Ookayama, Meguro-ku, Tokyo 152-8552, Japan
Tel& Fax:+81-3-5734-2423
E-mail: tougizawa@op.titech.ac.jp
Website:  http://www.op.titech.ac.jp/lab/ougizawa/index.html
Education:
BS (1983), MS (1985) and Ph.D (1987) in Tokyo Institute of Technology
Professional Appointments:
1987-1989Visiting Scientist, Central Research and Development, Experimental Station, DuPont (U.S.A.)
1989-1993 Researcher, Research Institute for Polymers and Textiles (Japan)
1993-1994 Senior Researcher, National Institute of Materials and Chemical Research (Japan)
1994-2011 Associate Professor, Tokyo Institute of Technology
2011-present Professor, Tokyo Institute of Technology