English Abstract
High Functionability of Biodegradable Biomass Plastic Fibers
Tadahisa IWATA*1,
Toshihisa TANAKA*2
*1Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
*2Faculty of Tex-tile Science and Technology, Shinshu University, Tokida, Ueda-shi, Nagano, Japan Nippon Gomu Kyokaishi,(2008),81(9),358-363 General Review in Japanese

Poly[(R)-3-hydroxybutyrate] and its copolymers are accumulated by a wide variety of micro-organisms as intracellu-lar carbon and energy materials, and are extensively studied as biodegradable and biocompatible plastics. However,these microbial polyesters have not been recognized as practical because of their stiffness and brittleness.
Recently, we succeeded to obtain strong fibers with a tensile strength over 1.0 GPa by two kinds of new drawing techniques. The structure of strong fibers was analyzed by micro-beam X-ray diffraction and X-ray micro-tomography in synchrotron radiation. Furthermore, the strong fibers were completely degraded in natural river water or by extracellular polyhy-droxybutyrate depolymerases. In this paper, the processing, mechanical properties, molecular and highly-ordered struc-tures, and biodegradability of strong fibers are presented.

Biodegradable Biomass Plastics, Polyhydroxyalkanoate, Strong Fibers, Synchrotron Radiation, Micro-beam X-ray Diffraction, X-ray Micro-tomography, Enzymatic Degradation