Research Director: Dr. Toyoki Kunitake
(Professor, Faculty of Engineering, Kyushu University)
Research Term: 1987-1992

Synthetic bilayer membranes are promising materials, since molecular design is easy and the molecular structure is diversified. A technology has been developed to manufacture new chemical products with structures precisely arranged and bonded at the molecular scale by combining the unique molecular structure of synthetic bilayer membranes with other materials.

Research Results

Molecular recognition and water-surface monomolecular membrane by complementary hydrogen bonding: Molecular recognition was studied using water-surface monomolecular membranes. The binding behavior of biochemically important water-soluble guests were examined.

Elucidation of molecular interaction by direct surface forces measurement: When the surface of mica was covered with a polymeric monolayer, surfaces separated by as much as 300nm from each other were attracted. The structural change and interaction of poly (methacylic acid) attached to the mica surface were elucidated.

Observation of molecular ordering and epitaxial polymerization with a scanning tunneling microscope (STM): Ring-opening polymerization of cyclic ether, lactone, and lactam as well as radical polymerization of vinylidine chloride were carried out in contact with a graphite surface.

Formation of ultrathin silica layers by a molecular template method:A multi-layer ultrathin membrane was produced in such a way that the starting material was introduced into a gap between the regularly arranged layers of cast films used as the mold, and hardened; the mold was then removed.

Film formation from ultrafine inorganic particles: Self-supporting multi-layer films were produced by applying the molecular template method to metal oxides, including TiO₂, Al₂O₃, SnO₂ and CeO₂.

Development of totally conjugated LB membrane: Various oligophenylene vinylene compounds were systematically synthesized. Various polymeric polar LB membranes were produced based on the results.

Multi-layer ultrathin polymeric membrane by a molecular template method: Various multi-layer polymeric membranes were successfully produced. For instance, a multi-layer polymeric film was produced by casting a water dispersion of the bis-acrylic monomer together with a bilayer membrane, making a two-dimensional crosslinking and removing the membrane mold.

Two-dimensional polymer network: A polymer-ion complex was produced from an anionic monomolecular membrane on water with cationic polyallylamine; it was transferred and crosslinked by heating.

Ultrathin films of silica-alumina, prepared by using bilayer films as molecular templates, have nanometer thickness, and wide applicabilities are conceivable.

Specific recognition of bioactive molecules, such as sugar and nucleic acid, is expected to have wide applicability as artifical receptor.