抄録
Photoreactive multilayer films were prepared using long-chain alkyl diesters of p-phenylenediacrylic acid (p-PDA) such as p-PDA di-n-dodecyl ester and p-PDA di-n-tetradecyl ester. In spite of the absence of hydrophilic groups in these molecules, they formed stable monolayers on the water surface when mixed with arachidic acid. Surface pressure-area isotherms for mixed monolayers from these esters and arachidic acid showed the presence of a condensed phase and these monolayers could be transferred onto a substrate with Y-type deposition. The UV spectra of mixed multilayer films showed blue shift of absorption peak compared with that in solution. This indicates side by side molecular arrangement in these films. The linear relationship between absorbance and the number of layers supports the successful formation of multilayer films. Photoreaction of multilayer films occurred by cycloaddition of double bonds at initial stage and then a vinyl-type polymerization yielding polymers via oligomers. Irradiation of a m nolayer formed at water/air interface caused a monolayer to shrink resulting the formation of oligomers. In the crystalline state, photopolymerization proceeded topochemically forming cyclobutane rings in the main chain of polymers. The photochemical behaviour in these differentstates was discussed with reference to the molecular arrangement.
