Some of surface properties are governed by thermal molecular motions of polymer chains at the interfacial region. Therefore, the polymer surface composed of both hydrophilic and hydrophobic graft chains will be expected to change its wettability reversibly with surrounding media In this study, we prepared the “chameleon-like surface”, which is sensitive and responds to the surrounding media As an approach to the chameleon-like surface, we prepared poly-L-lactide films grafted with poly (acrylamide) of a hydrophilic graft chain and subsequently with poly (2, 2, 2-trifluoroethyl methacrylate) of a hydrophobic graft chain. These modifications were carried out by plasma irradiation technique. Static contact angles of water for the grafted film which was immersed in ethylacetate and then dried in air was relatively high, whereas the grafted film immersed in water readily became wettable by water. This change was reversible in response to the change of the solvents. Contact angles were indeed varied with the kind of the immersion solvents, which are related to solubility of the grafted polymer chain. Probably, the chains of the fluorinated methacrylate polymer were tethered from the surface via solubilization and the surface coverage might determine the degree of the contact angles. Dynamic contact angles of the grafted film were measured with a Wilhelmy plate technique. The advancing contact angle measured at the high immersion rate dropped suddenly and remained constant at around 20 degree. In contrast, at relatively low immersion rates, both the advancing and receding contact angles remained constant. These results suggest that the chameleon-like surface property is determined by the reorientation and the reorganization of the grafted layers. We also found from XPS and AFM that the chameleon-like surface has a unique surface morphology and grafted chains were oriented and tethered to meet the surrounding environment

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Several years ago, we found that a new telechelic oligomer, which consists of alternating 3, 3-dimethyl-3-silapentane and N, N'-diethylethylenediamine units in the main chain (poly (silamine)), was obtained through an anionic polyaddition reaction between divinylsilanes and diamines in the presence of lithium catalyst. Due to the hydrophilic-hydrophobic repeating unit in the main chain, poly (silamine) shows unique phase transition properties in response to the degree of protonation of its amino groups in aqueous media : i) Its solubility in aqueous media drastically changes; ii) Poly (silamine) shows a strong interaction with several anions; and iii) Due to the interaction between protonated poly (silamine) and anions, the rubber elasticity of the poly (silamine) is drastically changed. Actually, the glass transition temperatures of the poly (silamine) can be varied from-85°C to + 80°C by the environmental conditions. If such a transition of single chain can be synchronized to the matrix, output signals should be tremendous. In this review, synthesis, characteristics and tethered chain construction of poly (silamine) are described.

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Few efforts have been made so far on the achievement of large stimulus-responsive deformations in highly organized polymer assemblies. The importance of such approach is of no doubt if one looks at the sophisticated activities in biological systems. This review article focuses to our recent studies on the organized photoresponsive polymer monolayers and related organized systems. Our investigation involves (1) the photo-driven deformation of “nano-scale” azobenzene containing monolayer, (2) information transfer to “meso-scale” polymer films, and (3) light-induced “micro-scale” mass transfer in spincast films. In all cases, the the photoisomerization process of azobenzene taking place in the organized assemblies is of essence to bring large and effective dynamic processes.

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