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Assembly of poly(acrylic acid) (PAAc) gel particles with DNA–ethidium bromide (EtBr) complexes was synthesized and the pH-sensitivity was evaluated for application in optical-sensor devices. The swelling ratio of the assembly was regularly changed with pH and the response speed of the assembly was approximately the same as the gel particles. The great increase in pH-sensitivity of the assembly was assumed to be induced by the porous structure. The fluorescence intensity was changed corresponding to the volume alteration of the assembly. The assembly could quickly detect the pH in the surrounding as an optical-signal.

Poly(acrylic acid) (PAAc) gel particles with DNA–ethidium bromide (EtBr) was synthesized and pH-sensitivity and fluorescence property were evaluated for applying to optical micro-pH sensor. Swelling ratio of PAAc gel particles with DNA–EtBr complexes were regularly changed with pH and the gel particle responded to pH for about 60 s. Furthermore, fluorescence intensity of PAAc gel particles with DNA–EtBr complexes were detected with high-sensitivity and changed in response to pH as shown in figure (The left shows the gel particles in pH 2.1 and the right shows in pH 11).

A DNA-lipid complex, where cationic surfactants are bonded to DNA, was synthesized and its optical property was examined by doping rare-earth chelates. The DNA lipid complex films to which several kinds of rare-earth chelates were doped were prepared, and their fluorescence quantum yields were examined. A 2 to 10-fold increase in quantum yield was observed as compared with conventional PMMA similarly doped. The improvement of the fluorescence quantum yield indicates that the use of DNA is promising in the development of new optical functional materials.

An ionizable thin film with gradient network size in direction of thickness was prepared using 10-undecenoic acid(UA) by plasma polymerization. Gradient structure in the network size was estimated by values of relative diffusion coefficient of ferocian ions through the film. The obtained film was found to show chemomechanical behavior. The film bent in alkaline solution due to anisotropic swelling in direction of thickness and recovered to the original shape in acid solution.

Studies on the interaction between polycations carrying charges on the chain backbone [x,y-ionene bromides (x = 3, 6, 12; y = 3, 4, 6, 12)] and anionic surfactants (sodium alkyl sulfates and sodium alkanesulfonates) have been made in water. It was found that there are two categories of surfactant binding: one is the formation of insoluble complex with one-to-one composition and the other is that of soluble complex with nonstoichiometric composition. Some of these complexes have ordered structure on a molecular and a supramolecular level, wherein the charge density and the alkyl size separating the charges on the chain backbone play an important role. The mechanism and process of the complex formation have been discussed.

Shape memory polymers were prepared by copolymerizing stearyl acrylate and methyl acrylate. The principle of this shape memory effect is based on reversible order-disorder transition of the crystalline aggregates of stearyl moieties. A specific feature of this type of shape memory copolymer is that the transition temperature at which the polymer abruptly become soft and deforms can be controlled by changing the monomer composition, which enables one to adjust the shape memory effect at the desired temperature. Mechanism and process of the shape memory behaviors are discussed

チタニウムテトライソプロポキシド(TIPP)を出発物質として高い導電率を示すチタソ含有プラズマ重合膜を合成し,導電率の変化に基づくガスセソサーとしての機能につい七調べた。その結果,プラズマ重合によって合成したチタン含有有機薄膜は150～300℃ の温度範囲で,メタノール,エタノール,1-ブタノール,t-ブチルアルコール,アセトンなど,酸素と反応する有機可燃性ガスが存在すると,膜の漕電率が速やかに増大する現象を見いだし,これを利用すると導電率の増加により有機可燃性ガスを定量的に測定できることが明らかとなった。このセンサーの応答機構は膜表面の酸素の吸脱着により,導電率が変化するためであると考えられ,その機構について議論した。

Aniline was electrochemically polymerized in aqueous electrolyte containing polymer electrolytes which have the sulfonate group. The very small amount of polymer electrolytes were selectively incorporated into the polyaniline matrix. The added polymer electrolytes accelerate the film growth rate. The surface morphology of the films was also changed dramatically with the addition of the polymer electrolytes.

The effect of molecular weight on ion selective electrochemical polymerization was investigated. The very small amount of polymer electrolyte added to the electrolyte affects the polymerization rate of aniline. The polyaniline film grows faster and the selectivity is increased when the higher molecular weight of polystyrenesulfonate is used. ESCA spectra revealed the strong interaction of the polystyrenesulfonate with the polyaniline nitrogen atom, which depends on the molecular weight.

Adsorption phenomena of polystyrenesulfonate onto polyaniline were investigated be ESCA. The polymer electrolyte was selectively adsorbed on the polyaniline surface. The dopant at the outermost surface of the polyaniline was completely exchanged by the polystyrenesulfonate depending on the oxidation state of the conducting polymer. The adsorbed polystyrenesulfonate was hardly exchanged by the perchlorate anion and has a strong interaction to the nitrogen atom of the polyaniline.

Polymeric thin films were prepared from gaseous titanium tetraisopropoxide by low‐temperature plasma polymerization. The films exhibited n‐type semiconductor properties and showed conductivities in the range between 10−8–102 s/cm. High photocurrent under irradiation of 30 mW/cm2 of visible light was observed which exceeded the value found for plasma‐polymerized copper acetylacetonate thin films by nearly three orders of magnitude. From x‐ray photoelectron spectroscopy analysis, it was found that the films largely consist of metallic and organic layers corresponding to TiOx(0

Recent research results on DNA-lipid complexes have shown various attractive features on E/O or O/E devices, optical memories, switches and sensors by intercalating optical dye into DNA double helix. Physical properties of DN-lipid complexes are greatly dependent on kinds of lipids and chiral lipids from α-amino acids were prepared so that self-assembled structure of DNA molecules was organized. DNA-L-alanine-derived lipid formed a self-assembled film with a liquid crystalline structure, which showed a less water absorption. DNA devices absorbed water under high humidity which led to decreases of optical functions. However, it was possible to encapsulate the DNA-lipid complexes into sol-gel materials so that a water permeation was prevented by glass to stabilize and to keep the optical functions for a long time.

DNA-CTMA solutions in ethanol doped by various azobenzene compounds were prepared and their absorbance transition by irradiate UV were measured. It was found that trans-cis transition took place in the cases of doped azobenzene and azobenzene-4,4'-dicarboxylic acid diethyl ester(ADCDE). It did not depend for the speed of trans-cis transition of solution which doped both azobenzene and ADCDE to DNA-CTMA with those amount of doping. To the next DNA-CTMA films doped by azobenzene and ADCDE were prepared and their absorbance transition by irradiate UV were measured. Consequently, trans-cis transition took place only by only the films doped azobenzene and was not transferred by the films doped ADCDE. It was found that trans-cis transition of DNA-CTMA films doped by azobenzene (100:1) was faster than PMMA films doped same amount of azobenzene. It is considered that because azobenzene molecules were isolated by intercalation to DNA and the spatial flexibility of azobenzene molecules became large, the speed of trans-cis transition of azobenzene became early compared with the case where it doped to PMMA.

DNA fibers were prepared by melt spinning method from DNA-CTMA powder. A hemicyanine dye, trans-4-{4-(dibutylamino)-styryl}-1-methylpyridinium iodide (DBASMPI) doped DNA-CTMA fiber with core diameter of 1 mm and dye concentration of 3.6 wt% was obtained by soaking it in an aqueous dye solution. Laser (532 nm) pumped amplified spontaneous emission (ASE) at 610 nm was observed in the dye-doped DNA-CTMA fiber. The ASE occurred at energy density 50 mW. The amplification of optical signals at 607 nm wavelength was confirmed. The results from ASE emphasize that DBASMPI doped DNA-CTMA fiber is appealing as a good candidate for optical amplifiers and superfluorescence sources in a variety of communication and sensor applications.

We observed optical properties of organic fluorescence materials doped DNA-CTMA and PMMA. The quantum yield in DNA-CTMA was higher than in PMMA. Amplified spontaneous emission properties of dye-doped DNA-CTMA film at ambient temperature were investigated. The narrowing of line shape and amplified spontaneous emission dependence occur at the same intensity indicates that both effects are the results of light amplification. We discussed the lasing capability by interacting DNA-CTMA.

We observed optical properties from several kinds of Eu-chelates doped DNA-CTMA and PMMA films. The lifetime in DNA-CTMA was longer than in PMMA, and the quantum yield in DNA-CTMA was also higher than in PMMA. Among them, we calculated each cross section because we compared laser properties of Eu-chelates by interacting DNA-CTMA with PMMA. We will discuss the lasing capability by interacting DNA-CTMA.

A DNA-CTMA optical fiber was prepared by melt-spinning method for the first time. A hemicyanine dye, trans-4-(4-dibutylamino)-styryl)-1-methylpyridinium iodide (DBASMPI) doped DNA-CTMA fiber with core diameter of 1 mm and dye concentration of 3.6 wt% was obtained by soaking it in an aqueous dye solution. Laser (532 nm) pumped amplified spontaneous emission (ASE) at 610 nm was observed in the dye-doped DNA-CTMA fiber. The ASE occured at energy density 50 mW. The results from ASE emphasize that DBASMPI doped DNA-CTMA fiber is appealing as a good candidate for optical amplifiers and superfluorescence sources in a variety of communication and sensor applications.

This paper formulates and solves the inverse dynamics problem of deformable robots made entirely of electro-active polymer gel. One of the primary difficulties with deformable robots is that they have conceptually infinite degrees of freedom. We solve this problem through the selection of an essential point to generate a desired motion. The problem is then reduced to trajectory control of a point on the robot. We have proposed dynamic models of electro-active polymers system and derived a variety of motions by applying either spatially or time varying electric fields. However, the motion control problem has not yet been investigated. We show a procedure to realize an inversion (turning over) motion of a starfish-shaped gel robots by applying both spatially varying and time alternating electric fields. This work takes the first step towards motion control of deformable robots.

This paper proposes a model for predicting the dynamic motions of elastic robots made entirely of electro-active polymer gel. The requirement is that both the active and passive deformations be described simultaneously. Active deformations arise from a generated stress, while passive deformations are due to external forces, such as gravity and friction. We represent both in the same framework, considering them as the result of either electrochemical or mechanical interaction between the gel robot and the environment. We evaluated the model by comparing the results obtained through simulations and experiments using prototype gel robots. One experiment involved hitting an external object, and the other involved bending while resting upon a surface. We present an overview of the model, with a discussion of the experimental results and future work.

A polythiophene-doped polymethylacrylate which have absorbance in visible region was synthesized by plasma polymerization, and its fluorescence spectra was studied. The absorption peak was 440nm, the fluorescence emission of spectra was 570nm. The intensity of the fluorescence emission of the polymer was higher than that of the polymer synthesized by radical polymerization. It is reasonable to suppose that chemical reaction of plasma polymerization was mild compared with radical polymerization.

The polymeric cross-linked hydrogel doped with dye 4- nitroaniline was prepared. The nonlinear optical properties of this material has been studied. The optical storage effects and the dynamic lens effects in this dye doped hydrogel under laser radiation have been observed. It is reasonable to show that this dye doped polymer get will find some applications in optical signal processing.