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Immunoglobulin G (IgG) has been modified by poly(N-isopropylacrylamide) (PIPAAm) to create a novel bioconjugate which exhibits reversible phase transition behavior at 32 degrees C in aqueous media. A terminal carboxyl group introduced into PIPAAm molecule by polymerization of IPAAm with 3-mercaptopropionic acid was used for conjugation to IgG via coupling reaction of activated ester with protein amino group. These conjugates exhibited rapid response to changes in solution temperature and significant phase separation above a critical solution temperature corresponding to that for the original PIPAAm. These conjugates bound to antigen quantitatively in aqueous system, and antigen-bound complex also demonstrated phase separation and precipitation above a critical temperature. Precipitate was reversibly redissolved in cold buffer. Though particular conjugate which includes 12 molecules of PIPAAm with 6,100 molecular weight suppressed more than 95% of Fc-dependent binding with protein A, it retained approximately 60% of original specific antigen binding activity. It was manifested that polymer content of conjugate was 20-30 wt% for the case of 6,100 molecular weight of PIPAAm to demonstrate specific antigen binding activity most effectively and to reduce Fc-dependent binding with protein A. IgG-PIPAAm conjugates were soluble in water and formed antigen-bound complex in homogeneous solution system below a critical temperature. These conjugates were separated from solution and other solutes corresponding to PIPAAm nature and scarcely bound to antigen above a critical temperature. It is revealed that temperature-responsive PIPAAm conjugated to biomolecule operated as a switching molecule. These phenomena are attractive for not only reversible bioreactors and protein separations but also carrier substrate to localize biomolecules such as drugs, peptides and hormones in a living body.

With an increasing demand for artificial organs which are utilized in contact with blood to substitute for various body functions such as circulation, the elimination of waste and gas exchange, biomaterials with reliable antithrombogenicity have been greatly needed. When in contact with blood, artificial surfaces generally induce platelet adhesion and subsequent activation, which can lead to thrombus formation accompanied by the formation of an insoluble fibrin network1. Therefore, one promising way for creating material surfaces with thromboresistant properties is the design of surfaces eliminating the activation process of adhering platelets2.

New ion conductive polymers were obtained by dissolving polycations into room temperature molten salt consisting of methyltriethylammonium chloride (MEAC1) and aluminium chloride (A1C13). These complexes formed viscoelastic solids when the polycation content was increased more than 4 unit mol%. The ionic conductivity of polycation complexes was in the range of 10-4-10-3 Scm-1 at room temperature and were affected by their composition, types of polycations, and counter anion species.

Primary culture of the chromaffin cells on polypyrrole-coated indium-tin oxide was performed and the influence of polypyrroles having some kinds of dopants on cell function was investigated. While the cells cultured on indium-tin oxide showed decrease of catecholamine release, those on polypyrrole-coated indium-tin oxide maintained the cell function of release of catecholamines. Furthermore, no influence of various dopants on the secretory function from the cultured cells was observed. To prepare polypyrrole on electrode as a cell-culture substrate was considered to be available for supporting the cell function.

We have synthesized carboxyl semitelechelic oligo(N-isopropylacrylamide) (OIPAAm) using radical telomerization with 3-mercaptopropionic acid. This telomerization is also effective for the synthesis of carboxyl semitelechelic co-oligomers of IPAAm with butyl methacrylate (BMA) as hydrophobic or N,N-dimethylacrylamide (DMAAm) as hydrophilic comonomers. All co-oligomers are highly water-soluble at lower temperatures and exhibit phase separation with increasing temperature. Pure OIPAAm exhibits a lower critical solution temperature (LCST) at 32 degrees C, and the LCST for co-oligomers can be controlled to increase over 32 degrees C with increasing DMAAm composition and to decrease below 32 degrees C with increasing BMA composition. OIPAAm was grafted to bovine serum albumin (BSA) and bovine plasma fibrinogen (BPF) by activated ester-amine coupling. These OIPAAm-biomolecule conjugates maintain their temperature responses, are soluble in cold water, and precipitate over a range of temperatures related to oligomer content. Conjugates could be selectively precipitated and independently separated from conjugate solution mixtures with increasing temperature. In this case, the number of OIPAAm molecules attached to a conjugate affects the aggregate sizes of precipitated conjugates in mixtures. Both conjugate mixture ratios and solution concentrations influence the contamination of oligo(IPAAm-co-DMAAm)-BSA conjugates in precipitated oligo(IPAAm-co-BMA)-BPF conjugates. Furthermore, precipitated conjugates separated using centrifugation and filtration redissolve in water and maintain their biofunctionality, indicating the potential of strategy in reversible bioreactors and protein separations.

Using 3-mercaptopropionic acid (MPA) as a chain-transfer agent, the radical oligomerization of N-isopropylacrylamie (IPAAm) was carried out with varying molar ratios of MPA to IPAAm and DMF. The molecular weight of oligo-IPAAm (OIPAAm) could be controlled by the ratio of MPA to IPAAm. The OIPAAm was confirmed to average one carboxyl end group per chain. All OIPAAms samples were highly water-soluble at lower temperatures and exhibited phase separation near 32 degrees C. The optical transmittance of the OIPAAms aqueous solutions changed drastically at 32 degrees C which was independent of OIPAAms molecular weight. In aqueous solutions of OIPAAm having concentrations higher than 1 wt% and molecular weight of 6100, the oligomers were precipitated and recovered in 85 wt% yield of their original content. Further, OIPAAm was grafted to atelo collagen by activated ester-amine coupling. The OIPAAm-collagen conjugates were able to dissolved in cold water and precipitated at 34 degrees C. Temperature-responsive OIPAAm-collagen conjugates are expected to maintain native collagen functionality in the solution state, react at lower temperatures, and be easily removed from the system with small temperature increases.

New ion conductive polymer complexes were formed by dissolving poly(1-butyl-4- vinylpyridinium) salts into room temperature molten salts consisting of 1-butylpyridinium salts and aluminium chloride. The viscoelastic films were fabricated from the molten salts added at least 10 mol % of the polypyridinium salts. The ionic conductivities of the polymer complexes were in the range of 10−3−10−4 Scm−1 at room temperature and were affected by their composition.

Langmuir-Blodgett films were fabricated from mixed monolayers containing stearic acid (SA) and various Head-to-Tail poly(3-alkylthiophene)s ( HT -PATs : alkyl = hexyl ( HT -PHT), decyl ( HT -PDT), octadecyl ( HT -PODT)). The HT -PATs could form stable monolayers on the air-water interface with stearic acid, and could be deposited onto solid substrates as Y-type films by vertical dipping method. The structure of HT -PATs/SA LB films were investigated by transmission and reflection-absorption FT-IR measurements. By comparison of transmission and reflection FT-IR spectra, the tilt angles of alkyl side-chains of HT -PATs could be estimated. These results shows that self-organized properties and molecular orientation of HT -PATs were affected by the length of alkyl-side chains. HT -PDT was found to form more planar conformation because of the optimized length of alkyl-side chains.

We fabricated electrostatic self-assembled thin films with poly(thiophene-3-acetic acid) (PTAA) as a polyanion and a positively-charged second-order NLO chromophore as a cation. UV-Vis, FT-IR, and second-harmonic generation (SHG) were measuredin orderto investigate the process of anion and cation adsorption andto understand the relationship between structure and optical properties of the ultra thin films. UV-Vis and FT-IR spectra of these films indicated that PTAA and the NLO chromophore formed a layer-by-layer structure. SHG measurements suggested that the NLO chromophores were noncentrosymmetrically aligned within the self-assembled films.

Chiral Langmuir-Blodgett (LB) films were fabricated from mixed monolayers containing regioregular poly(3-[2-((S)-2methylbutoxy) ethyl]thiophene) ( HT -P(S)MBET) and stearic acid (SA) with different molar ratios. The HT -P(S)MBET was an optically active polymer with the head-to-tail linkage of larger than 93 %. From the UV-Vis spectra and X-ray diffraction measurements, it was found that the HT -P(S)MBET in the LB film form a layered structure in which the main chains are oriented parallel to the plane of the substrate and exhibit a tendency to orient along the dipping direction. The in-plane conductivity of the HT -P(S)MBET/SALB film doped with SbCl 5 was 1.2S cm −1 . The observed value of the third-order nonlinear susceptibility at the exciton resonance peak was in the order of 10 −7 –10 −8 esu.

A structurally well-defined multilayer enzyme electrode comprised of a lipid-modified glucose oxidase and an electrically conductive poly(pyrrole) LB film for detecting glucose was fabricated by using the Langmuir-Blodgett technique. The voltammetric measurements of these electrodes revealed that the electrically conductive poly(pyrrole) layers could quantitatively detect the hydrogen peroxide produced by the modified enzyme layers. The amperometric anodic current (at 0.6 V vs. Ag/AgCl) of the electrode increased with increasing the glucose concentration. A linear response to glucose concentration was observed in the range of 15–100 mM with a detection limit of 5 mM.

New bisaxially coordinated phthalocyaninatoiron complexes were synthesized by melting azopyridines and phthalocyaninatoiron. Monolayers of azopyridine/phthalocyaninatoiron complexes were spread from their benzene solutions, and the π-A isotherms were measured. The multilayer thin films were fabricated by the Langmuir-Blodgett technique. The structure of the multilayer thin films was investigated by UV-Vis spectra, X-ray diffraction, and FT-IR measurements. These LB films are rendered electrically conductive by doping with strong oxidizing agents such as NOPF6, I2, and SbCl5.

Tetracationic cyclophanes and a [2]-catenane consisting of cyclobis(azopyridinium-p-phenylene) were synthesized via the template-directed synthesis. The charge transfer transitions and stability constants for supramolecular complexes with hydroquinone derivatives were evaluated by using visible spectroscopy and spectroscopic titration.

Syntheses of phthalocyaninatoiron complexes, Fe(Pcb)L2 and [Fe(Pctb) L]n where Pcb = tetra-tert-butylphthalocyaninato, L = 4,4′-azopyridine (4,4′-APy) or octafluoro-4,4′-azopyridine (4,4′-FAPy), were carried out. These complexes were characterized with TG/DTA, 1H NMR, UV-visible spectroscopy, and cyclic voltammetry. Vpltammetric measurements of soluble Fe(Pcb)L2 in benzene solutions revealed that coordination of axial ligands on Fe(Pcb) greatly influenced oxidation potentials of the central metal moiety. The correlation between conductivities of polymeric [Fe(Pcb)L]n complexes and bandgaps determinedby the voltammetric measurements was identified.

The preparation and electrical properties of iodine-doped phthalocyaninatoiron polymers [Fe(Pc)L]Iyn and[Fe(Pcb)L]Iyn Pc = phthalocyaninato, Pcb = tetra-tert-butylphthalocyaninato, L = 4,4′-azopyridine(4,4′-APy) and octafluoro-4,4′-azopyridine (4,4′-FAPy) were investigated The stoichiometry of polymer complexes was determined by TG/DTA. The iodine-doped [Fe(Pc)(4,4′-APy)]Iyn complexes were semiconducting materials in the range of 10−4 to 10−10S/cm.

Highly ordered polypeptide Langmur-Blodgett films were fabricated from poly(glutamic acid) derivatives. The poly(glutamic acid) derivatives formed stable monolayers at the air-water interface that could be deposited onto solid substrates. The α-helix structure of the poly(glutamic acid) derivatives was confirmed by FT-IR and CD spectrum measurements. Monolayers of tetra-tert-butylphthalocyaninatoiron were transferred onto the poly(glutamic acid) derivative LB films. Monomeric tetra-tert-butylphthalocyaninatoiron molecules existed in the multilayer thin films due to the molecular template effect of the polypeptide LB film. The electrical and optical properties of the multilayer thin films transferred tetra-tert-butylphthalocyaninatoiron or other metal phthalocyanines onto polypeptide LB films were also investigated.

The conductive ultra thin films were fabricated from mixed monolayers containing stearic acid and Head-to-Tail poly(3-alkylthiophene). These films exhibited well-defined layered structures as determined by optical absorption and X-ray diffraction measurements. The UV-Vis absorption spectra of these films showed lower energy absorption shifts of 48 nm from that of the random poly(3-alkylthiophene)/stearic acid LB films. The blue shift of absorption maximum of the LB film is attributed to the increase of π-conjugation length caused by no steric hindrance of alky 1 sidechains. The conductivity of the Head-to-Tail poly(3-hexylthiophene)/stearic acid LB films was greatly improved in the range of 67–100 S/cm.

Summary form only given. The quest for organic and polymeric conductors is of great scientific interest and has spurred research into their electrical, optical, magnetic, and biological properties. Hanack et al. reported that phthalocyaninato metal compounds which were polymerized via bridging heterocyclic amines, have excellent electrical properties. In this paper, the synthesis and properties of new azopyridines-bridged polymers of phthalocyaninato metals are presented. New bisaxially coordinated (phthalocyaninato) metal compounds were synthesized by melting azopyridines and phthalocyaninato metals such as (phthalocyaninato)iron(II) and (phthalocyaninato)cobalt(II), then were purified by sublimation. These complexes were characterized by using NMR spectra, UV-Vis spectra, and TG/DTA. PcML/sub 2/ and (PcML)n [PcM:phthalocyaninato metal, L:azobispyridine ligand] were found to be synthesized by melting the mixture. Additionally, electrical properties of these spin-coated and Langmuir-Blodgett films were investigated.

Polymer complexes consisting of polypyridinium, pyridinium and aluminium chloride are found to be a new class of highly conductive polymer electrolytes, which exhibit a high ionic conductivity of 10–3 S cm–1 at room temperature within range of the conductivity of electrolyte solutions, in spite of film-forming properties.

Direct polycondensation of various nylon salts (salts of dicarboxylic acid and diamine) took place under mild conditions in the formation of polyamide in the presence of polyphosphates and organic bases. Among organic bases imidazole was the best in terms of polymer yields. The reactivity of the polyphosphates was arranged in following order: pyrophosphate ≅ tripolyphosphate > tetrapolyphosphate. Otimum reaction conditions were investigated in terms of solvents, temperatures, and concentration of monomers. A reaction mechanism was proposed for the phosphorylation reaction, due to polyphosphates, which led to the direct polycondensation of nylon salts.

Photosensitivity of cyclized polydienes such as cis-1,4-polybutadiene, 1,2-polybutadiene, and polypentenamer having pendent cinnamate groups has been studied in terms of the influence of polymer structure. The photosensitivity, which was based on the photodimerization of cinnamate groups in these polymers, was greatly affected by the mobility of the cinnamate groups. The observed rates (k) could be estimated by using the reciprocal of the difference between an irradiated temperature (T) and a standardized temperature (Tg – 50), at which the free volume of the polymer could be considered as zero by taking the glass transition temperature (Tg) of the polymer as a standard. Furthermore, the photosensitivity of the cyclized rubber decreased with an increase in the amount of the cyclized units in the polymer. The overall rate of the photodimerization did not linearly correlate with the amount of the incorporated cinnamate groups, because the glass transition temperature of the cyclized rubber was not dependent on the small amount of the incorporated cinnamate groups, but on the amount of the cyclized units in the polymer. Theoretical treatment of the photodimerization reaction in the solid polymer was carried out, which was consistent with experimental results.

Preparation a partir d'un prepolymere, de polymeres segmentes avec differentes compositions de polyoxytetramethylene et polyoxyde d'ethylene

Homopolyamides and copolyamides containing a variety of reactive and/or stabilizing groups, such as double bonds, epoxy groups, or naphthalene moieties, were synthesized using 3-amino perhydroazepine (APA) as a diamine monomer. These polymers were evaluated as electron beam (EB) resists, in order to investigate the relationship between EB sensitivity and chemical structure of the polyamides. It was found that polyamides containing double bonds were easily crosslinked by the EB exposure and that the sensitivity of a polyamide containing double bonds in the side chain was higher than that of a polyamide containing double bonds in the main chain. The sensitivity of a polyamide containing epoxy groups was lower than that of the above. Copolymer from APA, 77 mol % of trans-3-hexenedioyl chloride (HC) and 23 mol % of 2,6-naphthalenedioyl chloride (NC) had the same EB sensitivity as that of the homopolymer from APA and HC. The polyamides had excellent dry etching durability and were adaptable to EB lithography.

Sebacates from alcohols having a 1,4-pyrone nucleus were synthesized, and their reactivities toward diamine were investigated. The polycondensation reactions of di(6-hydroxymethyl-1,4-pyron-3-yl) sebacate or di(2-methyl-1,4-pyron-3-yl) sebacate with hexamethylenediamine took place easily even at room temperature to form a high molecular weight nylon 610 in a quantitative yield. The reactivities of these active diesters with diamine were much higher than that of the corresponding diphenyl ester and were almost comparable to those of acid chlorides. It was also found that inorganic salts such as lithium chloride, zinc chloride, or calcium chloride had a strong influence on the molecular weight of the resulting polyamide. The reactivity enhancement of the active diesters toward aminolysis could be attributed mainly to the acidic character of the leaving group.

Pervaporation d'une nouvelle membrane synthetique contenant un fragment pendant succinimide N-substitue et un groupe ester pendant

Epoxy and formal derivatives of tartarate were found to be easily subjected to polycondensation reactions with hexamethylenediamine (HMD) in solutions under mild conditions and linear polyamides having epoxy or formal groups were obtained in a quantitative yield. The polycondensation reaction of epoxy succinate with HMD was influenced by solvents and a competitive reaction between a nucleophilic attack of amine to ester and epoxy groups was also influenced by solvents.Thus, a cross-linked polyamide was obtained from epoxy succinate and HMD. On the other hand, a linear polyamide was obtained from formal tartarate and HMD. The polyamide from formal tartarate and HMD suffered a cross-linked reaction among the formal groups on heating.

Conductivite ionique de ces polymeres lineaires cristallins en fonction de la temperature et de la teneur en eau

Aromatic polyesters of high molecular weights were prepared by the direct polycondensation reaction of dicarboxylic acids and bisphenols or hydroxybenzoic acids with triphenylphosphine dichloride as a new condensing agent. Reaction conditions, including the amount of reagents and the concentration of monomer, solvent, and acid acceptor, were investigated. The aromatic polyester with the solution viscosity of 1.66 dL/g was obtained from bisphenol. A and terephthalic and isophthalic acid in quantitative yield under the optimum condition. The principal advantage of this condensing agent is that, based on the recycling system, recovered triphenylphosphine oxide can be reconverted to the reactive triphenylphosphine dichloride by treating with phosgene or oxalyl chloride.

Polycondensation of diethyl chelidonate (DEC) with hexamethylenediamine (HMD) took place very rapidly under mild conditions to form a corresponding polyamide. The polycondensation reaction proceeded through the formation of a charge-transfer complex between DEC and HMD, which transformed rapidly into polyamide. Various reaction conditions to form polyamide from DEC and HMD were investigated in terms of solvents, concentration, and temperature. Model reaction of DEC with primary or tertiary amines confirmed the formation of a charge-transfer complex which transformed into chelidonamide except tertiary amine. The polycondensation of DEC with HMD was accelerated by irradiation with light.

A new polymer, poly{1-(2-methylpropenoyloxy)phthalimide-co-acrylonitrile} (Poly(1-co-2)) was synthesized based on molecular designs for the separation of water and ethanol. The sequence distribution of the copolymers were investigated by 13C NMR spectroscopy. A terminal model was used to interpret the propagation process in the copolymerization. The reactivity ratios in the solution polymerization at 45°C were evaluated as r1=1.90 and r2=0.39. Radical reactivity indices and frontier electron densities were calculated. The membrane prepared from this copolymer carried out a selective separation of water from aqueous ethanol solution by pervaporation method. The separation factor toward water was as high as 1200.

Polycondensation reactions of hydroxyl diesters such as dimethyl tartrate (DMT) and diethyl mucate (DEM) with hexamethylenediamine (HMD) were carried out in the presence of poly(vinyl pyridine) (P-VPy) and its copolymers with styrene of different compositions as matrix polymers in order to investigate the difference in interaction forces with monomers or the resulting polyamides owing to hydrogen bonding. It was found that matrix effects of poly(4-vinyl pyridine) (P-4VPy) on the rate enhancement and solution viscosity of the resulting polyamide became more pronounced with decreasing solvent polarity. This result suggests that the matrix effects of P-4VPy on polycondensation are due to hydrogen bonding interactions between hydroxyl diesters and P-4VPy. The addition of P-4VPy increased the molecular weight of the resulting polyamide to a higher extent than poly(2-vinyl pyridine) (P-2VPy), and the molecular weight of the resulting polyamide could be controlled according to the molecular weight of P-4VPy. Copolymer composition of 4-vinyl pyridine–styrene (4VPy/St) copolymers as matrix polymers also affected the molecular weight of the polyamide, which increased with increasing P-4VPy unit contents in the copolymers.

Fully aromatic polyamide containing pyridine moieties (PPy) were successfully synthesized either by interfacial or solution polycondensation to prepare polyamide with inherent viscosity as high as 4. Solution properties of PPy in sulfuric acid were investigated in terms of solution viscosity and lyotropic behavior. The polyamide had a better solubility in sulfuric acid than in poly(p-phenylene terephthalamide) (PT) and the PPy solution in sulfuric acid exhibited an optically anisotropic property in a wider range of concentrations at relatively low temperatures in comparison with the PT solution. Viscosities of the PPy solution and the film cast from the PPy solution indicated a phenomenon characteristic of a highly oriented rigid polymer molecule caused by a lyotropic behavior.

A membrane made of poly(4-vinylpyridine-co-acrylonitrile) was able to actively transport organic acids such as chloroacetic acid and bromoacetic acid against their concentration gradients. These acids were transported not only by an antiport mechanism with OH- transfer, but also by a symport mechanism with H+ transfer. The transport of organic acids was represented by a flux equation.

Ion conduction mechanism in network polymers from poly(ethylene oxide) and poly(propylene oxide) containing lithium perchlorate was investigated in their amorphous and rubbery state, based on the results of the temperature dependences of ionic conductivity and mobility. The temperature dependences of ionic diffusion coefficient and the number of carrier ions obeyed the WLF-type and the Arrhenius equations, respectively. The ionic conductivity was interpreted by the superposition of these processes. The difference in the ionic conductivity for these two polymer complexes was discussed.