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Interpolymer complexes of microbial poly(ɛ-L-lysine) (ɛ-PL) and poly(acrylic acid) (PAA) were studied by Fourier transform infrared spectroscopy, differential scanning calorimetry and solid-state 13C and 15N nuclear magnetic resonance (NMR) experiments. These measurements suggested the poly-ionic complex formation between ɛ-PL and PAA, ɛ-PL-H3N+···−OOC-PAA. By analyzing 13C NMR spectra of the complex, we concluded that there exist three forms of the carboxyl group of PAA, namely: (1) the ionized form, interpolymer ion-complex between ɛ-PL and PAA, (2) the dimeric form, intrapolymer hydrogen bonding among PAA molecules and (3) the free form, no particular form of hydrogen bonding.
Here, we show that a sulfonated polyaramide exhibiting a lyotropic liquid-crystalline phase in aqueous solution gives optically active films through spin-coating, and that their chiral handedness can be tuned using the rotational direction. We further suggest that hydrogen-bond formation between polymer backbones have a key role in inducing selective chiral signs.
Polymer nanoparticles (PNPs) that consist of a low-bandgap conjugated polymer, co-poly(2,3-diphenylthieno[3,4-b]pyrazine-alt-9,9-dioctylfluorene), were prepared for the photoluminescence in vivo imaging in the near infrared region. The emission efficiency was enhanced by the fluorescent resonance energy transfer from the conjugated polymer to a silicon naphthalocyanine dye. The dye-doped conjugated PNPs enabled the bright fluorescence imaging of live mice.
Aromatic-ring-layered polymers were synthesized by Sonogashira–Hagihara coupling reaction using xanthene as a scaffold. The polymers were characterized by various spectroscopic and electrochemical methods. The polymers emit brightly without excimer formation, despite the layered structure.
A biomass-based thermoplastic with ingredients derived from non-food plant resources with stable supply was produced by bonding cellulose diacetate (CDA) with cardanol, a primary component of cashew nutshells. Esterification of the modified cardanol (cardanoxy acetic acid chloride) and CDA resulted in a thermoplastic with high water resistance, great tenacity and high heat resistance. These properties were as a result of the combination of cardanol, which is flexible and hydrophobic, and CDA, which is rigid and resistant to heat deformation.
The prototype touch screen fabricated using the poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate)/polycarbonate (PEDOT/PSS/PC) film as a transparent electrode principally works as a touch pad for dragging (writing) a number ‘2’ by a finger.
Thermal-dependent six-membered cyclic anhydrides were formed in the Eudragit E and polyvinyl alcohol (PVA) copolymer via intramolecular ester condensation by using differential scanning calorimeter (DSC)-Fourier transform infrared microspectroscopy. The temperature for intramolecular ester condensation was started from 180 °C for Eudragit E, but from 167 °C for PVA copolymer. The amount of intramolecular anhydride formed in the film of Eudragit E was found to be higher than that formed in the film of PVA copolymer during the heating process.
Streptavidin-immobilized magnetic beads and poly(ethylene glycol) covalently immobilized streptavidin-immobilized magnetic beads were prepared to investigate the heat resistance of streptavidin surrounded by a densely packed poly(ethylene glycol) tethered-chain layer on the magnetic bead surface. The covalent immobilization of poly(ethylene glycol) tethered-chains on the streptavidin-immobilized magnetic beads surface was carried out using α-methoxy-poly(ethylene glycol)-pentaethylenehexamine (N6-PEG) after streptavidin immobilization. Figure shows changes in the capture efficiency of biotinylated single-stranded DNA by poly(ethylene glycol)/streptavidin-immobilized magnetic beads (red plots) and streptavidin-immobilized magnetic beads (blue plots) as a function of the number of heat-treatment cycles (75 °C for 5 min). Surprizingly, the heat resistance of the poly(ethylene glycol) tethered-chain covalently immobilized on the streptavidin-immobilized magnetic beads surface was found to improve.
The highly soluble hyperbranched oligothiophene (SH-oligothiophene), which is composed of bithiophene and N,N,N′,N′-tetraphenyl-1,3-phenylenediamine groups, is newly prepared and the photocarrier transport property of the SH-oligothiophene film prepared by spin coating from a chloroform solution is investigated by a time-of-flight method. Transient photocurrent profiles indicate that hole carriers drift preferentially compared with electrons and that dispersive transport characteristics are obtained.
Hyperbranched fluorinated polymers with different fluorine contents and comonomer structure were synthesized by A2+B3 polymerization of phenol derivatives (A2 monomer) and 1,1′,1′′-tris(4-glycidyloxyphenyl)methane (B3 monomer). The nD was affected by the monomer and polymer structures, and the fluorine content of hyperbranched polymers. Cured materials tended to increase nD because of the increase of crosslinking density of the film.
