Original Article in 2010

X-ray scattering from an organogel made from discotic triazine triamide was measured at SPring-8 at a quite wide q range of 0.050 nm⁻¹ <q <20 nm⁻¹. Analyses revealed (1) an amorphous nature of the molecular stacking at a distance of 0.32 nm, (2) the presence of a semiflexible rod-like scattering object with a radius of 1.3 nm and a Kuhn length of 55 nm and (3) branching of the cylinder formed at the gel state.

The reaction in the presence of poly(γ-glutamic acid) (γPGA) proceeded faster than that without γPGA and the larger molecular weight γPGA was slightly more efficient to catalyze the reaction.

The molecular chaperone function of polysaccharide nanogel was demonstrated for the folding of newly synthesized green fluorescent protein (GFP) in a cell-free protein synthesis system. Nanogel comprising cholesteryl group-bearing pullulan (CHP) trapped unfolded or partially folded GFP expressed in the cell-free system. The structure of the CHP nanogel was disrupted by the addition of cyclodextrins, and the protein complexed with the nanogel was released and folded into the mature form.

PPMC with a high M_n of up to 6.0 × 10⁴ g mol⁻¹ can be readily afforded under the catalysis of an immobilized lipase from Candida antarctica (Novozym-435). The result sounds attractive, as presently the low catalytic efficiency is known as the main restriction for the industrialization of enzyme catalysis.

Liquefied bamboos were multihydroxy compounds and could react with bisphenol-A and epichlorohydrin to prepare a novel epoxy resin. Curing behavior of copolymer epoxy resins prepared with phenol- and polyhydric alcohol-liquefied bamboo could be analyzed by differential scanning calorimetry and dynamic mechanical analysis to obtain more advanced information.

Allyl benzoate (ABz) was polymerized using dicumyl peroxide (DCPO) at 130 °C; almost no direct contribution of cumyloxy radical to initiation reaction was observed. This was extended to other organic peroxide initiators; it was confirmed that the initiation by methyl radical generated by β-scission of alkoxy radicals occurred predominantly in allyl polymerization at elevated temperatures.

New oligomeric electrolytes with a number of different anions were obtained in high yields by anion exchange reactions. Although the starting material with chloride as a counter anion was not soluble in any organic solvent, the excellent miscibility and gelation ability of the oligomeric electrolytes were consequently observed with dipolar protophilic and aprotic solvents. Furthermore, the ionogels based on aliphatic ionic liquids were readily formed using the oligomer with bis(trifluoromethanesulfonyl)amide anion at a 40 g l⁻¹ concentration.

Novel combined liquid crystalline (LC) polymers based on ethyl cellulose (EC) were synthesized by N,N′-dicylcohexylcarbodiimide coupling, and the effect of flexible spacer length on the mesophase structure was investigated. The results showed that the mesophase structures of polymers consisted of a large-scale ordered lamellar structure constructed by EC backbone and a relatively small-scale ordered structure formed by azobenzene side chains. All the polymers form the similar lamellar structure at large scale; however, the small-scale ordered structure becomes disordered relatively, that is, from crystal (m=2) to smectic B (m=4) to smectic A (m=6) at lower temperature.

Maleic anhydride grafted polypropylene (PP-g-MA) with different grafting contents and approximately the same molecular weight was prepared. The grafting content of PP-g-MA in the range of 0.2–1.4 wt% shows no appreciable influence on the dispersion of organoclay, whereas the loading of PP-g-MA can effectively influence the intercalation and delamination of clay. The intercalation and exfoliation mechanism of prepared PP-g-MA is discussed and compared with that of PP-g-MA oligomer.

The effective volume V_E excluded to a Kratky–Porod (KP) worm-like ring by the presence of another, resulting only from a topological interaction, was evaluated by Monte Carlo simulations. The quantity λV_E/L² proportional to the second virial coefficient A₂ was shown to be a function only of λL with λ⁻¹ the stiffness parameter of the KP ring and L its total contour length.

An antibacterial quaternary ammonium acrylic monomer 1 was synthesized by quaternization of 2-dimethylamino ethyl methacrylate with dimethyl sulfate. This synthetic route was able to obtain the quaternary ammonium monomer 1 of high yield and low cost. The corresponding homopolymers were then synthesized by free radical polymerization using potassium persulfate as the initiator and H₂O as the solvent. Interestingly, it was found that 2 had significantly higher antibacterial activity than 1, although 1 exhibited moderate antibacterial activity.

Condensation reactions between tetraethylorthosilicate and cyclohexanediol derivatives resulted in crosslinked poly(orthosilicate)s. These polymers have good and fast swelling abilities in organic solvent and they also release the absorbed solvent very easily.

Aniline sulfide resin (ASR) is synthesized by the reaction of aniline and sulfide dichloride. Crosslinked ASR (ASC) has been prepared in the presence of ammonium peroxydisulfate and aniline in aqueous solution as oxidant and monomer, respectively. By changing the ratio of ASR to aniline during the polymerization reaction, it is possible to control the number of crosslinked sites, electrical conductivity, molecular weight and solubility. Electropolymerization was carried out by coating ASR on the surface of glassy carbon disk electrode, and then grown on a graft copolymer ASC in the presence of fresh aniline and acidic solution. Electrical conductivity of ASC has been studied by four-point probe method and produced 8.5 × 10⁻³ S cm^–1 conductivity for it.

Cast technique was used to prepare new nanocomposite thin films of pure and GdCl₃- or HoCl₃-doped polyvinylpyrrolidone (PVP) with different dopant concentrations. During magnetic measurements, using a vibrating sample magnetometer, carried out at room temperature and applied magnetic fields up to 10 kO_e, thin films of the system PVP-HoCl₃ showed slightly better magnetic properties than PVP-GdCl₃. A comparative infrared and ultraviolet-visible spectral analysis of the parent components and their nanocomposites provided an indication to the effective role of dopant nature and concentration in morphological and microstructural changes occurring in the PVP matrix.

Novel fluorescent polyimides (PIs) were prepared from a new diamine, 4-(4-(4-amino-2-(4,5-diphenyl-1Hi-midazol-2-yl)phenoxy)phenoxy)-3-(4,5-diphenyl-1H-imidazol-2-yl)benzenamine(DA), and three tetracarboxylic dianhydrides. The PIs are amorphous and soluble in polar aprotic solvents and demonstrate a film-forming capability; their inherent viscosities ranged from 43 to 82 ml g⁻¹. The PIs show emission in dilute (0.2 g per 100 ml) N,N-dimethyl acetamide solution with photoluminescence (PL) quantum yields in the range of 11–25%. The chemiluminescence (CL) activity of PIs in the presence of peroxyoxalate was also investigated.

Asymmetric anionic homopolymerizations of N-4′-benzo 15-crown-5 maleimide (B15C5MI) were carried out with a chiral anionic initiator consisting of organometal and chiral ligand to obtain optically active polymers. Chiroptical properties and structures of the polymers obtained were analyzed by CD, UV, NMR and gel permeation chromatography measurements. The additional effects of (R)-cyclohexylethylamine ((R)-Cyc) to the obtained poly(B15C5MI) were investigated.

Sulfonated free-standing films were prepared by sulfonation of the free-standing films of 3-mercaptopropyl(trimethoxy)silane (MTMS)/1,2-bis(triethoxysilyl)ethane (BTESE) copolymers. The sulfonyl group content was 1.23 mmol g⁻¹ when the composition of MTMS/BTESE was 1:2, which sulfonyl group content at 150 °C was 1.20 mmol g⁻¹.

The WAXD image and the fiber temperature were measured as a function of elapsed time t calculated on the basis of the distance (D) from the neck-drawing point divided by the fiber running speed. The distance D was controlled by shifting the neck-drawing point with the traveling mirror unit.

Vaterite particles were obtained by a ‘carbonate controlled-addition method’ by G0.5 poly(amidoamine) (PAMAM) dendrimer with carboxylate groups at the external surface. The average particle sizes of the spheres decreased from 2.2±0.2 to 0.61±0.24 μm and the stability of the spheres increased with an increase in the incubation time of the G0.5–CaCl₂ solution from 3 min to 24 h. The interaction and reaction kinetics of the dendrimer–Ca²⁺ complex have an important role in the mineralization of CaCO₃.

When poly(methyl methacrylate) (PMMA) film doped with (Z)-N-acetyl-α-dehydroarylalanine naphthyl esters ((Z)-1) was irradiated with unfiltered light from a high-pressure mercury lamp, (Z)-1 underwent heterolytic cleavage of the ester bond preferentially in PMMA film to give arylmethylene-substituted oxazolone and naphthol derivatives as major products. This photochemical transformation enhanced the refractive index of this polymer film in the range of 0.001–0.020, depending on the structure of the aryl substituents.