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See the article by Nagatoshi Koumura, Hajime Matsumoto, Hajime Kawanami, Nobuyuki Tamaoki and Masaru Yoshida, Tuning of solubility and gelation ability of oligomeric electrolyte by anion exchange on page 759.
Hyperbranched poly(ether sulfone)s (HBPES) possessing sulfonic acid at the terminal point were prepared by the electrophilic reaction of sulfonium ions to electron-rich benzene rings starting two kinds of AB2 monomers. First, linear and hyperbranched multiblock copolymers were successfully prepared by the reaction of oligomeric linear PES and AB2 monomer. Next, from these multiblock copolymers, a linear and hyperbranched PES blend was prepared and applied as ion-exchange membranes for fuel cells. The blend films showed comparable ion-exchange capacity with Nafion 117 membrane.
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.
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.
PPMC with a high Mn 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.
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 kOe, 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.
The effective volume VE 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 λVE/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.
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.
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.
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.
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.
Poly(fluorene) composed of alternating structures are considered to assume an ordered macrostructure involving lamellar and π–π stacking in the film state. The ordered structure gives rise to perfect interpolymer excimeric luminescence, which can be used as a luminescence layer in an electroluminescent device.
