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Glycosaminoglycans (GAGs) are one of the most important polysaccharide in the living systems. However, preparation of GAGs is difficult owing to the complex structure and high molecular weight. In order to obtain the GAGs’ materials with a practical way, we investigated a new approach to mimic GAGs using polymer chemistry. We reviewed the syntheses of GAGs of the previous reports and the glycopolymers having GAGs moieties, including our GAGs' mimic polymers.
We studied the structure of polybutadiene rubber (BR) crosslinked with zinc diacrylate (ZDA) to elucidate the structure of the high crosslink density BR (HC-BR) using a contrast variation small-angle neutron scattering (CV-SANS) method. The careful analysis revealed the existence of a HC-BR layer around the ZDA aggregates. This is the first time quantitative structural analysis of the HC-BR layer in this rubber material has been performed. In addition, the network structure of the HC-BR layer in the rubber matrix is responsible for the high mechanical modulus of the rubber.
When water is added to dilute MeOH solutions of a hydrophilically modified poly(dimethylsiloxane) (HPM-PDMS), molecularly dispersed HPM-PDMS chains associate to form colloidal droplets of the concentrated phase, which are charged spheres of uniform density with the radius of gyration less than 100 nm. Those droplets are remarkably different from those in solutions of HPM-PDMS directly dissolved in MeOH–water mixtures with⩾0.5 and including 0.1 m NaAc, which may contain the coexisting dilute phase.
Many molecules of normal tricosane in the rotator phases belong to any one of three types of rows of molecules as shown in the figure. In the three stable conformations, they are making the translational motion along and the rotational oscillation around the molecular axes. The estimation of disorder parameters relevant to the thermal motions shows that the translational motion and the rotational oscillation are fairly restricted in the rotator phases.
Block antibacterial polyurethane and terminated antibacterial polyurethane were prepared based on N-methyl-N-dodecyl-N,N-bis(2-hydroxyethyl) ammonium bromide. Their antibacterial properties were determined using qualitative and quantitative tests, and the physical performances of the antibacterial polyurethane (APU) were also investigated. The results indicate that the APUs display marked mechanical properties, water absorption and improved antibacterial properties against Escherichia coli, Staphylococcus aureus and Bacillus subtilis, with the most potency against E. coli.
Photoinduced orientation of H-bonded composites of non-photoreactive polymethacrylate consisting of a benzoic acid (BA) moiety (pM6BA) and 4-methoxycinnamic acid (4MCA) is investigated. The pM6BA/4MCA composite films exhibit liquid crystal characteristics owing to H-bonds between BA and 4MCA as well as between the BA groups. Exposure to linearly polarized UV light gives rise to axis-selective photoreaction of the 4MCAs, while thermal treatment induces the molecular reorientation of the BA side groups accompanied by the sublimation of unreacted 4MCA.
A simple and versatile method for the visualization of swollen microgels was developed to apply water-soluble ionic liquids using the standard scanning electron microscopy. Au nanoparticles were synthesized within microgels as indicators of the expansion of the microgels, and then the hybrid microgels were observed by conventional (left) or our method (right). The Au nanoparticles were dispersed due to the swelling of microgels caused by the ionic liquids. This visualization method is useful to evaluate internal structure of metal composite gel materials.
The C2-, C3-, and C8-linked star-shaped isobutyl-substituted caged silsesquioxane derivatives (3a, 3b and 3c) were prepared by the hydrosilylation of mono-vinyl-, allyl- and octenylisobutyl-T8-silsesquioxane, respectively, along with the synthesis of octadimethylsiloxy-Q8-silsesquioxane. 3a and 3b formed optically transparent films. However, 3c formed an opaque white film. Wide-angle X-ray scattering measurements suggested that 3a and 3b formed more tightly packed structures after melting. However, 3c formed a less dense structure after melting. The refractive index of the film of 3a was lower than that of 3b.
A short-range-ordered, soft glassy colloidal array (SGCA) exhibits angle-independent and non-iridescent structural color. To control the angle-independent structural color by external stimuli, a thermosensitive SGCA composed of block copolymer (poly(benzyl methacrylate)-block-poly(methyl methacrylate), PBnMA-b-PMMA) grafted silica nanoparticles was prepared in an ionic liquid. The glassy arrays showed a blue shift of reflection peak at semidilute particle concentrations, but an opposite red shift at high particle concentrations with increasing temperature.
A casein–inorganic hybrid material was prepared by mixing casein, one of phosphoproteins, and a silane coupling reagent. This casein–inorganic hybrid material was stable in an aqueous solution owing to the electrostatic interactions between the phosphate group in casein and the amino group in the silane coupling reagent. The hybrid materials could selectively accumulate heavy and light metal ions and did not interact with the rare-earth metal ions. In addition, the metal ion-accumulated hybrid materials could be recycled by washing with an aqueous EDTA solution or hydrochloric acid.
The incorporation of SPAni within SPVdF, to form SPVdF/SPAni blend membranes, increased the %WU, the %SR, the IEC, the proton conductivity and the membrane selectivity of the base SPVdF membrane, whereas substantially decreased the %MUs and the methanol permeability values. The SPVdF/SPAni (80/20) blend membrane was found to produce the lowest methanol permeability values of 1.50 × 10−9 cm2 s−1 (at 2 m methanol) and 6.30 × 10−9 cm2 s−1 (at 8 m methanol) and the highest membrane selectivity values of 3.27 × 106 Ss cm−3 (at 2 m methanol) and 7.78 × 105 Ss cm−3 (at 8 m methanol).
A facile synthesis of ABA triblock copolymers composed of aliphatic polyesters and aromatic polyimides was performed by ring-opening polymerization ɛ-caprolactone and L-lactide initiated by hydroxy-terminated polyimide.
This study explores the relationship between the mechanical properties and composite structure of a bacterial cellulose/polyethylene glycol (BC/PEG) gel with a peripheral region that is crosslinked by polyethylene glycol diacrylate (PEGDA). The results indicated that the mechanical strength of the gels was dependent not only on the amount of crosslinked PEGDA, but also on the extent to which the composite structure extends below the surface. As retention of the fiber phase is vital to reducing the brittleness of the material, the concentration gradient of the PEGDA polymer is a critical factor.
