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Dialdehyde konjac glucomannan (DAKGM) was synthesized by konjac glucomannan via sodium periodate (NaIO4) as an oxidant and characterized by NMR and FTIR spectroscopy techniques. The results indicated that the oxidization of KGM catalyzed by NaIO4was highly selective for C2 and C3 of sugar units to form aldehyde group. Further, the solution behaviors of DAKGM were investigated by steady-state fluorescence. DAKGM exhibited two emission peaks at maximum wavelength 425 nm and 465 nm, respectively.

In the paper, the thermo-properties of unsaturated polyester resin (UPR)/epoxy resin(E51) composites through reactive blending method were studied by DSC. The experimental results showed that, when the amount of E51 in UPR/E51 composites reached to 2wt%, the mixture take place glass transition at 84°C which higher than that of pure UPR 15%. When the amount of E51 reached to 10wt%, the mixture take place two glass transition at 59°C、104°C respectively. The morphologies of the mixtures were investigated by SEM, and the curing process of UPR/E51 was traced and investigated by FTIR.

Konjac glucomannan (KGM) gel was prepared by alkali catalyzed in aqueous solutions. The structure of the KGM gel was characterized by Fourier transform infrared (FTIR) spectroscopy and wide angle X-ray diffraction (WAXRD). The gel point of KGM solutions was determined by steady state fluorescence method and It was observed that the gel point of the KGM solutions depend on the concentration of KGM, pH value and temperature effectively. The results showed that the molecular chain structure of KGM gel is more regular than that of the pure KGM.

Konjac glucomannan (KGM) has been widely used in pharmaceutical, chemical engineering, food industry, drug carrier delivery, etc. The sol-gel transition kinetics of KGM dilute solution was studied by steady fluorescence spectroscopy in this article. The results showed that the gel point of KGM solutions depend on the concentration of KGM, pH value and temperature. The sol-gel phase transition activation energy, ΔE, was calculated to be 83.1 kJ/mol based on first reaction kinetic model.