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Abstract: A new supermolecular assembly crystal, [C6H8N2]6H3[PW12O40]·2H2O (DMB–PWA), was synthesized with phosphotungstic acid (PWA) and 1,2-diaminobenzene (DMB) under hydrothermal conditions and was characterized by Fourier-transform infrared spectra (FTIR) and single-crystal X-ray diffraction analysis. DMB–PWA could effectively catalyze oxidative degradation of chitosan with H2O2 in the heterogeneous phase. The optimum degradation conditions were determined by orthogonal tests as follows: amount of chitosan 1.00g, 30% (wt %); H2O2, 3.0mL; dosage of catalyst, 0.06g; reaction temperature, 85°C; and reaction time, 30min. The water-soluble chitosan with a viscosity-average molecular weight (M v) of 4900 was obtained under the optimum degradation conditions and was characterized by FTIR, ultraviolet–visible diffuse reflection spectra (UV–vis DRS), and X-ray powder diffraction analysis. [Copyright &y& Elsevier]

Abstract: Phosphotungstate (PTA), an insoluble catalyst synthesized with phosphotungstic acid (PWA) and chitosan in acidic reaction system by electrostatic attraction. The catalyst was characterized by DRS and FTIR spectra. Under the catalysis of PTA, the heterogeneous degradation of chitosan with H2O2 was achieved. The effect of volume of H2O2, dosage of catalyst, reaction temperature and time on the degradation was discussed by orthogonal tests. The experimental results show that chitosan can be effectively degradated with H2O2 under the catalysis of PTA. The catalyst, PTA, may have a promising application in oxidative degradation of polymer. [Copyright &y& Elsevier]

In the title 1:1 adduct, C(10)H(10)O(4)·C(12)H(10)N(2), the two components are linked by O-H⋯N hydrogen bonds to form a one-dimensional chain. The dihedral angle between the pyridine rings is 15.68 (8)° These chains are further inter-connected by weak inter-molecular C-H⋯O hydrogen bonds and weak C-H⋯π inter-actions to generate a three-dimensional network.