A nanocomposite of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH)/ montmorillonite (MMT) modified with silane coupling agent 3-aminopropyltriethoxysilane (KH550) (PHBH/MMT/KH550) was prepared by solution casting method. The effects of KH550 content on properties of nanocomposites were comparatively investigated. According to the Fourier transform infrared spectra, the new chemical bonding between the PHBH and the MMT was formed by adding KH550. The crystallinity, thermal properties, mechanical properties, and barrier properties of the nanocomposites were improved because of the good dispersion of MMT. Compared with pure PHBH, a 220.05%, 158.25%, and 58.91% improvement in young's modulus, tensile strength, and elongation at break was obtained. The water vapor transmission coefficient was decreased by 113.30%. Moreover, it was notable that the nanocomposite possessed the optimal mechanical properties when the KH550 content was 5 wt%.The obtained results revealed that the nanocomposite will expand the practical application of PHBH base plastics as a substitute of traditional petrochemical materials.

In this study, a poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) modified with nano-montmorillonite biocomposite (MMT/PHBH) was fabricated by solution-casting method. The results showed that the addition of MMT increased the crystallinity and the number of spherulites, which indicated that MMT was an effective nucleating agent for PHBH. The maximum decomposition peak of the biocomposites moved to a high temperature and residue presented an increasing trend. The biocomposites showed the best thermal stability at 1 wt% MMT. Compared with PHBH, 182.5% and 111.2% improvement in elastic modulus and tensile strength were obtained, respectively. Moreover, the oxygen permeability coefficient and the water vapor permeability of MMT/PHBH biocomposites decreased by 43.9% and 6.9%, respectively. It was also found that the simultaneous enhancements on the crystallizing, thermal stability, mechanical, and barrier properties of biocomposites were mainly caused by the formation of intercalated structure between PHBH and MMT.

Mn-doped TiO2 loaded on wood-based activated carbon fiber (Mn/TiO2-WACF) was prepared by sol–gel and impregnation method using MnSO4·H2O as manganese source. The structure of Mn/TiO2–WACF was characterized by SEM, XRD, FTIR, N2 adsorption and UV–Vis, and its photocatalytic activity for methylene blue degradation was investigated. Results show that Mn-doped TiO2 were loaded on the surface of wood-based activated carbon fiber with high-development pore structures. The crystallite sizes of Mn-doped TiO2 in composites were smaller than that of the undoped samples. With an increase of Mn doping content, Ti–O bending vibration intensity of Mn/TiO2–WACF increased and then decreased. Moreover, Ti–O–Ti and Ti–O–Mn absorption peaks increased upon doping of Mn. Mn/TiO2–WACF with low specific surface area, and pore volume was improved at 3.5–6.0 nm of mesopore distributions due to the Mn-doped TiO2 load. In addition, the UV–Vis showed that Mn/TiO2–WACF (photodegradation rate of 96%) has higher photocatalytic activity than the undoped samples for methylene blue degradation under visible light irradiation.

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