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Highly dispersed molybdenum trioxide were loaded in three-dimensional dendritic mesoporous silica nanospheres (MoO3@3D-DMSNs) by one-pot method. The mesoporous silica nanospheres with central radical channels were obtained through the interaction of bisurfactant and molybdenum source and the as-synthesized MoO3@3D-DMSNs were characterized by specific tests. As a result, the as-prepared MoO3@3D-DMSNs exhibited better catalytic performance for epoxidation of olefins. When the molar ratio value of Mo and Si is 5%, the specific surface area (SBET = 185.8 m2/g) and pore volume (Vp = 0.46 cm3/g) of MoO3@3D-DMSNs reach a maximum, and the catalytic activity is the best for the epoxidation of cyclooctene. The conversion could reach 84% with a selectivity above 98% after 6 h. The better catalytic performance can be maintained after five reaction-regeneration cycles. The dendritic mesoporous structure can be well preserved after recycling. Additionally, olefins with electron-absorbing group exhibit better catalytic activity with MoO3@3D-DMSNs-5 as catalyst. Hence, MoO3@3D-DMSNs catalysts with the center-radial oriented channel exhibit good activity and stability. The central radial channel can effectively disperse the active center MoO3 and play a key role in the transmission and accessibility of substrates, and it would have a good application prospect in the catalytic reactions.

Nowadays, environmental problems such as petroleum resources exhaustion, pollution and global warming are in ceaseless aggravation. Consequently, vegetable oil becomes one of the most important resources due to its cheapness, easily availability and environmental regeneration. In this study, a series of sustainable polyurethanes based on epoxy soybean oil modified by different contents of 3,13-dimethyhydroxysilyl double-decker phenylsilsesquioxane [DDSQ(Me)OH] have been prepared. Polyol prepared with epoxy soybean oil has effectively replaced the petroleum-based polyol and the DDSQ(Me)OH performed as chain extender together with 1,4-butanediol (BDO). The structure of DDSQ(Me)OH was verified by 1H NMR and MALDI–TOF–MS. The structure and properties of sustainable polyurethanes were characterized by FTIR, DSC, TGA, SEM, tensile test and static contact angle. TGA demonstrated that hybrid polyurethanes were thermally stable due to the covalent incorporation of DDSQ(Me)OH in polymer main chain, the 5% weight loss temperatures (Td5) of hybrid polyurethane can be 21 °C higher than pure PU. DSC revealed the improved glass transition temperature (Tg) of polyurethanes, and the Tg can be 12.4 °C improved compared with pure polyurethane. SEM showed that the aggregation of DDSQ(Me)OH has dispersed homogeneously in the hybrid polyurethanes matrix. The results of the static contact angle revealed that with the increase of DDSQ(Me)OH content, the surface hydrophobicity has been enhanced significantly, and the static contact angle of water for hybrid polyurethanes can be up to about 110.2°.

Hybrid polyurethanes with double-decker silsesquioxane (DDSQ) in the main chains were synthesized using castor oil and isophorone diisocyanate (IPDI) as feedstock. Double-decker octaphenylsilsesquioxanetetraol (DDSQ) was prepared and characterized by 1H NMR and MALDI-TOF–MS. Meanwhile, FTIR, TGA, DSC, SEM, UV–Vis spectrophotometer, tensile test techniques and static contact angle were also carried out to investigate the structures and properties of the hybrid polyurethanes. The DDSQ-containing hybrid polyurethanes exhibited improved thermal stability in terms of thermogravimetric analysis (TGA). DSC analysis demonstrated that the hybrid polyurethanes with DDSQ displayed enhanced glass transition temperature. According to the results of SEM and UV–Vis spectrophotometer, the aggregates of DDSQ were dispersed homogeneously in the hybrid polyurethanes matrix. With the inclusion of DDSQ, the hydrophobicity of the hybrid material was significantly improved as the results of the static contact angles revealed.