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In this work, a one-step hydrothermal route is developed to prepare WO3·nH2O crystals with various morphology/phases, for which any surfactants, templates, or structure-directing agents are not used. Five types of WO3·nH2O crystals, including o-WO3·H2O nanoplates, rectangular m-WO3 nanosheets, o-WO3·0.33H2O microspheres, h-WO3 nanorods, and bundle-like h-WO3 hierarchical structures, are successfully obtained by adjusting the amount of H2SO4 and reaction temperature. According to the experimental results, the formation mechanism for various WO3·nH2O species is proposed. In addition, the optical absorption properties of these WO3·nH2O crystals are also investigated by UV–vis absorption spectra.

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In this study, the cross-linked network structures, dynamic mechanical properties and Po、PRI of microbe coagulated natural rubber (NR) samples were analyzed. And mechanical properties of the corresponding NR vulcanizates were further determined by universal testing machines. The results show that the NR of aging resistance increased with the cycle of hanging.When hanged 14 days,the PRI and P0 were 85 and 36.6. With the cycle of hanging rising, NR raw rubber of cross-linked density increased,and had good dynamic mechanical properties as compared with that hanged 0 days.

The storage lifetime of nature rubber vulcanizes dried by microwave and hot-air was investigated by using thermogravimetric point slope (TPS) method. The results showed that the storage lifetime at ambient temperature of nature rubber vulcanizes dried by microwave was 9 years which was 1.2 years longer than hot-air. Microwave drying nature rubber vulcanizes showed a better thermal-oxidation ageing resistance and a longer storage lifetime. It provided theoretical guide and basis for practical application.

The effects of drying methods on thermal-oxidation degradation and ageing behavior of nature rubber (NR) was investigated using Fourier transform infrared/Attenuated total reflection (FTIR-ATR) and thermogravimetric analysis. Examining the samples of thermal-oxidation ageing for 24h by FTIR-ATR spectroscopy allowed appearance of obvious carboxyl absorption of hot-air drying NR at 1723cm-1, decay of methylene stretch and C=C plane stretch during thermal-oxidation ageing process, to be monitored. TG and DTG were used to determine thermal-oxidation degradation temperature in air atmosphere and active energy using Coats-Redfern equation. Showed from the results, the degradation temperature and active energy of microwave drying NR was higher than hot-air drying, thermal-oxidation resistance was more excellent by FTIR analysis, indicating a higher thermal-oxidation stability of microwave drying NR.