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The waterborne polyurethane acrylate (PUA) dispersion was prepared based on polyester polyol, isophorone diisocyanate, dimethylol propionic acid, butyl acrylate and trimethylolpropane triacrylate. Then, a series of PUA/SiO 2 hybrid dispersions were prepared from PUA dispersion, coupling agent 3-glycidyloxypropyl trimethoxysilane and different content tetraethoxysilane hydrolysis solutions by the sol-gel process. The physical properties of PUA/SiO 2 hybrid dispersions and the mechanical properties of PUA/SiO 2 hybrid composites were measured. The PUA/SiO 2 hybrids were characterised. The results showed that the nano-SiO 2 particles of the hybrids had good dispersion and formed a good interfacial bonding layer on its surface. When the tetraethyl orthosilicate content was 0?5 wt-%, the hybrid film exhibited excellent comprehensive mechanical properties and water resistance. The tensile strength, hardness and water absorption of the film were 3?32 MPa, 90 and 6?7% respectively. The obtained PUA and hybrid composites have great potential application, such as coatings, leather finishing, adhesives, sealants, plastic coatings and wood finishes.

As a positive electrode material for lithium-ion batteries, LiFePO4 should be composited with carbonaceous materials due to its poor electrical conductivity. In this study, LiFePO4/C (carbon) composite was synthesized with method of solution co-precipitation, in which glucose was used as a carbon source. The LiFePO4 material was systematically optimized by X-ray diffraction, scanning electron microscopy. The crystalline structures, morphology and electrochemical performance of LiFePO4 prepared by solution co-precipitation were compared with that obtained by solid-state reaction. It is found that LiFePO4 is a pure phase with olivine structure, and exhibits a 3.4V discharge voltage plateau. In our experimental conditions, LiFePO4/C including 10wt. % of residual carbon obtained by solution co-precipitation possess excellent electrochemical performance, whose first specific capacity was 131.4 mAh•g-1 at 0.1C rate, the specific capacity was 128.3 mAh•g-1 after 20 times cycling.

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