Preparation And Mechanical Properties Of Bionic Nacre Material

Nacres have received wide attention for unique structure and excellent mechanical. This study bionic nacres which use the organic polymer layer polyelectrolyte as the protein layer of nacres, and the inorganic TiO2layer as mineral thin of nacres. Apply layer-by-layer Self-Assembly (LBL) and Chemical Bath Deposition method (CBD) to prepared TiO2/PE nanocomposite film in different substrate, and study its mechanical properties.The silicon of (001) crystal orientation and polyimide are used as substrate in this experiments. Scanning Electron Microscopy with Energy Dispersive Spectrum and laser scanning confocal microscope are using for characterizing and analysising on the prepared nanocomposite film morphology, surface roughness and composition. Micro-hardness tester and tensile instrument are applied for studing on the mechanical properties of prepared nanocomposite films. Conclusions can be drawn as follows:(1) LBL and CBD method can be used to prepare TiO2/PE nanocomposite films with bionic nacres structure at different substrate.(2) The best experimental conditions to prepare single-layer TiO2/PE nanocomposite films is PE use in PEI/PSS (PAH/PSS)3structure, a single polyelectrolyte deposition time is15min, deposition temperature of TiO2is60℃and deposition time is3h. During the multi-layer TiO2/PE nanocomposite films, six layers composite film is the best in quality and thickness.(3) TiO2/PE nanocomposite films under the optimal experimental conditions are the best worth with the composite film hardness and fracture toughness.(4)In the same experimental condition, four layers TiO2/PE nanocomposite films are the highest hardness. Hardness is about1.65GPa.Six layers composite films are the best fracture toughness and it is about25.44MPa-m1/2. Six layers composite films are the best synthesis mechanical properties.