The Study And Application Of Polyelectrolyte Layer-by-layer Self-assembly Multilayers On Monodispersed ZnCO₃ Microparticles And Mica

Self-assembly multilayers of layer-by-layer polyelectrolyte depend on the electrostatic adsorption, namely the polyelectrolyte with the opposite charge alternately adsorbed on the template by electrostatic adsorption. This method for polyelectrolyte multilayers formation is called electrostatic self-assembly technique. In this paper, self-assembly multilayers of layer-by-layer polyelectrolyte on ZnCO₃ microparticles and mica were studied, and its' application, and some basal results were obtained.1. Size-controlled monodispersed ZnCO₃ microparticles were prepared by a novel nanoseed method. Nanoseed was prepared before the reaction of NaHCO₃ and ZnSO₄. Different volume of nanoseed added into the solution before the reaction can obtain different size of ZnCO₃ microparticles from 320nm to 1.4 μm. Polyelectrolyte PSS and PAH were adsorbed onto ZnCO₃ microparticles by layer-by-layer technique. Hollow microcapsules can be obtained when ZnCO₃ microparticles were dissolved. When polyelectrolyte multilayers were assembled on different size of ZnCO₃ microparticles, different size hollow microcapsules can be obtained after ZnCO₃ microparticles were dissolved by HC1. The size of hollow microcapsules were determined by the size of the ZnCO₃ microparticles, so the hollow microcapsules obtained were also size-controlled.2. Biomimetic laminated composite was fabricated by mimicking the cyclical matrix control process to form the highly structured Mollusca nacre, the structure and growth period of the biomimetic laminated obtained was similar to Mollusca nacre, it can be considered as a model for the research of the formation of Mollusca nacre. The PSS/PAH self-assembled multilayers were built-up through alternative adsorption of polycation and polyanion to mica, And then the deposition of CaCO₃ took place on the multilayers by dipping them into a supersaturated CaCO₃ solution to regulate CaCO₃ crystal. The crystals regulated were different by different charge and group on PSS/PAH self-assembled multilayers surface. The crystals regulated by (PSS/PAH)₁₀PSS is very similar to the crystals existing in natural nacre, but their crystal lattice were different, indicated that electrostatic effect was one of the key factors in crystals morphology control.3. Colloid absorbed to some substance has great signification for base colloid chemistry. We studied the assembly of TiO₂ colloid with positive charges on the polyelectrolyte self-assembly multilayers with negative charges. The TiO₂ colloid adsorbed on the multilayers can be controlled by the change of the property of the multilayers...