Artificial Nacre by Alternating Preparation of Layer-by-Layer Polymer Films and CaCO₃Strata

In this paper, we described the fabrication of hybrid nanocomposite by bottom-up alternating preparation of organic and inorganic layers, toward the mimicking biomineralization process of natural nacre. The organic layers are layer-by-layer (LBL) polymer thin films of diazo-resins (DAR) and poly(acrylic acid) (PAA), with reactive DAR for cross-linking the thin films and PAA for providing a surface for facilitating the biomineralization. The inorganic layers are CaCO 3 strata, which were prepared via the CO 2 diffusion method. Scanning electron microscopy observations show that the nanocomposite fabricated in this way has the alternate organic−inorganic multilayered structure, similar to the natural nacre's brick-and-mortar structure. The thicknesses of CaCO 3 strata can be controlled by selecting the diffusion time of CO 2 . Moreover, the thickness and content of organic matrixes may be adjusted by controlling the layer number of LBL polymer thin films. TGA analysis reveals that the content of organic composite is about 6.9%, which is close to the content of organic matrix in the natural nacre. This study represents an efficient and controllable way for fabrication of artificial nacre.