AASERT-92 Fabrication of Biomimetic Molecular-Level Composites

摘要

Biological composite materials such as bones, teeth, and shells, consist of apolymeric matrix reinforced by an inorganic phase which forms within the matrix. These materials are distinguished from synthetic composites by the high degree of organization and regularity displayed by the inorganic phase. Inorganic minerals of uniform size, morphology, and crystallographic orientation can be formed in ordered arrays within living cells. Such a process has not been realized in synthetic systems, although recent strong interest in nanoscience has stimulated much research in the area. We have reported an example of a synthetic process which produces composite materials analoguous to those produced by natural biomineralization. The inorganic/organic in-situ synthesized composites display controlled inorganic crystal size, morphology, and orientation, which characteristics are determining features of Type II, or matrix-mediated, biocomposites. The synthetic factors which we attempted to optimize in order to give biominetic properties to synthetic composites were (1) strong binding by the organic matrix of the inorganic reagents (molecular complementarity) (2) good solvation of the inorganic reagents by the polymer, and (3) an ordered, regular polymer environment in which to induce nucleation (matrix preorganization).