Formation and structure of polyacrylamide–silica nanocomposites by sol–gel process

The formation of nanocomposites by the sol–gel reaction of tetraethoxysilane (TEOS) in polyacrylamide (PAAm) is studied. The nanocomposites are prepared in aqueous solution. Fourier transform IR spectroscopy shows that substantial hydrogen bonding occurs in the nanocomposites. The fracture surfaces of the nanocomposites are observed by atomic force microscopy (AFM) as a function of the TEOS content. The AFM images reveal that the PAAm–silica nanocomposite exhibits particle–matrix morphology. It is also found that aggregate formation is more dominant than the particle growth with the TEOS contents. The solution of composite precursor is also applied to spin coating. Furthermore, during the calcination there is an observable change in the silica networks, and then a microinterconnected structure is generated.