Synthesis, characterization, and application of thin films and mesostructured materials using self-assembled surfactant templates.

摘要

The formation of Langmuir monolayers and Langmuir-Blodgett (LB) films with insoluble surfactants (DPPC), reactive surfactants (OTS), and biomolecules (collagen) was studied. The monolayer and LB film characteristics were investigated for combinations of the above materials. The DPPC and OTS monolayers and films created were similar to those from previous work in the area. The inclusion of collagen in the products was investigated to explore the effects of a biomolecule with a hierarchical structure on the self-assembly properties of the other surfactants. Monolayers of collagen alone were not produced because of the molecule's tendency to dissolve into the aqueous subphase. The DPPC LB film showed some defects on a scale of 5 mum. The addition of collagen to the DPPC monolayer did not alter the pi-A isotherm, but the resulting film was more complete than the film with DPPC alone. Collagen molecules networked on the film, but they were mostly segregated from the DPPC molecules in the areas investigated with AFM. The OTS monolayers and films formed more completely than those obtained with DPPC. The reactive nature of the OTS molecules provided a very strong film, which could viably function in many applications. With collagen incorporated into the monolayers, there is little difference on the resulting LB films. The collagen is fairly isolated on the films. The monolayers and films of OTS and DPPC are also similar to those obtained from OTS alone. The AFM analysis shows that there are regions of isolated DPPC molecules incorporated along the surface of the OTS film. Films with all three components (OTS, DPPC, and collagen) are also very similar. There is a lack of homogeneity in the deposited films; the components are isolated in separate domains.; The precursor "sol" presented in this research is an advance in long-term stability for this type of material. Unlike several other attempts at precursor sols, this sol is chemically stable on a time scale of years. The condensation polymerization proceeded to form silicate oligomers of a certain chain length, but the reaction was drastically slowed or stopped because of the conditions within the sol itself. The silicate polymerization proceeded spontaneously with the introduction of water to complete the mesoporous silica films studied. (Abstract shortened by UMI.)