MODIFICATION OF AN INORGANIC-ORGANIC HYBRID COMPOSITE - EFFECT OF ETHYLAMINE

Changes in the physical properties of a sol-gel-derived, poly(tetramethylene oxide)/silica hybrid composite as a function of aging in a strongly basic solution of 70 % ethylamine in water were monitored. Characterization of the in situ modified inorganic phase was carried out using mechanical tensile testing, dynamic mechanical spectrometry, thermogravimetric analysis, swelling studies, and small-angle X-ray scattering experiments. It appears that syneresis, followed by ripening of the original polysilicate phase produces a more sharply phase-separated composite. There are significant and systematic changes in the mechanical and damping characteristics associated with the change in morphology. Additionally, the fractal nature of the system is transformed from a mass fractal to a surface fractal as a result of this solution-induced inorganic modification.