Date of Award
Master of Science (MS)
The sol-gel method is employed in developing micro and nanoscale porous materials. This method produces highly customizable chemical structures, using a simple synthesis process. The potential of using such technology in synthesizing drug delivery mechanisms, bioceramics, and biocompatible polymers has resulted in the widespread use of the sol-gel process in biomedical applications. A sol-gel with a highly controlled pore structure can be loaded with a wide range of active ingredients for use as a controlled drug delivery mechanism. As such applications require high accuracy and precision, there is a need for quality control measures in large batch monolith synthesis to ensure adequate ingraining and active ingredient retention within the pore structure. This thesis characterized the mechanical properties of silica sols during an early development phase, called aging, to determine the conditions suitable for efficient active ingredient retention. The mechanical properties of an acid catalyzed silica sol-gel were studied at various aging times to determine whether retention of active ingredient within the pore structure changes as a result of changes in aging time and gel stiffness. There was a significant positive relationship between aging time up to 270 minutes after gelation and gel stiffness. However, the efficiency of active ingredient retention within the pore structure of a model compound, an organic pesticide, was not significantly correlated to stiffness in the aging time frame measured in this study. The change in stiffness over an aging time of 0 to 270 minutes after the gelation phase did not have a significant impact on the performance of this gel for retention of the representative model active ingredient application. Thus, the efficiency of active ingredient loading within the sol-gel pore structure is not altered by aging times within 4.5 hours after gelation and changes in the mechanical properties of increasing stiffness and decreasing hysteresis in that same timeframe.
Kalidindi, Satya, "Effect of Aging Time on Stiffness in Acid Catalyzed Silica Sol-Gels" (2020). All Theses. 3470.