AGFD 75 |
| Several studies have reported that the hydrophilic environment provided by the silica matrices synthesized by the sol-gel process using simple alkoxysilanes has been inhospitable for the encapsulation of hydrophobic molecules resulting in their leaching. To address this question, we introduced hydrophobicity into the silica microcapsule in the form of long chain alkyl groups. This was accomplished by the combined hydrolysis and polymerization of an alkyl-alkoxysilane and a simple alkoxysilane. The microcapsules so generated have been used to study the encapsulation of limonene. The objective of this work was to formulate a protocol to synthesize hydrophobic silica microcapsules and determine the parameters of the reaction which exert an influence on the microcapsule size as well as the release of limonene. Our results revealed that increasing the concentration and hydrolysis time of simple alkoxysilanes increased the particle size of the microcapsules; on the other hand, increasing the concentration of alkylalkoxysilane decreased the instant release of limonene providing significant retention of limonene. |
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General Papers
8:00 AM-1:00 PM, Tuesday, August 21, 2007 BCEC -- 255, Oral
Division of Agricultural & Food Chemistry |