N,N-diethyl-2-methoxybenzamide, an insect repellent compound, was incorporated into cotton textile using the sol-gel method. Evaluation of the results of four different sol-gel formulations showed that a lower condensation rate resulted in significantly better encapsulation. Also investigated was the encapsulation in the presence of other polymers like polymethylmethacrylate (PMMA), polystyrene (PS) and polyvinyl alcohol (PVA) that prolong the release of the repellent. The sol-gel formulation, SiO2 : polymethylmethacrylate (PMMA) (1:0.8), gave smooth fabric and good encapsulation of the insect repellent compound. PS and PVA resulted in cloths which are aesthetically undesirable. Cloths coated with sol-gel PVA gave the best repellent release profile.
Chan, A., del Valle, J., Lao, K., Malapit, C., Chua, M., & So, R. (2009). Evaluation of Silica Sol-Gel Microcapsule for the Controlled Release of Insect Repellent, N,N-Diethyl-2-methoxybenzamide, on Cotton. Philippine Journal of Science, 138 (1), 13-21.