Degradable Silyl Ether-Containing Networks From Trifunctional Thiols And Acrylates

The purpose of this study was the synthesis of novel degradable polymer-based devices capable of releasing an encapsulated agent in a controlled manner with specific interest for use as drug delivery materials. Base-catalyzed thiol Michael additions between trithiols and triacrylates containing silyl ether groups were exploited to prepare a series of degradable cross-linked networks. Disodium fluorescein was loaded as a hydrophilic drug surrogate inside the networks, and the degradation of the networks and the release of dye were monitored. The networks were characterized by Fourier transform infrared spectroscopy, and their thermal and mechanical properties were investigated through thermogravimetric analysis and dynamic mechanical analysis. The effects of the monomer structure on degradation, release behavior, and thermal properties were investigated. The networks prepared from more sterically hindered silyl ether monomers exhibited decreased rates of degradation and correspondingly slower release of encapsulated disodium fluorescein dye. The results suggest that the characteristics of the networks can be fine-tuned by manipulation of the group attached to the Si atom in the silyl ether monomers.